Homo sapiens

Sequencing of the full Neanderthal genome suggests Neanderthals and some modern humans share some ancient genetic lineages. Some populations may have as much as 4% Neanderthal DNA, according to the authors of this study. The reason for this admixture is not known.^[8]

This DNA overlap may exist because both Neanderthals and modern humans had a common ancestor, according to an August 2012 study.^[9][10]

Within the Homo sapiens species, modern humans belong to the only living subspecies: Homo sapiens sapiens. Homo sapiens idaltu, the other known subspecies, is now extinct.^[11]

Homo neanderthalensis, which became extinct 30,000 years ago, has sometimes been classified as a subspecies, "Homo sapiens neanderthalensis". Genetic studies now suggest that the functional DNA of modern humans and Neanderthals diverged 500,000 years ago.^[12]

Similarly, some scientists have classified the discovered specimens of the Homo rhodesiensis species as a subspecies, but this classification is not widely accepted.

Until recently it was thought that anatomically modern humans first appeared in the fossil record in Africa about 195,000 years ago. However, studies of molecular biology suggest that 200,000 years ago, modern humans diverged from the common ancestor of all human populations.^{[13][14][15][16][17]}

A broad study of African genetic diversity found the ǂKhomani San people had the greatest genetic diversity among the 113 distinct populations sampled. This makes them one of 14 "ancestral population clusters". The research also placed the origin of modern human migration in south-western Africa, near the coastal border of Namibia and Angola.^[18][19]

In the 1960s an archaeological site at Jebel Irhoud in Morocco was dated as about 40,000 years old. However, it was re-dated in the 2000s. It is now thought to be between 300,000 and 350,000 years old. The skull form is almost identical to modern humans,^[20] though the jaw is different.

The forces of natural selection have continued to operate on human populations, with evidence that certain regions of the genome show selection in the past 15,000 years.^[21]