Gene-centered view of evolution Richard Dawkins and George C. Williams, other biologists and philosophers have expanded and refined the selfish-gene theory, such as John Maynard Smith, George R. Price, Robert Trivers, David Haig, Helena Cronin, David Hull, Philip Kitcher, and Daniel C. Dennett. The gene-centric view has been opposed by Ernst Mayr, Stephen Jay Gould, David Sloan Wilson, and philosopher Elliott Sober. An alternative, multilevel selection (MLS), has been advocated by E. O. Wilson, David Sloan Wilson, Sober, Richard E. Michod, and Samir Okasha. Writing in the "New York Review of Books", Gould has characterized the gene-centered perspective as confusing book-keeping with causality. Gould
Evolution of the brain evolution once the divergence between chimpanzees and humans had already occurred. Each of the gene sequences went through specific changes that led to the evolution of humans from ancestral relatives. In order to determine these alterations, Lahn and his colleagues used DNA sequences from multiple primates then compared and contrasted the sequences with those of humans. Following this step, the researchers statistically analyzed the key differences between the primate and human DNA to come to the conclusion, that the differences were due to natural selection. The changes in DNA sequences of these genes accumulated to bring about a competitive advantage