Temporal range: Pleistocene - Present
|General idea of an early modern European male|
Homo is the human genus, which also includes Neanderthals and many other extinct species of hominid; H. sapiens is the only surviving species of the genus Homo. Modern humans are sometimes called "anatomically modern humans". Homo sapiens considers itself the most influential species on the planet. However, many kinds of life, especially plants and protists, have had a much greater effect on the air, the rocks and the life on Earth.
Origin[change | change source]
The recent African origin of modern humans is the mainstream model describing the origin and dispersal of anatomically modern humans.
The hypothesis that humans have a single origin was published in Charles Darwin's The Descent of Man (1871). The concept is supported by a study of present-day mitochondrial DNA, and with evidence based on physical anthropology of fossil humans. According to genetic and fossil evidence, older versions of Homo sapiens evolved only in Africa, between 200,000 and 100,000 years ago, with members of one branch leaving Africa by 60,000 years ago and over time replacing earlier human populations such as Neanderthals and Homo erectus.
Sequencing of the full Neanderthal genome suggests Neanderthals and some modern humans share some ancient genetic lineages. The authors of the study suggest that their findings are consistent with Neanderthal admixture of up to 4% in some populations. The reason for this admixture is not known. In August 2012, a study suggested that the DNA overlap is a remnant of a common ancestor of both Neanderthals and modern humans.
Evolution[change | change source]
- Further information: Human evolution
Scientific study of human evolution is mostly concerned with the development of the genus Homo, but usually involves studying other hominids and hominines as well, such as Australopithecus. "Modern humans" are defined as the Homo sapiens species, of which the only living subspecies is known as Homo sapiens sapiens.
Homo sapiens idaltu, the other known subspecies, is now extinct. 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.
Similarly, the discovered specimens of the Homo rhodesiensis species have been classified by some as a subspecies, but this classification is not widely accepted.
Anatomically modern humans first appear in the fossil record in Africa about 195,000 years ago, and studies of molecular biology give evidence that the approximate time of divergence from the common ancestor of all modern human populations was 200,000 years ago. The broad study of African genetic diversity found the ǂKhomani San people had the greatest genetic diversity among the 113 distinct populations sampled, making 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.
References[change | change source]
- Global Mammal Assessment Team (2008). Homo sapiens. 2008 IUCN Red List of Threatened Species. IUCN 2008. Retrieved on 12 February 2015.
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