SUPPORT THE WORK

GetWiki

experimental evolution

ARTICLE SUBJECTS
aesthetics  →
being  →
complexity  →
database  →
enterprise  →
ethics  →
fiction  →
history  →
internet  →
knowledge  →
language  →
licensing  →
linux  →
logic  →
method  →
news  →
perception  →
philosophy  →
policy  →
purpose  →
religion  →
science  →
sociology  →
software  →
truth  →
unix  →
wiki  →
ARTICLE TYPES
essay  →
feed  →
help  →
system  →
wiki  →
ARTICLE ORIGINS
critical  →
discussion  →
forked  →
imported  →
original  →
experimental evolution
[ temporary import ]
please note:
- the content below is remote from Wikipedia
- it has been imported raw for GetWiki
{{short description|Use of laboratory and field experiments to explore evolutionary dynamics}}{{lead too long|date=July 2018}}{{Evolutionary biology}}Experimental evolution is the use of laboratory experiments or controlled field manipulations to explore evolutionary dynamics.WEB, Experimental Evolution,weblink Nature, Evolution may be observed in the laboratory as individuals/populations adapt to new environmental conditions by natural selection. There are two different ways in which adaptation can arise in experimental evolution. One is via an individual organism gaining a novel beneficial mutation.JOURNAL, Long, A, Liti, G, Luptak, A, Tenaillon, O, 2015, Elucidating the molecular architecture of adaptation via evolve and resequence experiments, Nature Reviews Genetics, 16, 10, 567–582, 10.1038/nrg3937, 1471-0056, 4733663, 26347030, The other is from allele frequency change in standing genetic variation already present in a population of organisms. Other evolutionary forces outside of mutation and natural selection can also play a role or be incorporated into experimental evolution studies, such as genetic drift and gene flow. The organism used is decided by the experimenter, based on whether the hypothesis to be tested involves adaptation through mutation or allele frequency change. A large number of generations are required for adaptive mutation to occur, and experimental evolution via mutation is carried out in viruses or unicellular organisms with rapid generation times, such as bacteria and asexual clonal yeast.JOURNAL, Buckling A, Craig Maclean R, Brockhurst MA, Colegrave N, The Beagle in a bottle, Nature, 457, 7231, 824–9, February 2009, 19212400, 10.1038/nature07892, 2009Natur.457..824B, JOURNAL, Elena SF, Lenski RE, Evolution experiments with microorganisms: the dynamics and genetic bases of adaptation, Nat. Rev. Genet., 4, 6, 457–69, June 2003, 12776215, 10.1038/nrg1088, Polymorphic populations of asexual or sexual yeast, and multicellular eukaryotes like Drosophila, can adapt to new environments through allele frequency change in standing genetic variation.JOURNAL, Kawecki, T.J., Lenski, R.E., Ebert, D., Hollis, B., Olivieri, I., Whitlock, M.C., 2012, Experimental evolution, Trends in Ecology & Evolution, en, 27, 10, 547–560, 10.1016/j.tree.2012.06.001, 22819306, Organisms with longer generations times, although costly, can be used in experimental evolution. Laboratory studies with foxesEarly Canid Domestication: The Fox Farm Experiment, p.2, by Lyudmila N. Trut, Ph.D., Retrieved February 19, 2011 and with rodents (see below) have shown that notable adaptations can occur within as few as 10–20 generations and experiments with wild guppies have observed adaptations within comparable numbers of generations.JOURNAL, Reznick, D. N., F. H. Shaw, F. H. Rodd, R. G. Shaw, 1997, Evaluation of the rate of evolution in natural populations of guppies (Poecilia reticulata), Science, 275, 5308, 1934–1937, 10.1126/science.275.5308.1934, 9072971, More recently, experimentally evolved individuals or populations are often analyzed using whole genome sequencing,JOURNAL, Barrick, Jeffrey E., Lenski, Richard E., Genome dynamics during experimental evolution, Nature Reviews Genetics, 14, 12, 827–839, 10.1038/nrg3564, 4239992, 24166031, 2013, JOURNAL, June 2015, Whole-Genome Resequencing of Experimental Populations Reveals Polygenic Basis of Egg-Size Variation in Drosophila melanogaster, Mol. Biol. Evol., 32, 10, 2616–32, 10.1093/molbev/msv136, 26044351, Jha AR, Miles CM, Lippert NR, Brown CD, White KP, Kreitman M, 4576704, an approach known as Evolve and Resequence (E&R).JOURNAL, Turner TL, Stewart AD, Population-Based Resequencing of Experimentally Evolved Populations Reveals the Genetic Basis of Body Size Variation in Drosophila melanogaster, PLoS Genet., March 2011, 21437274, 10.1371/journal.pgen.1001336, etal, 7, 3, e1001336, 3060078, E&R can identify mutations that lead to adaptation in clonal individuals or identify alleles that changed in frequency in polymorphic populations, by comparing the sequences of individuals/populations before and after adaptation. The sequence data makes it possible to pinpoint the site in a DNA sequence that a mutation/allele frequency change occurred to bring about adaptation. The nature of the adaptation and functional follow up studies can shed insight into what effect the mutation/allele has on phenotype.

History

Domestication and breeding

File:Big and little dog 1.jpg|thumb|right|This Chihuahua mix and Great Dane show the wide range of dog breed sizes created using artificial selectionartificial selectionUnwittingly, humans have carried out evolution experiments for as long as they have been domesticating plants and animals. Selective breeding of plants and animals has led to varieties that differ dramatically from their original wild-type ancestors. Examples are the cabbage varieties, maize, or the large number of different dog breeds. The power of human breeding to create varieties with extreme differences from a single species was already recognized by Charles Darwin. In fact, he started out his book The Origin of Species with a chapter on variation in domestic animals. In this chapter, Darwin discussed in particular the pigeon.{{quotation|Altogether at least a score of pigeons might be chosen, which if shown to an ornithologist, and he were told that they were wild birds, would certainly, I think, be ranked by him as well-defined species. Moreover, I do not believe that any ornithologist would place the English carrier, the short-faced tumbler, the runt, the barb, pouter, and fantail in the same genus; more especially as in each of these breeds several truly-inherited sub-breeds, or species as he might have called them, could be shown him.(...) I am fully convinced that the common opinion of naturalists is correct, namely, that all have descended from the rock-pigeon (Columba livia), including under this term several geographical races or sub-species, which differ from each other in the most trifling respects.|Charles Darwin|The Origin of Species}}

Early

(File:Dallinger Incubator J.R.Microscop.Soc.1887p193.png|thumb|Drawing of the incubator used by Dallinger in his evolution experiments.)One of the first to carry out a controlled evolution experiment was William Dallinger. In the late 19th century, he cultivated small unicellular organisms in a custom-built incubator over a time period of seven years (1880–1886). Dallinger slowly increased the temperature of the incubator from an initial 60 Â°F up to 158 Â°F. The early cultures had shown clear signs of distress at a temperature of 73 Â°F, and were certainly not capable of surviving at 158 Â°F. The organisms Dallinger had in his incubator at the end of the experiment, on the other hand, were perfectly fine at 158 Â°F. However, these organisms would no longer grow at the initial 60 Â°F. Dallinger concluded that he had found evidence for Darwinian adaptation in his incubator, and that the organisms had adapted to live in a high-temperature environment. Dallinger's incubator was accidentally destroyed in 1886, and Dallinger could not continue this line of research.JOURNAL, Hass, J. W., 2000-01-22, The Reverend Dr William Henry Dallinger, F.R.S. (1839–1909),weblink Notes and Records, en, 54, 1, 53–65, 10.1098/rsnr.2000.0096, 0035-9149, 11624308, BOOK,weblink Darwin Under the Microscope: Witnessing Evolution in Microbes, Zimmer, Carl, In the Light of Evolution: Essays from the Laboratory and Field, W. H. Freeman, 2011, 978-0981519494, Losos, Johnathon, 42–43, From the 1880s to 1980, experimental evolution was intermittently practiced by a variety of evolutionary biologists, including the highly influential Theodosius Dobzhansky. Like other experimental research in evolutionary biology during this period, much of this work lacked extensive replication and was carried out only for relatively short periods of evolutionary time.JOURNAL, Dobzhansky, T, Pavlovsky, O, An experimental study of interaction between genetic drift and natural selection, Evolution, 1957, 11, 3, 311–319, 10.2307/2405795, 2405795,

Modern

Experimental evolution has been used in various formats to understand underlying evolutionary processes in a controlled system. Experimental evolution has been performed on multicellularJOURNAL, Marden, JH, Wolf, MR, Weber, KE, Aerial performance of Drosophila melanogaster from populations selected for upwind flight ability., The Journal of Experimental Biology, November 1997, 200, Pt 21, 2747–55, 9418031, and unicellularJOURNAL, Ratcliff, WC, Denison, RF, Borrello, M, Travisano, M, Experimental evolution of multicellularity., Proceedings of the National Academy of Sciences of the United States of America, 31 January 2012, 109, 5, 1595–600, 22307617, 10.1073/pnas.1115323109, 3277146, 2012PNAS..109.1595R, eukaryotes, prokaryotes,JOURNAL, Barrick, JE, Yu, DS, Yoon, SH, Jeong, H, Oh, TK, Schneider, D, Lenski, RE, Kim, JF, Genome evolution and adaptation in a long-term experiment with Escherichia coli., Nature, 29 October 2009, 461, 7268, 1243–7, 19838166, 10.1038/nature08480, 2009Natur.461.1243B, and viruses.JOURNAL, Heineman, RH, Molineux, IJ, Bull, JJ, Evolutionary robustness of an optimal phenotype: re-evolution of lysis in a bacteriophage deleted for its lysin gene., Journal of Molecular Evolution, August 2005, 61, 2, 181–91, 16096681, 10.1007/s00239-004-0304-4, 2005JMolE..61..181H, Similar works have also been performed by directed evolution of individual enzyme,JOURNAL, Bloom, JD, Arnold, FH, In the light of directed evolution: pathways of adaptive protein evolution., Proceedings of the National Academy of Sciences of the United States of America, 16 June 2009, 106 Suppl 1, 9995–10000, 19528653, 10.1073/pnas.0901522106, 2702793, JOURNAL, Moses, AM, Davidson, AR, In vitro evolution goes deep., Proceedings of the National Academy of Sciences of the United States of America, 17 May 2011, 108, 20, 8071–2, 21551096, 10.1073/pnas.1104843108, 3100951, 2011PNAS..108.8071M, ribozymeJOURNAL, Salehi-Ashtiani, K, Szostak, JW, In vitro evolution suggests multiple origins for the hammerhead ribozyme., Nature, 1 November 2001, 414, 6859, 82–4, 11689947, 10.1038/35102081, 2001Natur.414...82S, and replicatorJOURNAL, Sumper, M, Luce, R, Evidence for de novo production of self-replicating and environmentally adapted RNA structures by bacteriophage Qbeta replicase., Proceedings of the National Academy of Sciences of the United States of America, January 1975, 72, 1, 162–6, 1054493, 10.1073/pnas.72.1.162, 432262, JOURNAL, Mills, DR, Peterson, RL, Spiegelman, S, An extracellular Darwinian experiment with a self-duplicating nucleic acid molecule., Proceedings of the National Academy of Sciences of the United States of America, July 1967, 58, 1, 217–24, 5231602, 10.1073/pnas.58.1.217, 335620, 1967PNAS...58..217M, genes.

Aphids

In the 1950s, the Soviet biologist Georgy Shaposhnikov conducted (:ru:Опыты Георгия Шапошникова по искусственной эволюции|experiments) on aphids of the (species:Dysaphis|Dysaphis) genus. By transferring them to plants normally nearly or completely unsuitable for them, he had forced populations of parthenogenetic descendants to adapt to the new food source to the point of reproductive isolation from the regular populations of the same species.weblink" title="https:/-/web.archive.org/web/20130908054552weblink">weblink

Fruit flies

One of the first of a new wave of experiments using this strategy was the laboratory "evolutionary radiation" of Drosophila melanogaster populations that Michael R. Rose started in February, 1980.JOURNAL, Rose, M. R., 1984, Artificial selection on a fitness component in Drosophila melanogaster, 2408701, Evolution, 38, 3, 516–526, 10.2307/2408701, 28555975, This system started with ten populations, five cultured at later ages, and five cultured at early ages. Since then more than 200 different populations have been created in this laboratory radiation, with selection targeting multiple characters. Some of these highly differentiated populations have also been selected "backward" or "in reverse," by returning experimental populations to their ancestral culture regime. Hundreds of people have worked with these populations over the better part of three decades. Much of this work is summarized in the papers collected in the book Methuselah Flies.BOOK, Methuselah Flies, Rose, Michael R, Passananti, Hardip B, Matos, Margarida, World Scientific, 2004, 978-981-238-741-7, Singapore, 10.1142/5457, The early experiments in flies were limited to studying phenotypes but the molecular mechanisms, i.e., changes in DNA that facilitated such changes, could not be identified. This changed with genomics technology.JOURNAL, Burke MK, Dunham JP, Genome-wide analysis of a long-term evolution experiment with Drosophila, Nature, Sep 2015, 20844486, 10.1038/nature09352, etal, 467, 7315, 587–90, Subsequently, Thomas Turner coined the term Evolve and Resequence (E&R) and several studies used E&R approach with mixed success.JOURNAL, Schlötterer C, Tobler R, Kofler R, Nolte V, Sequencing pools of individuals - mining genome-wide polymorphism data without big funding, Nat. Rev. Genet., Nov 2014, 25246196, 10.1038/nrg3803, 15, 11, 749–63, JOURNAL, Schlötterer C, Kofler R, Versace E, Tobler R, Franssen SU, Combining experimental evolution with next-generation sequencing: a powerful tool to study adaptation from standing genetic variation, Heredity, Oct 2014, 25269380, 10.1038/hdy.2014.86, 114, 5, 431–40, 4815507, One of the more interesting experimental evolution studies was conducted by Gabriel Haddad's group at UC San Diego, where Haddad and colleagues evolved flies to adapt to low oxygen environments, also known as hypoxia.JOURNAL, Zhou D, Xue J, Chen J, Morcillo P, Lambert JD, White KP, Haddad GG, Experimental selection for Drosophila survival in extremely low O(2) environment, PLOS ONE, May 2007, 17534440, 10.1371/journal.pone.0000490, 2, 5, e490, 1871610, 2007PLoSO...2..490Z, After 200 generations, they used E&R approach to identify genomic regions that were selected by natural selection in the hypoxia adapted flies.JOURNAL, Zhou D, Udpa N, Gersten M, Visk DW, Bashir A, Xue J, Frazer KA, Posakony JW, Subramaniam S, Bafna V, Haddad GG, Experimental selection of hypoxia-tolerant Drosophila melanogaster, Proc. Natl. Acad. Sci. USA, Feb 2011, 21262834, 10.1073/pnas.1010643108, 108, 6, 2349–54, 3038716, 2011PNAS..108.2349Z, More recent experiments are following up E&R predictions with RNAseqJOURNAL, Remolina SC, Chang PL, Leips J, Nuzhdin SV, Hughes KA, Genomic basis of aging and life-history evolution in Drosophila melanogaster, Evolution, Nov 2012, 23106705, 10.1111/j.1558-5646.2012.01710.x, 66, 11, 3390–403, 4539122, and genetic crosses. Such efforts in combining E&R with experimental validations should be powerful in identifying genes that regulate adaptation in flies.

Bacteria

Bacteria have short generation times, easily sequenced genomes, and well-understood biology. They are therefore commonly used for experimental evolution studies.

Lenski's E. coli experiment

One of the most widely known examples of laboratory bacterial evolution is the long-term E.coli experiment of Richard Lenski. On February 24, 1988, Lenski started growing twelve lineages of E. coli under identical growth conditions.JOURNAL, Lenski, Richard E., Rose, Michael R., Simpson, Suzanne C., Tadler, Scott C., 1991-12-01, Long-Term Experimental Evolution in Escherichia coli. I. Adaptation and Divergence During 2,000 Generations, The American Naturalist, 138, 6, 1315–1341, 10.1086/285289, 0003-0147, JOURNAL, Fox, Jeremy W., Lenski, Richard E., 2015-06-23, From Here to Eternity—The Theory and Practice of a Really Long Experiment, PLOS Biology, 13, 6, e1002185, 10.1371/journal.pbio.1002185, 1545-7885, 4477892, 26102073, When one of the populations evolved the ability to aerobically metabolize citrate from the growth medium and showed greatly increased growth,JOURNAL, Blount, Zachary D., Borland, Christina Z., Lenski, Richard E., 2008-06-10, Historical contingency and the evolution of a key innovation in an experimental population of Escherichia coli, Proceedings of the National Academy of Sciences, en, 105, 23, 7899–7906, 10.1073/pnas.0803151105, 0027-8424, 2430337, 18524956, this provided a dramatic observation of evolution in action. The experiment continues to this day, and is now the longest-running (in terms of generations) controlled evolution experiment ever undertaken.{{Citation needed|date=November 2016}} Since the inception of the experiment, the bacteria have grown for more than 60,000 generations. Lenski and colleagues regularly publish updates on the status of the experiments.E. coli Long-term Experimental Evolution Project Site, Lenski, R. E.

Laboratory mice

(File:Wheel Counter Box 1.jpg|thumb|left|Mouse from the Garland selection experiment with attached running wheel and its rotation counter.)In 1998, Theodore Garland, Jr. and colleagues started a long-term experiment that involves selective breeding of mice for high voluntary activity levels on running wheels.Artificial Selection for Increased Wheel-Running Behavior in House Mice, John G. Swallow, Patrick A. Carter, and Theodore Garland, Jr., Behavior Genetics, Vol. 28, No. 3, 1998 This experiment also continues to this day (> 65 generations). Mice from the four replicate "High Runner" lines evolved to run almost three times as many running-wheel revolutions per day compared with the four unselected control lines of mice, mainly by running faster than the control mice rather than running for more minutes/day.(File:LitterMom1480.jpg|thumb|right|Female mouse with her litter, from the Garland selection experiment.)The HR mice exhibit an elevated maximal aerobic capacity when tested on a motorized treadmill. They also exhibit alterations in motivation and the reward system of the brain. Pharmacological studies point to alterations in dopamine function and the endocannabinoid system.JOURNAL, Keeney BK, Raichlen DA, Meek TH, Wijeratne RS, Middleton KM, Gerdeman GL, Garland T, 2008, Differential response to a selective cannabinoid receptor antagonist (SR141716: rimonabant) in female mice from lines selectively bred for high voluntary wheel-running behavior,weblink Behavioural Pharmacology, 19, 8, 812–820, 10.1097/FBP.0b013e32831c3b6b, 19020416, The High Runner lines have been proposed as a model to study human attention-deficit hyperactivity disorder (ADHD), and administration of Ritalin reduces their wheel running approximately to the levels of control mice. Click here for a mouse wheel running video.

Other examples

Stickleback fish have both marine and freshwater species, the freshwater species evolving since the last ice age. Freshwater species can survive colder temperatures. Scientists tested to see if they could reproduce this evolution of cold-tolerance by keeping marine sticklebacks in cold freshwater. It took the marine sticklebacks only three generations to evolve to match the 2.5 degree Celsius improvement in cold-tolerance found in wild freshwater sticklebacks.JOURNAL, Barrett, R. D. H., Paccard, A., Healy, T. M., Bergek, S., Schulte, P. M., Schluter, D., Rogers, S. M., Rapid evolution of cold tolerance in stickleback, Proceedings of the Royal Society B: Biological Sciences, 2010, 278, 1703, 233–238, 10.1098/rspb.2010.0923, 20685715, 3013383, Microbial cells JOURNAL, Dragosits, Martin, Mattanovich, Diethard, Adaptive laboratory evolution – principles and applications for biotechnology, Microbial Cell Factories, 12, 1, 2013, 64, 1475-2859, 10.1186/1475-2859-12-64, 23815749, 3716822, and recently mammalian cells JOURNAL, Maralingannavar, Vishwanathgouda, Parmar, Dharmeshkumar, Pant, Tejal, Gadgil, Chetan, Panchagnula, Venkateswarlu, Gadgil, Mugdha, CHO cells adapted to inorganic phosphate limitation show higher growth and higher pyruvate carboxylase flux in phosphate replete conditions, Biotechnology Progress, 33, 3, 749–758, 2017, 8756-7938, 10.1002/btpr.2450, 28220676, are evolved under nutrient limiting conditions to study their metabolic response and engineer cells for better characteristics.

For teaching

Because of their rapid generation times microbes offer an opportunity to study microevolution in the classroom. A number of exercises involving bacteria and yeast teach concepts ranging from the evolution of resistanceJOURNAL, Hyman, Paul, Bacteriophage as instructional organisms in introductory biology labs, Bacteriophage, 4, 2, 2014, e27336, 2159-7081, 10.4161/bact.27336, 24478938, 3895413, to the evolution of multicellularity.JOURNAL, A Novel Laboratory Activity for Teaching about the Evolution of Multicellularity, The American Biology Teacher, 76, 2, 2014, 81–87, 0002-7685, 10.1525/abt.2014.76.2.3, With the advent of next-generation sequencing technology it has become possible for students to conduct an evolutionary experiment, sequence the evolved genomes, and to analyze and interpret the results.JOURNAL, Using experimental evolution and next-generation sequencing to teach bench and bioinformatic skills, PeerJ PrePrints, 3, 2015, e1674, 10.7287/peerj.preprints.1356v1,weblink Mikheyev, Alexander S., Arora, Jigyasa,

See also

References

{{reflist|35em}}

Further reading

  • JOURNAL


, Bennett
, A. F.
, Experimental evolution and the Krogh Principle: generating biological novelty for functional and genetic analyses
, Physiological and Biochemical Zoology
, 76
, 1
, 1–11
, 2003
,weblink
, 10.1086/374275
,
, 12695982,
  • Dallinger, W. H. 1887. The president's address. J. Roy. Microscop. Soc., 185-199.
  • JOURNAL, Elena, S. F., Lenski, R. E., 2003, Evolution experiments with microorganisms: the dynamics and genetic bases of adaptation, Nature Reviews Genetics, 4, 6, 457–469, 10.1038/nrg1088, 12776215,
  • Garland, T., Jr. 2003. Selection experiments: an under-utilized tool in biomechanics and organismal biology. Pages 23–56 in V. L. Bels, J.-P. Gasc, A. Casinos, eds. Vertebrate biomechanics and evolution. BIOS Scientific Publishers, Oxford, UK. PDF
  • Garland, T., Jr., and M. R. Rose, eds. 2009. Experimental evolution: concepts, methods, and applications of selection experiments. University of California Press, Berkeley, California. PDF of Table of Contents
  • JOURNAL, Gibbs, A. G., 1999, Laboratory selection for the comparative physiologist, Journal of Experimental Biology, 202, 2709–2718,
  • BOOK, Lenski, R. E., 2004, Phenotypic and genomic evolution during a 20,000-generation experiment with the bacterium Escherichia coli, Plant Breeding Reviews, 24, 225–265, 10.1002/9780470650288.ch8, 9780470650288,
  • JOURNAL, Lenski, R. E., Rose, M. R., Simpson, S. C., Tadler, S. C., 1991, Long-term experimental evolution in Escherichia coli. I. Adaptation and divergence during 2,000 generations, American Naturalist, 138, 6, 1315–1341, 10.1086/285289,
  • JOURNAL, McKenzie, J. A., Batterham, P., 1994, The genetic, molecular and phenotypic consequences of selection for insecticide resistance, Trends in Ecology and Evolution, 9, 5, 166–169, 10.1016/0169-5347(94)90079-5, 21236810,
  • JOURNAL, Reznick, D. N., Bryant, M. J., Roff, D., Ghalambor, C. K., Ghalambor, D. E., 2004, Effect of extrinsic mortality on the evolution of senescence in guppies, Nature, 431, 7012, 1095–1099, 10.1038/nature02936, 15510147, 2004Natur.431.1095R,
  • Rose, M. R., H. B. Passananti, and M. Matos, eds. 2004. Methuselah flies: A case study in the evolution of aging. World Scientific Publishing, Singapore.
  • JOURNAL, Swallow, J. G., Theodore Garland, Jr., Jr, Garland, T., 2005, Selection experiments as a tool in evolutionary and comparative physiology: insights into complex traits — An introduction to the symposium,weblink Integrative and Comparative Biology, 45, 3, 387–390, 10.1093/icb/45.3.387, 21676784,

External links



- content above as imported from Wikipedia
- "experimental evolution" does not exist on GetWiki (yet)
- time: 9:57am EDT - Tue, Aug 20 2019
[ this remote article is provided by Wikipedia ]
LATEST EDITS [ see all ]
GETWIKI 09 JUL 2019
Eastern Philosophy
History of Philosophy
GETWIKI 09 MAY 2016
GETWIKI 18 OCT 2015
M.R.M. Parrott
Biographies
GETWIKI 20 AUG 2014
GETWIKI 19 AUG 2014
CONNECT