Despite the great impact that the Darwinian theories on organic evolution have had in the development and consolidation of biology as an autonomous scientific discipline, their relevance in social sciences, and particularly in archaeology and anthropology still remain ambiguous. This ambiguity is reflected in the classical interpretation of Darwin's work pervading Social Sciences during more than one century, according to which the same ideas that contributed to the understanding of natural processes from a scientific perspective would be at the basis of a misleading interpretation of the evolution of human societies due to the application of the principie of natural selection to the social processes. Here we show how the works of T.H. Huxley and A.R. Wallace positively stimulated Darwin to answer to the question about the origin of human populations considering culture from an evolutionary perspective as a factor opposed to the negative action of natural selection on human societies, thus refuting the classical interpretation of Darwin's work made by Social Sciences. The role played by the biocultural approach in understanding human evolution as well as in promoting the integrative thinking in Social Sciences is also discussed.