Human evolution

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Human evolution
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{{short description|Evolutionary process leading to anatomically modern humans}}File:Akha cropped.png|thumb|upright|Homo sapiensHomo sapiensHuman evolution is the evolutionary process that led to the emergence of anatomically modern humans, beginning with the evolutionary history of primates—in particular genus Homo—and leading to the emergence of Homo sapiens as a distinct species of the hominid family, the great apes. This process involved the gradual development of traits such as human bipedalism and language,BOOK, Brian K. Hall, Brian K. Hall, Benedikt Hallgrímsson, Strickberger's Evolution,weblink 2011, Jones & Bartlett Publishers, 978-1-4496-6390-2, 488, as well as interbreeding with other hominins, which indicate that human evolution was not linear but a web.WEB,weblink Denisovans and Neandertals: Rethinking Species Boundaries, Living Anthropologically, Antrosio, Jason, 23 August 2018, Human Hybrids. (PDF). Michael F. Hammer. Scientific American, May 2013.JOURNAL, Yong, Ed, Mosaic humans, the hybrid species, New Scientist, July 2011, 211, 2823, 34–38, 10.1016/S0262-4079(11)61839-3, The study of human evolution involves several scientific disciplines, including physical anthropology, primatology, archaeology, paleontology, neurobiology, ethology, linguistics, evolutionary psychology, embryology and genetics.JOURNAL, Heng, Henry H.Q., May 2009, The genome-centric concept: resynthesis of evolutionary theory, BioEssays, 31, 5, 512–525, 10.1002/bies.200800182, 0265-9247, 19334004, Genetic studies show that primates diverged from other mammals about {{Mya|85}}, in the Late Cretaceous period, and the earliest fossils appear in the Paleocene, around {{Mya|55}}.WEB,weblink Meet Your Ancestors, Tyson, Peter, July 1, 2008, Nova ScienceNow, NOVA scienceNOW, PBS; WGBH Educational Foundation, 2015-04-18, Within the Hominoidea (apes) superfamily, the Hominidae family diverged from the Hylobatidae (gibbon) family some 15–20 million years ago; African great apes (subfamily Homininae) diverged from orangutans (Ponginae) about {{Mya|14}}; the Hominini tribe (humans, Australopithecines and other extinct biped genera, and chimpanzee) parted from the Gorillini tribe (gorillas) between 8–9 million years ago; and, in turn, the subtribes Hominina (humans and biped ancestors) and Panina (Chimpanzees) separated 4–7 million years ago.{{harvnb|Planck|2012}}
  • WEB,weblink Bonobos Join Chimps as Closest Human Relatives, TimeTree, 2018-05-19, 2012-06-13, Gibbons, Ann,

Anatomical changes

File:Ape skeletons.png|thumb|upright=1.6|The hominoids are descendants of a common ancestor ]]Human evolution from its first separation from the last common ancestor of humans and chimpanzees is characterized by a number of morphological, developmental, physiological, and behavioral changes. The most significant of these adaptations are bipedalism, increased brain size, lengthened ontogeny (gestation and infancy), and decreased sexual dimorphism. The relationship between these changes is the subject of ongoing debate.{{harvnb|Boyd|Silk|2003}}{{Page needed|date=February 2015}} Other significant morphological changes included the evolution of a power and precision grip, a change first occurring in H. erectus.{{harvnb|Brues|Snow|1965|pp=1–39}}


Bipedalism is the basic adaptation of the hominid and is considered the main cause behind a suite of skeletal changes shared by all bipedal hominids. The earliest hominin, of presumably primitive bipedalism, is considered to be either SahelanthropusJOURNAL, Brunet, Michel, Michel Brunet (paleontologist), Guy, Franck, Pilbeam, David, David Pilbeam, Mackaye, H., Likius, A., Ahounta, D., Beauvilain, A., Blondel, C., Bocherens, H., Boisserie, J., De Bonis, L., Coppens, Y., Dejax, J., Denys, C., Duringer, P., Eisenmann, V., Fanone, G., Fronty, P., Geraads, D., Lehmann, T., Lihoreau, F., Louchart, A., Mahamat, A., Merceron, G., Mouchelin, G., Otero, O., Pelaez Campomanes, P., Ponce De Leon, M., Rage, J., Sapanet, M., Schuster, M., Sudre, J., Tassy, P., Valentin, X., Vignaud, P., Viriot, L., Zazzo, A., Zollikofer, C., 3, July 11, 2002, A new hominid from the Upper Miocene of Chad, Central Africa, Nature, 418, 6894, 145–151, 10.1038/nature00879, 0028-0836, 12110880, or Orrorin, both of which arose some 6 to 7 million years ago. The non-bipedal knuckle-walkers, the gorilla and chimpanzee, diverged from the hominin line over a period covering the same time, so either of Sahelanthropus or Orrorin may be our last shared ancestor. Ardipithecus, a full biped, arose approximately 5.6 million years ago.JOURNAL, 10.1126/science.1175802, 19810190, Ardipithecus ramidus and the Paleobiology of Early Hominids, Science, 326, 5949, 75–86, 2009, White, T. D., Asfaw, B., Beyene, Y., Haile-Selassie, Y., Lovejoy, C. O., Suwa, G., Woldegabriel, G., 2009Sci...326...75W, The early bipeds eventually evolved into the australopithecines and still later into the genus Homo. There are several theories of the adaptation value of bipedalism. It is possible that bipedalism was favored because it freed the hands for reaching and carrying food, saved energy during locomotion,JOURNAL, Kwang Hyun, Ko, 2015, Origins of Bipedalism, Brazilian Archives of Biology and Technology, 10.1590/S1516-89132015060399, 58, 6, 929–934, 1508.02739, enabled long distance running and hunting, provided an enhanced field of vision, and helped avoid hyperthermia by reducing the surface area exposed to direct sun; features all advantageous for thriving in the new savanna and woodland environment created as a result of the East African Rift Valley uplift versus the previous closed forest habitat. A 2007 study provides support for the hypothesis that walking on two legs, or bipedalism, evolved because it used less energy than quadrupedal knuckle-walking.NEWS, July 17, 2007, Study Identifies Energy Efficiency As Reason For Evolution Of Upright Walking,weblink Science Daily, ScienceDaily, Rockville, MD, ScienceDaily, LLC, 2015-04-09,
  • WEB,weblink Study identifies energy efficiency as reason for evolution of upright walking, July 16, 2007, UANews, The University of Arizona Office of University Communications, Tucson, AZ, 2015-04-23, JOURNAL, Sockol, Michael D., Raichlen, David A., Pontzer, Herman, July 24, 2007, Chimpanzee locomotor energetics and the origin of human bipedalism, Proc. Natl. Acad. Sci. U.S.A., 104, 30, 12265–12269, 10.1073/pnas.0703267104, 0027-8424, 1941460, 17636134, 2007PNAS..10412265S, However, recent studies suggest that bipedality without the ability to use fire would not have allowed global dispersal.JOURNAL, David-Barrett, T., Dunbar, R.I.M., 2016, Bipedality and Hair-loss Revisited: The Impact of Altitude and Activity Scheduling, 10.1016/j.jhevol.2016.02.006, Journal of Human Evolution, 94, 72–82, 27178459, 4874949, This change in gait saw a lengthening of the legs proportionately when compared to the length of the arms, which were shortened through the removal of the need for brachiation. Another change is the shape of the big toe. Recent studies suggest that Australopithecines still lived part of the time in trees as a result of maintaining a grasping big toe. This was progressively lost in Habilines.
Anatomically, the evolution of bipedalism has been accompanied by a large number of skeletal changes, not just to the legs and pelvis, but also to the vertebral column, feet and ankles, and skull.{{harvnb|Aiello|Dean|1990}} The femur evolved into a slightly more angular position to move the center of gravity toward the geometric center of the body. The knee and ankle joints became increasingly robust to better support increased weight. To support the increased weight on each vertebra in the upright position, the human vertebral column became S-shaped and the lumbar vertebrae became shorter and wider. In the feet the big toe moved into alignment with the other toes to help in forward locomotion. The arms and forearms shortened relative to the legs making it easier to run. The foramen magnum migrated under the skull and more anterior.{{harvnb|Kondo|1985}}The most significant changes occurred in the pelvic region, where the long downward facing iliac blade was shortened and widened as a requirement for keeping the center of gravity stable while walking; bipedal hominids have a shorter but broader, bowl-like pelvis due to this. A drawback is that the birth canal of bipedal apes is smaller than in knuckle-walking apes, though there has been a widening of it in comparison to that of australopithecine and modern humans, permitting the passage of newborns due to the increase in cranial size but this is limited to the upper portion, since further increase can hinder normal bipedal movement.{{harvnb|Strickberger|2000|pp=475–476}}The shortening of the pelvis and smaller birth canal evolved as a requirement for bipedalism and had significant effects on the process of human birth which is much more difficult in modern humans than in other primates. During human birth, because of the variation in size of the pelvic region, the fetal head must be in a transverse position (compared to the mother) during entry into the birth canal and rotate about 90 degrees upon exit.{{harvnb|Trevathan|2011|p=20}} The smaller birth canal became a limiting factor to brain size increases in early humans and prompted a shorter gestation period leading to the relative immaturity of human offspring, who are unable to walk much before 12 months and have greater neoteny, compared to other primates, who are mobile at a much earlier age.{{harvnb|Curry|2008|pp=106–109}} The increased brain growth after birth and the increased dependency of children on mothers had a major effect upon the female reproductive cycle,Zuk, Marlene (2014), "Paleofantasy: What Evolution Really Tells Us About Sex, Diet, and How We Live" (W.W. Norton & Company) and the more frequent appearance of alloparenting in humans when compared with other hominids.Hrdy, Sarah Blaffer (2011), "Mothers and Others: The Evolutionary Origins of Mutual Understanding" (Harvard Uni Press) Delayed human sexual maturity also led to the evolution of menopause with one explanation providing that elderly women could better pass on their genes by taking care of their daughter's offspring, as compared to having more children of their own.JOURNAL, Wayman, Erin, August 19, 2013, Killer whales, grandmas and what men want: Evolutionary biologists consider menopause,weblink Science News, 0036-8423, 2015-04-24,


(File:Brain size and tooth size in hominins.jpg|thumb|upright=1.7|Brain size and tooth size in hominins)The human species eventually developed a much larger brain than that of other primates—typically {{convert|1,330|cm3|abbr=on}} in modern humans, nearly three times the size of a chimpanzee or gorilla brain.JOURNAL, Schoenemann, P. Thomas, October 2006, Evolution of the Size and Functional Areas of the Human Brain, Annual Review of Anthropology, 35, 379–406, 10.1146/annurev.anthro.35.081705.123210, 0084-6570, After a period of stasis with Australopithecus anamensis and Ardipithecus, species which had smaller brains as a result of their bipedal locomotion,WEB, Brown, Graham, Fairfax, Stephanie, Sarao, Nidhi, Tree of Life Web Project: Human Evolution,weblink, the pattern of encephalization started with Homo habilis, whose {{convert|600|cm3|abbr=on}} brain was slightly larger than that of chimpanzees. This evolution continued in Homo erectus with {{convert|800–1,100|cm3|abbr=on}}, and reached a maximum in Neanderthals with {{convert|1,200–1,900|cm3|abbr=on}}, larger even than modern Homo sapiens. This brain increase manifested during postnatal brain growth, far exceeding that of other apes (heterochrony). It also allowed for extended periods of social learning and language acquisition in juvenile humans, beginning as much as 2 million years ago.Furthermore, the changes in the structure of human brains may be even more significant than the increase in size.JOURNAL, Park, Min S., Nguyen, Andrew D., Aryan, Henry E., U, Hoi Sang, Levy, Michael L., Semendeferi, Katerina, 3, March 2007, Evolution of the human brain: changing brain size and the fossil record, Neurosurgery (journal), Neurosurgery, 60, 3, 555–562, 10.1227/01.NEU.0000249284.54137.32, 0148-396X, 17327801, JOURNAL, Bruner, Emiliano, December 2007, Cranial shape and size variation in human evolution: structural and functional perspectives,, Child's Nervous System, 23, 12, 1357–1365, 10.1007/s00381-007-0434-2, 0256-7040, 17680251, JOURNAL, Potts, Richard, Rick Potts, October 2012, Evolution and Environmental Change in Early Human Prehistory, Annual Review of Anthropology, 41, 151–167, 10.1146/annurev-anthro-092611-145754, 0084-6570, JOURNAL, Leonard, William R., Snodgrass, J. Josh, Robertson, Marcia L., August 2007, Effects of brain evolution on human nutrition and metabolism, Annual Review of Nutrition, 27, 311–327, 10.1146/annurev.nutr.27.061406.093659, 0199-9885, 17439362, (File:Students explore hominid evolution.jpg|alt=Three students hold three different skulls in front of their faces, to show the difference in size and shape compared to the modern head|left|thumb|The size and shape of the skull changed over time. The leftmost, and largest, is a replica of a modern human skull.) The temporal lobes, which contain centers for language processing, have increased disproportionately, as has the prefrontal cortex, which has been related to complex decision-making and moderating social behavior. Encephalization has been tied to increased meat and starches in the diet,PRESS RELEASE, McBroom, Patricia, June 14, 1999, Meat-eating was essential for human evolution, says UC Berkeley anthropologist specializing in diet,weblink Berkeley, University of California Press, 2015-04-25, JOURNAL, Mann, Neil, September 2007, Meat in the human diet: An anthropological perspective,weblink Nutrition & Dietetics, 64, Supplement s4, S102–S107, 10.1111/j.1747-0080.2007.00194.x, 1747-0080, 2012-01-31, NEWS, Zimmer, Carl, Carl Zimmer, For Evolving Brains, a 'Paleo' Diet Full of Carbs,weblink August 13, 2015, The New York Times, August 14, 2015, and the development of cooking,JOURNAL, Organ, Chris, Nunn, Charles L., Machanda, Zarin, Wrangham, Richard W., Richard Wrangham, August 30, 2011, Phylogenetic rate shifts in feeding time during the evolution of Homo, Proc. Natl. Acad. Sci. U.S.A., 108, 35, 14555–14559, 10.1073/pnas.1107806108, 0027-8424, 3167533, 21873223, 2011PNAS..10814555O, and it has been proposed that intelligence increased as a response to an increased necessity for solving social problems as human society became more complex.JOURNAL, David-Barrett, T., Dunbar, R.I.M., 2013, Processing Power Limits Social Group Size: Computational Evidence for the Cognitive Costs of Sociality, Proceedings of the Royal Society B, 280, 1765, 20131151, 10.1098/rspb.2013.1151, 23804623, 3712454, Changes in skull morphology, such as smaller mandibles and mandible muscle attachments, allowed more room for the brain to grow.{{harvnb|Bown|Rose|1987}}The increase in volume of the neocortex also included a rapid increase in size of the cerebellum. Its function has traditionally been associated with balance and fine motor control, but more recently with speech and cognition. The great apes, including hominids, had a more pronounced cerebellum relative to the neocortex than other primates. It has been suggested that because of its function of sensory-motor control and learning complex muscular actions, the cerebellum may have underpinned human technological adaptations, including the preconditions of speech.JOURNAL, Barton, Robert A., Venditti, Chris, October 20, 2014, Rapid Evolution of the Cerebellum in Humans and Other Great Apes, Current Biology, 24, 20, 2440–2444, 10.1016/j.cub.2014.08.056, 25283776, 0960-9822, JOURNAL, Starowicz-Filip, Anna, Milczarek, Olga, Kwiatkowski, Stanisław, Bętkowska-Korpała, Barbara, Prochwicz, Katarzyna, 3, 2013, Cerebellar cognitive affective syndrome CCAS – a case report, Archives of Psychiatry and Psychotherapy, 15, 3, 57–64, 220954272, 10.12740/APP/18666, JOURNAL, Feng Yu, Qing-jun Jiang, Xi-yan Sun, Rong-wei Zhang, 3, August 22, 2014, A new case of complete primary cerebellar agenesis: clinical and imaging findings in a living patient, Brain (journal), Brain, 10.1093/brain/awu239, 1460-2156, 25149410, 138, Pt 6, e353, 4614135, JOURNAL, Weaver, Anne H., March 8, 2005, Reciprocal evolution of the cerebellum and neocortex in fossil humans, Proc. Natl. Acad. Sci. U.S.A., 102, 10, 3576–3580, 10.1073/pnas.0500692102, 0027-8424, 553338, 15731345, 2005PNAS..102.3576W, The immediate survival advantage of encephalization is difficult to discern, as the major brain changes from Homo erectus to Homo heidelbergensis were not accompanied by major changes in technology. It has been suggested that the changes were mainly social and behavioural, including increased empathic abilities,BOOK, Klein, Stefan, 2014, Survival of the Nicest, 978-1615190904, The Experiment, JOURNAL, Social Network Size Affects Neural Circuits in Macaques, Science, 2011-11-04, 0036-8075, 22053054, 697–700, 334, 6056, 10.1126/science.1210027, J., Sallet, R.B., Mars, M.P., Noonan, J.L., Andersson, J.X., O'Reilly, S., Jbabdi, P.L., Croxson, M., Jenkinson, K.L., Miller, 2011Sci...334..697S, increases in size of social groups,JOURNAL, Dunbar, R.I.M., 1992, Neocortex size as a constraint on group size in primates, Journal of Human Evolution, 22, 6, 469–493, 10.1016/0047-2484(92)90081-j, JOURNAL, Processing power limits social group size: computational evidence for the cognitive costs of sociality, Proceedings of the Royal Society of London B: Biological Sciences, 2013-08-22, 0962-8452, 3712454, 23804623, 20131151, 280, 1765, 10.1098/rspb.2013.1151, T., Dávid-Barrett, R.I.M., Dunbar, JOURNAL, Encephalization is not a universal macroevolutionary phenomenon in mammals but is associated with sociality, Proceedings of the National Academy of Sciences, 2010-12-14, 0027-8424, 3003036, 21098277, 21582–21586, 107, 50, 10.1073/pnas.1005246107, Susanne, Shultz, Robin, Dunbar, 2010PNAS..10721582S, and increased behavioural plasticity.JOURNAL, Richard, Potts, 1998, Environmental Hypotheses of Hominin Evolution, American Journal of Physical Anthropology, 107, 93–136, 10.1002/(SICI)1096-8644(1998)107:27, 2019-08-20, Encephalization may be due to a dependency on calorie-dense, difficult-to-acquire food.JOURNAL, Kaplan, Hillard, Hill, Kim, Lancaster, Jane, Hurtado, Magdelena, A Theory of Human Life History Evolution: Diet, Intelligence, and Longevity,weblink Evolutionary Anthropology, 9, 4, 156–185, 10.1002/1520-6505(2000)9:43.0.CO;2-7, 2000-08-16,

Sexual dimorphism

The reduced degree of sexual dimorphism in humans is visible primarily in the reduction of the male canine tooth relative to other ape species (except gibbons) and reduced brow ridges and general robustness of males. Another important physiological change related to sexuality in humans was the evolution of hidden estrus. Humans are the only hominoids in which the female is fertile year round and in which no special signals of fertility are produced by the body (such as genital swelling or overt changes in proceptivity during estrus).BOOK, Tanner, Nancy Makepeace, Tanner, On Becoming Human,weblink 1981, CUP Archive, 978-0-521-28028-0, 202, Nonetheless, humans retain a degree of sexual dimorphism in the distribution of body hair and subcutaneous fat, and in the overall size, males being around 15% larger than females.JOURNAL, Reno, Philip L., Lovejoy, C. Owen, 2015-04-28, From Lucy to Kadanuumuu: balanced analyses ofAustralopithecus afarensisassemblages confirm only moderate skeletal dimorphism, PeerJ, 3, e925, 10.7717/peerj.925, 25945314, 4419524, 2167-8359, These changes taken together have been interpreted as a result of an increased emphasis on pair bonding as a possible solution to the requirement for increased parental investment due to the prolonged infancy of offspring.JOURNAL, Lovejoy, C. Owen, 2009-10-02, Reexamining Human Origins in Light of Ardipithecus ramidus, Science, 326, 5949, 74–74e8, 10.1126/science.1175834, 0036-8075, 2009Sci...326...74L,

Ulnar opposition

The ulnar opposition—the contact between the thumb and the tip of the little finger of the same hand—is unique to the genus Homo,JOURNAL, Young, Richard W, January 2003, Evolution of the human hand: the role of throwing and clubbing, Journal of Anatomy, 202, 1, 165–174, 10.1046/j.1469-7580.2003.00144.x, 0021-8782, 1571064, 12587931, including Neanderthals, the Sima de los Huesos hominins and anatomically modern humans.BOOK, Miriam Ittyerah, Hand Preference and Hand Ability: Evidence from studies in Haptic Cognition, John Benjamins Publishing, 2013, 37–38, 978-9027271648, WEB,weblink The Hand How Its Use Shapes the Brain, Language, and Human Culture, The New York Times, Pantheon Books, Frank R. Wilson, 2 July 2017, In other primates the thumb is short and unable to touch the little finger. The ulnar opposition facilitates the precision grip and power grip of the human hand, underlying all the skilled manipulations.

Other changes

A number of other changes have also characterized the evolution of humans, among them an increased importance on vision rather than smell; a longer juvenile developmental period and higher infant dependency; a smaller gut; faster basal metabolism;JOURNAL, Pontzer, Herman, 2016, Metabolic acceleration and the evolution of human brain size and life history, Nature, 533, 7603, 390–392, 2016Natur.533..390P, 10.1038/nature17654, 27144364, 4942851, loss of body hair; evolution of sweat glands; a change in the shape of the dental arcade from being u-shaped to being parabolic; development of a chin (found in Homo sapiens alone); development of styloid processes; and the development of a descended larynx.

History of study

{{align|right|{{Human timeline}}}}{{align|right|{{Hominins}}}}

Before Darwin

The word homo, the name of the biological genus to which humans belong, is Latin for "human". It was chosen originally by Carl Linnaeus in his classification system.{{efn|See the Binomial nomenclature and Systema Naturae articles.}} The word "human" is from the Latin humanus, the adjectival form of homo. The Latin "homo" derives from the Indo-European root *dhghem, or "earth".{{harvnb|American Heritage Dictionaries (editors)|2006}} Linnaeus and other scientists of his time also considered the great apes to be the closest relatives of humans based on morphological and anatomical similarities.WEB,weblink Nested Hierarchies, the Order of Nature: Carolus Linnaeus, Understanding Evolution: The History of Evolutionary Thought, The University of California at Berkeley, August 2, 2019,


The possibility of linking humans with earlier apes by descent became clear only after 1859 with the publication of Charles Darwin's On the Origin of Species, in which he argued for the idea of the evolution of new species from earlier ones. Darwin's book did not address the question of human evolution, saying only that "Light will be thrown on the origin of man and his history."JOURNAL, Darwin, Charles, 1859, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, Full image view 1st, 488,weblink 1872Natur...5..318B, 5, Nature, 10.1038/005318a0, 121, The first debates about the nature of human evolution arose between Thomas Henry Huxley and Richard Owen. Huxley argued for human evolution from apes by illustrating many of the similarities and differences between humans and apes, and did so particularly in his 1863 book Evidence as to Man's Place in Nature. However, many of Darwin's early supporters (such as Alfred Russel Wallace and Charles Lyell) did not initially agree that the origin of the mental capacities and the moral sensibilities of humans could be explained by natural selection, though this later changed. Darwin applied the theory of evolution and sexual selection to humans when he published The Descent of Man in 1871.{{harvnb|Darwin|1981}}

First fossils

A major problem in the 19th century was the lack of fossil intermediaries. Neanderthal remains were discovered in a limestone quarry in 1856, three years before the publication of On the Origin of Species, and Neanderthal fossils had been discovered in Gibraltar even earlier, but it was originally claimed that these were human remains of a creature suffering some kind of illness.{{harvnb|Montgomery|1988|pp=95–96}} Despite the 1891 discovery by Eugène Dubois of what is now called Homo erectus at Trinil, Java, it was only in the 1920s when such fossils were discovered in Africa, that intermediate species began to accumulate.{{citation needed|date=February 2015}} In 1925, Raymond Dart described Australopithecus africanus.JOURNAL, Dart, Raymond, Raymond Dart, February 7, 1925, Australopithecus africanus: The Man-Ape of South Africa, Nature, 115, 2884, 195–199, 10.1038/115195a0, 0028-0836, 1925Natur.115..195D, The type specimen was the Taung Child, an australopithecine infant which was discovered in a cave. The child's remains were a remarkably well-preserved tiny skull and an endocast of the brain.Although the brain was small (410 cm3), its shape was rounded, unlike that of chimpanzees and gorillas, and more like a modern human brain. Also, the specimen showed short canine teeth, and the position of the foramen magnum (the hole in the skull where the spine enters) was evidence of bipedal locomotion. All of these traits convinced Dart that the Taung Child was a bipedal human ancestor, a transitional form between apes and humans.

The East African fossils

File:Fossil hominids.jpg|thumb|150px|left|Fossil hominid evolution display at The Museum of Osteology, Oklahoma City, Oklahoma, U.S..]]During the 1960s and 1970s, hundreds of fossils were found in East Africa in the regions of the Olduvai Gorge and Lake Turkana. These searches were carried out by the Leakey family, with Louis Leakey and his wife Mary Leakey, and later their son Richard and daughter-in-law Meave, fossil hunters and paleoanthropologists. From the fossil beds of Olduvai and Lake Turkana they amassed specimens of the early hominins: the australopithecines and Homo species, and even Homo erectus.These finds cemented Africa as the cradle of humankind. In the late 1970s and the 1980s, Ethiopia emerged as the new hot spot of paleoanthropology after "Lucy", the most complete fossil member of the species Australopithecus afarensis, was found in 1974 by Donald Johanson near Hadar in the desertic Afar Triangle region of northern Ethiopia. Although the specimen had a small brain, the pelvis and leg bones were almost identical in function to those of modern humans, showing with certainty that these hominins had walked erect.{{harvnb|Johanson|Edey|1981|pp=20–22, 184–185}} Lucy was classified as a new species, Australopithecus afarensis, which is thought to be more closely related to the genus Homo as a direct ancestor, or as a close relative of an unknown ancestor, than any other known hominid or hominin from this early time range; see terms "hominid" and "hominin".BOOK, The Human Lineage, Cartmill, Matt, Fred H. Smith, Kaye B. Brown, 151, 2009, Wiley-Blackwell, 978-0-471-21491-5, (The specimen was nicknamed "Lucy" after the Beatles' song "Lucy in the Sky with Diamonds", which was played loudly and repeatedly in the camp during the excavations.){{harvnb|Johanson|Edey|1981|p=22}} The Afar Triangle area would later yield discovery of many more hominin fossils, particularly those uncovered or described by teams headed by Tim D. White in the 1990s, including Ardipithecus ramidus and Ardipithecus kadabba.JOURNAL, Shreeve, Jamie, July 2010, The Evolutionary Road,weblink National Geographic, 0027-9358, 2015-05-28, In 2013, fossil skeletons of Homo naledi, an extinct species of hominin assigned (provisionally) to the genus Homo, were found in the Rising Star Cave system, a site in South Africa's Cradle of Humankind region in Gauteng province near Johannesburg.JOURNAL, 10.7554/eLife.09560, 4, Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa, eLife, 26354291, 4559886, 2015, Berger, LR, etal, {{As of|2015|9}}, fossils of at least fifteen individuals, amounting to 1,550 specimens, have been excavated from the cave.WEB, Shreeve, Jamie, This Face Changes the Human Story. But How?,weblink 10 September 2015, National Geographic News, 10 September 2015, The species is characterized by a body mass and stature similar to small-bodied human populations, a smaller endocranial volume similar to Australopithecus, and a cranial morphology (skull shape) similar to early Homo species. The skeletal anatomy combines primitive features known from australopithecines with features known from early hominins. The individuals show signs of having been deliberately disposed of within the cave near the time of death. The fossils were dated close to 250,000 years ago,Dirks et al. (2017): between 335 and 236 ka. The lower limit of 236 ka is due to optically stimulated luminescence dating of sediments with U-Th and palaeomagnetic analyses of flowstones; the upper limit of 335 ka is due to U-series and electron spin resonance (US-ESR) dating of two H. naledi teeth, to {{val|253|82|70|u=ka}}, for an estimated age of the fossils of {{val|253|82|17|u=ka}}. and thus are not a direct ancestor but a contemporary with the first appearance of larger-brained anatomically modern humans.JOURNAL, Dirks, Paul H.G.M., Eric M., Roberts, Hannah, Hilbert-Wolf, Jan D., Kramers, John, Hawks, Anthony, Dosseto, Mathieu, Duval, Marina, Elliott, Mary, Evans, Rainer, Grün, John, Hellstrom, Andy I.R., Herries, Renaud, Joannes-Boyau, Tebogo V., Makhubela, Christa J., Placzek, Jessie, Robbins, Carl, Spandler, Jelle, Wiersma, Jon, Woodhead, Lee R., Berger, 2, 9 May 2017, The age of Homo naledi and associated sediments in the Rising Star Cave, South Africa, eLife, 6, e24231, 10.7554/eLife.24231, 28483040, 5423772, free, {{collapsible list| title= Full list of authors| bullets= true| Paul H.G.M. Dirks| Eric M. Roberts| Hannah Hilbert-Wolf| Jan D. Kramers| John Hawks| Anthony Dosseto| Mathieu Duval| Marina Elliott| Mary Evans| Rainer Grün| John Hellstrom| Andy I.R. Herries| Renaud Joannes-Boyau| Tebogo V. Makhubela| Christa J. Placzek| Jessie Robbins| Carl Spandler| Jelle Wiersma| Jon Woodhead| Lee R. Berger}}

The genetic revolution

File:Louis Leakey.jpg|thumb|150px|left|Louis Leakey examining skulls from Olduvai Gorge, TanzaniaTanzaniaThe genetic revolution in studies of human evolution started when Vincent Sarich and Allan Wilson measured the strength of immunological cross-reactions of blood serum albumin between pairs of creatures, including humans and African apes (chimpanzees and gorillas).JOURNAL, Sarich, V.M., Wilson, A.C., Immunological time scale for hominid evolution, Science, 158, 3805, 1200–1204, 1967, 4964406, 10.1126/science.158.3805.1200, 1967Sci...158.1200S, The strength of the reaction could be expressed numerically as an immunological distance, which was in turn proportional to the number of amino acid differences between homologous proteins in different species. By constructing a calibration curve of the ID of species' pairs with known divergence times in the fossil record, the data could be used as a molecular clock to estimate the times of divergence of pairs with poorer or unknown fossil records.In their seminal 1967 paper in Science, Sarich and Wilson estimated the divergence time of humans and apes as four to five million years ago, at a time when standard interpretations of the fossil record gave this divergence as at least 10 to as much as 30 million years. Subsequent fossil discoveries, notably "Lucy", and reinterpretation of older fossil materials, notably Ramapithecus, showed the younger estimates to be correct and validated the albumin method.Progress in DNA sequencing, specifically mitochondrial DNA (mtDNA) and then Y-chromosome DNA (Y-DNA) advanced the understanding of human origins.{{harvnb|M'charek|2005|p=96}}{{harvnb|DeSalle|Tattersall|2008|p=146}}{{harvnb|Trent|2005|p=6}} Application of the molecular clock principle revolutionized the study of molecular evolution.On the basis of a separation from the orangutan between 10 and 20 million years ago, earlier studies of the molecular clock suggested that there were about 76 mutations per generation that were not inherited by human children from their parents; this evidence supported the divergence time between hominins and chimps noted above. However, a 2012 study in Iceland of 78 children and their parents suggests a mutation rate of only 36 mutations per generation; this datum extends the separation between humans and chimps to an earlier period greater than 7 million years ago (Ma). Additional research with 226 offspring of wild chimp populations in 8 locations suggests that chimps reproduce at age 26.5 years, on average; which suggests the human divergence from chimps occurred between 7 and 13 million years ago. And these data suggest that Ardipithecus (4.5 Ma), Orrorin (6 Ma) and Sahelanthropus (7 Ma) all may be on the hominid lineage, and even that the separation may have occurred outside the East African Rift region.Furthermore, analysis of the two species' genes in 2006 provides evidence that after human ancestors had started to diverge from chimpanzees, interspecies mating between "proto-human" and "proto-chimps" nonetheless occurred regularly enough to change certain genes in the new gene pool:
A new comparison of the human and chimp genomes suggests that after the two lineages separated, they may have begun interbreeding... A principal finding is that the X chromosomes of humans and chimps appear to have diverged about 1.2 million years more recently than the other chromosomes.
The research suggests:
There were in fact two splits between the human and chimp lineages, with the first being followed by interbreeding between the two populations and then a second split. The suggestion of a hybridization has startled paleoanthropologists, who nonetheless are treating the new genetic data seriously.NEWS, Wade, Nicholas, Nicholas Wade, May 18, 2006, Two Splits Between Human and Chimp Lines Suggested,weblink The New York Times, 2015-04-20,

The quest for the earliest hominin

In the 1990s, several teams of paleoanthropologists were working throughout Africa looking for evidence of the earliest divergence of the hominin lineage from the great apes. In 1994, Meave Leakey discovered Australopithecus anamensis. The find was overshadowed by Tim D. White's 1995 discovery of Ardipithecus ramidus, which pushed back the fossil record to {{ma|4.2}}.In 2000, Martin Pickford and Brigitte Senut discovered, in the Tugen Hills of Kenya, a 6-million-year-old bipedal hominin which they named Orrorin tugenensis. And in 2001, a team led by Michel Brunet discovered the skull of Sahelanthropus tchadensis which was dated as {{ma|7.2|million years ago}}, and which Brunet argued was a bipedal, and therefore a hominid—that is, a hominin (}} Hominidae; terms "hominids" and hominins).

Human dispersal

{{multiple image
| width1 = 360
| width2 = 260
| footer = Different models for the beginning of the present human species.
| image1 = World map of prehistoric human migrations.jpg
| alt1 = Map with arrows emanating from Africa, across Eurasia, to Australia and the Americas.
| caption1 = A global mapping model of human migration, based from divergence of the mitochondrial DNA (which indicates the matrilineage).JOURNAL, Behar, Doron M., Villems, Richard, Soodyall, Himla, Himla Soodyall, Blue-Smith, Jason, Pereira, Luisa, Metspalu, Ene, Scozzari, Rosaria, Makkan, Heeran, Tzur, Shay, Comas, David, Bertranpetit, Jaume, Quintana-Murci, Lluis, Tyler-Smith, Chris, Wells, R. Spencer, Rosset, Saharon, The Genographic Consortium, 3, May 9, 2008, The Dawn of Human Matrilineal Diversity,weblink American Journal of Human Genetics, 82, 5, 1130–1140, 10.1016/j.ajhg.2008.04.002, 0002-9297, 2427203, 18439549, 2015-04-20,
  • JOURNAL, Gonder, Mary Katherine, Mortensen, Holly M., Reed, Floyd A., de Sousa, Alexandra, Tishkoff, Sarah A., 3, March 2007, Whole-mtDNA Genome Sequence Analysis of Ancient African Lineages,weblink Molecular Biology and Evolution, 24, 3, 757–768, 10.1093/molbev/msl209, 0737-4038, 17194802, 2015-04-20,
  • Tishkoff and Reed (2009) Timescale (ka) indicated by colours.

| image2 = Homo_trellis.jpg
| alt2 = Trellis of intermingling populations for the last two million years.
| caption2 = A "trellis" (as Milford H. Wolpoff called it) that emphasizes back-and-forth gene flow among geographic regions.JOURNAL, Templeton, Alan R., Alan Templeton, 2005, Haplotype Trees and Modern Human Origins, American Journal of Physical Anthropology, 128, Supplement 41 (Yearbook of Physical Anthropology), 33–59, 10.1002/ajpa.20351, 0002-9483, 16369961, }}
{{See also|Early human migrations|Recent African origin of modern humans|Multiregional origin of modern humans|Early hominids in Southeast Asia}}Anthropologists in the 1980s were divided regarding some details of reproductive barriers and migratory dispersals of the genus Homo. Subsequently, genetics has been used to investigate and resolve these issues. According to the Sahara pump theory evidence suggests that genus Homo have migrated out of Africa at least three and possibly four times (e.g. Homo erectus, Homo heidelbergensis and two or three times for Homo sapiens). Recent evidence suggests these dispersals are closely related to fluctuating periods of climate change.Peter B. deMenocal, (2016) "Climate Shocks" (Scientific American Vol 25, No 4)Recent evidence suggests that humans may have left Africa half a million years earlier than previously thought. A joint Franco-Indian team has found human artifacts in the Siwalk Hills north of New Delhi dating back at least 2.6 million years. This is earlier than the previous earliest finding of genus Homo at Dmanisi, in Georgia, dating to 1.85 million years. Although controversial, tools found at a Chinese cave strengthen the case that humans used tools as far back as 2.48 million years ago.Barras, Colin (2016), "Stone Tools hint humans reached Asia much earlier" (New Scientist 6 February 2016) This suggests that the Asian "Chopper" tool tradition, found in Java and northern China may have left Africa before the appearance of the Acheulian hand axe.

Dispersal of modern Homo sapiens

Up until the genetic evidence became available there were two dominant models for the dispersal of modern humans. The multiregional hypothesis proposed that the genus Homo contained only a single interconnected population as it does today (not separate species), and that its evolution took place worldwide continuously over the last couple of million years. This model was proposed in 1988 by Milford H. Wolpoff.JOURNAL, Wolpoff, Milford H., Milford H. Wolpoff, Hawks, John, John D. Hawks, Caspari, Rachel, May 2000, Multiregional, Not Multiple Origins,weblink American Journal of Physical Anthropology, 112, 1, 129–136, 10.1002/(SICI)1096-8644(200005)112:13.0.CO;2-K, 0002-9483, 10766948, JOURNAL, Wolpoff, Milford H., Spuhler, James N., Smith, Fred H., Radovcic, Jakov, Pope, Geoffrey, Frayer, David W., Eckhardt, Robert, Clark, Geoff, 3, August 12, 1988, Modern Human Origins, Science, 241, 4867, 772–774, 1988Sci...241..772W, 10.1126/science.3136545, 0036-8075, 3136545, In contrast the "out of Africa" model proposed that modern H. sapiens speciated in Africa recently (that is, approximately 200,000 years ago) and the subsequent migration through Eurasia resulted in nearly complete replacement of other Homo species. This model has been developed by Chris B. Stringer and Peter Andrews.NEWS, Owen, James, July 18, 2007,weblink Modern Humans Came Out of Africa, 'Definitive' Study Says, National Geographic News, Washington, DC, National Geographic Society, 2011-05-14, JOURNAL, Stringer, Chris B., Andrews, Peter, March 11, 1988, Genetic and fossil evidence for the origin of modern humans, Science, 239, 4845, 1263–1268, 1988Sci...239.1263S, 10.1126/science.3125610, 0036-8075, 3125610, (File:Homo sapiens dispersal routes.jpg|thumb|300px|Known H. sapiens migration routes in the Pleistocene.)Sequencing mtDNA and Y-DNA sampled from a wide range of indigenous populations revealed ancestral information relating to both male and female genetic heritage, and strengthened the Out of Africa theory and weakened the views of Multiregional Evolutionism.{{harvnb|Webster|2010|p=53}} Aligned in genetic tree differences were interpreted as supportive of a recent single origin.{{harvnb|Ramachandran|Hua Tang|Gutenkunst|Bustamante|2010|p=606}} Analyses have shown a greater diversity of DNA patterns throughout Africa, consistent with the idea that Africa is the ancestral home of mitochondrial Eve and Y-chromosomal Adam, and that modern human dispersal out of Africa has only occurred over the last 55,000 years.{{harvnb|Kutty|2009|p=40}}"Out of Africa" has thus gained much support from research using female mitochondrial DNA and the male Y chromosome. After analysing genealogy trees constructed using 133 types of mtDNA, researchers concluded that all were descended from a female African progenitor, dubbed Mitochondrial Eve. "Out of Africa" is also supported by the fact that mitochondrial genetic diversity is highest among African populations.JOURNAL, Cann, Rebecca L., Rebecca L. Cann, Stoneking, Mark, Mark Stoneking, Wilson, Allan C., Allan Wilson, January 1, 1987, Mitochondrial DNA and human evolution,weblink Nature, 325, 6099, 31–36, 1987Natur.325...31C, 10.1038/325031a0, 0028-0836, 3025745,weblink" title="">weblink 2010-08-13, 2015-04-21, A broad study of African genetic diversity, headed by Sarah Tishkoff, found the San people had the greatest genetic diversity among the 113 distinct populations sampled, making them one of 14 "ancestral population clusters". The research also located a possible origin of modern human migration in south-western Africa, near the coastal border of Namibia and Angola.NEWS, Gill, Victoria, May 1, 2009, Africa's genetic secrets unlocked,weblink BBC News, London, BBC, 2011-06-08, The results were published in the online edition of the journal Science. The fossil evidence was insufficient for archaeologist Richard Leakey to resolve the debate about exactly where in Africa modern humans first appeared.{{harvnb|Leakey|1994|pp=87–89}} Studies of haplogroups in Y-chromosomal DNA and mitochondrial DNA have largely supported a recent African origin.JOURNAL, Jorde, Lynn B., Bamshad, Michael, Rogers, Alan R., Alan R. Rogers, February 1998, Using mitochondrial and nuclear DNA markers to reconstruct human evolution, BioEssays, 20, 2, 126–136, 10.1002/(SICI)1521-1878(199802)20:23.0.CO;2-R, 0265-9247, 9631658, All the evidence from autosomal DNA also predominantly supports a Recent African origin. However, evidence for archaic admixture in modern humans, both in Africa and later, throughout Eurasia has recently been suggested by a number of studies.JOURNAL, Wall, Jeffrey D., Lohmueller, Kirk E., Plagnol, Vincent, August 2009, Detecting Ancient Admixture and Estimating Demographic Parameters in Multiple Human Populations, 19420049, Molecular Biology and Evolution, 26, 8, 1823–1827, 10.1093/molbev/msp096, 0737-4038, 2734152, Recent sequencing of NeanderthalJOURNAL, Green, Richard E., Krause, Johannes, Johannes Krause, Briggs, Adrian W., Maricic, Stenzel, Kircher, Patterson, Li, Zhai, Fritz, Hansen, Durand, Malaspinas, Jensen, Marques-Bonet, Alkan, Prüfer, Meyer, Burbano, Good, Schultz, Aximu-Petri, Butthof, Höber, Höffner, Siegemund, Weihmann, Nusbaum, Lander, Russ, 3, May 7, 2010, A Draft Sequence of the Neandertal Genome, Science, 328, 5979, 710–722, 2010Sci...328..710G, 10.1126/science.1188021, 0036-8075, 20448178, 5100745, and Denisovan genomes shows that some admixture with these populations has occurred. Modern humans outside Africa have 2–4% Neanderthal alleles in their genome, and some Melanesians have an additional 4–6% of Denisovan alleles. These new results do not contradict the "out of Africa" model, except in its strictest interpretation, although they make the situation more complex. After recovery from a genetic bottleneck that some researchers speculate might be linked to the Toba supervolcano catastrophe, a fairly small group left Africa and interbred with Neanderthals, probably in the Middle East, on the Eurasian steppe or even in North Africa before their departure. Their still predominantly African descendants spread to populate the world. A fraction in turn interbred with Denisovans, probably in south-east Asia, before populating Melanesia.JOURNAL, Reich, David, Patterson, Nick, Kircher, Martin, Delfin, Frederick, Nandineni, Madhusudan R., Pugach, Irina, Ko, Albert Min-Shan, Ko, Ying-Chin, Jinam, Timothy A., Phipps, Maude E., Saitou, Naruya, Wollstein, Andreas, Kayser, Manfred, Pääbo, Svante, Stoneking, Mark, 3, October 7, 2011, Denisova Admixture and the First Modern Human Dispersals into Southeast Asia and Oceania, American Journal of Human Genetics, 89, 4, 516–528, 10.1016/j.ajhg.2011.09.005, 0002-9297, 3188841, 21944045, HLA haplotypes of Neanderthal and Denisova origin have been identified in modern Eurasian and Oceanian populations. The Denisovan EPAS1 gene has also been found in Tibetan populations.Huertha Sanchez, Emilia et al (2014), "Altitude adaptation in Tibetans caused by introgression of Denisovan-like DNA" (Nature Vol 512, 14 August 2014) Studies of the human genome using machine learning have identified additional genetic contributions in Eurasians from an "unknown" ancestral population potentially related to the Neanderthal-Denisovan lineage.WEB,weblink Artificial intelligence applied to the genome identifies an unknown human ancestor, ScienceDaily, en, 2019-01-17, File:Spreading homo sapiens la.svg|thumb|320px| A map of early human migrationsearly human migrationsThere are still differing theories on whether there was a single exodus from Africa or several. A multiple dispersal model involves the Southern Dispersal theory,WEB,weblink Searching for traces of the Southern Dispersal, Lahr, Marta Mirazón, Marta Mirazón Lahr, Petraglia, Mike, Stokes, Stephen, Duller, Geoff, 3, Leverhulme Centre for Human Evolutionary Studies, University of Cambridge, Cambridge,weblink" title="">weblink 2012-05-10, 2015-04-21, which has gained support in recent years from genetic, linguistic and archaeological evidence. In this theory, there was a coastal dispersal of modern humans from the Horn of Africa crossing the Bab el Mandib to Yemen at a lower sea level around 70,000 years ago. This group helped to populate Southeast Asia and Oceania, explaining the discovery of early human sites in these areas much earlier than those in the Levant. This group seems to have been dependent upon marine resources for their survival.Stephen Oppenheimer has proposed a second wave of humans may have later dispersed through the Persian Gulf oases, and the Zagros mountains into the Middle East. Alternatively it may have come across the Sinai Peninsula into Asia, from shortly after 50,000 yrs BP, resulting in the bulk of the human populations of Eurasia. It has been suggested that this second group possibly possessed a more sophisticated "big game hunting" tool technology and was less dependent on coastal food sources than the original group. Much of the evidence for the first group's expansion would have been destroyed by the rising sea levels at the end of each glacial maximum. The multiple dispersal model is contradicted by studies indicating that the populations of Eurasia and the populations of Southeast Asia and Oceania are all descended from the same mitochondrial DNA L3 lineages, which support a single migration out of Africa that gave rise to all non-African populations.JOURNAL, Macaulay, Vincent, Hill, Catherine, Achilli, Alessandro, Rengo, Chiara, Clarke, D, Meehan, W, Blackburn, J, Semino, O, Scozzari, R, Cruciani, F, Taha, A, Shaari, N.K., Raja, J.M., Ismail, P, Zainuddin, Z, Goodwin, W, Bulbeck, D, Bandelt, H.J., Oppenheimer, S, Torroni, A, Richards, M, 3, May 13, 2005, Single, Rapid Coastal Settlement of Asia Revealed by Analysis of Complete Mitochondrial Genomes, Science, 308, 5724, 1034–1036, 2005Sci...308.1034M, 10.1126/science.1109792, 0036-8075, 15890885,weblink Stephen Oppenheimer, on the basis of the early date of Badoshan Iranian Aurignacian, suggests that this second dispersal, may have occurred with a pluvial period about 50,000 years before the present, with modern human big-game hunting cultures spreading up the Zagros Mountains, carrying modern human genomes from Oman, throughout the Persian Gulf, northward into Armenia and Anatolia, with a variant travelling south into Israel and to Cyrenicia.Oppenheimer, Stephen (2012), "Out of Eden: The Peopling of the World" (Robinson; New Ed edition (March 1, 2012))


The evidence on which scientific accounts of human evolution are based comes from many fields of natural science. The main source of knowledge about the evolutionary process has traditionally been the fossil record, but since the development of genetics beginning in the 1970s, DNA analysis has come to occupy a place of comparable importance. The studies of ontogeny, phylogeny and especially evolutionary developmental biology of both vertebrates and invertebrates offer considerable insight into the evolution of all life, including how humans evolved. The specific study of the origin and life of humans is anthropology, particularly paleoanthropology which focuses on the study of human prehistory.{{harvnb|Stanford|Allen|Antón|2009}}

Evidence from molecular biology

File:Hominidae chart.svg|upright=1.5|thumb|Family tree showing the extant hominoids: humans (genus Homo), chimpanzees and bonobos (genus Pan), gorillas (genus Gorilla), orangutans (genus Pongo), and gibbons (four genera of the family Hylobatidae: Hylobates, Hoolock, Nomascus, and SymphalangusSymphalangusThe closest living relatives of humans are bonobos and chimpanzees (both genus Pan) and gorillas (genus Gorilla).JOURNAL, Wood, Bernard A., Richmond, Brian G., July 2000, Human evolution: taxonomy and paleobiology, Journal of Anatomy, 197, 1, 19–60, 10.1046/j.1469-7580.2000.19710019.x, 1469-7580, 10999270, 1468107, With the sequencing of both the human and chimpanzee genome, {{as of|2012|lc=y}} estimates of the similarity between their DNA sequences range between 95% and 99%.JOURNAL, Ajit, Varki, Ajit Varki, Nelson, David L., October 2007, Genomic Comparisons of Humans and Chimpanzees,weblink Annual Review of Anthropology, 36, 191–209, 10.1146/annurev.anthro.36.081406.094339, 0084-6570, 2015-04-26, Sequence differences from the human genome were confirmed to be ∼1% in areas that can be precisely aligned, representing ∼35 million single base-pair differences. Some 45 million nucleotides of insertions and deletions unique to each lineage were also discovered, making the actual difference between the two genomes ∼4%., JOURNAL, Sayers, Ken, Raghanti, Mary Ann, Lovejoy, C. Owen, Owen Lovejoy (anthropologist), October 2012, Human Evolution and the Chimpanzee Referential Doctrine, Annual Review of Anthropology, 41, 119–138, 10.1146/annurev-anthro-092611-145815, 0084-6570, By using the technique called the molecular clock which estimates the time required for the number of divergent mutations to accumulate between two lineages, the approximate date for the split between lineages can be calculated.The gibbons (family Hylobatidae) and then orangutans (genus Pongo) were the first groups to split from the line leading to the hominins, including humans—followed by gorillas, and, ultimately, by the chimpanzees (genus Pan). The splitting date between hominin and chimpanzee lineages is placed by some between {{Mya|4|8}}, that is, during the Late Miocene.{{harvnb|Dawkins|2004}}
  • WEB,weblink Find Time of Divergence: Hominidae versus Hylobatidae, TimeTree, 2015-04-18, JOURNAL, Ruvolo, Maryellen, October 1997, Genetic Diversity in Hominoid Primates, Annual Review of Anthropology, 26, 515–540, 10.1146/annurev.anthro.26.1.515, 0084-6570, JOURNAL, Ruvolo, Maryellen, March 1997, Molecular Phylogeny of the Hominoids: Inferences from Multiple Independent DNA Sequence Data Sets,weblink Molecular Biology and Evolution, 14, 3, 248–265, 10.1093/oxfordjournals.molbev.a025761, 0737-4038, 9066793, Speciation, however, appears to have been unusually drawn-out. Initial divergence occurred sometime between {{Mya|7|13}}, but ongoing hybridization blurred the separation and delayed complete separation during several millions of years. Patterson (2006) dated the final divergence at {{Mya|5|6}}.JOURNAL, Patterson, N, Richter, DJ, Gnerre, S, Lander, ES, Reich, D, 2006, Genetic evidence for complex speciation of humans and chimpanzees, Nature, 441, 7097, 1103–1108, 10.1038/nature04789, 16710306, 2006Natur.441.1103P,
Genetic evidence has also been employed to resolve the question of whether there was any gene flow between early modern humans and Neanderthals, and to enhance our understanding of the early human migration patterns and splitting dates. By comparing the parts of the genome that are not under natural selection and which therefore accumulate mutations at a fairly steady rate, it is possible to reconstruct a genetic tree incorporating the entire human species since the last shared ancestor.Each time a certain mutation (single-nucleotide polymorphism) appears in an individual and is passed on to his or her descendants a haplogroup is formed including all of the descendants of the individual who will also carry that mutation. By comparing mitochondrial DNA which is inherited only from the mother, geneticists have concluded that the last female common ancestor whose genetic marker is found in all modern humans, the so-called mitochondrial Eve, must have lived around 200,000 years ago.


Human evolutionary genetics studies how one human genome differs from the other, the evolutionary past that gave rise to it, and its current effects. Differences between genomes have anthropological, medical and forensic implications and applications. Genetic data can provide important insight into human evolution.

Evidence from the fossil record

File:Homo habilis-KNM ER 1813.jpg|thumb|upright|Replica of fossil skull of Homo habilis. Fossil number KNM ER 1813, found at Koobi Fora, KenyaKenyaFile:Homo ergaster.jpg|thumb|upright|Replica of fossil skull of Homo ergasterHomo ergasterThere is little fossil evidence for the divergence of the gorilla, chimpanzee and hominin lineages.JOURNAL, Begun, David R., October 2010, Miocene Hominids and the Origins of the African Apes and Humans, Annual Review of Anthropology, 39, 67–84, 10.1146/annurev.anthro.012809.105047, 0084-6570, The earliest fossils that have been proposed as members of the hominin lineage are Sahelanthropus tchadensis dating from {{mya|7}}, Orrorin tugenensis dating from {{mya|5.7}}, and Ardipithecus kadabba dating to {{mya|5.6}}. Each of these have been argued to be a bipedal ancestor of later hominins but, in each case, the claims have been contested. It is also possible that one or more of these species are ancestors of another branch of African apes, or that they represent a shared ancestor between hominins and other apes.The question then of the relationship between these early fossil species and the hominin lineage is still to be resolved. From these early species, the australopithecines arose around {{mya|4}} and diverged into robust (also called Paranthropus) and gracile branches, one of which (possibly A. garhi) probably went on to become ancestors of the genus Homo. The australopithecine species that is best represented in the fossil record is Australopithecus afarensis with more than one hundred fossil individuals represented, found from Northern Ethiopia (such as the famous "Lucy"), to Kenya, and South Africa. Fossils of robust australopithecines such as Au. robustus (or alternatively Paranthropus robustus) and Au./P. boisei are particularly abundant in South Africa at sites such as Kromdraai and Swartkrans, and around Lake Turkana in Kenya.The earliest member of the genus Homo is Homo habilis which evolved around {{Mya|2.8}}. Homo habilis is the first species for which we have positive evidence of the use of stone tools. They developed the Oldowan lithic technology, named after the Olduvai Gorge in which the first specimens were found. Some scientists consider Homo rudolfensis, a larger bodied group of fossils with similar morphology to the original H. habilis fossils, to be a separate species while others consider them to be part of H. habilis—simply representing intraspecies variation, or perhaps even sexual dimorphism. The brains of these early hominins were about the same size as that of a chimpanzee, and their main adaptation was bipedalism as an adaptation to terrestrial living.During the next million years, a process of encephalization began and, by the arrival (about {{Mya|1.9}}) of Homo erectus in the fossil record, cranial capacity had doubled. Homo erectus were the first of the hominins to emigrate from Africa, and, from {{Mya|1.8|1.3}}, this species spread through Africa, Asia, and Europe. One population of H. erectus, also sometimes classified as a separate species Homo ergaster, remained in Africa and evolved into Homo sapiens. It is believed that these species, H. erectus and H. ergaster, were the first to use fire and complex tools.The earliest transitional fossils between H. ergaster/erectus and archaic H. sapiens are from Africa, such as Homo rhodesiensis, but seemingly transitional forms were also found at Dmanisi, Georgia. These descendants of African H. erectus spread through Eurasia from ca. 500,000 years ago evolving into H. antecessor, H. heidelbergensis and H. neanderthalensis. The earliest fossils of anatomically modern humans are from the Middle Paleolithic, about 200,000 years ago such as the Omo remains of Ethiopia; later fossils from Es Skhul cave in Israel and Southern Europe begin around 90,000 years ago ({{Mya|0.09}}).As modern humans spread out from Africa, they encountered other hominins such as Homo neanderthalensis and the Denisovans, who may have evolved from populations of Homo erectus that had left Africa around {{mya|2}}. The nature of interaction between early humans and these sister species has been a long-standing source of controversy, the question being whether humans replaced these earlier species or whether they were in fact similar enough to interbreed, in which case these earlier populations may have contributed genetic material to modern humans.{{harvnb|Wood|2009|pp=17–27}}NEWS, Mitchell, Alanna, January 30, 2012, DNA Turning Human Story Into a Tell-All,weblink The New York Times, 2012-02-13, This migration out of Africa is estimated to have begun about 70,000 years BP and modern humans subsequently spread globally, replacing earlier hominins either through competition or hybridization. They inhabited Eurasia and Oceania by 40,000 years BP, and the Americas by at least 14,500 years BP.JOURNAL, Wood, Bernard A., December 1996, Human evolution, BioEssays, 18, 12, 945–954, 10.1002/bies.950181204, 0265-9247, 8976151,

Inter-species breeding

{{further|Interbreeding between archaic and modern humans}}The hypothesis of interbreeding, also known as hybridization, admixture or hybrid-origin theory, has been discussed ever since the discovery of Neanderthal remains in the 19th century.BOOK, Huxley, T., Collected Essays: Volume VII, Man's Place in Nature, 1890, The Aryan Question and Pre-Historic Man,weblink The linear view of human evolution began to be abandoned in the 1970s as different species of humans were discovered that made the linear concept increasingly unlikely. In the 21st century with the advent of molecular biology techniques and computerization, whole-genome sequencing of Neanderthal and human genome were performed, confirming recent admixture between different human species. In 2010, evidence based on molecular biology was published, revealing unambiguous examples of interbreeding between archaic and modern humans during the Middle Paleolithic and early Upper Paleolithic. It has been demonstrated that interbreeding happened in several independent events that included Neanderthals and Denisovans, as well as several unidentified hominins.Our ancestors mated with the mystery ‘Denisovan’ people – twice. Andy Coghlan, New Scientist. 15 March 2018. Today, approximately 2% of DNA from most Europeans and Asians is Neanderthal, with traces of Denisovan heritage.NEWS, Wei-Haas, Maya, Ancient Girl's Parents Were Two Different Human Species – Born 90,000 years ago, the child is the first direct evidence of interbreeding among Neanderthals and their cousins the Denisovans.,weblink 22 August 2018, National Geographic, 22 August 2018, Also, 4–6% of modern Melanesian genetics are Denisovan. Comparisons of the human genome to the genomes of Neandertals, Denisovans and apes can help identify features that set modern humans apart from other hominin species. In a 2016 comparative genomics study, a Harvard Medical School/UCLA research team made a world map on the distribution and made some predictions about where Denisovan and Neanderthal genes may be impacting modern human biology.A world map of Neanderthal and Denisovan ancestry in modern humans. March 28, 2016.Sriram Sankararaman, Swapan Mallick, Nick Patterson, David Reich. "The Combined Landscape of Denisovan and Neanderthal Ancestry in Present-Day Humans". Current Biology, 2016; {{doi|10.1016/j.cub.2016.03.037}}For example, comparative studies in the mid-2010s found several traits related to neurological, immunological,Human-Neandertal Comparisons. Tara Marathe. Science Magazine. 2010. developmental, and metabolic phenotypes, that were developed by archaic humans to European and Asian environments and inherited to modern humans through admixture with local hominins.Introgression of Neandertal- and Denisovan-like Haplotypes Contributes to Adaptive Variation in Human Toll-like Receptors. Michael Dannemann, Aida M. Andrés, Janet Kelso. volume 98, issue 1, pp. 22–33, January 07, 2016. {{doi|10.1016/j.ajhg.2015.11.015}}Archaic Hominin Admixture Facilitated Adaptation to Out-of-Africa Environments. Rachel M. Gittelman, Joshua G. Schraiber, Benjamin Vernot, Carmen Mikacenic, Mark M. Wurfel, Joshua M. Akey. Current Biology. Volume 26, issue: 24, pp. 3375–3382. November 10, 2016. {{doi|10.1016/j.cub.2016.10.041}}Although the narratives of human evolution are often contentious, several discoveries since 2010 show that human evolution should not be seen as a simple linear or branched progression, but a mix of related species. In fact, genomic research has shown that hybridization between substantially diverged lineages is the rule, not the exception, in human evolution.JOURNAL, The Hybrid Origin of "Modern" Humans, Rebecca, Rogers Ackermann, Alex, Mackay, Michael L, Arnold, Evolutionary Biology, October 2015, 10.1007/s11692-015-9348-1, 43, 1, 1–11, Furthermore, it is argued that hybridization was an essential creative force in the emergence of modern humans.

Before Homo

{{For| evolutionary history before primates|Evolution of mammals|Evolutionary history of life|Timeline of human evolution}}

Early evolution of primates

{{see also|Evolution of primates}}The evolutionary history of the primates can be traced back 65 million years.{{harvnb|Maxwell|1984|p=296}}
  • JOURNAL, Rui Zhang, Yin-Qiu Wang, Bing Su, July 2008, Molecular Evolution of a Primate-Specific microRNA Family,weblink Molecular Biology and Evolution, 25, 7, 1493–1502, 10.1093/molbev/msn094, 0737-4038, 18417486, 2015-04-27,
  • JOURNAL, Willoughby, Pamela R., 2005, Palaeoanthropology and the Evolutionary Place of Humans in Nature,weblink International Journal of Comparative Psychology, 18, 1, 60–91, 0889-3667, 2015-04-27,
  • {{harvnb|Martin|2001|pp=12032–12038}}
  • JOURNAL, Tavaré, Simon, Simon Tavaré, Marshall, Charles R., Will, Oliver, Soligo, Christophe, Martin, Robert D., Robert D. Martin, 3, April 18, 2002, Using the fossil record to estimate the age of the last common ancestor of extant primates, Nature, 416, 6882, 726–729, 10.1038/416726a, 0028-0836, 11961552, 2002Natur.416..726T, One of the oldest known primate-like mammal species, the Plesiadapis, came from North America;JOURNAL, Rose, Kenneth D., 1994, The earliest primates, Evolutionary Anthropology: Issues, News, and Reviews, 3, 5, 159–173, 10.1002/evan.1360030505, 1060-1538, WEB,weblink Primate Evolution, Fleagle, John, John G. Fleagle, Gilbert, Chris, 2011, Rowe, Noel, Myers, Marc, All The World's Primates, Primate Conservation, Inc., Charlestown, RI, 2015-04-27, NEWS, Roach, John, March 3, 2008, Oldest Primate Fossil in North America Discovered,weblink National Geographic News, Washington, DC, National Geographic Society, 2015-04-27, NEWS, McMains, Vanessa, December 5, 2011, Found in Wyoming: New fossils of oldest American primate,weblink The Gazette, Baltimore, MD, Johns Hopkins University, 2015-04-27, NEWS, Caldwell, Sara B., May 19, 2009, Missing link found, early primate fossil 47 million years old,weblink Digital Journal, Toronto, Canada,, 2015-04-27, NEWS, Watts, Alex, May 20, 2009, Scientists Unveil Missing Link In Evolution,weblink Sky News, Sky News Online, London, Sky (United Kingdom), BSkyB,weblink" title="">weblink 2011-07-28, 2015-04-27, another, Archicebus, came from China.NEWS, Wilford, J.N., Palm-size fossil resets primates' clock, scientists say,weblink June 5, 2013, The New York Times, June 5, 2013, Other similar basal primates were widespread in Eurasia and Africa during the tropical conditions of the Paleocene and Eocene.
File:Notharctus tenebrosus AMNH.jpg|thumb|Notharctus tenebrosus, American Museum of Natural History, New York City, New York, US.]]David R. Begun JOURNAL, Kordos, László, Begun, David R., January 2001, Primates from Rudabánya: allocation of specimens to individuals, sex and age categories, Journal of Human Evolution, 40, 1, 17–39, 10.1006/jhev.2000.0437, 0047-2484, 11139358, concluded that early primates flourished in Eurasia and that a lineage leading to the African apes and humans, including to Dryopithecus, migrated south from Europe or Western Asia into Africa. The surviving tropical population of primates—which is seen most completely in the Upper Eocene and lowermost Oligocene fossil beds of the Faiyum depression southwest of Cairo—gave rise to all extant primate species, including the lemurs of Madagascar, lorises of Southeast Asia, galagos or "bush babies" of Africa, and to the anthropoids, which are the Platyrrhines or New World monkeys, the Catarrhines or Old World monkeys, and the great apes, including humans and other hominids.The earliest known catarrhine is Kamoyapithecus from uppermost Oligocene at Eragaleit in the northern Great Rift Valley in Kenya, dated to 24 million years ago.{{harvnb|Cameron|2004|p=76}} Its ancestry is thought to be species related to Aegyptopithecus, Propliopithecus, and Parapithecus from the Faiyum, at around 35 million years ago.{{harvnb|Wallace|2004|p=240}} In 2010, Saadanius was described as a close relative of the last common ancestor of the crown catarrhines, and tentatively dated to 29–28 million years ago, helping to fill an 11-million-year gap in the fossil record.JOURNAL, Zalmout, Iyad S., Sanders, William J., William J. Sanders, MacLatchy, Laura M., Gunnell, Gregg F., Al-Mufarreh, Yahya A., Ali, Mohammad A., Nasser, Abdul-Azziz H., Al-Masari, Abdu M., Al-Sobhi, Salih A., Nadhra, Ayman O., Matari, Adel H., Wilson, Jeffrey A., Gingerich, Philip D., July 15, 2010, New Oligocene primate from Saudi Arabia and the divergence of apes and Old World monkeys, Nature, 466, 7304, 360–364, 2010Natur.466..360Z, 10.1038/nature09094, 0028-0836, 20631798, 3, File:Proconsul skeleton reconstitution (University of Zurich).JPG|thumb|Reconstructed tailless Proconsul skeleton]]In the Early Miocene, about 22 million years ago, the many kinds of arboreally adapted primitive catarrhines from East Africa suggest a long history of prior diversification. Fossils at 20 million years ago include fragments attributed to Victoriapithecus, the earliest Old World monkey. Among the genera thought to be in the ape lineage leading up to 13 million years ago are Proconsul, Rangwapithecus, Dendropithecus, Limnopithecus, Nacholapithecus, Equatorius, Nyanzapithecus, Afropithecus, Heliopithecus, and Kenyapithecus, all from East Africa.The presence of other generalized non-cercopithecids of Middle Miocene from sites far distant—Otavipithecus from cave deposits in Namibia, and Pierolapithecus and Dryopithecus from France, Spain and Austria—is evidence of a wide diversity of forms across Africa and the Mediterranean basin during the relatively warm and equable climatic regimes of the Early and Middle Miocene. The youngest of the Miocene hominoids, Oreopithecus, is from coal beds in Italy that have been dated to 9 million years ago.Molecular evidence indicates that the lineage of gibbons (family Hylobatidae) diverged from the line of great apes some 18–12 million years ago, and that of orangutans (subfamily Ponginae) diverged from the other great apes at about 12 million years; there are no fossils that clearly document the ancestry of gibbons, which may have originated in a so-far-unknown South East Asian hominoid population, but fossil proto-orangutans may be represented by Sivapithecus from India and Griphopithecus from Turkey, dated to around 10 million years ago.{{harvnb|Srivastava|2009|p=87}}

Divergence of the human clade from other great apes

File:Lucy-reconstruction.jpg|thumb|upright|A reconstruction of "Lucy", a female Australopithecus afarensis on exhibit in the National Museum of Natural History, Washington, D.C.Washington, D.C.Species close to the last common ancestor of gorillas, chimpanzees and humans may be represented by Nakalipithecus fossils found in Kenya and Ouranopithecus found in Greece. Molecular evidence suggests that between 8 and 4 million years ago, first the gorillas, and then the chimpanzees (genus Pan) split off from the line leading to the humans. Human DNA is approximately 98.4% identical to that of chimpanzees when comparing single nucleotide polymorphisms (see human evolutionary genetics). The fossil record, however, of gorillas and chimpanzees is limited; both poor preservation—rain forest soils tend to be acidic and dissolve bone—and sampling bias probably contribute to this problem.Other hominins probably adapted to the drier environments outside the equatorial belt; and there they encountered antelope, hyenas, dogs, pigs, elephants, horses, and others. The equatorial belt contracted after about 8 million years ago, and there is very little fossil evidence for the split—thought to have occurred around that time—of the hominin lineage from the lineages of gorillas and chimpanzees. The earliest fossils argued by some to belong to the human lineage are Sahelanthropus tchadensis (7 Ma) and Orrorin tugenensis (6 Ma), followed by Ardipithecus (5.5–4.4 Ma), with species Ar. kadabba and Ar. ramidus.It has been argued in a study of the life history of Ar. ramidus that the species provides evidence for a suite of anatomical and behavioral adaptations in very early hominins unlike any species of extant great ape.JOURNAL, Clark, G., Henneberg, M., The life history of Ardipithecus ramidus: a heterochronic model of sexual and social maturation, Anthropological Review, 78, 2, 109–132, June 2015,weblink 2015-07-22, 10.1515/anre-2015-0009, This study demonstrated affinities between the skull morphology of Ar. ramidus and that of infant and juvenile chimpanzees, suggesting the species evolved a juvenalised or paedomorphic craniofacial morphology via heterochronic dissociation of growth trajectories. It was also argued that the species provides support for the notion that very early hominins, akin to bonobos (Pan paniscus) the less aggressive species of the genus Pan, may have evolved via the process of self-domestication. Consequently, arguing against the so-called "chimpanzee referential model" the authors suggest it is no longer tenable to use common chimpanzee (Pan troglodytes) social and mating behaviors in models of early hominin social evolution. When commenting on the absence of aggressive canine morphology in Ar. ramidus and the implications this has for the evolution of hominin social psychology, they wrote:}}The authors argue that many of the basic human adaptations evolved in the ancient forest and woodland ecosystems of late Miocene and early Pliocene Africa. Consequently, they argue that humans may not represent evolution from a chimpanzee-like ancestor as has traditionally been supposed. This suggests many modern human adaptations represent phylogenetically deep traits and that the behavior and morphology of chimpanzees may have evolved subsequent to the split with the common ancestor they share with humans.

Genus Australopithecus

The genus Australopithecus evolved in eastern Africa around 4 million years ago before spreading throughout the continent and eventually becoming extinct 2 million years ago. During this time period various forms of australopiths existed, including Australopithecus anamensis, Au. afarensis, Au. sediba, and Au. africanus. There is still some debate among academics whether certain African hominid species of this time, such as Au. robustus and Au. boisei, constitute members of the same genus; if so, they would be considered to be Au. robust australopiths whilst the others would be considered Au. gracile australopiths. However, if these species do indeed constitute their own genus, then they may be given their own name, the Paranthropus. A new proposed species Australopithecus deyiremeda is claimed to have been discovered living at the same time period of Au. afarensis. There is debate if Au. deyiremeda is a new species or is Au. afarensis.NEWS, Zimmer, Carl, Carl Zimmer, May 27, 2015, The Human Family Tree Bristles With New Branches,weblink The New York Times, 2015-05-30, Australopithecus prometheus, otherwise known as Little Foot has recently been dated at 3.67 million years old through a new dating technique, making the genus Australopithecus as old as afarensis.Gardner., Elizabeth K.; Purdue University (April 1, 2015). "New instrument dates old skeleton before 'Lucy'; 'Little Foot' 3.67 million years old". Science Daily. Retrieved April 3, 2015. Given the opposable big toe found on Little Foot, it seems that he was a good climber, and it is thought given the night predators of the region, he probably, like gorillas and chimpanzees, built a nesting platform at night, in the trees.

Evolution of genus Homo

{{split section|Homo|date=April 2018}}The earliest documented representative of the genus Homo is Homo habilis, which evolved around {{Mya|2.8}},NEWS, Ghosh, Pallab, Pallab Ghosh, March 4, 2015, 'First human' discovered in Ethiopia,weblink BBC News, London, 2015-04-19, and is arguably the earliest species for which there is positive evidence of the use of stone tools. The brains of these early hominins were about the same size as that of a chimpanzee, although it has been suggested that this was the time in which the human SRGAP2 gene doubled, producing a more rapid wiring of the frontal cortex. During the next million years a process of rapid encephalization occurred, and with the arrival of Homo erectus and Homo ergaster in the fossil record, cranial capacity had doubled to 850 cm3.{{harvnb|Swisher|Curtis|Lewin|2001}} (Such an increase in human brain size is equivalent to each generation having 125,000 more neurons than their parents.) It is believed that Homo erectus and Homo ergaster were the first to use fire and complex tools, and were the first of the hominin line to leave Africa, spreading throughout Africa, Asia, and Europe between {{Mya|1.3|1.8}}.File:Homo lineage 2017update.svg|thumb|upright=1.4|A model of the evolution of the genus Homo over the last 2 million years (vertical axis). The rapid "Out of Africa" expansion of H. sapiens is indicated at the top of the diagram, with admixture indicated with Neanderthals, Denisovans, and unspecified archaic African hominins.Late survival of robust australopithecines (ParanthropusParanthropusFile:Homo sapiens lineage.svg|thumb|upright=1.4|A model of the phylogeny of H. sapiens during the Middle Paleolithic. The horizontal axis represents geographic location; the vertical axis represents time in thousands of years ago.based onSchlebusch et al., "Southern African ancient genomes estimate modern human divergence to 350,000 to 260,000 years ago" Science, 28 Sep 2017, {{doi|10.1126/science.aao6266}}, Fig. 3 (H. sapiens divergence times) and JOURNAL, Stringer, C., What makes a modern human, Nature, 2012, 485, 7396, 33–35, 10.1038/485033a, 22552077, 2012Natur.485...33S, (archaic admixture).Homo heidelbergensis is shown as diverging into Neanderthals, Denisovans and H. sapiens. With the expansion of H. sapiens after 200 kya, Neanderthals, Denisovans and unspecified archaic African hominins are shown as again subsumed into the H. sapiens lineage. In addition, admixture events in modern African populations are indicated.]]According to the recent African origin of modern humans theory, modern humans evolved in Africa possibly from Homo heidelbergensis, Homo rhodesiensis or Homo antecessor and migrated out of the continent some 50,000 to 100,000 years ago, gradually replacing local populations of Homo erectus, Denisova hominins, Homo floresiensis, Homo luzonensis and Homo neanderthalensis.{{harvnb|Stringer|1994|p=242}}{{harvnb|McHenry|2009|p=265}}JOURNAL, Out of Africa Revisited, May 13, 2005, Science (journal), Science, This Week in Science, 308, 5724, 921, 10.1126/science.308.5724.921g, 0036-8075, JOURNAL, Stringer, Chris, Chris Stringer, June 12, 2003, Human evolution: Out of Ethiopia, Nature (journal), Nature, 423, 6941, 692–695, 10.1038/423692a, 0028-0836, 12802315, 2003Natur.423..692S, WEB,weblink Origins of Modern Humans: Multiregional or Out of Africa?, Johanson, Donald, Donald Johanson, May 2001, actionbioscience, American Institute of Biological Sciences, Washington, DC, 2009-11-23, Archaic Homo sapiens, the forerunner of anatomically modern humans, evolved in the Middle Paleolithic between 400,000 and 250,000 years ago.PRESS RELEASE, Mixon, Bobbie, Ehardt, Carolyn, Hammer, Michael, September 6, 2011, Evolution's Past Is Modern Human's Present,weblink National Science Foundation, Press Release 11-181, 2015-04-20, WEB,weblink Early Modern Homo sapiens, O'Neil, Dennis, Evolution of Modern Humans: A Survey of the Biological and Cultural Evolution of Archaic and Modern Homo sapiens, Palomar College, San Marcos, CA, Tutorial, 2015-04-20, JOURNAL, Fossil Reanalysis Pushes Back Origin of Homo sapiens,weblink February 17, 2005, Scientific American, 0036-8733, 2015-04-20, Recent DNA evidence suggests that several haplotypes of Neanderthal origin are present among all non-African populations, and Neanderthals and other hominins, such as Denisovans, may have contributed up to 6% of their genome to present-day humans, suggestive of a limited inter-breeding between these species.JOURNAL, Reich, David, David Reich (geneticist), Green, Richard E., Kircher, Martin, Krause, Patterson, Durand, Viola, Briggs, Stenzel, Johnson, Maricic, Good, Marques-Bonet, Alkan, Fu, Mallick, Li, Meyer, Eichler, Stoneking, Richards, Talamo, Shunkov, Derevianko, Hublin, Kelso, Slatkin, Pääbo, 3, December 23, 2010, Genetic history of an archaic hominin group from Denisova Cave in Siberia, Nature, 468, 7327, 1053–1060, 2010Natur.468.1053R, 10.1038/nature09710, 0028-0836, 21179161, 4306417, 10230/25596, JOURNAL, Noonan, James P., May 2010, Neanderthal genomics and the evolution of modern humans, Genome Research, 20, 5, 547–553, 10.1101/gr.076000.108, 1088-9051, 2860157, 20439435, JOURNAL, Abi-Rached, Laurent, Jobin, Matthew J., Kulkarni, Subhash, McWhinnie, A., Dalva, K., Gragert, L., Babrzadeh, F., Gharizadeh, B., Luo, M., Plummer, F.A., Kimani, J., Carrington, M., Middleton, D., Rajalingam, R., Beksac, M., Marsh, S.G.E., Maiers, M., Guethlein, L.A., Tavoularis, S., Little, A.-M., Green, R.E., Norman, P.J., Parham, P., 3, October 7, 2011, The Shaping of Modern Human Immune Systems by Multiregional Admixture with Archaic Humans, Science, 334, 6052, 89–94, 2011Sci...334...89A, 10.1126/science.1209202, 0036-8075, 3677943, 21868630, The transition to behavioral modernity with the development of symbolic culture, language, and specialized lithic technology happened around 50,000 years ago according to some anthropologistsJOURNAL, Mellars, Paul Mellars, Paul, June 20, 2006, Why did modern human populations disperse from Africa ca. 60,000 years ago? A new model, Proceedings of the National Academy of Sciences, Proc. Natl. Acad. Sci. U.S.A., 103, 25, 9381–9386, 2006PNAS..103.9381M, 10.1073/pnas.0510792103, 0027-8424, 1480416, 16772383, although others point to evidence that suggests that a gradual change in behavior took place over a longer time span.JOURNAL, Mcbrearty, Sally, Brooks, Alison S., November 2000, The revolution that wasn't: a new interpretation of the origin of modern human behavior, Journal of Human Evolution, 39, 5, 453–563, 10.1006/jhev.2000.0435, 0047-2484, 11102266, Homo sapiens is the only extant species of its genus, Homo. While some (extinct) Homo species might have been ancestors of Homo sapiens, many, perhaps most, were likely "cousins", having speciated away from the ancestral hominin line.JOURNAL, Strait, David S., Grine, Frederick E., Frederick E. Grine, Moniz, Marc A., January 1997, A reappraisal of early hominid phylogeny, Journal of Human Evolution, 32, 1, 17–82, 10.1006/jhev.1996.0097, 0047-2484, 9034954, {{harvnb|Bryson|2004|pp=522–543}} There is yet no consensus as to which of these groups should be considered a separate species and which should be a subspecies; this may be due to the dearth of fossils or to the slight differences used to classify species in the genus Homo. The Sahara pump theory (describing an occasionally passable "wet" Sahara desert) provides one possible explanation of the early variation in the genus Homo.Based on archaeological and paleontological evidence, it has been possible to infer, to some extent, the ancient dietary practices of various Homo species and to study the role of diet in physical and behavioral evolution within Homo.{{harvnb|Walker|2007|pp=3–10}}{{harvnb|Ungar|Teaford|2002}}{{harvnb|Bogin|1997|pp=weblink" title="">96–142}}JOURNAL, Barnicot, Nigel A., April–June 2005, Human nutrition: Evolutionary perspectives, Integrative Physiological & Behavioral Science, 40, 2, 114–117, 10.1007/BF02734246, 1932-4502, 17393680, Some anthropologists and archaeologists subscribe to the Toba catastrophe theory, which posits that the supereruption of Lake Toba on Sumatran island in Indonesia some 70,000 years ago caused global consequences,NEWS, The new batch – 150,000 years ago,weblink The evolution of man, London, BBC Science & Nature,weblink" title="">weblink 2006-01-18, 2015-04-28, killing the majority of humans and creating a population bottleneck that affected the genetic inheritance of all humans today.NEWS, Whitehouse, David, June 9, 2003, When humans faced extinction,weblink BBC News, London, BBC, 2007-01-05, The genetic and archaeological evidence for this remains in question however.WEB,weblink Modern humans flourished through ancient supervolcano eruption 74,000 years ago: Modern humans flourished through ancient supervolcano eruption, ScienceDaily, en, 2019-01-24,

H. habilis and H. gautengensis

Homo habilis lived from about 2.8 to 1.4 Ma. The species evolved in South and East Africa in the Late Pliocene or Early Pleistocene, 2.5–2 Ma, when it diverged from the australopithecines. Homo habilis had smaller molars and larger brains than the australopithecines, and made tools from stone and perhaps animal bones. One of the first known hominins was nicknamed 'handy man' by discoverer Louis Leakey due to its association with stone tools. Some scientists have proposed moving this species out of Homo and into Australopithecus due to the morphology of its skeleton being more adapted to living on trees rather than to moving on two legs like Homo sapiens.JOURNAL, Wood, Bernard, Collard, Mark, 1999, The changing face of Genus Homo, Evolutionary Anthropology: Issues, News, and Reviews, 8, 6, 195–207, 10.1002/(SICI)1520-6505(1999)8:63.0.CO;2-2, 1060-1538, In May 2010, a new species, Homo gautengensis, was discovered in South Africa.NEWS, Viegas, Jennifer, May 21, 2010, Toothy Tree-Swinger May Be Earliest Human,weblink Discovery Channel, Discovery News, Silver Spring, MD, Discovery Communications, Discovery Communications, LLC., 2015-04-28,

H. rudolfensis and H. georgicus

These are proposed species names for fossils from about 1.9–1.6 Ma, whose relation to Homo habilis is not yet clear.
  • Homo rudolfensis refers to a single, incomplete skull from Kenya. Scientists have suggested that this was another Homo habilis, but this has not been confirmed.JOURNAL, Wood, Bernard A., January 1999, Homo rudolfensis Alexeev, 1986 – fact or phantom?, Journal of Human Evolution, 36, 1, 115–118, 10.1006/jhev.1998.0246, 0047-2484, 9924136,
  • Homo georgicus, from Georgia, may be an intermediate form between Homo habilis and Homo erectus,JOURNAL, Gabounia, Léo, de Lumley, Marie-Antoinette, Vekua, Abesalom, Lordkipanidze, David, de Lumley, Henry, September 2002, Découverte d'un nouvel hominidé à Dmanissi (Transcaucasie, Géorgie), Discovery of a new hominid at Dmanisi (Transcaucasia, Georgia), Comptes Rendus Palevol, French, 1, 4, 243–253, 10.1016/S1631-0683(02)00032-5, 1631-0683, 3, or a sub-species of Homo erectus.JOURNAL, Lordkipanidze, David, David Lordkipanidze, Vekua, Abesalom, Ferring, Reid, Rightmire, G. Philip, Zollikofer, Christoph P.E., Ponce de León, Marcia S., Agusti, Jordi, Kiladze, Gocha, Mouskhelishvili, Alexander, Nioradze, Medea, Tappen, Martha, November 2006, A fourth hominin skull from Dmanisi, Georgia, (The Anatomical Record, The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology), 288A, 11, 1146–1157, 10.1002/ar.a.20379, 1552-4884, 17031841, 3,

H. ergaster and H. erectus

The first fossils of Homo erectus were discovered by Dutch physician Eugene Dubois in 1891 on the Indonesian island of Java. He originally named the material Anthropopithecus erectus (1892–1893, considered at this point as a chimpanzee-like fossil primate) and Pithecanthropus erectus (1893–1894, changing his mind as of based on its morphology, which he considered to be intermediate between that of humans and apes).JOURNAL, Turner, William, William Turner Thiselton-Dyer, April 1895, On M. Dubois' Description of Remains recently found in Java, named by him Pithecanthropus erectus. With Remarks on so-called Transitional Forms between Apes and Man, Journal of Anatomy, Journal of Anatomy and Physiology, 29, Pt 3, 424–445, 1328414, 17232143, Years later, in the 20th century, the German physician and paleoanthropologist Franz Weidenreich (1873–1948) compared in detail the characters of Dubois' Java Man, then named Pithecanthropus erectus, with the characters of the Peking Man, then named Sinanthropus pekinensis. Weidenreich concluded in 1940 that because of their anatomical similarity with modern humans it was necessary to gather all these specimens of Java and China in a single species of the genus Homo, the species Homo erectus.{{citation needed|date=May 2018}} Homo erectus lived from about 1.8 Ma to about 70,000 years ago—which would indicate that they were probably wiped out by the Toba catastrophe; however, nearby Homo floresiensis survived it. The early phase of Homo erectus, from 1.8 to 1.25 Ma, is considered by some to be a separate species, Homo ergaster, or as Homo erectus ergaster, a subspecies of Homo erectus.In Africa in the Early Pleistocene, 1.5–1 Ma, some populations of Homo habilis are thought to have evolved larger brains and to have made more elaborate stone tools; these differences and others are sufficient for anthropologists to classify them as a new species, Homo erectus—in Africa.JOURNAL, Spoor, Fred, Wood, Bernard A., Zonneveld, Frans, June 23, 1994, Implications of early hominid labyrinthine morphology for evolution of human bipedal locomotion, Nature, 369, 6482, 645–648, 1994Natur.369..645S, 10.1038/369645a0, 0028-0836, 8208290, The evolution of locking knees and the movement of the foramen magnum are thought to be likely drivers of the larger population changes. This species also may have used fire to cook meat. (Catching Fire: How Cooking Made Us Human|Richard Wrangham) suggests that the fact that Homo seems to have been ground dwelling, with reduced intestinal length, smaller dentition, "and swelled our brains to their current, horrendously fuel-inefficient size",NEWSPAPER,weblink Catching Fire: How Cooking Made Us Human by Richard Wrangham: review, February 23, 2016, 2009-10-04, Ings, Simon, suggest that control of fire and releasing increased nutritional value through cooking was the key adaptation that separated Homo from tree-sleeping Australopithecines.Wrangham, Richard (2011), "Catching Fire: How cooking made us human"{{See also|Control of fire by early humans}}A famous example of Homo erectus is Peking Man; others were found in Asia (notably in Indonesia), Africa, and Europe. Many paleoanthropologists now use the term Homo ergaster for the non-Asian forms of this group, and reserve Homo erectus only for those fossils that are found in Asia and meet certain skeletal and dental requirements which differ slightly from H. ergaster.

H. cepranensis and H. antecessor

These are proposed as species that may be intermediate between H. erectus and H. heidelbergensis.
  • H. antecessor is known from fossils from Spain and England that are dated 1.2 Ma–500 ka.JOURNAL, Bermúdez de Castro, José María, Arsuaga, Juan Luis, Juan Luis Arsuaga, Carbonell, Eudald, Eudald Carbonell, Rosas, Antonio, Martínez, I, Mosquera, Marina, May 30, 1997, A Hominid from the Lower Pleistocene of Atapuerca, Spain: Possible Ancestor to Neandertals and Modern Humans, Science, 276, 5317, 1392–1395, 10.1126/science.276.5317.1392, 0036-8075, 9162001, 3, JOURNAL, Carbonell, Eudald, Bermúdez de Castro, José María, Parés, Josep M., Pérez-González, A, Cuenca-Bescós, G, Ollé, A, Mosquera, M, Huguet, R, Van Der Made, J, Rosas, A, Sala, R, Vallverdú, J, García, N, Granger, D.E., Martinón-Torres, M, Rodríguez, X.P., Stock, G.M., Vergès, J.M., Allué, E, Burjachs, F, Cáceres, I, Canals, A, Benito, A, Díez, C, Lozano, M, Mateos, A, Navazo, M, Rodríguez, J, Rosell, J, Arsuaga, J.L., March 27, 2008, The first hominin of Europe, Nature, 452, 7186, 465–469, 2008Natur.452..465C, 10.1038/nature06815, 0028-0836, 18368116, 3, 2027.42/62855,
  • H. cepranensis refers to a single skull cap from Italy, estimated to be about 800,000 years old.JOURNAL, Manzi, Giorgio, Mallegni, Francesco, Francesco Mallegni, Ascenzi, Antonio, August 14, 2001, A cranium for the earliest Europeans: Phylogenetic position of the hominid from Ceprano, Italy, Proc. Natl. Acad. Sci. U.S.A., 98, 17, 10011–10016, 2001PNAS...9810011M, 10.1073/pnas.151259998, 0027-8424, 55569, 11504953,

H. heidelbergensis

H. heidelbergensis ("Heidelberg Man") lived from about 800,000 to about 300,000 years ago. Also proposed as Homo sapiens heidelbergensis or Homo sapiens paleohungaricus.JOURNAL, Czarnetzki, Alfred, Jakob, Tina, Pusch, Carsten M., April 2003, Palaeopathological and variant conditions of the Homo heidelbergensis type specimen (Mauer, Germany), Journal of Human Evolution, 44, 4, 479–495, 10.1016/S0047-2484(03)00029-0, 0047-2484, 12727464,

H. rhodesiensis, and the Gawis cranium

  • H. rhodesiensis, estimated to be 300,000–125,000 years old. Most current researchers place Rhodesian Man within the group of Homo heidelbergensis, though other designations such as archaic Homo sapiens and Homo sapiens rhodesiensis have been proposed.
  • In February 2006 a fossil, the Gawis cranium, was found which might possibly be a species intermediate between H. erectus and H. sapiens or one of many evolutionary dead ends. The skull from Gawis, Ethiopia, is believed to be 500,000–250,000 years old. Only summary details are known, and the finders have not yet released a peer-reviewed study. Gawis man's facial features suggest its being either an intermediate species or an example of a "Bodo man" female.PRESS RELEASE, Semaw, Sileshi, Toth, Nicholas, Schick, Kathy, Simpson, Scott, Quade, Jay, Rogers, Michael J., March 27, 2006, Scientists discover hominid cranium in Ethiopia,weblink Bloomington, Indiana University, 2006-11-26, 3,

Neanderthal and Denisovan

File:Homo heidelbergensis (10233446).jpg|thumb|upright|Reconstruction of Homo heidelbergensis which may be the direct ancestor of both Homo neanderthalensis and Homo sapiens.]]Homo neanderthalensis, alternatively designated as Homo sapiens neanderthalensis,JOURNAL, Harvati, Katerina, January 2003, The Neanderthal taxonomic position: models of intra- and inter-specific craniofacial variation, Journal of Human Evolution, 44, 1, 107–132, 10.1016/S0047-2484(02)00208-7, 0047-2484, 12604307, lived in Europe and Asia from 400,000JOURNAL, Herrera, K.J., Somarelli, J.A., Lowery, R.K., Herrera, R.J., To what extent did Neanderthals and modern humans interact?, 2009, Biological Reviews, 84, 2, 245–257, 10.1111/j.1469-185X.2008.00071.x, 19391204, to about 28,000 years ago.JOURNAL, 10.1038/nature05195, 16971951, Late survival of Neanderthals at the southernmost extreme of Europe, Nature, 443, 7113, 850–853, 2006, Finlayson, Clive, Giles Pacheco, Francisco, Rodríguez-Vidal, Joaquín, Fa, Darren A, María Gutierrez López, José, Santiago Pérez, Antonio, Finlayson, Geraldine, Allue, Ethel, Baena Preysler, Javier, Cáceres, Isabel, Carrión, José S, Fernández Jalvo, Yolanda, Gleed-Owen, Christopher P, Jimenez Espejo, Francisco J, López, Pilar, Antonio López Sáez, José, Antonio Riquelme Cantal, José, Sánchez Marco, Antonio, Giles Guzman, Francisco, Brown, Kimberly, Fuentes, Noemí, Valarino, Claire A, Villalpando, Antonio, Stringer, Christopher B, Martinez Ruiz, Francisca, Sakamoto, Tatsuhiko, 2006Natur.443..850F, 10261/18685, There are a number of clear anatomical differences between anatomically modern humans (AMH) and Neanderthal populations. Many of these relate to the superior adaptation to cold environments possessed by the Neanderthal populations. Their surface to volume ratio is an extreme version of that found amongst Inuit populations, indicating that they were less inclined to lose body heat than were AMH. From brain Endocasts, Neanderthals also had significantly larger brains. This would seem to indicate that the intellectual superiority of AMH populations may be questionable. More recent research by Eiluned Pearce, Chris Stringer, R.I.M. Dunbar, however, have shown important differences in Brain architecture. For example, in both the orbital chamber size and in the size of the occipital lobe, the larger size suggests that the Neanderthal had a better visual acuity than modern humans. This would give a superior vision in the inferior light conditions found in Glacial Europe. It also seems that the higher body mass of Neanderthals had a correspondingly larger brain mass required for body care and control.JOURNAL, Eiluned, Pearce, Chris, Stringer, R.I.M., Dunbar, 2013, New insights into differences in brain organization between Neanderthals and anatomically modern humans (Proceedings of the Royal Society), Proceedings of the Royal Society of London B: Biological Sciences, 280, 1758, 20130168, 10.1098/rspb.2013.0168, 23486442, 3619466, The Neanderthal populations seem to have been physically superior to AMH populations. These differences may have been sufficient to give Neanderthal populations an environmental superiority to AMH populations from 75,000 to 45,000 years BP. With these differences, Neanderthal brains show a smaller area was available for social functioning. Plotting group size possible from endocrainial volume, suggests that AMH populations (minus occipital lobe size), had a Dunbars number of 144 possible relationships. Neanderthal populations seem to have been limited to about 120 individuals. This would show up in a larger number of possible mates for AMH humans, with increased risks of inbreeding amongst Neanderthal populations. It also suggests that humans had larger trade catchment areas than Neanderthals (confirmed in the distribution of stone tools). With larger populations, social and technological innovations were easier to fix in human populations, which may have all contributed to the fact that modern Homo sapiens replaced the Neanderthal populations by 28,000 BP.(File:Neandertaler reconst.jpg|upright|thumb|Dermoplastic reconstruction of a Neanderthal)Earlier evidence from sequencing mitochondrial DNA suggested that no significant gene flow occurred between H. neanderthalensis and H. sapiens, and that the two were separate species that shared a common ancestor about 660,000 years ago.JOURNAL, Krings, Matthias, Stone, Anne, Schmitz, Ralf W., Krainitzki, Heike, Stoneking, Mark, Pääbo, Svante, July 11, 1997, Neandertal DNA sequences and the origin of modern humans, Cell (journal), Cell, 90, 1, 19–30, 10.1016/S0092-8674(00)80310-4, 0092-8674, 9230299, 3, JOURNAL, Green, Richard E., Malaspinas, Anna-Sapfo, Krause, Johannes, Briggs, Adrian W., Johnson, Philip L.F., Uhler, Caroline, Meyer, Matthias, Good, Jeffrey M., Maricic, Tomislav, Stenzel, Udo, Prüfer, Kay, Siebauer, Michael, Burbano, Hernán A., Ronan, Michael, Rothberg, Jonathan M., Egholm, Michael, Rudan, Pavao, Brajković, Dejana, Kućan, Željko, Gušić, Ivan, Wikström, Mårten, Laakkonen, Liisa, Kelso, Janet, Slatkin, Montgomery, Pääbo, Svante, August 8, 2008, A Complete Neandertal Mitochondrial Genome Sequence Determined by High-Throughput Sequencing, Cell, 134, 3, 416–426, 10.1016/j.cell.2008.06.021, 0092-8674, 2602844, 18692465, 3, JOURNAL, Serre, David, Langaney, André, Chech, Mario, Teschler-Nicola, Paunovic, Mennecier, Hofreiter, Possnert, Pääbo, March 2004, No Evidence of Neandertal mtDNA Contribution to Early Modern Humans, PLOS Biology, 2, 3, e57, 10.1371/journal.pbio.0020057, 1545-7885, 368159, 15024415, 3, However, a sequencing of the Neanderthal genome in 2010 indicated that Neanderthals did indeed interbreed with anatomically modern humans circa 45,000 to 80,000 years ago (at the approximate time that modern humans migrated out from Africa, but before they dispersed into Europe, Asia and elsewhere).NEWS, Viegas, Jennifer, May 6, 2010, Neanderthals, Humans Interbred, DNA Proves,weblink Discovery News, Silver Spring, MD, Discovery Communications, LLC., 2015-04-30,weblink" title="">weblink May 8, 2015, dead, mdy-all, The genetic sequencing of a 40,000 year old human skeleton from Romania showed that 11% of its genome was Neanderthal, and it was estimated that the individual had a Neanderthal ancestor 4–6 generations previously,JOURNAL, Calloway, Ewan, Early European may have had Neanderthal great-great-grandparent, Nature, 13 May 2015,weblink in addition to a contribution from earlier interbreeding in the Middle East. Though this interbred Romanian population seems not to have been ancestral to modern humans, the finding indicates that interbreeding happened repeatedly.NEWS, Sample, Ian, My Neanderthal sex secret: modern European's great-great grandparent link, The Guardian, 22 June 2015, 27 July 2018,weblink Nearly all modern non-African humans have 1% to 4% of their DNA derived from Neanderthal DNA, and this finding is consistent with recent studies indicating that the divergence of some human alleles dates to one Ma, although the interpretation of these studies has been questioned.JOURNAL, Gutiérrez, Gabriel, Sánchez, Diego, Marín, Antonio, August 2002, A Reanalysis of the Ancient Mitochondrial DNA Sequences Recovered from Neandertal Bones, Molecular Biology and Evolution, 19, 8, 1359–1366, 10.1093/oxfordjournals.molbev.a004197, 0737-4038, 12140248, JOURNAL, Hebsgaard, Martin B., Wiuf, Carsten, Gilbert, M. Thomas, Glenner, Henrik, Willerslev, Eske, January 2007, Evaluating Neanderthal Genetics and Phylogeny, Journal of Molecular Evolution, 64, 1, 50–60, 10.1007/s00239-006-0017-y, 0022-2844, 17146600, 3,weblinkweblink" title="">weblink dead, 2011-04-01, 2017-10-24,, Neanderthals and Homo sapiens could have co-existed in Europe for as long as 10,000 years, during which human populations exploded vastly outnumbering Neanderthals, possibly outcompeting them by sheer numerical strength.JOURNAL, Mellars, Paul, French, Jennifer C., July 29, 2011, Tenfold Population Increase in Western Europe at the Neandertal–to–Modern Human Transition Paul, Science, 333, 6042, 623–627, 2011Sci...333..623M, 10.1126/science.1206930, 0036-8075, 21798948, In 2008, archaeologists working at the site of Denisova Cave in the Altai Mountains of Siberia uncovered a small bone fragment from the fifth finger of a juvenile member of Denisovans.JOURNAL, Brown, Terence A., April 8, 2010, Human evolution: Stranger from Siberia, Nature, 464, 7290, 838–839, 2010Natur.464..838B, 10.1038/464838a, 0028-0836, 20376137, Artifacts, including a bracelet, excavated in the cave at the same level were carbon dated to around 40,000 BP. As DNA had survived in the fossil fragment due to the cool climate of the Denisova Cave, both mtDNA and nuclear DNA were sequenced.JOURNAL, Krause, Johannes, Qiaomei Fu, Good, Jeffrey M., Viola, Bence, Shunkov, Michael V., Derevianko, Anatoli P., Pääbo, Svante, April 8, 2010, The complete mitochondrial DNA genome of an unknown hominin from southern Siberia, Nature, 464, 7290, 894–897, 2010Natur.464..894K, 10.1038/nature08976, 0028-0836, 20336068, 3, While the divergence point of the mtDNA was unexpectedly deep in time,NEWS, Katsnelson, Alla, March 24, 2010, New hominin found via mtDNA,weblink The Nutshell, Blog, Philadelphia, PA, The Scientist (magazine), The Scientist, 0890-3670, 2015-05-01, the full genomic sequence suggested the Denisovans belonged to the same lineage as Neanderthals, with the two diverging shortly after their line split from the lineage that gave rise to modern humans. Modern humans are known to have overlapped with Neanderthals in Europe and the Near East for possibly more than 40,000 years,"Kaufman, Danial (2002), "Comparisons and the Case for Interaction among Neanderthals and Early Modern Humans in the Levant" (Oxford Journal of Anthropology) and the discovery raises the possibility that Neanderthals, Denisovans, and modern humans may have co-existed and interbred. The existence of this distant branch creates a much more complex picture of humankind during the Late Pleistocene than previously thought.JOURNAL, Bokma, Folmer, van den Brink, Valentijn, Stadler, Tanja, September 2012, Unexpectedly many extinct hominins, Evolution (journal), Evolution, 66, 9, 2969–2974, 10.1111/j.1558-5646.2012.01660.x, 0014-3820, 22946817, Evidence has also been found that as much as 6% of the DNA of some modern Melanesians derive from Denisovans, indicating limited interbreeding in Southeast Asia.JOURNAL, Martinón-Torres, María, Dennell, Robin, Bermúdez de Castro, José María, February 2011, The Denisova hominin need not be an out of Africa story, Journal of Human Evolution, 60, 2, 251–255, 10.1016/j.jhevol.2010.10.005, 0047-2484, 21129766, Alleles thought to have originated in Neanderthals and Denisovans have been identified at several genetic loci in the genomes of modern humans outside of Africa. HLA haplotypes from Denisovans and Neanderthal represent more than half the HLA alleles of modern Eurasians, indicating strong positive selection for these introgressed alleles. Corinne Simoneti at Vanderbilt University, in Nashville and her team have found from medical records of 28,000 people of European descent that the presence of Neanderthal DNA segments may be associated with a likelihood to suffer depression more frequently.JOURNAL, 10.1126/science.aad2149, 26912863, 4849557, The phenotypic legacy of admixture between modern humans and Neandertals, Science, 351, 6274, 737–741, 2016, Simonti, C.N., Vernot, B., Bastarache, L., Bottinger, E., Carrell, D.S., Chisholm, R.L., Crosslin, D.R., Hebbring, S.J., Jarvik, G. P., Kullo, I.J., Li, R., Pathak, J., Ritchie, M.D., Roden, D.M., Verma, S.S., Tromp, G., Prato, J.D., Bush, W.S., Akey, J.M., Denny, J.C., Capra, J.A., The flow of genes from Neanderthal populations to modern human was not all one way. Sergi Castellano of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has in 2016 reported that while Denisovan and Neanderthal genomes are more related to each other than they are to us, Siberian Neanderthal genomes show similarity to the modern human gene pool, more so than to European Neanderthal populations. The evidence suggests that the Neanderthal populations interbred with modern humans possibly 100,000 years ago, probably somewhere in the Near East.JOURNAL, 10.1038/nature16544, 530, 7591, Ancient gene flow from early modern humans into Eastern Neanderthals, Nature, 429–433, 26886800, 4933530, Kuhlwilm, M, Gronau, I, Hubisz, MJ, de Filippo, C, Prado-Martinez, J, Kircher, M, Fu, Q, Burbano, HA, Lalueza-Fox, C, de la Rasilla, M, Rosas, A, Rudan, P, Brajkovic, D, Kucan, Ž, Gušic, I, Marques-Bonet, T, Andrés, AM, Viola, B, Pääbo, S, Meyer, M, Siepel, A, Castellano, S, 2016Natur.530..429K, 2016, Studies of a Neanderthal child at Gibraltar show from brain development and teeth eruption that Neanderthal children may have matured more rapidly than is the case for Homo sapiens.Dean, MC, Stringer, CB et al, (1986) "Age at death of the Neanderthal child from Devil's Tower, Gibraltar and the implications for studies of general growth and development in Neanderthals" (American Journal of Physical Anthropology, Vol 70 Issue 3, July 1986)

H. floresiensis

H. floresiensis, which lived from approximately 190,000 to 50,000 years before present (BP), has been nicknamed hobbit for its small size, possibly a result of insular dwarfism.JOURNAL, Brown, Peter, Sutikna, Thomas, Morwood, Michael J., Mike Morwood, Soejono, Raden Panji, Raden Panji Soejono, Jatmiko, Ako, Wayhu Saptomo, E., Awe Due, Rokus, October 28, 2004, A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia, Nature, 431, 7012, 1055–1061, 2004Natur.431.1055B, 10.1038/nature02999, 0028-0836, 15514638, 4, H. floresiensis is intriguing both for its size and its age, being an example of a recent species of the genus Homo that exhibits derived traits not shared with modern humans. In other words, H. floresiensis shares a common ancestor with modern humans, but split from the modern human lineage and followed a distinct evolutionary path. The main find was a skeleton believed to be a woman of about 30 years of age. Found in 2003, it has been dated to approximately 18,000 years old. The living woman was estimated to be one meter in height, with a brain volume of just 380 cm3 (considered small for a chimpanzee and less than a third of the H. sapiens average of 1400 cm3). {{Citation needed|date=April 2012}}However, there is an ongoing debate over whether H. floresiensis is indeed a separate species.JOURNAL, Argue, Debbie, Donlon, Denise, Groves, Colin, Colin Groves, Wright, Richard, October 2006, Homo floresiensis: Microcephalic, pygmoid, Australopithecus, or Homo?, Journal of Human Evolution, 51, 4, 360–374, 10.1016/j.jhevol.2006.04.013, 0047-2484, 16919706, 3, Some scientists hold that H. floresiensis was a modern H. sapiens with pathological dwarfism.JOURNAL, Martin, Robert D., Robert D. Martin, Maclarnon, Ann M., Phillips, James L., Dobyns, William B., November 2006, Flores hominid: New species or microcephalic dwarf?, The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology, 288A, 11, 1123–1145, 10.1002/ar.a.20389, 1552-4884, 17031806, 3, This hypothesis is supported in part, because some modern humans who live on Flores, the Indonesian island where the skeleton was found, are pygmies. This, coupled with pathological dwarfism, could have resulted in a significantly diminutive human. The other major attack on H. floresiensis as a separate species is that it was found with tools only associated with H. sapiens.The hypothesis of pathological dwarfism, however, fails to explain additional anatomical features that are unlike those of modern humans (diseased or not) but much like those of ancient members of our genus. Aside from cranial features, these features include the form of bones in the wrist, forearm, shoulder, knees, and feet. Additionally, this hypothesis fails to explain the find of multiple examples of individuals with these same characteristics, indicating they were common to a large population, and not limited to one individual.{{Citation needed|date=September 2015}}

H. luzonensis

A small number of specimens from the island of Luzon, dated 50,000 to 67,000 years ago, have recently been assigned by their discoverers, based on dental characteristics, to a novel human species, H. luzonensis.JOURNAL, Détroit, F., Mijares, A. S., Corny, J., Daver, G., Zanolli, C., Dizon, E., Robles, E., Grün, R., Piper, P. J., yes, 2019, A new species of Homo from the Late Pleistocene of the Philippines, Nature, 568, 7751, 181–186, 10.1038/s41586-019-1067-9, 30971845,

H. sapiens

H. sapiens (the adjective (wikt:sapiens|sapiens) is Latin for "wise" or "intelligent") emerged around 300,000 years ago, likely derived from Homo heidelbergensis.JOURNAL, 10.1126/science.aao6266, 28971970, Southern African ancient genomes estimate modern human divergence to 350,000 to 260,000 years ago, Science, 358, 6363, 652–655, 2017, Schlebusch, Carina M, Malmström, Helena, Günther, Torsten, Sjödin, Per, Coutinho, Alexandra, Edlund, Hanna, Munters, Arielle R, Vicente, Mário, Steyn, Maryna, Soodyall, Himla, Lombard, Marlize, Jakobsson, Mattias, 2017Sci...358..652S, Nonetheless, in September 2019, scientists reported the computerized determination, based on 260 CT scans, of a virtual skull shape of the last common human ancestor to modern humans, and suggested that the human ancestor arose through a merging of populations in East and South Africa, between 260,000 and 350,000 years ago.NEWS, Zimmer, Carl, Carl Zimmer, Scientists Find the Skull of Humanity’s Ancestor — on a Computer - By comparing fossils and CT scans, researchers say they have reconstructed the skull of the last common forebear of modern humans.,weblink 10 September 2019, The New York Times, 10 September 2019, +JOURNAL, Mounier, Aurélien, Lahr, Marta, Deciphering African late middle Pleistocene hominin diversity and the origin of our species,weblink Nature Communications, 10, 1, 3406, 10.1038/s41467-019-11213-w, 10 September 2019, Between 400,000 years ago and the second interglacial period in the Middle Pleistocene, around 250,000 years ago, the trend in intra-cranial volume expansion and the elaboration of stone tool technologies developed, providing evidence for a transition from H. erectus to H. sapiens. The direct evidence suggests there was a migration of H. erectus out of Africa, then a further speciation of H. sapiens from H. erectus in Africa. A subsequent migration (both within and out of Africa) eventually replaced the earlier dispersed H. erectus. This migration and origin theory is usually referred to as the "recent single-origin hypothesis" or "out of Africa" theory. H. sapiens interbred with archaic humans both in Africa and in Eurasia, in Eurasia notably with Neanderthals and Denisovans.The Toba catastrophe theory, which postulates a population bottleneck for H. sapiens about 70,000 years ago,JOURNAL, Ambrose, Stanley H., June 1998, Late Pleistocene human population bottlenecks, volcanic winter, and differentiation of modern humans, Journal of Human Evolution, 34, 6, 623–651, 10.1006/jhev.1998.0219, 0047-2484, 9650103, was controversial from its first proposal in the 1990s and by the 2010s had very little support.JOURNAL, 10.1073/pnas.0909000107, CITEREFHuffothers2010, Chad. D, Huff, Jinchuan, Xing, Alan R., Rogers, David, Witherspoon, Lynn B., Jorde, Mobile Elements Reveal Small Population Size in the Ancient Ancestors of Homo Sapiens, Proceedings of the National Academy of Sciences, 107, 5, 2147–2152, 19 January 2010, 2836654, 20133859,weblink 2010PNAS..107.2147H, Distinctive human genetic variability has arisen as the result of the founder effect, by archaic admixture and by recent evolutionary pressures.

Use of tools

File:Pierre taillée Melka Kunture Éthiopie fond.jpg|thumb|"A sharp rock", an OldowanOldowan(File:Small bonfire.JPG|thumb|The harnessing of fire was a pivotal milestone in human history.)File:Acheuleanhandaxes.jpg|thumb|upright|Acheulean hand-axes from Kent. Homo erectus flintflintFile:Venus of Willendorf frontview retouched 2.jpg|thumb|upright|Venus of Willendorf, an example of PaleolithicPaleolithic{{See also|Hunting hypothesis}}The use of tools has been interpreted as a sign of intelligence, and it has been theorized that tool use may have stimulated certain aspects of human evolution, especially the continued expansion of the human brain.JOURNAL, Ko, Kwang Hyun, Origins of human intelligence: The chain of tool-making and brain evolution, Anthropological Notebooks, 2016, 22, 1, 5–22,weblink Paleontology has yet to explain the expansion of this organ over millions of years despite being extremely demanding in terms of energy consumption. The brain of a modern human consumes about 13 watts (260 kilocalories per day), a fifth of the body's resting power consumption.JOURNAL, Jabr, Ferris, July 18, 2012, Does Thinking Really Hard Burn More Calories?,weblink Scientific American, 0036-8733, 2015-05-03, Increased tool use would allow hunting for energy-rich meat products, and would enable processing more energy-rich plant products. Researchers have suggested that early hominins were thus under evolutionary pressure to increase their capacity to create and use tools.JOURNAL, Gibbons, Ann, May 29, 1998, Solving the Brain's Energy Crisis, Science, 280, 5368, 1345–1347, 10.1126/science.280.5368.1345, 0036-8075, 9634409, Precisely when early humans started to use tools is difficult to determine, because the more primitive these tools are (for example, sharp-edged stones) the more difficult it is to decide whether they are natural objects or human artifacts. There is some evidence that the australopithecines (4 Ma) may have used broken bones as tools, but this is debated.{{harvnb|Robinson|2008|p=398}}Many species make and use tools, but it is the human genus that dominates the areas of making and using more complex tools. The oldest known tools are flakes from West Turkana, Kenya, which date to 3.3 million years ago.JOURNAL, Harmand, Sonia, Lewis, Jason E., Feibel, Craig S., Lepre, Christopher J., Prat, Sandrine, Lenoble, Arnaud, Boës, Xavier, Quinn, Rhonda L., Brenet, Michel, 2015-05-20, 3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya, Nature, En, 521, 7552, 310–315, 10.1038/nature14464, 25993961, 0028-0836, The next oldest stone tools are from Gona, Ethiopia, and are considered the beginning of the Oldowan technology. These tools date to about 2.6 million years ago.JOURNAL, 2003-08-01, 2.6-Million-year-old stone tools and associated bones from OGS-6 and OGS-7, Gona, Afar, Ethiopia, Journal of Human Evolution, en, 45, 2, 169–177, 10.1016/S0047-2484(03)00093-9, 0047-2484, Semaw, Sileshi, Rogers, Michael J., Quade, Jay, Renne, Paul R., Butler, Robert F., Dominguez-Rodrigo, Manuel, Stout, Dietrich, Hart, William S., Pickering, Travis, Simpson, Scott W., A Homo fossil was found near some Oldowan tools, and its age was noted at 2.3 million years old, suggesting that maybe the Homo species did indeed create and use these tools. It is a possibility but does not yet represent solid evidence.{{harvnb|Freeman|Herron|2007|pp=786–788}} The third metacarpal styloid process enables the hand bone to lock into the wrist bones, allowing for greater amounts of pressure to be applied to the wrist and hand from a grasping thumb and fingers. It allows humans the dexterity and strength to make and use complex tools. This unique anatomical feature separates humans from apes and other nonhuman primates, and is not seen in human fossils older than 1.8 million years.JOURNAL, Ward, Carol V., Tocheri, Matthew W., Plavcan, J. Michael, Brown, Francis H., Manthi, Fredrick Kyalo, January 7, 2014, Early Pleistocene third metacarpal from Kenya and the evolution of modern human-like hand morphology, Proc. Natl. Acad. Sci. U.S.A., 111, 1, 121–124, 10.1073/pnas.1316014110, 0027-8424, 3890866, 24344276, 3, 2014PNAS..111..121W, Bernard Wood noted that Paranthropus co-existed with the early Homo species in the area of the "Oldowan Industrial Complex" over roughly the same span of time. Although there is no direct evidence which identifies Paranthropus as the tool makers, their anatomy lends to indirect evidence of their capabilities in this area. Most paleoanthropologists agree that the early Homo species were indeed responsible for most of the Oldowan tools found. They argue that when most of the Oldowan tools were found in association with human fossils, Homo was always present, but Paranthropus was not.In 1994, Randall Susman used the anatomy of opposable thumbs as the basis for his argument that both the Homo and Paranthropus species were toolmakers. He compared bones and muscles of human and chimpanzee thumbs, finding that humans have 3 muscles which are lacking in chimpanzees. Humans also have thicker metacarpals with broader heads, allowing more precise grasping than the chimpanzee hand can perform. Susman posited that modern anatomy of the human opposable thumb is an evolutionary response to the requirements associated with making and handling tools and that both species were indeed toolmakers.

Stone tools

Stone tools are first attested around 2.6 Million years ago, when hominins in Eastern Africa used so-called core tools, choppers made out of round cores that had been split by simple strikes.JOURNAL, Plummer, Thomas, 2004, Flaked stones and old bones: Biological and cultural evolution at the dawn of technology, American Journal of Physical Anthropology, Supplement 39 (Yearbook of Physical Anthropology), 118–164, 10.1002/ajpa.20157, 0002-9483, 15605391, This marks the beginning of the Paleolithic, or Old Stone Age; its end is taken to be the end of the last Ice Age, around 10,000 years ago. The Paleolithic is subdivided into the Lower Paleolithic (Early Stone Age), ending around 350,000–300,000 years ago, the Middle Paleolithic (Middle Stone Age), until 50,000–30,000 years ago, and the Upper Paleolithic, (Late Stone Age), 50,000–10,000 years ago.Archaeologists working in the Great Rift Valley in Kenya have discovered the oldest known stone tools in the world. Dated to around 3.3 million years ago, the implements are some 700,000 years older than stone tools from Ethiopia that previously held this distinction.JOURNAL, Wong, Kate, April 15, 2015, Archaeologists Take Wrong Turn, Find World's Oldest Stone Tools,weblink Scientific American, Blog, 0036-8733, 2015-05-03, JOURNAL, Balter, Michael, April 14, 2015, World's oldest stone tools discovered in Kenya,weblink Science, News, 10.1126/science.aab2487, 0036-8075, 2015-05-03, NEWS, Drake, Nadia, April 16, 2015, Oldest Stone Tools Discovered in Kenya,weblink National Geographic News, Washington, DC, National Geographic Society, 2015-05-03, The period from 700,000–300,000 years ago is also known as the Acheulean, when H. ergaster (or erectus) made large stone hand axes out of flint and quartzite, at first quite rough (Early Acheulian), later "retouched" by additional, more-subtle strikes at the sides of the flakes. After 350,000 BP the more refined so-called Levallois technique was developed, a series of consecutive strikes, by which scrapers, slicers ("racloirs"), needles, and flattened needles were made. Finally, after about 50,000 BP, ever more refined and specialized flint tools were made by the Neanderthals and the immigrant Cro-Magnons (knives, blades, skimmers). In this period they also started to make tools out of bone.

Transition to behavioral modernity

{{See|Behavioral modernity}}Until about 50,000–40,000 years ago, the use of stone tools seems to have progressed stepwise. Each phase (H. habilis, H. ergaster, H. neanderthalensis) started at a higher level than the previous one, but after each phase started, further development was slow. Currently paleoanthropologists are debating whether these Homo species possessed some or many of the cultural and behavioral traits associated with modern humans such as language, complex symbolic thinking, technological creativity etc. It seems that they were culturally conservative maintaining simple technologies and foraging patterns over very long periods.Around 50,000 BP, modern human culture started to evolve more rapidly. The transition to behavioral modernity has been characterized by most as a Eurasian "Great Leap Forward",{{harvnb|Diamond|1999|p=39}} or as the "Upper Palaeolithic Revolution",JOURNAL, Bar-Yosef, Ofer, Ofer Bar-Yosef, October 2002, The Upper Paleolithic Revolution, Annual Review of Anthropology, 31, 363–393, 10.1146/annurev.anthro.31.040402.085416, 0084-6570, due to the sudden appearance of distinctive signs of modern behavior and big game hunting in the archaeological record. Some other scholars consider the transition to have been more gradual, noting that some features had already appeared among archaic African Homo sapiens since 200,000 years ago.JOURNAL, Nowell, April, October 2010, Defining Behavioral Modernity in the Context of Neandertal and Anatomically Modern Human Populations, Annual Review of Anthropology, 39, 437–452, 10.1146/annurev.anthro.012809.105113, 0084-6570, JOURNAL, d'Errico, Francesco, Stringer, Chris B., April 12, 2011, Evolution, revolution or saltation scenario for the emergence of modern cultures?, Philosophical Transactions of the Royal Society B, 366, 1567, 1060–1069, 10.1098/rstb.2010.0340, 0962-8436, 3049097, 21357228, Recent evidence suggests that the Australian Aboriginal population separated from the African population 75,000 years ago, and that they made a sea journey of up to 160 km 60,000 years ago, which may diminish the evidence of the Upper Paleolithic Revolution.JOURNAL, 10.1126/science.1211177, 21940856, 3991479, An Aboriginal Australian Genome Reveals Separate Human Dispersals into Asia, Science, 334, 6052, 94–98, 2011, Rasmussen, M, Guo, X, Wang, Y, Lohmueller, K.E, Rasmussen, S, Albrechtsen, A, Skotte, L, Lindgreen, S, Metspalu, M, Jombart, T, Kivisild, T, Zhai, W, Eriksson, A, Manica, A, Orlando, L, de la Vega, F.M, Tridico, S, Metspalu, E, Nielsen, K, Avila-Arcos, M.C., Moreno-Mayar, J.V., Muller, C, Dortch, J, Gilbert, M.T.P., Lund, O, Wesolowska, A, Karmin, M, Weinert, L.A., Wang, B, Li, J, 29, 2011Sci...334...94R, Modern humans started burying their dead, using animal hides to make clothing, hunting with more sophisticated techniques (such as using trapping pits or driving animals off cliffs), and engaging in cave painting.JOURNAL, Ambrose, Stanley H., March 2, 2001, Paleolithic Technology and Human Evolution, Science, 291, 5509, 1748–1753, 2001Sci...291.1748A, 10.1126/science.1059487, 0036-8075, 11249821, As human culture advanced, different populations of humans introduced novelty to existing technologies: artifacts such as fish hooks, buttons, and bone needles show signs of variation among different populations of humans, something that had not been seen in human cultures prior to 50,000 BP. Typically, H. neanderthalensis populations do not vary in their technologies, although the Chatelperronian assemblages have been found to be Neanderthal innovations produced as a result of exposure to the Homo sapiens Aurignacian technologies.JOURNAL, Mellars, P, 2010, Neanderthal symbolism and ornament manufacture: The bursting of a bubble?, Proc Natl Acad Sci USA, 107, 47, 20147–20148, 10.1073/pnas.1014588107, 21078972, 2996706, 2010PNAS..10720147M, Among concrete examples of modern human behavior, anthropologists include specialization of tools, use of jewellery and images (such as cave drawings), organization of living space, rituals (for example, burials with grave gifts), specialized hunting techniques, exploration of less hospitable geographical areas, and barter trade networks. Debate continues as to whether a "revolution" led to modern humans ("the big bang of human consciousness"), or whether the evolution was more "gradual".

Recent and current human evolution

Evolution has continued in anatomically modern human populations, which are affected by both natural selection and genetic drift. Although selection pressure on some traits, such as resistance to smallpox, has decreased in modern human life, humans are still undergoing natural selection for many other traits. Some of these are due to specific environmental pressures, while others are related to lifestyle changes since the development of agriculture (10,000 years ago), urban civilization (5,000), and industrialization (250 years ago). It has been argued that human evolution has accelerated since the development of agriculture 10,000 years ago and civilization some 5,000 years ago, resulting, it is claimed, in substantial genetic differences between different current human populations.{{harvnb|Cochran|Harpending|2009}}Particularly conspicuous is variation in superficial characteristics, such as Afro-textured hair, or the recent evolution of light skin and blond hair in some populations, which are attributed to differences in climate. Particularly strong selective pressures have resulted in high-altitude adaptation in humans, with different ones in different isolated populations. Studies of the genetic basis show that some developed very recently, with Tibetans evolving over 3,000 years to have high proportions of an allele of EPAS1 that is adaptive to high altitudes.Other evolution is related to endemic diseases: the presence of malaria selected for sickle cell trait (the heterozygote form of sickle cell gene), while the absence of malaria and the health effects of sickle-cell anemia select against this trait. For example, the population at risk of the severe debilitating disease kuru has significant over-representation of an immune variant of the prion protein gene G127V versus non-immune alleles. The frequency of this genetic variant is due to the survival of immune persons.NEWS, Medical Research Council (UK), Medical Research Council (United Kingdom), November 21, 2009, Brain Disease 'Resistance Gene' evolves in Papua New Guinea community; could offer insights Into CJD,weblink ScienceDaily, Rockville, MD, ScienceDaily, LLC, 2009-11-22, JOURNAL, 10.1056/NEJMoa0809716, 19923577, 2009, Mead, S., Whitfield, J., Poulter, M., Shah, P., Uphill, J., Campbell, T., Al-Dujaily, H., Hummerich, H., Beck, J., Mein, C.A., Verzilli, C., Whittaker, J., Alpers, M.P., Collinge, J., A Novel Protective Prion Protein Variant that Colocalizes with Kuru Exposure, 361, 21, 2056–2065, The New England Journal of Medicine,weblink Recent human evolution related to agriculture includes genetic resistance to infectious disease that has appeared in human populations by crossing the species barrier from domesticated animals,{{harvnb|Diamond|1999}} as well as changes in metabolism due to changes in diet, such as lactase persistence.In contemporary times, since industrialization, some trends have been observed: for instance, menopause is evolving to occur later. Other reported trends appear to include lengthening of the human reproductive period and reduction in cholesterol levels, blood glucose and blood pressure in some populations.JOURNAL, S.G., Byars, Govindaraju, D., D.R., Ewbank, S.C., Stearns, Natural selection in a contemporary human population, Proceedings of the National Academy of Sciences, 2009, 19858476, 2868295, 10.1073/pnas.0906199106, 107, suppl_1, 1787–1792, 2010PNAS..107.1787B,

Species list

This list is in chronological order across the table by genus. Some species/subspecies names are well-established, and some are less established – especially in genus Homo. Please see articles for more information.{| class="wikitable" style="text-align: left; width: 600px; height: 800px; margin-left: auto; margin-right: auto; border: none;"! Sahelanthropus !! Homo (human)
S. tchadensis >Homo gautengensis>H. gautengensis
! Orrorin
Homo habilis>H. habilis
O. tugenensis >Homo rudolfensis>H. rudolfensis
! Ardipithecus
Homo floresiensis>H. floresiensis
Ardipithecus#Ardipithecus kadabba>A. kadabba H. ergaster
Ardipithecus#Ardipithecus ramidus>A. ramidus H. erectus
! Australopithecus| • H. e. georgicus
Australopithecus anamensis>A. anamensis H. cepranensis
Australopithecus afarensis>A. afarensis H. antecessor
Australopithecus bahrelghazali>A. bahrelghazali{{padHomo heidelbergensis>H. heidelbergensis
Australopithecus africanus>A. africanus H. rhodesiensis
Australopithecus garhi>A. garhi H. naledi
Australopithecus sediba>A. sediba H. helmei
! Kenyanthropus
Neanderthal>H. neanderthalensis
K. platyops >| H. sapiens
! Paranthropus
Homo sapiens idaltu>H. s. idaltu
Paranthropus aethiopicus>P. aethiopicus • H. s. sapiens'' (early)
Paranthropus boisei>P. boisei • H. s. sapiens (modern)
Paranthropus robustus>P. robustus

See also

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  • BOOK, Aiello, Leslie C. Aiello, Leslie, Dean, Christopher, 1990, An Introduction to Human Evolutionary Anatomy, London; San Diego, Academic Press, Elsevier Academic Press, 978-0-12-045591-1, 95185095, 33408268, harv,
  • BOOK, American Heritage Dictionaries (editors), The American Heritage Dictionary of the English Language, 2006, More Word Histories and Mysteries: From Aardvark to Zombie, Boston, MA, Houghton Mifflin Harcourt, Houghton Mifflin, 978-0-618-71681-4, 2006020835, 70199867, harv,
  • BOOK, Bogin, Barry, Barry Bogin, 1997, The Evolution of Human Nutrition, Romanucci-Ross, Lola, Moerman, Daniel E., Daniel Moerman, Tancredi, Laurence R., The Anthropology of Medicine: From Culture to Method, 3rd, Westport, CT, Greenwood Publishing Group, Bergin & Garvey, 978-0-89789-516-3, 96053993, 36165190, harv,
  • BOOK, Bown, Thomas M., Rose, Kenneth D., 1987, Patterns of Dental Evolution in Early Eocene Anaptomorphine Primates (Omomyidae) From the Bighorn Basin, Wyoming,weblink PDF, Memoir (Paleontological Society), 23, Tulsa, OK, Paleontological Society, 16997265, harv,
  • BOOK, Boyd, Robert, Robert Boyd (anthropologist), Silk, Joan B., 2003, How Humans Evolved, 3rd, New York, W.W. Norton & Company, 978-0-393-97854-4, 2002075336, 49959461, harv,
  • BOOK, Brues, Alice M., Alice Mossie Brues, Snow, Clyde C., Clyde Snow, 1965, Physical Anthropology, Siegel, Bernard J., Biennial Review of Anthropology 1965, Stanford, CA, Stanford University Press, Annual Review of Anthropology, Biennial Review of Anthropology, 4, 978-0-8047-1746-5, 0067-8503, 59012726, 01532912, harv,
  • BOOK, Bryson, Bill, Bill Bryson, 2004, Originally published 2003, The Mysterious Biped, A Short History of Nearly Everything, Toronto, Random House of Canada, Anchor Canada, 978-0-385-66004-4, 2003046006, 55016591, harv, A Short History of Nearly Everything,
  • BOOK, Cameron, David W., 2004, Hominid Adaptations and Extinctions, Sydney, NSW, UNSW Press, 978-0-86840-716-6, 2004353026, 57077633, harv,
  • BOOK, Cochran, Gregory, Gregory Cochran, Harpending, Henry, Henry Harpending, 2009, The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, New York, Basic Books, 978-0-465-00221-4, 2008036672, 191926088, harv, The 10,000 Year Explosion,
  • BOOK, Curry, James R., 2008, Children of God: Children of Earth, Bloomington, IN, AuthorHouse, 978-1-4389-1846-4, 421466369, harv,
  • BOOK, Darwin, Charles, Charles Darwin, 1981, Originally published 1871; London: John Murray (publisher), John Murray, The Descent of Man, and Selection in Relation to Sex, Introduction by John Tyler Bonner and Robert May, Baron May of Oxford, Robert M. May, Reprint, Princeton, NJ, Princeton University Press, 978-0-691-02369-4, 80008679, 7197127, harv, The Descent of Man, and Selection in Relation to Sex,
  • BOOK, Dawkins, Richard, Richard Dawkins, 2004, The Ancestor's Tale: A Pilgrimage to the Dawn of Evolution, Boston, MA, Houghton Mifflin, 978-0-618-00583-3, 2004059864, 56617123, harv, The Ancestor's Tale,
  • BOOK, DeSalle, Rob, Tattersall, Ian, Ian Tattersall, 2008, Human Origins: What Bones and Genomes Tell Us About Ourselves, Texas A&M University Anthropology Series, 13, 1st, College Station, TX, Texas A&M University Press, 978-1-58544-567-7, 144520427, harv,
  • BOOK, Diamond, Jared, Jared Diamond, Guns, Germs, and Steel: The Fates of Human Societies, New York, W.W. Norton & Company, 1999, 978-0-393-31755-8, 2005284124, 35792200, harv, Guns, Germs, and Steel,
  • BOOK, Freeman, Scott, Herron, Jon C., 2007, Evolutionary Analysis, 4th, Upper Saddle River, NJ, Prentice Hall, Pearson Prentice Hall, 978-0-13-227584-2, 2006034384, 73502978, harv,
  • BOOK, Galinon-Melenec, Béatrice, From "Traces" and "Human Trace" to "Human–Trace Paradigm", Parrend, Pierre, Bourgine, Paul, Collet, Pierre, 2015, First Complex systems Digital Campus World E-Conference, Springer Nature, Springer, Tempe, Arizona,
  • BOOK, Johanson, Donald, Donald C. Johanson, Edey, Maitland, 1981, Lucy, the Beginnings of Humankind, St Albans, Granada, 978-0-586-08437-3, harv,
  • BOOK, Montgomery, William M., Germany, Glick, Thomas F., 1988, Originally published 1974, The Comparative Reception of Darwinism, Chicago, Illinois, University of Chicago Press, 978-0-226-29977-8, 87035814, 17328115, harv, "The Conference on the Comparative Reception of Darwinism was held in Austin, Texas, on April 22 and 23, 1972, under the joint sponsorship of the American Council of Learned Societies and the University of Texas at Austin"
  • BOOK, Kondo, Shiro, 1985, Primate Morphophysiology, Locomotor Analyses, and Human Bipedalism, American Journal of Physical Anthropology, 70, 2, 278–279, Tokyo, University of Tokyo Press, 10.1002/ajpa.1330700214, 978-4-13-066093-8, 85173489, 12352830, harv,
  • BOOK, Leakey, Richard E., Richard Leakey, The Origin of Humankind, Science Masters Series, New York, Basic Books, 1994, 978-0-465-03135-1, 94003617, 30739453, harv,weblink
  • BOOK, M'charek, Amade, 2005, The Human Genome Diversity Project: An Ethnography of Scientific Practice, Cambridge Studies in Society and the Life Sciences, Cambridge; New York, Cambridge University Press, 978-0-521-83222-9, 2004052648, 55600894, harv,
  • ENCYCLOPEDIA, Martin, Robert D., Robert D. Martin, Smelser, Neil J., Neil Smelser, Baltes, Paul B., Paul Baltes, International Encyclopedia of the Social & Behavioral Sciences, 2001, 1st, Elsevier, Amsterdam; New York, 978-0-08-043076-8, 2001044791, 47869490, 10.1016/B0-08-043076-7/03083-7, harv, Primates, Evolution of, International Encyclopedia of the Social & Behavioral Sciences, 12032–12038,
  • BOOK, Maxwell, Mary, 1984, Human Evolution: A Philosophical Anthropology, New York, Columbia University Press, 978-0-231-05946-6, 83024005, 10163036, harv,
  • BOOK, McHenry, Henry M., Henry McHenry, 2009, Human Evolution, Ruse, Michael, Michael Ruse, Travis, Joseph, Joseph Travis, Evolution: The First Four Billion Years, Foreword by Edward O. Wilson, Cambridge, Massachusetts, Harvard University Press, Belknap Press of Harvard University Press, 978-0-674-03175-3, 2008030270, 225874308, harv,weblinkweblink
  • BOOK, Ramachandran, Sohini, Hua Tang, Gutenkunst, Ryan N., Bustamante, Carlos D., Carlos D. Bustamante, 2010, Genetics and Genomics of Human Population Structure, Speicher, Michael R., Antonarakis, Stylianos E., Stylianos Antonarakis, Motulsky, Arno G., Vogel and Motulsky's Human Genetics: Problems and Approaches, 4th completely rev., Heidelberg; London; New York, Springer Science+Business Media, Springer, 10.1007/978-3-540-37654-5, 978-3-540-37653-8, 2009931325, 549541244, harv,
  • BOOK, Robinson, J.T., John T. Robinson, 2008, Originally published 1963; Chicago, Illinois: Aldine Transaction, Adaptive Radiation in the Australopithecines and the Origin of Man, Howell, F. Clark, Francis Clark Howell, Bourlière, François, African Ecology and Human Evolution, New Brunswick, NJ, Transaction Publishers, 978-0-202-36136-9, 2007024716, 144770218, harv,
  • BOOK, Srivastava, R.P., 2009, Morphology of the Primates and Human Evolution, New Delhi, PHI Learning Private Limited, 978-81-203-3656-8, 423293609, harv,
  • BOOK, Stanford, Craig, Craig Stanford, Allen, John S., Antón, Susan C., 2009, Biological Anthropology: The Natural History of Humankind, 2nd, Upper Saddle River, NJ, Pearson Prentice Hall, 978-0-13-601160-6, 2007052429, 187548835, harv,weblink
  • BOOK, Strickberger, Monroe W., 2000, Evolution, 3rd, Sudbury, MA, Jones and Bartlett Publishers, 978-0-7637-1066-8, 99032072, 41431683, harv,
  • BOOK, Stringer, Chris B., Chris Stringer, 1994, First published 1992, Evolution of Early Humans, Jones, Steve, Steve Jones (biologist), Martin, Robert D., Pilbeam, David, David Pilbeam, The Cambridge Encyclopedia of Human Evolution, Foreword by Richard Dawkins, 1st paperback, Cambridge, UK, Cambridge University Press, 978-0-521-32370-3, 92018037, 444512451, harv,weblinkweblink
  • BOOK, Swisher, Carl C., III, Curtis, Garniss H., Garniss Curtis, Lewin, Roger, Roger Lewin, 2001, Originally published 2000, Java Man: How Two Geologists Changed Our Understanding of Human Evolution, Chicago, University of Chicago Press, 978-0-226-78734-3, 2001037337, 48066180, harv,
  • JOURNAL, Tishkoff, S.A., Sarah Tishkoff, Reed, F.A., et al., The Genetic Structure and History of Africans and African Americans, 22 May 2009, Science (journal), Science, 324, 5930, 1035–1044, 10.1126/science.1172257, 2947357, 19407144, 2009Sci...324.1035T, 2009,
  • BOOK, Trent, Ronald J., 2005, Molecular Medicine: An Introductory Text, 3rd, Burlington, MA, Elsevier Academic Press, 978-0-12-699057-7, 2004028087, 162577235, harv,
  • BOOK, Trevathan, Wenda R., 2011, Originally published 1987; New York: Aldine De Gruyter, Human Birth: An Evolutionary Perspective, New Brunswick, NJ, Transaction Publishers, 978-1-4128-1502-4, 2010038249, 669122326, harv,
  • BOOK, Ungar, Peter S., Peter Ungar, Teaford, Mark F., 2002, Human Diet: Its Origin and Evolution, Westport, CT, Bergin & Garvey, 978-0-89789-736-5, 2001043790, 537239907, harv,
  • BOOK, Walker, Alan, Alan Walker (anthropologist), 2007, Early Hominin Diets: Overview and Historical Perspectives, Ungar, Peter, Evolution of the Human Diet: The Known, the Unknown, and the Unknowable, Human Evolution Series, Oxford; New York, Oxford University Press, 978-0-19-518346-7, 2005036120, 132816551, harv,
  • BOOK, Wallace, David Rains, David Rains Wallace, 2004, Beasts of Eden: Walking Whales, Dawn Horses, and Other Enigmas of Mammal Evolution, Berkeley, University of California Press, 978-0-520-24684-3, 2003022857, 53254011, harv,
  • BOOK, Webster, Donovan, Donovan Webster, 2010, Meeting the Family: One Man's Journey Through His Human Ancestry, Foreword by Spencer Wells, Washington, DC, National Geographic Society, 978-1-4262-0573-6, 2009050471, 429022321, harv,
  • BOOK, Wood, Bernard A., Where Does the Genus Homo Begin, and How Would We Know?, Grine, Frederick E., Frederick E. Grine, Fleagle, John G., John G. Fleagle, Leakey, Richard E., The First Humans: Origin and Early Evolution of the Genus Homo, 17–28, 2009, Vertebrate Paleobiology and Paleoanthropology, Dordrecht, the Netherlands, Springer Science+Business Media, Springer Netherlands, 10.1007/978-1-4020-9980-9_3, 978-1-4020-9979-3, 1877-9077, 2009927083, 310400980, harv, "Contributions from the Third Stony Brook Human Evolution Symposium and Workshop October 3–7, 2006."

Further reading

  • BOOK, Alexander, Richard D., Richard D. Alexander, 1990, How Did Humans Evolve? Reflections on the Uniquely Unique Species,weblink Special Publication, 1, Ann Arbor, MI, List of museums and collections at the University of MichiganMuseum of Zoology, Museum of Zoology, University of Michigan, 1–38, 90623893, 22860997, harv,
  • BOOK, Barton, Nicholas H., Nick Barton, Briggs, Derek E.G., Derek Briggs, Eisen, Jonathan A., Jonathan Eisen, Goldstein, David B., Patel, Nipan H., 2007, Evolution, Cold Spring Harbor, NY, Cold Spring Harbor Laboratory Press, 978-0-87969-684-9, 2007010767, 86090399, 3,
  • JOURNAL, Enard, Wolfgang, Przeworski, Molly, Fisher, Simon E., Simon Fisher, Lai, Cecilia S. L., Wiebe, Victor, Kitano, Takashi, Monaco, Anthony P., Pääbo, Svante, August 22, 2002, Molecular evolution of FOXP2, a gene involved in speech and language, Nature, 418, 6900, 869–872, 10.1038/nature01025, 0028-0836, 12192408, 3, 2002Natur.418..869E,
  • JOURNAL, Flinn, Mark V., Geary, David C., David C. Geary, Ward, Carol V., January 2005, Ecological dominance, social competition, and coalitionary arms races: Why humans evolved extraordinary intelligence,weblink Evolution and Human Behavior, 26, 1, 10–46, 10.1016/j.evolhumbehav.2004.08.005, 1090-5138, 2015-05-05,
  • BOOK, Gibbons, Ann, 2006, The First Human: The Race to Discover our Earliest Ancestors, 1st, New York, Doubleday, 978-0-385-51226-8, 2005053780, 61652817, harv,weblink
  • BOOK, Hartwig, Walter C., Walter Hartwig, 2002, The Primate Fossil Record, Cambridge Studies in Biological and Evolutionary Anthropology, 33, Cambridge; New York, Cambridge University Press, 978-0-521-66315-1, 2001037847, 47254191, harv,
  • JOURNAL, Heizmann, Elmar P.J., Begun, David R., November 2001, The oldest Eurasian hominoid, Journal of Human Evolution, 41, 5, 10.1006/jhev.2001.0495, 463–481, 0047-2484, 11681862,
  • JOURNAL, Hill, Andrew, Ward, Steven, 1988, Origin of the hominidae: The record of African large hominoid evolution between 14 my and 4 my, American Journal of Physical Anthropology, 31, 59, 49–83, 10.1002/ajpa.1330310505, 0002-9483,
  • JOURNAL, Hoagland, Hudson, Science and the New Humanism, Science (journal), Science, 1964, 143, 3602, 111–114, 10.1126/science.143.3602.111, 17781189, 1964Sci...143..111H,
  • JOURNAL, Ijdo, Jacob W., Baldini, Antonio, Ward, David C., Reeders, Stephen T., Wells, Richard A., October 15, 1991, Origin of human chromosome 2: An ancestral telomere-telomere fusion,weblink Proc. Natl. Acad. Sci. U.S.A., 88, 20, 9051–9055, 1991PNAS...88.9051I, 10.1073/pnas.88.20.9051, 0027-8424, 52649, 1924367, 3, 2015-05-05, – two ancestral ape chromosomes fused to give rise to human chromosome 2
  • BOOK, Johanson, Donald, Donald Johanson, Wong, Kate, 2010, Lucy's Legacy: The Quest for Human Origins, New York, Three Rivers Press, 978-0-307-39640-2, 2010483830, 419801728, harv,
  • BOOK, Jones, Steve, Martin, Robert D., Pilbeam, David, 1994, First published 1992, The Cambridge Encyclopedia of Human Evolution, Foreword by Richard Dawkins, 1st paperback, Cambridge, UK, Cambridge University Press, 978-0-521-32370-3, 92018037, 444512451, harv,weblink (Note: this book contains very useful, information dense chapters on primate evolution in general, and human evolution in particular, including fossil history).
  • BOOK, Leakey, Richard E., Lewin, Roger, 1992, Origins Reconsidered: In Search of What Makes us Human, New York, Doubleday, 978-0-385-41264-3, 92006661, 25373161, harv,
  • BOOK, Lewin, Roger, 1997, Bones of Contention: Controversies in the Search for Human Origins, 2nd, Chicago, Illinois, University of Chicago Press, 978-0-226-47651-3, 97000972, 36181117, harv,
  • BOOK, Morwood, Mike, van Oosterzee, Penny, 2007, A New Human: The Startling Discovery and Strange Story of the 'Hobbits' of Flores, Indonesia, 1st Smithsonian Books, New York, Smithsonian Books/HarperCollins, 978-0-06-089908-0, 2006052267, 76481584, harv,weblink
  • BOOK, Oppenheimer, Stephen, Stephen Oppenheimer, 2003, Out of Eden: The Peopling of the World, london, Constable & Robinson, 978-1-84119-697-8, 2005482222, 52195607, harv,
  • JOURNAL, Ovchinnikov, Igor V., Götherström, Anders, Romanova, Galina P., Kharitonov, Vitaliy M., Lidén, Kerstin, Goodwin, William, 3, March 30, 2000, Molecular analysis of Neanderthal DNA from the Northern Caucasus, Nature, 404, 6777, 490–493, 10.1038/35006625, 0028-0836, 10761915,
  • BOOK, Roberts, Alice M., Alice Roberts, 2009, The Incredible Human Journey: The Story of How We Colonised the Planet, London, Bloomsbury Publishing, 978-0-7475-9839-8, 310156315, harv,
  • BOOK, Shreeve, James, 1995, The Neandertal Enigma: Solving the Mystery of Modern Human Origins, New York, William Morrow and Company, Morrow, 978-0-688-09407-2, 95006337, 32088673, harv,weblink
  • BOOK, Stringer, Chris B., 2011, The Origin of Our Species, London, Penguin Books, Allen Lane, 978-1-84614-140-9, 2011489742, 689522193, harv,
  • BOOK, Stringer, Chris B., Andrews, Peter, 2005, The Complete World of Human Evolution, London; New York, Thames & Hudson, 978-0-500-05132-0, 2004110563, 224377190, harv,
  • BOOK, Stringer, Christopher, McKie, Robin, 1997, African Exodus: The Origins of Modern Humanity, 1st American, New York, Henry Holt and Company, 978-0-8050-2759-4, 96037718, 36001167, harv,weblink
  • BOOK, Tattersall, Ian, 2008, The Fossil Trail: How We Know What We Think We Know About Human Evolution, 2nd, New York, Oxford University, 978-0195367669, 2008013654, 218188644, harv,
  • BOOK, van Oosterzee, Penny, 1999, Dragon Bones: The Story of Peking Man, St Leonards, New South Wales, Allen & Unwin, 978-1-86508-123-6, 00300421, 45853997, harv,
  • BOOK, Wade, Nicholas, Nicholas Wade, 2006, Before the Dawn: Recovering the Lost History of Our Ancestors, New York, Penguin Press, 978-1-59420-079-3, 2005055293, 62282400, harv, Before the Dawn (book),
  • BOOK, Walker, Alan, Shipman, Pat, 1996, The Wisdom of the Bones: In Search of Human Origins, London, Weidenfeld & Nicolson, 978-0-297-81670-6, 35202130, harv,
  • BOOK, Weiss, Mark L., Mann, Alan E., 1985, Human Biology and Behavior: An Anthropological Perspective, 4th, Boston, Little Brown, 978-0-316-92894-6, 85000158, 11726796, harv, (Note: this book contains very accessible descriptions of human and non-human primates, their evolution, and fossil history).
  • BOOK, Wells, Spencer, Spencer Wells, 2003, Originally published 2002; Princeton, NJ: Princeton University Press, The Journey of Man: A Genetic Odyssey, Random House trade paperback, New York, Random House, Random House Trade Paperbacks, 978-0-8129-7146-0, 2003066679, 53287806, harv,

External links

{{Commons category|Human evolution}} {{Human Evolution}}{{Human genetics}}{{Apes}}{{Prehistoric technology}}{{Evolutionary psychology}}

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