George C. Williams, Stony Brook professor, dead at 84

George C. Williams, a longtime Stony Brook University professor whose groundbreaking theories of evolutionary biology sharply altered scientists' ideas about natural selection, died Wednesday at age 84 at an elder care facility in South Setauket.

He had been suffering from an illness related to Parkinson's, according to his widow, Doris.

Williams, known for his astute observations and crisp writing, was intrigued by questions about why humans and other animals age and why individual animals put their lives at risk for members of their species. He wondered why some organisms reproduce sexually and others asexually; why some insects live for a few weeks, while tortoises and redwoods can live for more than 100 years.

His answers came in research papers and books that have been widely studied since he started publishing them 50 years ago.

"George was one of the three or four towering intellects in evolutionary biology in the 20th century," said Stephen Stearns, a professor in Yale University's Department of Ecology and Evolutionary Biology. "He was a man of great intellectual courage who went against the establishment."

For decades, scientists believed that individuals get terminally sick or die of old age in order to make room for younger, vibrant members of the species. But Williams found that species are bent on reproduction, often at the expense of longevity.

Williams explored such theories in "Adaptation and Natural Selection," published in 1966 and still widely credited with shaping such scientists as Richard Dawkins and Stephen Jay Gould.

"George clarified their understanding of evolution," said Douglas Futuyma, a Stony Brook distinguished professor of ecology and human evolution.

In 1960, Williams started teaching at the new State University campus at Stony Brook. He later helped found the school's Department of Ecology and Evolution as well as the Marine Sciences Research Center. He retired in 1990, but continued to write and mentor others.

In 1999, in an honor that many scientists considered belated, the Swedish Royal Academy awarded Williams the Crafoord Prize - considered as prestigious for some subjects as the Nobel Prize.

And, according to Doris, a retired Stony Brook University science librarian, "He was the dearest most considerate loving husband one could have." The couple recently celebrated their 59th wedding anniversary.

Survivors also include a son, Jacques Williams of Surprise, N.Y.; three daughters, Sibyl Costell of Setauket, Phoebe Anderson of Wading River and Judith Pitsiokis of McLean, Va., and nine grandchildren. The family is planning to have a memorial event in October.