What It Means to be 98% Chimpanzee

Arguments about the biological basis of human behavior have become increasingly influential in popular and scientific writing in recent years. In What It Means To Be 98% Chimpanzee: Apes, People, and Their Genes, author Jonathan Marks responds that the apparently scientific character of molecular anthropology, the reduction of human evolutionary traits to molecular genetics, is misleading. He maintains that biological interpretations of human behavior frequently use “folk anthropology,” ideas about people based on cultural and political preconceptions, to shape judgements based on social preconceptions.

Marks begins with the celebrated finding that humans and chimpanzees share the same structure for 98% of their DNA. He points out that this percentage can vary, depending on what aspects of DNA are used as the basis for comparison. Marks goes on to look at how cultural views shape other attempts to reduce human behavior to a supposed genetic basis. One of his particular targets is The Bell Curve, the 1994 book by Richard Herrnstein and Charles Murray that viewed contemporary socioeconomic status as largely a product of genetically determined intelligence. Marks also engages in an extended criticism of the attempt of scientists to use racial classifications as a strategic weapon in the struggles with Native American tribes over ancient skeletal remains in the Kennewick Man controversy of the 1990’s. Ultimately, Marks returns to the chimpanzees and concludes that the 98% similarity is scientifically meaningless.

Marks writes with a lively, if sometimes combative and sarcastic, style. His demand that all genetic arguments about human behavior be supported with direct genetic evidence may be overly strict, since this amounts to assuming purely cultural and historical causes unless biological causes can be definitively proven. Still, this book should be read by all who are interested in current debates over topics such as sociobiology and evolutionary psychology.