In evolutionary biology, group selection refers to the idea that alleles can become fixed or spread in a population because of the benefits they bestow on groups, regardless of the fitness of individuals within that group. Evolutionary biology is a subfield of biology concerned with the origin and descent of species, as well as their change, multiplication, and diversity over time. ... In genetics, an allele (pronounced al-eel or al-e-ul) is any one of a number of viable DNA codings occupying a given locus (position) on a chromosome. ... Fitness (often denoted in population genetics models) is a central concept in evolutionary theory. ...

Group selection was used as a popular explanation for adaptations, especially by V.C. Wynne-Edwards. However, critiques, particularly by George C. Williams in his 1966 book Adaptation and Natural Selection, John Maynard Smith (1964) and C.M. Perrins (1964) cast serious doubt on group selection as a major mechanism of evolution, and led to a more gene-centric view of evolution. Vero Copner Wynne-Edwards (4 July 1906 — January 5, 1997) was a British zoologist best known for espousing group selection, most notably in his 1962 book, Animal Dispersion in Relation to Social Behavior. ... George Williams Professor George Christopher Williams (b. ... 1966 (MCMLXVI) was a common year starting on Saturday (the link is to a full 1966 calendar). ... Cover of the 1996 edition. ... John Maynard Smith Professor John Maynard Smith, F.R.S. (6 January 1920 – 19 April 2004) was a British evolutionary biologist and geneticist. ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... Professor Christopher Miles Chris Perrins, FRS is a British biologist. ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... In 1832, while traveling on the Beagle, naturalist Charles Darwin collected giant fossils in South America. ... The gene-centric view of evolution, gene selection theory or selfish gene theory holds that natural selection acts through differential survival of competing genes, increasing the frequency of those alleles whose phenotypic effects successfully promote their own propagation. ...

Overview

Specific syndromes of selective factors can create situations in which groups are selected because they display group properties which are selected-for. Some mosquito-transmitted rabbit viruses, for instance, are only transmitted to uninfected rabbits from infected rabbits which are still alive. This creates a selective pressure on every group of viruses already infecting a rabbit not to become too virulent and kill their host rabbit before enough mosquitoes have bitten it, since otherwise all the viruses inside the dead rabbit would rot with it. And indeed in natural systems such viruses display much lower virulence levels than do mutants of the same viruses that in laboratory culture readily outcompete non-virulent variants (or than do tick-transmitted viruses -- ticks, unlike mosquitoes, bite dead rabbits).

However, theoretical models of the 1960s seemed to imply that the effect of group selection was negligible. Genetic variation, the raw material of selection, is much higher between individuals than it is between groups, particularly as groups grow larger. Alleles are likely to be held on a population-wide level, leaving nothing for group selection to select for. In addition, most phenotypes, particularly physical ones, are not highly heritable in the first place. Additionally, generation time is much longer for groups than it is for individuals. Assuming conflicting selection pressures, individual selection will occur much faster, swamping any changes potentially favored by group selection. The Price equation can partition variance caused by natural selection at the individual level and the group level, and individual level selection generally causes greater effects. The 1960s decade refers to the years from January 1, 1960 to December 31, 1969, inclusive. ... Genetics (from the Greek genno γεννώ= give birth) is the science of genes, heredity, and the variation of organisms. ... In music, variation is a formal technique where material is altered during repetition; reiteration with changes. ... Selection is hierachically classified into natural and artificial selection. ... In genetics, an allele (pronounced al-eel or al-e-ul) is any one of a number of viable DNA codings occupying a given locus (position) on a chromosome. ... Individuals in the mollusk species Donax variabilis show diverse coloration and patterning in their phenotypes. ... Heritability, as used professionally in genetics, has a very precise definition. ... Evolutionary pressure or selection pressure can be formalized as an external pressure applied to a process, thereby pushing that process in a distinct direction. ... The Price equation (also known as Prices equation) is a covariance equation which is a mathematical description of evolution and natural selection. ...

Experimental results starting in the late 1970s demonstrated that group selection was far more effective than theoretical models ever would have predicted (e.g., Wade 1977). A review of this experimental work has shown that the early group selection models were flawed because they assumed that genes acted independently, whereas in the experimental work it was apparent that gene interaction, and more importantly, genetically based interactions among individuals, were an important source of the response to group selection (e.g., Goodnight and Stevens 1997). As a result many are beginning to recognize that group selection, or more appropriately multilevel selection, is potentially an important force in evolution.

More recently, Yaneer Bar-Yam has claimed that the gene-centered view (and thus Fisher's treatment of evolution) relies upon a mathematical approximation that is not generally valid. Bar-Yam argues that the approximation is a dynamic form of the Mean Field approximation frequently used in physics and whose limitations are recognized there. In biology, the approximation breaks down when there are spatial populations resulting in inhomogeneous genetic types (called symmetry breaking in physics). Such symmetry breaking may also correspond to speciation. A many-body system with interactions is generally very difficult to solve exactly, except for extremely simple cases (Gaussian field theory, 1D Ising model. ... Promotional picture Symmetry Breaking is a rock band from Northern New Jersey, in the United States. ... Charles Darwins first sketch of an evolutionary tree from his First Notebook on Transmutation of Species (1837) Speciation is the evolutionary process by which new biological species arise. ...

Spatial populations of predators and prey have also been shown to show restraint of reproduction at equilibrium, both individually (Rauch et al, 2003) and through social communication (Werfel & Bar-Yam, 2004), as originally proposed by Wynne-Edwards. While these spatial populations do not have well-defined groups for group selection, the local spatial interactions of organisms in transient groups are sufficient to lead to a kind of multi-level selection. There is however as yet no evidence that these processes operate in the situations where Wynne-Edwards posited them; Rauch et al's analysis, for example, is of a host-parasite situation, which was recognised as one where group selection was possible even by E. O. Wilson (1975), in a treatise broadly hostile to the whole idea of group selection. Edward Osborne Wilson (b. ...

Multilevel selection theory

See also Unit of selection. A unit of selection is a biological entity within the hierarchy of biological organisation (e. ...

In recent years, the limitations of earlier models have been addressed, and newer models suggest that selection may sometimes act above the gene level. Recently Elliot Sober and David Sloan Wilson have argued that the case against group selection has been overstated. They focus their argument on whether groups can have functional organization in the same way individuals do and, consequently, if groups can also be "vehicles" for selection. For example, groups that cooperate better may have out-reproduced those which did not. Resurrected in this way, Sober & Wilson's new group selection is usually called multilevel selection theory. Elliott Sober -- Hans Reichenbach Professor and William F. Vilas Research Professor in the Department of Philosophy at University of Wisconsin. ... David Sloan Wilson is an American evolutionary biologist. ... Selection is hierachically classified into natural and artificial selection. ...

Although Richard Dawkins and fellow advocates of the gene-centered view of evolution remain unconvinced (see, for example, Cronk, 1994; Dawkins, 1994; Dennett, 1994), Sober and Wilson's work has been part of a broad revival of interest in multilevel selection as an explanation for evolutionary phenomena. Indeed, in a 2005 article, E. O. Wilson (often regarded as the father of sociobiology) argued that kin selection could no longer be thought of as underlying the evolution of extreme sociality, for two reasons. First, Trivers and others have shown that the argument that haplodiploid inheritance, characteristic of the Hymenoptera, creates a strong selection pressure towards nonreproductive castes is mathematically flawed ^{[citation needed]}. Secondly, eusociality no longer seems to be confined to the hymenopterans; increasing numbers of highly social taxa have been found in the years since Wilson's foundational text on sociobiology was published in 1975, including a variety of insect species, as well as a rodent species (the naked mole rat). Wilson suggests replacing Hamilton's equation Clinton Richard Dawkins (born March 26, 1941) is a British ethologist, evolutionary biologist and popular science writer who holds the Charles Simonyi Chair for the Public Understanding of Science at Oxford University. ... Robert L. Trivers, (born 19 February 1943) is an American evolutionary biologist and sociobiologist, most noted for proposing the theories of reciprocal altruism (1971), parental investment (1972), and parent-offspring conflict (1974). ... Suborders Apocrita Symphyta Many families, see article Hymenoptera is one of the larger orders of Insects, comprising the sawflies, wasps, bees, and ants. ... Binomial name Heterocephalus glaber Rüppell, 1842 The Naked Mole Rat (Heterocephalus glaber), also known as the Sand Puppy, or desert mole rat, is a very unusual burrowing rodent native to parts of East Africa, predominately South Ethiopia, Kenya, and Somalia. ...

(where b represents the benefit to the recipient of altruism, c the cost to the altruist, and r their degree of relatedness) should be replaced by the more general equation

in which b_k is the benefit to kin (b in the original equation) and b_e is the benefit accruing to the group as a whole. He then argues that, in the present state of the evidence in relation to social insects, it appears that b_e>>rb_k, so that altruism needs to be explained in terms of selection at the colony level rather than at the kin level.

However, even more recently, it has been argued that EO Wilson made a series of basic errors in logic in making these arguments and that kin selection and group selection are, in fact, not in opposition at all (Foster et al. 2006).

References

• Dawkins, R. (1994). Burying the Vehicle. Commentary on Wilson & Sober: Group Selection. Behavioural and Brain Sciences. 17 (4): 616-617. link
• Dennett, D.C. (1994). E Pluribus Unum? Commentary on Wilson & Sober: Group Selection. Behavioural and Brain Sciences. 17 (4): 617-618. link
• Foster, KR, Wenseleers T, and Ratnieks FLW 2006. Kin selection is the key to altruism. Trends in Ecology and Evolution, 21:57 - 60
• Goodnight, C. J. and L. Stevens. 1997. Experimental studies of group selection: What do they tell us about group selection in nature. American Naturalist 150:S59-S79.
• Hamilton, W.D. (1964) The evolution of social behavior Journal of Theoretical Biology 1:295–311
• Maynard Smith, J. (1964) Group selection and kin selection Nature 201:1145-1147
• Rauch, E. M., Sayama, H., & Bar-Yam, Y. (2003). Dynamics and genealogy of strains in spatially extended host-pathogen models. Journal of Theoretical Biology, 221, 655-664.
• Wade, M. J. 1977. An experimental study of group selection. Evolution 31:134-153
• Werfel, J., & Bar-Yam, Y. (2004). The evolution of reproductive restraint through social communication. Proceedings of the National Academy Of Sciences Of The United States Of America, 101, 11019-1102.
• Williams, G.C. (1972) Adaptation and Natural Selection: A Critique of Some Current Evolutionary Thought . Princetown UP.ISBN 0-691-02357-3
• Williams, G.C. (1971) (ed) Group Selection
• Williams, G.C. (1986) Evolution Through Group Selection.Blackwell. ISBN 0-632-01541-1
• Wilson, D.S. & Sober, E. 1994. Reintroducing group selection to the human behavioral sciences. Behavioral and Brain Sciences 17 (4): 585-654. link
• Wilson, E. O. (2005). Kin Selection as the Key to Altruism: its Rise and Fall. "Social Research" 72 (1): 159-166.
• Wynne-Edwards, V.C. (1962). Animal Dispersion in Relation to Social Behaviour. Edinburgh: Oliver & Boyd.
• Wynne-Edwards, V. C. (1986) Evolution Through Group Selection, Blackwell. ISBN 0-632-01541-1

Clinton Richard Dawkins (born March 26, 1941) is a British ethologist, evolutionary biologist and popular science writer who holds the Charles Simonyi Chair for the Public Understanding of Science at Oxford University. ... Daniel Clement Dennett (b. ... This article is about the British biologist Bill Hamilton. ... The Evolution of Social Behavior is a 1964 scientific paper by the British evolutionary biologist W.D. Hamilton in which he lays out a kin selection. ... The Journal of Theoretical Biology is a scientific journal dealing with all mathematical and computational aspects of biology. ... John Maynard Smith Professor John Maynard Smith, F.R.S. (6 January 1920 – 19 April 2004) was a British evolutionary biologist and geneticist. ... First title page, November 4, 1869 Nature is one of the oldest and most reputable scientific journals, first published on 4 November 1869. ... George Williams Professor George Christopher Williams (b. ... E.O. Wilson with Dynastes hercules E. O. Wilson, or Edward Osborne Wilson, (born June 10, 1929) is an entomologist and biologist known for his work on ecology, evolution, and sociobiology. ... Vero Copner Wynne-Edwards (4 July 1906 — January 5, 1997) was a British zoologist best known for espousing group selection, most notably in his 1962 book, Animal Dispersion in Relation to Social Behavior. ...

External links

• The Controversy of the Group Selection Theory - a review from the Science Creative Quarterly