Human evolution

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Higher topics: History, Biology
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Fossil hominid evolution display at The Museum of Osteology in Oklahoma City, USA.

Wikipedia: Human evolution

Human evolution is the evolutionary process that led to the emergence of anatomically modern humans. The topic typically focuses on the evolutionary history of the primates, rather than studying the earlier history that led to the primates.
Genetic studies show that primates diverged from other mammals about 85 million years ago.
The earliest documented representative of the genus Homo[1] is Homo habilis, which evolved around 2.8 million years ago, and is arguably the earliest species for which there is positive evidence of the use of stone tools. The brains of these early hominins[2] were about the same size as that of a chimpanzee.
With the arrival of Homo erectus and Homo ergaster in the fossil record, cranial capacity had doubled to 850 cm3.
According to the recent African origin of modern humans theory, modern humans evolved in Africa and migrated out of the continent some 50,000 to 100,000 years ago, gradually replacing local populations of Homo erectus, Denisova hominins, Homo floresiensis and Homo neanderthalensis.[3]


Australopithecus 4 million BP

Australopithecus family

Wikipedia: Australopithecus

Australopithecus is an extinct genus of hominins (Homo and Australopithecus). From paleontological and archaeological evidence, the Australopithecus genus apparently evolved in eastern Africa around 4 million years ago before spreading throughout the continent and eventually becoming extinct somewhat after two million years ago.


Homo habilis 2.8-1.5 million BP

File:Homo habilis.JPG
Reconstruction of Homo habilis at the Westfälisches Museum für Archäologie, Herne

Wikipedia: Homo habilis

Homo habilis (also Australopithecus habilis) is a species of the Hominini tribe, which lived from approximately 2.33 to 1.44 million years ago. Its brain size has been shown to range from 550 cm3 to 687 cm3, rather than from 363 cm3 to 600 cm3 as formerly thought. These more recent findings concerning brain size favor its traditional placement in the genus Homo. H. habilis was short and had disproportionately long arms compared to modern humans. H. habilis had a cranial capacity slightly less than half of the size of modern humans. Despite the ape-like morphology of the bodies, H. habilis remains are often accompanied by primitive stone tools (e.g. Olduvai Gorge, Tanzania and Lake Turkana, Kenya).


Homo rudolfensis 1.9 million BP

Homo rudolfensis, Naturhistorisches Museum, Braunschweig, Germany

Wikipedia: Homo rudolfensis

Homo rudolfensis (also Australopithecus rudolfensis) is an extinct species of the Hominini tribe known only through a handful of representative fossils, discovered on the east side of Lake Rudolf (now Lake Turkana) in Kenya.


Homo ergaster in East and South Africa 1.9-1.4 million BP

Homo ergaster head CC.jpg

Wikipedia: Homo ergaster

Homo ergaster (meaning "working man") or African Homo erectus is an extinct chronospecies of the genus Homo that lived in eastern and southern Africa between 1.9 million and 1.4 million years ago. It is one of the earliest hominins, which are those hominids that comprise the original members and species of the human clade after splitting from the line of the chimpanzees. (And Homo ergaster is variously thought to be ancestral to, or as sharing a common ancestor with, or as being the same species as, Homo erectus).


Homo erectus 1.9-0.07 million BP

Wikipedia: Homo erectus

Homo erectus (meaning "upright man", from the Latin ērigere, "to put up, set upright") is an extinct species of hominid that lived throughout most of the Pleistocene geological epoch. Its earliest fossil evidence dates to 1.9 million years ago and the most recent to 70,000 years ago. It is generally thought that H. erectus originated in Africa and spread from there, migrating throughout Eurasia as far as Georgia, India, Sri Lanka, China and Indonesia. But other scientists posit that the species rose first, or separately, in Asia.


Homo antecessor 1.2-0.8 million BP

Reconstruction of a male Homo antecessor

Wikipedia: Homo antecessor

Homo antecessor is an extinct human species (or subspecies) dating from 800,000 to 1.2 million years ago. The species must be related to Out of Africa I, the first series of hominin expansions into Eurasia, making it one of the earliest known human species in Europe. Various archaeologists and anthropologists have debated how H. antecessor relates to other Homo species in Europe, with suggestions that it was an evolutionary link between H. ergaster and H. heidelbergensis.


Homo heidelbergensis 0.6-0.2 million BP

Homo heidelbergensis - forensic facial reconstruction

Wikipedia: Homo heidelbergensis

Homo heidelbergensis – also Homo rhodesiensis – is an extinct species of the genus Homo that lived in Africa, Europe and western Asia between 600 and 200 thousand years ago. The skulls of this species share features with both Homo erectus and anatomically modern Homo sapiens; its brain was nearly as large as that of Homo sapiens. The great majority of fossils attributed to Homo heidelbergensis have [only] been obtained recently, beginning in 1997.
Neanderthals, Denisovans, and modern humans are all considered to have descended from Homo heidelbergensis that appeared around 700,000 years ago in Africa.


Archaic humans 500,000 BP

Anatomical comparison of the skulls of anatomically modern humans "wise men" (left) and Homo neanderthalensis (right)

Wikipedia: Archaic humans

A number of varieties of Homo are grouped into the broad category of archaic humans in the period beginning 500,000 years ago. It typically includes Homo neanderthalensis, Homo rhodesiensis, Homo heidelbergensis, and may also include Homo antecessor. This category is contrasted with anatomically modern humans, which include Homo sapiens sapiens and Homo sapiens idaltu.
Modern humans are theorized to have evolved from archaic humans, who in turn evolved from Homo erectus. Varieties of archaic humans are sometimes included under the binomial name "Homo sapiens" because their brain size is very similar to that of modern humans. Archaic humans had a brain size averaging 1200 to 1400 cubic centimeters, which overlaps with the range of modern humans. Archaics are distinguished from anatomically modern humans by having a thick skull, prominent brow ridges and the lack of a prominent chin.


Homo neanderthalensis 250,000-40,000 BP

Wikipedia: Neanderthal

Neanderthals were a species or subspecies of human in the genus Homo which became extinct around 40,000 years ago. They were closely related to modern humans, having DNA over 99.5% the same. Remains left by Neanderthals include bone and stone tools, which are found in Eurasia, from Western Europe to Central, Northern, and Western Asia.
Neanderthals were large compared to Homo sapiens. With an average cranial capacity of 1600 cm3, the cranial capacity of Neanderthals is notably larger than the 1400 cm3 average for modern humans, indicating that their brain size was larger. Males stood 164–168 cm (65–66 in) and females 152–156 cm (60–61 in) tall.
Neanderthals contributed to the DNA of modern humans, including most non-Africans as well as a few African populations, through interbreeding, likely between 50,000 to 60,000 years ago.
Neanderthals practiced burial behavior and intentionally buried their dead.


Denisovan 125,000-40,000 BP

The geographic spread of Denisovans compared with other groups

Wikipedia: Denisovan

Denisovan or Denisova hominin is an extinct species of human in the genus Homo. In March 2010, scientists announced the discovery of a finger bone fragment of a juvenile female who lived about 41,000 years ago, found in the remote Denisova Cave in the Altai Mountains in Siberia, a cave which has also been inhabited by Neanderthals and modern humans.
Denisovans shared a common origin with Neanderthals, they ranged from Siberia to South-East Asia, and they lived among and interbred with the ancestors of some modern humans, with about 3% to 5% of the DNA of Melanesians and Aboriginal Australians deriving from Denisovans.


Red Deer Cave people 14,500-11,500 BP

Artist's impression

Wikipedia: Red Deer Cave people

The Red Deer Cave People were the most recent known prehistoric population that do not resemble modern humans. Fossils between 14,500 and 11,500 years old were found in Red Deer Cave and Longlin Cave in China. Having a mix of archaic and modern features, they are (tentatively) thought to be a separate species of humans that persisted until recent times and became extinct without contributing to the gene pool of modern humans. Evidence shows large deer were cooked in the Red Deer Cave, giving the people their name.


Wikipedia: List of human evolution fossils (updating)


References

  1. Homo is the genus that comprises the species Homo sapiens, which includes modern humans, as well as several extinct species classified as ancestral to or closely related to modern humans.
  2. The group consisting of modern humans, extinct human species and all our immediate ancestors.
  3. Wikipedia, Human evolution

External links

  • Human evolution - Wikipedia - Human evolution is the evolutionary process that led to the emergence of anatomically modern humans. The topic typically focuses on the evolutionary history of the primates—in particular the genus Homo, and the emergence of Homo sapiens as a distinct species of the hominids (or "great apes")—rather than studying the earlier history that led to the primates. The study of human evolution involves many scientific disciplines, including physical anthropology, primatology, archaeology, paleontology, ethology, linguistics, evolutionary psychology, embryology and genetics.
  • Timeline of human evolution - Wikipedia - The timeline of human evolution outlines the major events in the development of the human species, Homo sapiens, and the evolution of human ancestors. It includes brief explanations of some of the species, genera, and the higher ranks of taxa that are seen today as possible ancestors of modern humans.