In this conversation, I discuss “cultural evolution” with Alex Mesoudi. The very term can be confusing and perplexing to some. After all, it seems intuitive that culture evolves and changes. But here Mesoudi and I discuss the science of cultural evolution, which is today a robust and interdisciplinary field (also see my conversation with Richard McElreath). Why do cultures vary? How fast and why do they change? What is the relation between genes and cultures? All these are topics that cultural evolution as a field addresses. The origins of cultural evolution go back to the 1970’s and 1980’s, in particular, with the research of three pairs of researchers: L. L. Cavalli-Sforza and Marcus Feldman, Cultural Transmission and Evolution E. O. Wilson and Charles Lumsden, Genes, Mind, and Culture Robert Boyd and Peter Richerson, Culture and Evolutionary Process These scholars understood cultural evolution as a branch of population biology. More precisely, they leveraged evolutionary genetic modes of thinking and models and applied them to cultural processes. Boyd and Richerson in particular have continued working in this area (see Not By Genes Alone) and spawned a whole coterie of scholars. In a wide-ranging conversation, Mesoudi offers his opinion on topics as variegated as reductionism, the importance of theory, group selection, and the utility of memes. Also, I should mention that he’s written the literal book on the topic, Cultural Evolution: How Darwinian Theory Can Explain Human Culture and Synthesize the Social Sciences.