Human Taxonomy - Current Issues in Human Taxonomy

Current Issues in Human Taxonomy

Generally, humans are considered the only surviving representatives of the genus Homo. Some scientists, however, consider other members of the hominid family (chimpanzees, bonobos, and gorillas) to be so close to humans genetically that they should be classified as Homo.

Scientists have also debated whether any other branches of Homo, such as Neanderthals, should be classified as separate species or subspecies of H. sapiens. These distinctions are connected with two competing theories of human origins, the more common recent single-origin hypothesis (that modern humans represent a distinct gene pool) and the multiregional hypothesis (that modern humans spreading from Africa interbred with local Homo populations). Modern humans have some genes that originally arose in archaic human populations, composing perhaps 5% of our genetic inheritance. (For example, see microcephalin.)

Species within the genus Homo are generally regarded as human. Australopithecines, too, are often referred to as human. Lay people sometimes ask whether the species other than H. sapiens were truly human. Were Neanderthals, for example, actually human or just close to human? This question makes sense in an essentialist philosophy, in which humans have an essential identity, and in which Neanderthals either did or did not share that identity. In religious context, the question might be phrased as "Did Neanderthals have souls?" In natural science, however, the term "human" is seen as a category whose boundaries humans themselves determine. The question, in this context, is not whether this or that species had the quality of being human in some absolute sense, but whether we choose to define the category of human as including that species.