George C. Williams | |
|---|---|
 | |
| Born | George Christopher Williams (1926-05-12)May 12, 1926 |
| Died | September 8, 2010(2010-09-08) (aged 84) |
| Alma mater | UCLA |
| Known for | theories of natural selection |
| Awards | Daniel Giraud Elliot Medal(1992) Crafoord Prize(1999) |
| Scientific career | |
| Fields | Biology |
| Institutions | Stony Brook University |
George Christopher Williams (May 12, 1926 – September 8, 2010) was an Americanevolutionary biologist.[1][2][3]
Williams was aprofessor ofbiology at theState University of New York at Stony Brook who was best known for his vigorous critique ofgroup selection. The work of Williams in this area, along withW. D. Hamilton,John Maynard Smith,Richard Dawkins, and others led to the development of thegene-centered view of evolution in the 1960s.
Williams's 1957 paperPleiotropy, Natural Selection, and the Evolution of Senescence is one of the most influential in 20th-century evolutionary biology, and contains at least three foundational ideas.[4] The central hypothesis ofantagonistic pleiotropy remains the prevailing evolutionary explanation of senescence. In this paper Williams was also the first to propose thatsenescence should be generally synchronized bynatural selection. According to this original formulation
... if the adverse genic effects appeared earlier in one system than any other, they would be removed by selection from that system more readily than from any other. In other words, natural selection will always be in greatest opposition to the decline of the most senescence-prone system.
This important concept of synchrony of senescence was taken up a short time later byJohn Maynard Smith, and the origin of the idea is often misattributed to him, including in his obituary in the journalNature.[5] Finally, Williams's 1957 paper was the first to outline the "grandmother hypothesis". Williams's formulation stated that natural selection might select for menopause and post-reproductive life in females (though not explicitly mentioning grandchildren or theinclusive fitness contribution of grand-parenting).
In his first book,Adaptation and Natural Selection (1966), Williams advocated a "ground rule - or perhapsdoctrine would be a better term - ... thatadaptation is a special and onerous concept that should only be used where it is really necessary",[6] and that, when it is necessary,selection amonggenes or individuals would in general be the preferable explanation for it. He elaborated this view in later books and papers, which contributed to the development of a gene-centered view of evolution.Richard Dawkins built upon Williams's ideas around selection and genes in his bookThe Selfish Gene (1976).[7]
Williams was also well known for his work on theevolution of sex, and was an advocate ofevolutionary medicine.
InSex and Evolution (1975), he attempted to explain why many species use exclusive sexual reproduction despite its “twofold cost". He proposed several explanatory models ( “aphid-rotifer model,” the “strawberry-coral model,” and “elm-oyster model"), though found all of them insufficient.[8] He even considered the possibility that sex is a maladaption for some species:
When major taxonomic groups all share a certain feature, it is unlikely that the feature has the same adaptive significance throughout the group. It may even be maladaptive for the majority... The fact that parthenogenesis or its equivalent, if found in a vertebrate population, has always replaced sexual reproduction entirely, is decisive evidence of the maladaptive nature of sexuality in these organisms. (Chapter 9)
In later books, includingNatural Selection: Domains, Levels and Challenges, Williams softened his views on group selection, recognizing thatclade selection,trait group selection andmultilevel selection did sometimes occur in nature, something he had earlier thought to be so unlikely it could be safely ignored.[9][10]
Williams became convinced that the genic neo-Darwinism of his earlier years, while essentially correct as a theory of microevolutionary change, could not account for evolutionary phenomena over longer time scales, and was thus an "utterly inadequate account of the evolution of the Earth's biota" (1992, p. 31). In particular, he became a staunch advocate of clade selection – a generalisation of species selection to monophyletic clades of any rank – which could potentially explain phenomena such as adaptive radiations, long-term phylogenetic trends, and biases in rates of speciation/extinction. In Natural Selection (1992), Williams argued that these phenomena cannot be explained by selectively-driven allele substitutions within populations, the evolutionary mechanism he had originally championed over all others. This book thus represents a substantial departure from the position of Adaptation and Natural Selection.[11]
Williams received aPh.D. in biology from theUniversity of California at Los Angeles in 1955. At Stony Brook he taught courses inmarinevertebrate zoology, and he often usedichthyological examples in his books.
In 1992, Williams was awarded theDaniel Giraud Elliot Medal from theNational Academy of Sciences.[12] He won theCrafoord Prize for Bioscience jointly withErnst Mayr andJohn Maynard Smith in 1999. Richard Dawkins describes Williams as "one of the most respected of American evolutionary biologists".[13]
Williams supervised an undergraduate project in 1985 which consisted of a student, Mitchell Behm, tossing live animals into tubs with domesticated ferrets, which Behm subsequently admitted he partly did "for his own amusement." Dr. Charles Middleton, Director of the Division of Laboratory Animal Resources stated, "If animals are just going to tear each other up, the experiment would not have been approved." Ferrets were illegal in New York at the time, without a license, which neither individual had.
After police investigation, Williams received a formal reprimand from SUNY Stony Brook for never receiving approval because of not detailing the pain of the animals involved, and for allowing non-campus animals to participate. Because the statute of limitations had expired, Williams narrowly escaped strict disciplinary action, in addition to criminal prosecution. Dr. Mark Lerman, Medical Director of Lifeline for Wildlife said there was no justification and that the experiment was completely useless.[14]
The experiments were in direct violation of theAnimal Welfare Act of 1966[15] and itsPHS policy amendment introducing theInstitutional Animal Care and Use Committee model,[16] to which SUNY and all of its researchers were subject in 1988.
