His published works include Evolutionary Anthropology (1991, with Edward Staski), Human Biodiversity (1995), and What It Means to be 98% Chimpanzee (2002), and many scholarly articles and essays. He is an outspoken critic of scientific racism, and has prominently argued against the idea that "race" is a natural category. In Marks's view, "race" is a negotiation between patterns of biological variation and patterns of perceived difference.
He is also on the Board of Directors of the Indigenous Peoples Council on Biocolonialism, Nixon, NV.