Kevin de Queiroz, a research zoologist and curator at the Smithsonian, delves into the perplexing world of species definitions. He explores the historical evolution of the species concept from Darwin’s ideas to modern taxonomies influenced by genetics. The discussion highlights how hybridization complicates classifications. De Queiroz also challenges the stereotypes surrounding Neanderthals, showcasing their significance in human evolution. With a focus on the dynamic nature of science, he emphasizes the importance of precise species definitions for conservation efforts.