 Importantly, the genealogical condition is only a necessary condition, as genealogy unites all the segments of one lineage. The segment of the phylogenetic tree that represents some species taxon begins with a node that represents a lineage-splitting or speciation event. Determining that node requires attention to general speciation theory, which has proposed various competing criteria (Dupré 1993: 48f.; Okasha 2002: 201; Coyne &amp; Orr 2004). In the case of Homo sapiens, it requires attention to the specifics of the human case, which are also controversial (see Crow 2003; Cela-Conde &amp; Ayala 2017: 11ff.). The end point of the segment is marked either by some further speciation event or, as may seem likely in the case of Homo sapiens, by the destruction of the metapopulation. Only when the temporal boundaries of the segment have become determinate would it be possible to adduce sufficient conditions for the existence of such a historical entity. Hence, if “human nature” is understood to pick out the necessary and sufficient conditions that individuate the species taxon Homo sapiens, its content is not only controversial, but epistemically unavailable to us.