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 for much of the diversity of life. It is Behe's second intelligent design book, his first being "Darwin's Black Box". While the book has been well received by creationists and non-biologists, reviews by certain scientists, especially those working in the field of biology, have been highly critical of Behe's methods, information and conclusions in the book. Behe begins the book with an observation that the theory of evolution consists of a coherent relationship of three related ideas: common descent, natural selection, and random mutation. He continues by stating he believes they are distinct ideas, with implications for the theory as