Modern synthesis (20th century) a gene-centred view of evolution following Hamilton's concepts, disputing the idea of evolutionary progress, and attacking the then widespread theory of group selection. Williams argued that natural selection worked by changing the frequency of alleles, and could not work at the level of groups. Gene-centred evolution was popularised by Richard Dawkins in his 1976 book "The Selfish Gene" and developed in his more technical writings. In 1975, E. O. Wilson published his controversial book "", the subtitle alluding to the modern synthesis as he attempted to bring the study of animal society into the evolutionary fold. This appeared radically new,
Feathers: The Evolution of a Natural Miracle published by the National Audubon Society. "Feathers" is Hanson's second book, after "The Impenetrable Forest: My Gorilla Years in Uganda" (2008). Following a preface and introduction, "Feathers" is divided into five main parts: "Evolution" discusses the evolutionary history of feathers, "Fluff" explains the role of feathers in regulating body temperature, "Flight" discusses the origin of avian flight as well as its impact on human aviation, "Fancy" discusses the role of feathers in sexual selection and human fashion, and "Function" discusses the continuing evolution of feathers in both nature and human usage. "Feathers" begins with the 1861 discovery of the first