Over-exuberant press accounts of recent genetic linkage studies have led the public to believe that there is a "gay gene," a "gene for novelty-seeking," a "gene for happiness" and a gene for just about every other human idiosyncrasy. But to biologists who study even comparatively simple animals such as the fruit fly, it's laughable to speak of any single gene as determining behavior. Time, Love, Memory, Jonathan Weiner's first book since his Pulitzer Prize-winning The Beak of the Finch, is about a little-known Caltech geneticist named Seymour Benzer and his innovative experiments on bacteria-eating phage and Drosophila fruit flies. By tracing four decades of Benzer's painstaking work, Weiner shows that biology's picture of the relationship between genes and behavior is growing more baroque, not less.

A year after James Watson and Francis Crick solved the structure of DNA in 1953, Benzer proved that genes are physical entities that can be dissected and put back together, a fact that allowed him to draw the first detailed map of a gene's interior. This helped Crick and colleague Sydney Brenner to decipher how DNA's four nucleotides (A, C, G and T) encode amino acids and proteins, and to show that most mutations-whether in phage, flies, or philosophers-are due to simple typographical errors in this code.