he present paper asserts that groups such as Neandertals and Denisovans should be considered subspecies of H. sapiens. This contention is based upon the biological species concept and the fact that these groups interbred to create viable offspring. It is also stated that introgression from these groups made several positive contributions to the evolution of H. sapiens and their genome that may have served to promote the persistence of H. sapiens in Eurasia
