Sociocultural evolution justify new policies such as eugenics. Most 19th-century and some 20th-century approaches aimed to provide models for the evolution of humankind as a single entity. However, most 20th-century approaches, such as multilineal evolution, focused on changes specific to individual societies. Moreover, they rejected directional change (i.e. orthogenetic, teleological or progressive change). Most archaeologists work within the framework of multilineal evolution. Other contemporary approaches to social change include neoevolutionism, sociobiology, dual inheritance theory, modernisation theory and postindustrial theory. In his seminal 1976 book "The Selfish Gene", Richard Dawkins wrote that "there are some examples of cultural evolution in birds and monkeys,
The Edge of Evolution a whole; common descent and natural selection he accepts without question but questions the scope and power of random mutation to produce beneficial mutations that lead to novel, useful structures and processes. He terms "Darwinian evolution" the type of evolution relying on all three of these factors, applies the label "Darwinists" to scientists who hold the view that Darwinian evolution is the only existing form of evolution, and who take exception to intelligent design as well as other theistic and non-theistic complexity theories. Behe's central assertion regarding Darwinian evolution is that it exists, but that it is better at disturbing