Human evolution

Human evolution
Reconstruction of Homo heidelbergensis which may be the direct ancestor of both Homo neanderthalensis and Homo sapiens.

Human evolution refers to the evolutionary history of the genus Homo, including the emergence of Homo sapiens as a distinct species and as a unique category of hominids ("great apes") and mammals. The study of human evolution uses many scientific disciplines, including physical anthropology, primatology, archaeology, linguistics and genetics.[1]

The term "human" in the context of human evolution refers to the genus Homo, but studies of human evolution usually include other hominids, such as the Australopithecines, from which the genus Homo diverged by about 2.3 to 2.4 million years ago in Africa.[2][3] Scientists have estimated that humans branched off from their common ancestor with chimpanzees about 5–7 million years ago. Several species and subspecies of Homo evolved and are now extinct, introgressed or extant. Examples include Homo erectus (which inhabited Asia, Africa, and Europe) and Neanderthals (either Homo neanderthalensis or Homo sapiens neanderthalensis) (which inhabited Europe and Asia). Archaic Homo sapiens, the forerunner of anatomically modern humans, evolved between 400,000 and 250,000 years ago.

One view among scientists concerning the origin of anatomically modern humans is the hypothesis known as "Out of Africa", recent African origin of modern humans, or recent African origin hypothesis,[4][5][6] which argues that Homo sapiens arose in Africa and migrated out of the continent around 50,000 to 100,000 years ago, replacing populations of Homo erectus in Asia and Neanderthals in Europe. An alternative multiregional hypothesis posits that Homo sapiens evolved as geographically separate but interbreeding populations stemming from the worldwide migration of Homo erectus out of Africa nearly 2.5 million years ago. Evidence suggests that several haplotypes of Neanderthal origin are present among all non-African populations, and Neanderthals and other hominids, such as Denisova hominin may have contributed up to 6% of their genome to present-day humans.[7][8][9]

Contents

History of ideas

The word homo, the name of the biological genus to which humans belong, is Latin for "human". It was chosen originally by Carolus Linnaeus in his classification system. The word "human" is from the Latin humanus, the adjectival form of homo. The Latin "homo" derives from the Indo-European root *dhghem, or "earth".[10]

Carolus Linnaeus and other scientists of his time also considered the great apes to be the closest relatives of humans due to morphological and anatomical similarities. The possibility of linking humans with earlier apes by descent only became clear after 1859 with the publication of Charles Darwin's On the Origin of Species. This argued for the idea of the evolution of new species from earlier ones. Darwin's book did not address the question of human evolution, saying only that "Light will be thrown on the origin of man and his history".

The first debates about the nature of human evolution arose between Thomas Huxley and Richard Owen. Huxley argued for human evolution from apes by illustrating many of the similarities and differences between humans and apes, and did so particularly in his 1863 book Evidence as to Man's Place in Nature. However, many of Darwin's early supporters (such as Alfred Russel Wallace and Charles Lyell) did not agree that the origin of the mental capacities and the moral sensibilities of humans could be explained by natural selection. Darwin applied the theory of evolution and sexual selection to humans when he published The Descent of Man in 1871.[11]

A major problem at that time was the lack of fossil intermediaries. Despite the discovery by Eugene Dubois of what is now called Homo erectus in 1891 at Trinil, Java, it was only in the 1920s that such fossils were discovered in Africa, that intermediate species began to accumulate. In 1925, Raymond Dart described Australopithecus africanus. The type specimen was the Taung Child, an Australopithecine infant discovered in a cave. The child's remains were a remarkably well-preserved tiny skull and an endocranial cast of the individual's brain. Although the brain was small (410 cm³), its shape was rounded, unlike that of chimpanzees and gorillas, and more like a modern human brain. Also, the specimen showed short canine teeth, and the position of the foramen magnum was evidence of bipedal locomotion. All of these traits convinced Dart that the Taung baby was a bipedal human ancestor, a transitional form between apes and humans.

The classification of humans and their relatives has changed considerably since the 1950s.[12] For instance; gracile Australopithecines was thought to be ancestors of the genus Homo, the group to which modern humans belong.[13] Both Australopithecines and Homo sapiens are part of the tribe Hominini.[14]

Data collected during the 1970s suggests Australopithecines were a diverse group and that A. africanus may not be a direct ancestor of modern humans.[15] Reclassification of Australopithecines that originally were split into either gracile or robust varieties has put the latter into a genus of its own, Paranthropus.[15] Taxonomists place humans, Australopithecines and related species in the same family as other great apes, in the Hominidae. Richard Dawkins in his book The Ancestor's Tale proposes that robust Australopithecines: Paranthropus, are the ancestors of gorillas, whereas some of the gracile australopithecus are the ancestors of chimpanzees, the others being human ancestors (see Homininae).[14]

Progress throughout the 1980s and 1990s in DNA sequencing, specifically mitochondrial DNA (mtDNA) and then Y-chromosome DNA advanced the understanding of human origins.[16][17][18] Sequencing mtDNA and Y-DNA sampled from a wide range of indigenous populations revealed ancestral information relating to both male and female genetic heritage.[19] Aligned in genetic tree differences were interpreted as supportive of a recent single origin.[20] Analysis have shown a greater diverse of DNA pattern throughout Africa, thus indicating its the ancestral home of mitochondrial Eve and Y-chromosomal Adam.[21]


Hominin species distributed through time edit

Homo Australopithecus Ardipithecus Paranthropus Homo sapiens Homo neandertalensis Homo heidelbergensis Homo erectus Paranthropus robustus Paranthropus boisei Paranthropus aethiopicus Homo ergaster Homo habilis Australopithecus sediba Australopithecus garhi Australopithecus africanus Australopithecus bahrelghazali Australopithecus afarensis Australopithecus anamensis Orrorin tugenensis Sahelanthropus Pleistocene Pliocene Miocene


Before Homo

Evolution of the great apes

Plesiadapis

The evolutionary history of the primates can be traced back 65 million years, as one of the oldest of all surviving placental mammal groups. The oldest known primate-like mammal species, the Plesiadapis, came from North America, but they were widespread in Eurasia and Africa during the tropical conditions of the Paleocene and Eocene.

Notharctus

The beginning of modern climates was marked by the formation of the first Antarctic ice in the early Oligocene around 30 million years ago. A primate from this time was Notharctus. Fossil evidence found in Germany in the 1980s was determined to be about 16.5 million years old, some 1.5 million years older than similar species from East Africa and challenging the original theory regarding human ancestry originating on the African continent.

David Begun[22] says that these primates flourished in Eurasia and that the lineage leading to the African apes and humans—including Dryopithecus—migrated south from Europe or Western Asia into Africa. The surviving tropical population, which is seen most completely in the upper Eocene and lowermost Oligocene fossil beds of the Fayum depression southwest of Cairo, gave rise to all living primates—lemurs of Madagascar, lorises of Southeast Asia, galagos or "bush babies" of Africa, and the anthropoids; platyrrhines or New World monkeys, and catarrhines or Old World monkeys and the great apes and humans.

The earliest known catarrhine is Kamoyapithecus from uppermost Oligocene at Eragaleit in the northern Kenya Rift Valley, dated to 24 million years ago.[23] Its ancestry is generally thought to be species related to Aegyptopithecus, Propliopithecus, and Parapithecus from the Fayum, at around 35 million years ago.[24] In 2010, Saadanius was described as a close relative of the last common ancestor of the crown catarrhines, and tentatively dated to 29–28 million years ago, helping to fill an 11-million-year gap in the fossil record.[25]

Reconstructed tailless Proconsul skeleton

In the early Miocene, about 22 million years ago, the many kinds of arboreally adapted primitive catarrhines from East Africa suggest a long history of prior diversification. Fossils at 20 million years ago include fragments attributed to Victoriapithecus, the earliest Old World Monkey. Among the genera thought to be in the ape lineage leading up to 13 million years ago are Proconsul, Rangwapithecus, Dendropithecus, Limnopithecus, Nacholapithecus, Equatorius, Nyanzapithecus, Afropithecus, Heliopithecus, and Kenyapithecus, all from East Africa. The presence of other generalized non-cercopithecids of middle Miocene age from sites far distant—Otavipithecus from cave deposits in Namibia, and Pierolapithecus and Dryopithecus from France, Spain and Austria—is evidence of a wide diversity of forms across Africa and the Mediterranean basin during the relatively warm and equable climatic regimes of the early and middle Miocene. The youngest of the Miocene hominoids, Oreopithecus, is from 9 million year old coal beds in Italy.

Molecular evidence indicates that the lineage of gibbons (family Hylobatidae) became distinct from Great Apes between 18 and 12 million years ago, and that of orangutans (subfamily Ponginae) became distinct from the other Great Apes at about 12 million years; there are no fossils that clearly document the ancestry of gibbons, which may have originated in a so-far-unknown South East Asian hominoid population, but fossil proto-orangutans may be represented by Ramapithecus from India and Griphopithecus from Turkey, dated to around 10 million years ago.[26]

Divergence of the human lineage from other Great Apes

A reconstruction of a female Australopithecus afarensis.

Species close to the last common ancestor of gorillas, chimpanzees and humans may be represented by Nakalipithecus fossils found in Kenya and Ouranopithecus found in Greece. Molecular evidence suggests that between 8 and 4 million years ago, first the gorillas, and then the chimpanzees (genus Pan) split off from the line leading to the humans; human DNA is approximately 98.4% identical to that of chimpanzees when comparing single nucleotide polymorphisms (see human evolutionary genetics). The fossil record of gorillas and chimpanzees is quite limited. Both poor preservation (rain forest soils tend to be acidic and dissolve bone) and sampling bias probably contribute to this problem.

Other hominines likely adapted to the drier environments outside the equatorial belt, along with antelopes, hyenas, dogs, pigs, elephants, and horses. The equatorial belt contracted after about 8 million years ago. Fossils of these hominans - the species in the human lineage following divergence from the chimpanzees - are relatively well known.

The earliest are Sahelanthropus tchadensis (7 Ma) and Orrorin tugenensis (6 Ma), followed by:

Genus Homo

Homo sapiens is the only extant species of its genus, Homo. While some other, extinct Homo species might have been ancestors of Homo sapiens, many were likely our "cousins", having speciated away from our ancestral line.[27][28] There is not yet a consensus as to which of these groups should count as separate species and which as subspecies. In some cases this is due to the dearth of fossils, in other cases it is due to the slight differences used to classify species in the Homo genus.[28] The Sahara pump theory (describing an occasionally passable "wet" Sahara Desert) provides an explanation of the early variation in the genus Homo.

Based on archaeological and paleontological evidence, it has been possible to infer, to some extent, the ancient dietary practices of various Homo species and to study the role of diet in physical and behavioral evolution within Homo.[29][30][31][32][33]

H. habilis and H. gautengensis

A reconstruction of Homo habilis.

Homo habilis lived from about 2.4 to 1.4 Ma. Homo habilis evolved in South and East Africa in the late Pliocene or early Pleistocene, 2.5–2 Ma, when it diverged from the Australopithecines. Homo habilis had smaller molars and larger brains than the Australopithecines, and made tools from stone and perhaps animal bones. One of the first known hominids, it was nicknamed 'handy man' by its discoverer, Louis Leakey due to its association with stone tools. Some scientists have proposed moving this species out of Homo and into Australopithecus due to the morphology of its skeleton being more adapted to living on trees rather than to moving on two legs like Homo sapiens.[34]

It was considered to be the first species of the genus Homo until May 2010, when a new species, Homo gautengensis was discovered in South Africa, that most likely arose earlier than Homo habilis.[35]

H. rudolfensis and H. georgicus

These are proposed species names for fossils from about 1.9–1.6 Ma, the relation of which with Homo habilis is not yet clear.

  • Homo rudolfensis refers to a single, incomplete skull from Kenya. Scientists have suggested that this was another Homo habilis, but this has not been confirmed.[36]
  • Homo georgicus, from Georgia, may be an intermediate form between Homo habilis and Homo erectus,[37] or a sub-species of Homo erectus.[38]

H. ergaster and H. erectus

One current view of the temporal and geographical distribution of hominid populations.[39] Other interpretations differ mainly in the taxonomy and geographical distribution of hominid species.

The first fossils of Homo erectus were discovered by Dutch physician Eugene Dubois in 1891 on the Indonesian island of Java. He originally gave the material the name Pithecanthropus erectus based on its morphology that he considered to be intermediate between that of humans and apes.[40] Homo erectus (H erectus) lived from about 1.8 Ma to about 70,000 years ago (which would indicate that they were probably wiped out by the Toba catastrophe; however, Homo erectus soloensis and Homo floresiensis survived it). Often the early phase, from 1.8 to 1.25 Ma, is considered to be a separate species, Homo ergaster, or it is seen as a subspecies of Homo erectus, Homo erectus ergaster.

In the early Pleistocene, 1.5–1 Ma, in Africa, Asia, and Europe, some populations of Homo habilis are thought to have evolved larger brains and made more elaborate stone tools; these differences and others are sufficient for anthropologists to classify them as a new species, Homo erectus. In addition Homo erectus was the first human ancestor to walk truly upright.[41] This was made possible by the evolution of locking knees and a different location of the foramen magnum (the hole in the skull where the spine enters). They may have used fire to cook their meat.

A famous example of Homo erectus is Peking Man; others were found in Asia (notably in Indonesia), Africa, and Europe. Many paleoanthropologists now use the term Homo ergaster for the non-Asian forms of this group, and reserve Homo erectus only for those fossils that are found in Asia and meet certain skeletal and dental requirements which differ slightly from H. ergaster.

H. cepranensis and H. antecessor

These are proposed as species that may be intermediate between H. erectus and H. heidelbergensis.

H. heidelbergensis

H. heidelbergensis (Heidelberg Man) lived from about 800,000 to about 300,000 years ago. Also proposed as Homo sapiens heidelbergensis or Homo sapiens paleohungaricus.[45]

H. rhodesiensis, and the Gawis cranium

  • H. rhodesiensis, estimated to be 300,000–125,000 years old. Most current experts believe Rhodesian Man to be within the group of Homo heidelbergensis, though other designations such as Archaic Homo sapiens and Homo sapiens rhodesiensis have also been proposed.
  • In February 2006 a fossil, the Gawis cranium, was found which might possibly be a species intermediate between H. erectus and H. sapiens or one of many evolutionary dead ends. The skull from Gawis, Ethiopia, is believed to be 500,000–250,000 years old. Only summary details are known, and no peer reviewed studies have been released by the finding team. Gawis man's facial features suggest its being either an intermediate species or an example of a "Bodo man" female.[46]

H. neanderthalensis

Dermoplastic reconstruction of a Neanderthal.

H. neanderthalensis lived from 400,000[47] to about 30,000 years ago. Also proposed as Homo sapiens neanderthalensis.[48] Evidence from sequencing mitochondrial DNA indicated that no significant gene flow occurred between H. neanderthalensis and H. sapiens, and, therefore, the two were separate species that shared a common ancestor about 660,000 years ago.[49][50] In 1997, Mark Stoneking stated: "These results [based on mitochondrial DNA extracted from Neanderthal bone] indicate that Neanderthals did not contribute mitochondrial DNA to modern humans… Neanderthals are not our ancestors". Subsequent investigation of a second source of Neanderthal DNA supported these findings.[51]

However, the 2010 sequencing of the Neanderthal genome indicated that Neanderthals did indeed interbreed with H. sapiens circa 45,000 to 80,000 years ago (after H. sapiens moved out from Africa, but before they separated into Europe, Asia and elsewhere).[52] Nearly all modern non-African humans have 1% to 4% of their DNA derived from Neanderthal DNA.[52] However, supporters of the multiregional hypothesis point to recent studies indicating non-African nuclear DNA heritage dating to one Ma,[53] although the reliability of these studies has been questioned.[54] Competition from Homo sapiens probably contributed to Neanderthal extinction.[55][56] They could have coexisted in Europe for as long as 10,000 years.[57]

H. sapiens

H. sapiens (the adjective sapiens is Latin for "wise" or "intelligent") have lived from about 250,000 years ago to the present. Between 400,000 years ago and the second interglacial period in the Middle Pleistocene, around 250,000 years ago, the trend in skull expansion and the elaboration of stone tool technologies developed, providing evidence for a transition from H. erectus to H. sapiens. The direct evidence suggests there was a migration of H. erectus out of Africa, then a further speciation of H. sapiens from H. erectus in Africa. A subsequent migration within and out of Africa eventually replaced the earlier dispersed H. erectus. This migration and origin theory is usually referred to as the recent single origin or Out of Africa theory. Current evidence does not preclude some multiregional evolution or some admixture of the migrant H. sapiens with existing Homo populations. This is a hotly debated area of paleoanthropology.

Current research has established that humans are genetically highly homogenous; that is, the DNA of individuals is more alike than usual for most species, which may have resulted from their relatively recent evolution or the possibility of a population bottleneck resulting from cataclysmic natural events such as the Toba catastrophe.[58][59][60] Distinctive genetic characteristics have arisen, however, primarily as the result of small groups of people moving into new environmental circumstances. These adapted traits are a very small component of the Homo sapiens genome, but include various characteristics such as skin color and nose form, in addition to internal characteristics such as the ability to breathe more efficiently at high altitudes.

H. sapiens idaltu, from Ethiopia, is an extinct sub-species who lived about 160,000 years ago.

H. floresiensis

Reconstruction of the female's head of an Homo floresiensis.

H. floresiensis, which lived from approximately 100,000 to 12,000 before present, has been nicknamed hobbit for its small size, possibly a result of insular dwarfism.[61] H. floresiensis is intriguing both for its size and its age, being a concrete example of a recent species of the genus Homo that exhibits derived traits not shared with modern humans. In other words, H. floresiensis share a common ancestor with modern humans, but split from the modern human lineage and followed a distinct evolutionary path. The main find was a skeleton believed to be a woman of about 30 years of age. Found in 2003 it has been dated to approximately 18,000 years old. The living woman was estimated to be one meter in height, with a brain volume of just 380 cm3 (considered small for a chimpanzee and less than a third of the H. sapiens average of 1400 cm3).

However, there is an ongoing debate over whether H. floresiensis is indeed a separate species.[62] Some scientists presently believe that H. floresiensis was a modern H. sapiens suffering from pathological dwarfism.[63] This hypothesis is supported in part, because some modern humans who live on Flores, the island where the skeleton was found, are pygmies. This coupled with pathological dwarfism, it is argued, could indeed create a hobbit-like human. The other major attack on H. floresiensis is that it was found with tools only associated with H. sapiens.[63]

The hypothesis of pathological dwarfism, however, fails to explain additional anatomical features that are unlike those of modern humans (diseased or not) but much like those of ancient members of our genus. Aside from cranial features, these features include the form of bones in the wrist, forearm, shoulder, knees, and feet.

Denisova hominin

In 2008, archaeologists working at the site of Denisova Cave in the Altai Mountains of Siberia uncovered a small bone fragment from the fifth finger of a juvenile member of a population now referred to as Denisova hominins.[64] Artifacts, including a bracelet, excavated in the cave at the same level were carbon dated to around 40,000 BP. As DNA had survived in the fossil fragment due to the cool climate of the Denisova Cave, both mtDNA and nuclear genomic DNA has been and sequenced.[65][7]

While the divergence point of the mtDNA was unexpectedly deep in time,[66] the full genomic sequence suggested the Denisovans belonged to the same lineage as Neanderthals, but the two diverged shortly after their line split from that giving rise to modern humans.[7] Modern humans are known to have overlapped with Neanderthals in Europe for more than 10,000 years, and the discovery raises the possibility that Neanderthals, modern humans and the Denisovan hominin may have co-existed. Pääbo noted that the existence of this distant branch creates a much more complex picture of humankind during the Late Pleistocene.[64]

Comparative table of Homo species view · talk · edit
Species Lived when (Ma) Lived where Adult height Adult mass Cranial capacity (cm³) Fossil record Discovery / publication of name
H. antecessor 1.2 – 0.8 Spain 1.75 m (5.7 ft) 90 kg (200 lb) 1,000 2 sites 1997
H. cepranensis 0.9 – 0.8 Italy 1,000 1 skull cap 1994/2003
H. erectus 1.8 – 0.2 Africa, Eurasia (Java, China, India, Caucasus) 1.8 m (5.9 ft) 60 kg (130 lb) 850 (early) – 1,100 (late) Many 1891/1892
H. ergaster 1.9 – 1.4 Eastern and Southern Africa 1.9 m (6.2 ft) 700–850 Many 1975
H. floresiensis 0.10 – 0.012 Indonesia 1.0 m (3.3 ft) 25 kg (55 lb) 400 7 individuals 2003/2004
H. gautengensis >2 – 0.6 South Africa 1.0 m (3.3 ft) 1 individual 2010/2010
H. georgicus 1.8 Georgia 600 4 individuals 1999/2002
H. habilis 2.3 – 1.4 Africa 1.0–1.5 m (3.3–4.9 ft) 33–55 kg (73–120 lb) 510–660 Many 1960/1964
H. heidelbergensis 0.6 – 0.35 Europe, Africa, China 1.8 m (5.9 ft) 60 kg (130 lb) 1,100–1,400 Many 1908
H. neanderthalensis 0.35 – 0.03 Europe, Western Asia 1.6 m (5.2 ft) 55–70 kg (120–150 lb) (heavily built) 1,200–1,900 Many (1829)/1864
H. rhodesiensis 0.3 – 0.12 Zambia 1,300 Very few 1921
H. rudolfensis 1.9 Kenya 1 skull 1972/1986
H. sapiens idaltu 0.16 – 0.15 Ethiopia 1,450 3 craniums 1997/2003
H. sapiens sapiens (modern humans) 0.2 – present Worldwide 1.4–1.9 m (4.6–6.2 ft) 50–100 kg (110–220 lb) 1,000–1,850 Still living —/1758

Use of tools

"A sharp rock", an Oldowan pebble tool, the most basic of human stone tools.
Fire, one of the greatest human discoveries and important in human evolution.
Acheulean hand-axes from Kent. Homo erectus flint work. The types shown are (clockwise from top) cordate, ficron and ovate.
Venus of Willendorf, an example of Paleolithic art

Using tools has been interpreted as a sign of intelligence, and it has been theorized that tool use may have stimulated certain aspects of human evolution—most notably the continued expansion of the human brain. Paleontology has yet to explain the expansion of this organ over millions of years despite being extremely demanding in terms of energy consumption. The brain of a modern human consumes about 20 watts (400 kilocalories per day), which is one fifth of the energy consumption of a human body. Increased tool use would allow hunting for energy-rich meat products, and would enable processing more energy-rich plant products. Researchers have suggested that early hominids were thus under evolutionary pressure to increase their capacity to create and use tools.[67]

Precisely when early humans started to use tools is difficult to determine, because the more primitive these tools are (for example, sharp-edged stones) the more difficult it is to decide whether they are natural objects or human artifacts. There is some evidence that the australopithecines (4 Ma) may have used broken bones as tools, but this is debated.[68]

It should be noted that many species make and use tools, but it is the human species that dominates the areas of making and using more complex tools. The oldest known tools are the "Oldowan stone tools" from Ethiopia. It was discovered that these tools are from 2.5 to 2.6 million years old, which predates the earliest known "Homo" species. There is no known evidence that any "Homo" specimens appeared by 2.5 Ma. A Homo fossil was found near some Oldowan tools, and its age was noted at 2.3 million years old, suggesting that maybe the Homo species did indeed create and use these tools. It is surely possible, but not solid evidence. Bernard Wood noted that "Paranthropus" coexisted with the early Homo species in the area of the "Oldowan Industrial Complex" over roughly the same span of time. Although there is no direct evidence that points to Paranthropus as the tool makers, their anatomy lends to indirect evidence of their capabilities in this area. Most paleoanthropologists agree that the early "Homo" species were indeed responsible for most of the Oldowan tools found. They argue that when most of the Oldowan tools were found in association with human fossils, Homo was always present, but Paranthropus was not.[69]

In 1994, Randall Susman used the anatomy of opposable thumbs as the basis for his argument that both the Homo and Paranthropus species were toolmakers. He compared bones and muscles of human and chimpanzee thumbs, finding that humans have 3 muscles that chimps lack. Humans also have thicker metacarpals with broader heads, making the human hand more successful at precision grasping than the chimpanzee hand. Susman defended that modern anatomy of the human thumb is an evolutionary response to the requirements associated with making and handling tools and that both species were indeed toolmakers.[69]

Stone tools

Stone tools are first attested around 2.6 Ma, when H. habilis in Eastern Africa used so-called pebble tools, choppers made out of round pebbles that had been split by simple strikes.[70] This marks the beginning of the Paleolithic, or Old Stone Age; its end is taken to be the end of the last Ice Age, around 10,000 years ago. The Paleolithic is subdivided into the Lower Paleolithic (Early Stone Age, ending around 350,000–300,000 years ago), the Middle Paleolithic (Middle Stone Age, until 50,000–30,000 years ago), and the Upper Paleolithic.

The period from 700,000–300,000 years ago is also known as the Acheulean, when H. ergaster (or erectus) made large stone hand-axes out of flint and quartzite, at first quite rough (Early Acheulian), later "retouched" by additional, more subtle strikes at the sides of the flakes. After 350,000 BP (Before Present) the more refined so-called Levallois technique was developed. It consisted of a series of consecutive strikes, by which scrapers, slicers ("racloirs"), needles, and flattened needles were made.[70] Finally, after about 50,000 BP, ever more refined and specialized flint tools were made by the Neanderthals and the immigrant Cro-Magnons (knives, blades, skimmers). In this period they also started to make tools out of bone.

Modern humans and the "Great Leap Forward" debate

Until about 50,000–40,000 years ago the use of stone tools seems to have progressed stepwise. Each phase (H. habilis, H. ergaster, H. neanderthalensis) started at a higher level than the previous one, but once that phase started further development was slow. These Homo species were culturally conservative, but after 50,000 BC modern human culture started to change at a much greater speed. Jared Diamond, author of The Third Chimpanzee, and some anthropologists characterize this as a "Great Leap Forward".

Modern humans started burying their dead, making clothing out of hides, developing sophisticated hunting techniques (such as using trapping pits or driving animals off cliffs), and engaging in cave painting.[71] As human culture advanced, different populations of humans introduced novelty to existing technologies: artifacts such as fish hooks, buttons and bone needles show signs of variation among different populations of humans, something that had not been seen in human cultures prior to 50,000 BP. Typically, H. neanderthalensis populations do not vary in their technologies.

Among concrete examples of Modern human behavior, anthropologists include specialization of tools, use of jewellery and images (such as cave drawings), organization of living space, rituals (for example, burials with grave gifts), specialized hunting techniques, exploration of less hospitable geographical areas, and barter trade networks. Debate continues as to whether a "revolution" led to modern humans ("the big bang of human consciousness"), or whether the evolution was more gradual.[72]

Models of human evolution

Today, all humans belong to one population of Homo sapiens sapiens, undivided by species barrier. However, according to the "Out-of-Africa" model this is not the first species of hominids: the first species of genus Homo, Homo habilis, evolved in East Africa at least 2 Ma, and members of this species populated different parts of Africa in a relatively short time. Homo erectus evolved more than 1.8 Ma, and by 1.5 Ma had spread throughout the Old World.

Anthropologists have been divided as to whether current human population evolved only in East Africa, speciated, then migrated out of Africa and replaced human populations in Eurasia (called the "Out-of-Africa" Model or the "Complete-Replacement" Model) or evolved as one interconnected population (as postulated by the Multiregional Evolution hypothesis).

Out of Africa

Divergence of mitochondrial DNA, passed on only through mothers.[73]

According to the Out-of-Africa model, developed by Chris Stringer and Peter Andrews, modern H. sapiens evolved in Africa 200,000 years ago. Homo sapiens began migrating from Africa between 70,000 – 50,000 years ago and eventually replaced existing hominid species in Europe and Asia.[74][75] Out of Africa has gained support from research using female mitochondrial DNA (mtDNA) and the male Y chromosome. After analysing genealogy trees constructed using 133 types of mtDNA, researchers concluded that all were descended from a woman from Africa, dubbed Mitochondrial Eve. Out of Africa is also supported by the fact that mitochondrial genetic diversity is highest among African populations.[76]

There are differing theories on whether there was a single exodus or several. A multiple dispersal model involves the Southern Dispersal theory,[77] which has gained support in recent years from genetic, linguistic and archaeological evidence. In this theory, there was a coastal dispersal of modern humans from the Horn of Africa around 70,000 years ago. This group helped to populate Southeast Asia and Oceania, explaining the discovery of early human sites in these areas much earlier than those in the Levant. A second wave of humans dispersed across the Sinai peninsula into Asia, resulting in the bulk of human population for Eurasia. This second group possessed a more sophisticated tool technology and was less dependent on coastal food sources than the original group. Much of the evidence for the first group's expansion would have been destroyed by the rising sea levels at the end of each glacial maximum.[77] The multiple dispersal model is contradicted by studies indicating that the populations of Eurasia and the populations of Southeast Asia and Oceania are all descended from the same mitochondrial DNA lineages, which support a single migration out of Africa that gave rise to all non-African populations.[78]

The broad study of African genetic diversity headed by Sarah Tishkoff found the San people to express the greatest genetic diversity among the 113 distinct populations sampled, making them one of 14 "ancestral population clusters". The research also located the origin of modern human migration in south-western Africa, near the coastal border of Namibia and Angola.[79]

According to the Toba catastrophe theory to which some anthropologists and archeologists subscribe, the supereruption of Lake Toba on Sumatra island in Indonesia roughly 70,000 years ago had global consequences,[80] killing most humans then alive and creating a population bottleneck that affected the genetic inheritance of all humans today.[81]

Multiregional model

Multiregional evolution, a model to account for the pattern of human evolution, was proposed by Milford H. Wolpoff[82] in 1988.[83] Multiregional evolution holds that human evolution from the beginning of the Pleistocene 2.5 million years BP to the present day has been within a single, continuous human species, evolving worldwide from Homo erectus into modern Homo sapiens. According to the multiregional hypothesis, fossil and genomic data are evidence for worldwide human evolution and contradict the recent speciation postulated by the Recent African origin hypothesis. The fossil evidence was insufficient for Richard Leakey to resolve this debate.[84] Studies of haplogroups in Y-chromosomal DNA and mitochondrial DNA have largely supported a recent African origin.[85] Evidence from autosomal DNA also predominantly supports a Recent African origin. However evidence for archaic admixture in modern humans had been suggested by some studies.[86] Recent sequencing of Neanderthal [87] and Denisovan[88] genomes show that some admixture occurred. Modern humans outside Africa have 2-4% Neanderthal alleles in their genome, and some Melanesians have an additional 4-6% of Denisovan alleles. These new results do not contradict the « Out of Africa » model, except in its strictest interpretation. After recovery from a genetic bottleneck that might be due to the Toba supervolcano catastrophe (73.000 years ago), a fairly small group left Africa and briefly interbred with Neanderthals, probably in the middle-east or even North Africa before their departure. Their still predominantly-African descendants spread to populate the world. A fraction in turn interbred with Denisovans, probably in south-east Asia, before populating Melanesia.[89] HLA haplotypes of Neanderthal and Denisova origin have been identified in modern Eurasian and Oceanian populations.[9]

Recent and current human evolution

Natural selection occurs in modern human populations. For example, the population which is at risk of the severe debilitating disease kuru has significant over-representation of an immune variant of the prion protein gene G127V versus non-immune alleles. The frequency of this genetic variant is due to the survival of immune persons.[90][91] Other reported evolutionary trends in other populations include a lengthening of the reproductive period, reduction in cholesterol levels, blood glucose and blood pressure.[92]

It has been argued that human evolution has accelerated since, and as a result of, the development of agriculture and civilization some 10,000 years ago. It is claimed that this has resulted in substantial genetic differences between different current human populations.[93]

Genetics

Human evolutionary genetics studies how one human genome differs from the other, the evolutionary past that gave rise to it, and its current effects. Differences between genomes have anthropological, medical and forensic implications and applications. Genetic data can provide important insight into human evolution.

Notable human evolution researchers

  • Robert Broom, a Scottish physician and palaeontologist whose work on South Africa led to the discovery and description of the Paranthropus genus of hominins, and of "Mrs. Ples"
  • Raymond Dart, an Australian anatomist and palaeoanthropologist, whose work at Taung, in South Africa, led to the discovery of Australopithecus africanus
  • Charles Darwin, a British naturalist who documented considerable evidence that species originate through evolutionary change
  • Henry McHenry, an American anthropologist who specializes in studies of human evolution, the origins of bipedality, and paleoanthropology
  • Donald Johanson, credited with the discovery of Australopithecus afarensis
  • Jeffrey Laitman, an American anatomist and physical anthropologist whose work has explored the evolution of the vocal tract and speech
  • Louis Leakey, an African archaeologist and naturalist whose work was important in establishing human evolutionary development in Africa
  • Mary Leakey, a British archaeologist and anthropologist whose discoveries in Africa include the Laetoli footprints
  • Richard Leakey, an African paleontologist and archaeologist, son of Louis and Mary Leakey
  • Svante Pääbo, a Swedish biologist specializing in evolutionary genetics
  • David Pilbeam, a paleoanthropologist, researcher and writer on a range of topics involving human and primate evolution.
  • Jeffrey H. Schwartz, an American physical anthropologist and professor of biological anthropology
  • Chris Stringer, anthropologist, leading proponent of the recent single origin hypothesis
  • Alan Templeton, geneticist and statistician, proponent of the multiregional hypothesis
  • Philip V. Tobias, a South African palaeoanthropologist is one of the world's leading authorities on the evolution of humankind
  • Erik Trinkaus, a prominent American paleoanthropologist and expert on Neanderthal biology and human evolution
  • Milford H. Wolpoff, an American paleoanthropologist who is the leading proponent of the multiregional evolution hypothesis.

Species list

This list is in chronological order across the page by genus.

See also

References

Notes

  1. ^ Heng HH (May 2009). "The genome-centric concept: resynthesis of evolutionary theory". Bioessays 31 (5): 512–25. doi:10.1002/bies.200800182. PMID 19334004. 
  2. ^ Stringer, C.B. (1994). "Evolution of early humans". In Steve Jones, Robert Martin & David Pilbeam (eds.). The Cambridge Encyclopedia of Human Evolution. Cambridge: Cambridge University Press. p. 242. ISBN 978-0-521-32370-3.  Also ISBN 978-0-521-46786-5 (paperback)
  3. ^ McHenry, H.M (2009). "Human Evolution". In Michael Ruse & Joseph Travis. Evolution: The First Four Billion Years. Cambridge, Massachusetts: The Belknap Press of Harvard University Press. p. 265. ISBN 978-0-674-03175-3. 
  4. ^ "Out of Africa Revisited - 308 (5724): 921g - Science". Sciencemag.org. 2005-05-13. doi:10.1126/science.308.5724.921g. Archived from the original on 2010-11-22. http://www.sciencemag.org/cgi/content/summary/sci;308/5724/921g. Retrieved 2009-11-23. 
  5. ^ Nature (2003-06-12). "Access : Human evolution: Out of Ethiopia". Nature. Archived from the original on 2010-11-22. http://www.nature.com/nature/journal/v423/n6941/full/423692a.html. Retrieved 2009-11-23. 
  6. ^ "Origins of Modern Humans: Multiregional or Out of Africa?". ActionBioscience. Archived from the original on 2010-11-22. http://www.actionbioscience.org/evolution/johanson.html. Retrieved 2009-11-23. 
  7. ^ a b c Reich D, Green RE, Kircher M, et al. (December 2010). "Genetic history of an archaic hominin group from Denisova Cave in Siberia". Nature 468 (7327): 1053–60. doi:10.1038/nature09710. PMID 21179161. 
  8. ^ Noonan JP (May 2010). "Neanderthal genomics and the evolution of modern humans". Genome Res. 20 (5): 547–53. doi:10.1101/gr.076000.108. PMC 2860157. PMID 20439435. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2860157. 
  9. ^ a b Laurent Abi-Rached, et. al. (2011-08-25). "The Shaping of Modern Human Immune Systems by Multiregional Admixture with Archaic Humans". Science 334 (6052). doi:10.1126/science.1209202. Archived from the original on Aug 2011. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1122&context=publichealthresources. 
  10. ^ American Heritage Dictionary; Houghton Mifflin Company (October 2006). More word histories and mysteries: from aardvark to zombie. Houghton Mifflin Harcourt. pp. 99–. ISBN 978-0-618-71681-4. http://books.google.com/books?id=UbXao0TjfKgC&pg=PA99. Retrieved 10 November 2011. 
  11. ^ Darwin, Charles (1871. This edition published 1981, with Introduction by John Tyler Bonner & Robert M. May). The Descent of Man, and Selection in Relation to Sex. Princeton, New Jersey: Princeton University Press. ISBN 0-691-02369-7.. 
  12. ^ Walter Carl Hartwig (2002). The primate fossil record. Cambridge University Press. p. 409. ISBN 978-0-521-66315-1. http://books.google.com/books?id=Ezm1OA_s6isC&pg=PA409. Retrieved 6 November 2011. 
  13. ^ Frederick Grine (31 December 2007). Evolutionary History of the "Robust" Australopithecines. Transaction Publishers. p. 301. ISBN 978-0-202-36137-6. http://books.google.com/books?id=AmQ46CDN6DsC&pg=PA301. Retrieved 6 November 2011. 
  14. ^ a b Richard Dawkins; Yan Wong (September 2005). The Ancestor's Tale: A Pilgrimage to the Dawn of Evolution. Houghton Mifflin Harcourt. p. 86. ISBN 978-0-618-61916-0. http://books.google.com/books?id=rR9XPnaqvCMC&pg=PA86. Retrieved 6 November 2011. 
  15. ^ a b Philip Briggs (1 October 2009). Tanzania: With Zanzibar, Pemba & Mafia. Bradt Travel Guides. p. 6. ISBN 978-1-84162-288-0. http://books.google.com/books?id=uvAFRd1CtHMC&pg=PA6. Retrieved 6 November 2011. 
  16. ^ Amade M'charek (2005). The Human Genome Diversity Project: an ethnography of scientific practice. Cambridge University Press. p. 96. ISBN 978-0-521-83222-9. http://books.google.com/books?id=n-K436zeUY8C&pg=PA96. Retrieved 10 November 2011. 
  17. ^ Rob DeSalle; Ian Tattersall (2008). Human origins: what bones and genomes tell us about ourselves. Texas A&M University Press. p. 146. ISBN 978-1-58544-567-7. http://books.google.com/books?id=Bf4Sitw7YaIC&pg=PA146. Retrieved 10 November 2011. 
  18. ^ R. J. Trent (2005). Molecular medicine: an introductory text. Academic Press. pp. 6–. ISBN 978-0-12-699057-7. http://books.google.com/books?id=772BEp8ZyMYC&pg=PA6. Retrieved 9 November 2011. 
  19. ^ Donovan Webster; Spencer Wells (20 April 2010). Meeting the Family: One Man's Journey Through His Human Ancestry. National Geographic Books. p. 53. ISBN 978-1-4262-0573-6. http://books.google.com/books?id=cdiy1EhJVW0C&pg=PA53. Retrieved 10 November 2011. 
  20. ^ Michael R. Speicher; Stylianos E. Antonarakis; Arno G. Motulsky (3 February 2010). Vogel and Motulsky's Human Genetics: Problems and Approaches. Springer. p. 606. ISBN 978-3-540-37653-8. http://books.google.com/books?id=FlfPSpBvKLgC&pg=PA606. Retrieved 10 November 2011. 
  21. ^ Dr Kutty (14 September 2009). Adam's Gene and the Mitochondrial Eve. Xlibris Corporation. p. 40. ISBN 978-1-4415-0729-7. http://books.google.com/books?id=sUqYgipyiGMC&pg=PA40. Retrieved 9 November 2011. 
  22. ^ Kordos L, Begun DR (2001). "Primates from Rudabánya: allocation of specimens to individuals, sex and age categories". J. Hum. Evol. 40 (1): 17–39. doi:10.1006/jhev.2000.0437. PMID 11139358. 
  23. ^ David W. Cameron (2004). Hominid adaptations and extinctions. UNSW Press. p. 76. ISBN 978-0-86840-716-6. http://books.google.com/books?id=fnqzb4_UVfkC&pg=PA76. Retrieved 6 November 2011. 
  24. ^ David Rains Wallace (13 September 2005). Beasts of Eden: Walking Whales, Dawn Horses, and Other Enigmas of Mammal Evolution. University of California Press. pp. 240–. ISBN 978-0-520-24684-3. http://books.google.com/books?id=YoyQQEOKGVQC&pg=PA240. Retrieved 6 November 2011. 
  25. ^ Zalmout, I.S.; Sanders, W.J.; MacLatchy, L.M.; Gunnell, G.F.; Al-Mufarreh, Y.A.; Ali, M.A.; Nasser, A.-A.H.; Al-Masari, A.M. et al. (2010). "New Oligocene primate from Saudi Arabia and the divergence of apes and Old World Monkeys". Nature 466 (7304): 360–364. doi:10.1038/nature09094. PMID 20631798. 
  26. ^ Srivastava (2009). Morphology Of The Primates And Human Evolution. PHI Learning Pvt. Ltd.. p. 87. ISBN 978-81-203-3656-8. http://books.google.com/books?id=kCerOsM8XMwC&pg=PA87. Retrieved 6 November 2011. 
  27. ^ Strait DS, Grine FE, Moniz MA (1997). "A reappraisal of early hominid phylogeny". J. Hum. Evol. 32 (1): 17–82. doi:10.1006/jhev.1996.0097. PMID 9034954. 
  28. ^ a b Bill Bryson (2004). "28. The Mysterious Biped". A Short History of Nearly Everything. Random House, Inc.. pp. 522–543. ISBN 978-0-385-66004-4. http://books.google.com/books?id=RKHLD9qNs64C. 
  29. ^ Walker, Alan (2006). "Early Hominin Diets: Overview and Historical Perspectives". In Peter Ungar. Evolution of the Human Diet: The Known, the Unknown, and the Unknowable. US: Oxford University Press. pp. 3–10. ISBN 978-0-19-518346-7. http://books.google.com/?id=6mxZ1hNBHgkC&pg=PA357&lpg=PA357&dq=%22The+Calcaneus+of+Australopithecus+afarensis+and+its+implications+for+the+Evolution+of+Bipedality%22&q=%22The%20Calcaneus%20of%20Australopithecus%20afarensis%20and%20its%20implications%20for%20the%20Evolution%20of%20Bipedality%22.  (scroll up to view chapter 1 & part of chapter 2, which is a serendipitous result from another search. Subsequent attempts get a targeted search result gave returns without chapter 1).
  30. ^ Peter Ungar & Teaford, Mark F. (2002). Human Diet: Its Origin and Evolution. Westport, CT: Bergin & Garvey. p. 206. ISBN 978-0-89789-736-5. 
  31. ^ Bogin, Barry (1997). "The evolution of human nutrition". In Romanucci-Ross, Lola; Moerman, Daniel E.; & Tancredi, Laurence R.. The Anthropology of Medicine: From Culture to Method (3 ed.). South Hadley, Mass.: Bergen and Garvey. pp. 96–142. ISBN 978-0-89789-516-3. http://web.archive.org/web/20031203003838/http://citd.scar.utoronto.ca/ANTAO1/Projects/Bogin.html. 
  32. ^ Barnicot NA (2005, April/June). "Human nutrition: evolutionary perspectives". Integr Physiol Behav Sci 40 (2): 114–17. doi:10.1007/BF02734246. PMID 17393680. 
  33. ^ Leonard WR, Snodgrass JJ, Robertson ML (2007). "Effects of brain evolution on human nutrition and metabolism". Annu Rev Nutr. 27: 311–27. 
  34. ^ Wood, B. & Collard, M. (1999) The changing face of Genus Homo. Evol. Anth. 8(6) 195-207
  35. ^ "Toothy Tree-Swinger May Be Earliest Human". News.discovery.com. 2010-05-21. http://news.discovery.com/human/human-ancestor-tree-swinger.html. Retrieved 2011-05-14. 
  36. ^ Wood B (1999). "'Homo rudolfensis' Alexeev, 1986-fact or phantom?". J. Hum. Evol. 36 (1): 115–8. doi:10.1006/jhev.1998.0246. PMID 9924136. 
  37. ^ Gabounia L. de Lumley M. Vekua A. Lordkipanidze D. de Lumley H. (2002). "Discovery of a new hominid at Dmanisi (Transcaucasia, Georgia)". Comptes Rendus Palevol, 1 (4): 243–53. doi:10.1016/S1631-0683(02)00032-5. 
  38. ^ Lordkipanidze D, Vekua A, Ferring R, et al. (2006). "A fourth hominin skull from Dmanisi, Georgia". The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology 288 (11): 1146–57. doi:10.1002/ar.a.20379. PMID 17031841. 
  39. ^ Figure 1. Phylogeny of Primate Lice from Morphological and Molecular Data, in Reed DL, Smith VS, Hammond SL, Rogers AR, Clayton DH PLoS (2004). "Genetic Analysis of Lice Supports Direct Contact between Modern and Archaic Humans". PLoS Biol 2 (11): e340. doi:10.1371/journal.pbio.0020340. PMC 521174. PMID 15502871. Archived from the original on 2010-11-22. http://biology.plosjournals.org/perlserv/?request=slideshow&type=figure&doi=10.1371/journal.pbio.0020340&id=15540. 
  40. ^ Turner W (1895). "On M. Dubois' Description of Remains recently found in Java, named by him Pithecanthropus erectus: With Remarks on so-called Transitional Forms between Apes and Man". Journal of anatomy and physiology 29 (Pt 3): 424–45. PMC 1328414. PMID 17232143. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1328414. 
  41. ^ Spoor F, Wood B, Zonneveld F (1994). "Implications of early hominid labyrinthine morphology for evolution of human bipedal locomotion". Nature 369 (6482): 645–8. doi:10.1038/369645a0. PMID 8208290. 
  42. ^ Bermúdez de Castro JM, Arsuaga JL, Carbonell E, Rosas A, Martínez I, Mosquera M (1997). "A hominid from the lower Pleistocene of Atapuerca, Spain: possible ancestor to Neandertals and modern humans". Science 276 (5317): 1392–5. doi:10.1126/science.276.5317.1392. PMID 9162001. 
  43. ^ Carbonell, Eudald; José M. Bermúdez de Castro et al. (2008-03-27). "The first hominin of Europe". Nature 452 (7186): 465–469. doi:10.1038/nature06815. PMID 18368116. Archived from the original on 2010-11-22. http://www.nature.com/nature/journal/v452/n7186/full/nature06815.html. Retrieved 2008-03-26. 
  44. ^ Manzi G, Mallegni F, Ascenzi A (2001). "A cranium for the earliest Europeans: Phylogenetic position of the hominid from Ceprano, Italy". Proc. Natl. Acad. Sci. U.S.A. 98 (17): 10011–6. doi:10.1073/pnas.151259998. PMC 55569. PMID 11504953. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=55569. 
  45. ^ Czarnetzki, A; Jakob, T; Pusch, CM (2003). "Palaeopathological and variant conditions of the Homo heidelbergensis type specimen (Mauer, Germany)". Journal of Human Evolution 44 (4): 479–95. doi:10.1016/S0047-2484(03)00029-0. PMID 12727464. 
  46. ^ "Scientists discover hominid cranium in Ethiopia" (Press release). Indiana University. March 27, 2006. http://newsinfo.iu.edu/news/page/normal/3142.html. Retrieved 2006-11-26. 
  47. ^ Herrera, K. J.; Somarelli, J. A.; Lowery, R. K.; Herrera, R. J. (2009). "To what extent did Neanderthals and modern humans interact?". Biological Reviews 84 (2): 245–257. doi:10.1111/j.1469-185X.2008.00071.x. PMID 19391204.  edit
  48. ^ Harvati K (2003). "The Neanderthal taxonomic position: models of intra- and inter-specific craniofacial variation". J. Hum. Evol. 44 (1): 107–32. doi:10.1016/S0047-2484(02)00208-7. PMID 12604307. 
  49. ^ Krings M, Stone A, Schmitz RW, Krainitzki H, Stoneking M, Pääbo S (1997). "Neandertal DNA sequences and the origin of modern humans". Cell 90 (1): 19–30. doi:10.1016/S0092-8674(00)80310-4. PMID 9230299. 
  50. ^ Green RE, et al. (2008). "A complete Neandertal mitochondrial genome sequence determined by high-throughput sequencing". Cell 134 (3): 416–426. doi:10.1016/j.cell.2008.06.021. PMC 2602844. PMID 18692465. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2602844. 
  51. ^ Serre D, Langaney A, Chech M, et al. (2004). "No Evidence of Neandertal mtDNA Contribution to Early Modern Humans". PLoS Biol. 2 (3): E57. doi:10.1371/journal.pbio.0020057. PMC 368159. PMID 15024415. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=368159. 
  52. ^ a b Jennifer Viegas (2010-05-06). "Neanderthals, humans interbred, DNA proves". Discovery News. Archived from the original on 2010-11-22. http://news.discovery.com/human/neanderthal-human-interbreed-dna.html. Retrieved 2010-08-17. 
  53. ^ Gutiérrez G, Sánchez D, Marín A (2002). "A reanalysis of the ancient mitochondrial DNA sequences recovered from Neandertal bones". Mol. Biol. Evol. 19 (8): 1359–66. PMID 12140248. 
  54. ^ Hebsgaard MB, Wiuf C, Gilbert MT, Glenner H, Willerslev E (2007). "Evaluating Neanderthal genetics and phylogeny". J. Mol. Evol. 64 (1): 50–60. doi:10.1007/s00239-006-0017-y. PMID 17146600. 
  55. ^ Diamond, Jared (1992). The Third Chimpanzee: The Evolution and Future of the Human Animal. Harper Perennial. ISBN 978-0-06-098403-8. 
  56. ^ How Neanderthals met a grisly fate: devoured by humans. The Observer. May 17, 2009.
  57. ^ "DNA identifies new ancient human dubbed 'X-woman'". BBC News. March 25, 2010.
  58. ^ Supervolcanoes, BBC2, 3 February 2000
  59. ^ Stanley H. Ambrose (1998). "Late Pleistocene human population bottlenecks, volcanic winter, and differentiation of modern humans". Journal of Human Evolution 34 (6): 623–651. doi:10.1006/jhev.1998.0219. PMID 9650103. 
  60. ^ Ambrose, Stanley H. (2005). "Volcanic Winter, and Differentiation of Modern Humans". Bradshaw Foundation. http://www.bradshawfoundation.com/evolution/. Retrieved 2006-04-08. 
  61. ^ Brown P, Sutikna T, Morwood MJ, et al. (2004). "A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia". Nature 431 (7012): 1055–61. doi:10.1038/nature02999. PMID 15514638. 
  62. ^ Argue D, Donlon D, Groves C, Wright R (2006). "Homo floresiensis: microcephalic, pygmoid, Australopithecus, or Homo?". J. Hum. Evol. 51 (4): 360–74. doi:10.1016/j.jhevol.2006.04.013. PMID 16919706. 
  63. ^ a b Martin RD, Maclarnon AM, Phillips JL, Dobyns WB (2006). "Flores hominid: new species or microcephalic dwarf?". The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology 288 (11): 1123–45. doi:10.1002/ar.a.20389. PMID 17031806. 
  64. ^ a b Sample, Ian (March 24, 2010). "New species of human ancestor found in Siberia". The Guardian. Archived from the original on 2010-11-22. http://www.guardian.co.uk/science/2010/mar/24/new-human-species-siberia 
  65. ^ Krause, Johannes; Fu, Qiaomei; Good, Jeffrey M.; Viola, Bence; Shunkov, Michael V.; Derevianko, Anatoli P. & Pääbo, Svante (2010). "The complete mitochondrial DNA genome of an unknown hominin from southern Siberia". Nature 464 (7290): 894–897. doi:10.1038/nature08976. PMID 20336068 
  66. ^ Katsnelson, Alla (March 24, 2010). "New hominin found via mtDNA". The Scientist. Archived from the original on 2010-11-22. http://www.the-scientist.com/blog/display/57254/#ixzz0j820ioz1 
  67. ^ Gibbons, Ann (1998). "Solving the Brain's Energy Crisis". Science 280 (5368): 1345–47. doi:10.1126/science.280.5368.1345. PMID 9634409. 
  68. ^ F. Howell; François Bourlière (30 November 2007). African Ecology and Human Evolution. Transaction Publishers. p. 398. ISBN 978-0-202-36136-9. http://books.google.com/books?id=-kOvkb-xbU8C&pg=PA398. Retrieved 6 November 2011. 
  69. ^ a b Freeman, Scott; Jon C. Herron. Evolutionary Analysis (4th ed.)., Pearson Education, Inc. (2007). ISBN 978-0-13-227584-2 pages 786-788
  70. ^ a b Plummer T (2004). "Flaked stones and old bones: Biological and cultural evolution at the dawn of technology". Am. J. Phys. Anthropol. Suppl 39: 118–64. doi:10.1002/ajpa.20157. PMID 15605391. 
  71. ^ Ambrose SH (2001). "Paleolithic technology and human evolution". Science 291 (5509): 1748–53. doi:10.1126/science.1059487. PMID 11249821. 
  72. ^ Mcbrearty S, Brooks AS (2000). "The revolution that wasn't: a new interpretation of the origin of modern human behavior". J. Hum. Evol. 39 (5): 453–563. doi:10.1006/jhev.2000.0435. PMID 11102266. 
  73. ^ Behar et al. 2008, Gonder et al. 2007, Reed and Tishkoff.
  74. ^ "Modern Humans Came Out of Africa, "Definitive" Study Says". News.nationalgeographic.com. 2010-10-28. http://news.nationalgeographic.com/news/2007/07/070718-african-origin.html. Retrieved 2011-05-14. 
  75. ^ Stringer CB, Andrews P (March 1988). "Genetic and fossil evidence for the origin of modern humans". Science 239 (4845): 1263–8. doi:10.1126/science.3125610. PMID 3125610. 
  76. ^ Cann RL, Stoneking M, Wilson AC (1987). "Mitochondrial DNA and human evolution". Nature 325 (6099): 31–6. doi:10.1038/325031a0. PMID 3025745. Archived from the original on 2010-11-22. http://artsci.wustl.edu/~landc/html/cann/. 
  77. ^ a b Searching for traces of the Southern Dispersal, by Dr. Marta Mirazón Lahr, et al.
  78. ^ Macaulay, V.; Hill, C; Achilli, A; Rengo, C; Clarke, D; Meehan, W; Blackburn, J; Semino, O et al. (2005). "Single, Rapid Coastal Settlement of Asia Revealed by Analysis of Complete Mitochondrial Genomes". Science 308 (5724): 1034–6. doi:10.1126/science.1109792. PMID 15890885. http://www.sciencemag.org/cgi/content/abstract/308/5724/1034. 
  79. ^ Gill, Victoria (May 1, 2009). "Africa's genetic secrets unlocked". BBC News. http://news.bbc.co.uk/2/hi/science/nature/8027269.stm. Retrieved June 8, 2011.  the results were published in the online edition of the journal Science.
  80. ^ "The new batch - 150,000 years ago". BBC - Science & Nature - The evolution of man.
  81. ^ "When humans faced extinction". BBC. 2003-06-09. Archived from the original on 2010-11-22. http://news.bbc.co.uk/2/hi/science/nature/2975862.stm. Retrieved 2007-01-05. 
  82. ^ Wolpoff, MH; Hawks J, Caspari R (2000). "Multiregional, not multiple origins". Am J Phys Anthropol 112 (1): 129–36. doi:10.1002/(SICI)1096-8644(200005)112:1<129::AID-AJPA11>3.0.CO;2-K. PMID 10766948. http://www3.interscience.wiley.com/journal/71008905/abstract. 
  83. ^ Wolpoff, MH; JN Spuhler, FH Smith, J Radovcic, G Pope, DW Frayer, R Eckhardt, and G Clark (1988). "Modern Human Origins". Science 241 (4867): 772–4. doi:10.1126/science.3136545. PMID 3136545. http://www.sciencemag.org/cgi/pdf_extract/241/4867/772. 
  84. ^ Leakey, Richard (1994). The Origin of Humankind. Science Masters Series. New York, NY: Basic Books. pp. 87–89. ISBN 978-0-465-05313-1. 
  85. ^ Jorde LB, Bamshad M, Rogers AR (February 1998). "Using mitochondrial and nuclear DNA markers to reconstruct human evolution". Bioessays 20 (2): 126–36. doi:10.1002/(SICI)1521-1878(199802)20:2<126::AID-BIES5>3.0.CO;2-R. PMID 9631658. 
  86. ^ Wall, J. D.; Lohmueller, K. E.; Plagnol, V. (2009). "Detecting Ancient Admixture and Estimating Demographic Parameters in Multiple Human Populations". Molecular Biology and Evolution 26 (8): 1823–7. doi:10.1093/molbev/msp096. PMC 2734152. PMID 19420049. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2734152. 
  87. ^ Green RE, Krause J, et al. A draft sequence of the Neandertal genome. Science. 2010 May 7;328(5979):710-22. PMID: 20448178
  88. ^ ^ Reich D, Green RE, Kircher M, et al. (December 2010). "Genetic history of an archaic hominin group from Denisova Cave in Siberia". Nature 468 (7327): 1053–60. doi:10.1038/nature09710. PMID 21179161.
  89. ^ Reich D ., et al. Denisova admixture and the first modern human dispersals into southeast Asia and oceania. Am J Hum Genet. 2011 Oct 7;89(4):516-28, PMID: 21944045 .
  90. ^ Medical Research Council (UK) ((November 21, 2009)). "Brain Disease 'Resistance Gene' evolves in Papua New Guinea community; could offer insights Into CJD". Science Daily (online) (Science News). Archived from the original on 2010-11-22. http://www.sciencedaily.com/releases/2009/11/091120091959.htm. Retrieved 2009-11-22. 
  91. ^ Mead, S.; Whitfield, J.; Poulter, M.; Shah, P.; Uphill, J.; Campbell, T.; Al-Dujaily, H.; Hummerich, H. et al. (2009). "A Novel Protective Prion Protein Variant that Colocalizes with Kuru Exposure.". The New England journal of medicine 361 (21): 2056–2065. doi:10.1056/NEJMoa0809716. PMID 19923577.  edit
  92. ^ Byars, S. G.; Ewbank, D.; Govindaraju, D. R.; Stearns, S. C. (2009). "Evolution in Health and Medicine Sackler Colloquium: Natural selection in a contemporary human population". Proceedings of the National Academy of Sciences 107: 1787. Bibcode 2010PNAS..107.1787B. doi:10.1073/pnas.0906199106. PMC 2868295. PMID 19858476. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2868295.  edit
  93. ^ Cochran G & Harpending H. 2009. The 10,000 Year Explosion. Basic Books N.Y.

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