George C. Williams

George Christopher Williams (May 12, 1926 – September 8, 2010) was an American evolutionary biologist.
Williams was a professor emeritus of biology at the State University of New York at Stony Brook. He was best known for his critique of group selection, though later in life he recognized that it did sometimes occur. The work of Williams in this area, with W.D. Hamilton, John Maynard Smith and others, led to the development of a gene-centered view of evolution.
In 1999 Williams shared the Crafoord Prize, with Maynard Smith and Ernst Mayr, for developing the concept of evolutionary biology.
Academic work.
Williams' 1957 paper "Pleiotropy, natural selection, and the evolution of senescence" was influential in 20th century evolutionary biology. It contains three important ideas. In this paper Williams proposed that senescence should be generally synchronized by natural selection.
"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 paper also contains the first outline of the idea that natural selection might select for menopause and post-reproductive life in females, although Williams does not explicitly mention grandchildren or the inclusive fitness contribution of grandparenting. By helping grandchildren survive, grandparents promote the survival of an average of one-quarter (1/4) of their own genome.p100
In his first book, "Adaptation and Natural Selection", Williams advocated a "ground rule or perhaps "doctrine" would be a better term ... that adaptation is a special and onerous concept that should only be used where it is really necessary", and, that, when it is necessary, selection among genes or individuals would in general be the preferable explanation for it. This contributed to the development of a gene-centered view of evolution; Richard Dawkins built on Williams' ideas in this area in the book "The Selfish Gene".
Williams was also well known for his work on the evolution of sex, and was an advocate of evolutionary medicine.