1917-1998

American molecular biologist who during the 1980s adopted a controversial technique for comparing the DNA of different species to document ranges of genetic differences. Sibley applied this technique to the problem of human-chimp-gorilla phylogeny. He reported that humans were, genetically, closer relatives to chimpanzees than to gorillas; it was previously thought that humans were equally related to both. In a series of papers, Sibley claimed that his procedure was genetic, precise, replicable, and quantitative. However, his work was subsequently discredited.