The relationship between cultural anthropology and Darwinism is complex. Contrary to what was once received wisdom, cultural anthropology was not inspired by Darwin's ideas. Many nineteenth-century anthropological arguments predated Darwinism by a century or more. Yet, Darwinians figured prominently in organized anthropology in late-nineteenth century Britain, and when Darwin wrote The Descent of Man he drew upon the writings of an international population of anthropologists – although his most important sources were British. But cultural anthropology changed dramatically at the end of the nineteenth century, when its practitioners left their armchairs and took to the field – and conceptualized cultural variation in terms of Darwinian biogeography. Arguably, these practitioners, such as Baldwin Spencer, were influenced by the Darwin who wrote On the Origin of Species, not the Darwin who wrote The Descent of Man. And the disciplinary result of their labors was paradoxical: cultural anthropology informed by notions derived from Darwinian biology factored biological elements out of explanations of cultural variation.