Homo neanderthalensis, Photo: Michael Lahanas Cladus: Eukaryota Name Homo neanderthalensis King, 1864. Vernacular names
The first proto-Neanderthal traits appeared in Europe as early as 600,000–350,000 years ago.[2] Proto-Neanderthal traits are occasionally grouped with another phenetic 'species', Homo heidelbergensis, or a migrant form, Homo rhodesiensis. By 130,000 years ago, complete Neanderthal characteristics had appeared. These characteristics then disappeared in Asia by 50,000 years ago and in Europe by about 30,000 years ago, with no further individuals having enough Neanderthal morphological traits to be considered as part of Homo neanderthalensis.[3][not in citation given] Genetic evidence suggests interbreeding took place with Homo sapiens (anatomically modern humans) between roughly 80,000 and 50,000 years ago in the Middle East, resulting in 1–4% of the genome of people from Eurasia having been contributed by Neanderthals.[4][5] The youngest Neanderthal finds include Hyaena Den (UK), considered older than 30,000 years ago, while the Vindija (Croatia) Neanderthals have been re-dated to between 33,000 and 32,000 years ago. No definite specimens younger than 30,000 years ago have been found; however, evidence of fire by Neanderthals at Gibraltar indicate they may have survived there until 24,000 years ago. Cro-Magnon or early modern human skeletal remains with 'Neanderthal traits' were found in Lagar Velho (Portugal), dated to 24,500 years ago and controversially interpreted as indications of extensively admixed populations.[6] Neanderthal stone tools provide further evidence for their presence where skeletal remains have not been found. The last traces of Mousterian culture, a type of stone tools associated with Neanderthals, were found in Gorham's Cave on the remote south-facing coast of Gibraltar.[7] Other tool cultures sometimes associated with Neanderthal include Châtelperronian, Aurignacian, and Gravettian, with the latter extending to 22,000 years ago, the last indication of Neanderthal presence. Neanderthal cranial capacity is thought to have been as large as that of a Homo sapiens, perhaps larger, indicating their brain size may have been comparable as well. In 2008, a group of scientists created a study using three-dimensional computer-assisted reconstructions of Neanderthal infants based on fossils found in Russia and Syria, showing that they had brains as large as modern humans' at birth and larger than modern humans' as adults.[8] Neanderthal males stood about 164–168 cm (65–66 in), and were heavily built with robust bone structure. They were much stronger than Homo sapiens, having particularly strong arms and hands.[9] Females stood about 152–156 cm (60–61 in) tall.[10] In 2010 a U.S. researcher reported finding cooked plant matter in the teeth of a Neanderthal skull, contradicting the earlier belief they were exclusively (or almost exclusively) carnivorous[11] and apex predators.[12][not in citation given][13]
The species is named after the Neander valley, located about 12 km (7.5 mi) east of Düsseldorf, Germany. This ravine formed by the river Düssel, widened out by mining, was named Neanderthal in the early 19th century to honour the clergyman and hymn writer Joachim Neander: "Tal" (spelled "Thal" until the German spelling reform of 1901) is the German word for valley.[14] The fossil discovered in the Feldhofer Cave in the limestone cliffs of the Neanderthal in 1856,[14] Neanderthal 1, was known as the "Neanderthal skull" or "Neanderthal cranium" in anthropological literature, and the individual reconstructed on the basis of the skull was occasionally called the "Neanderthal man".[15] The binomial name Homo neanderthalensis, extending the name "Neanderthal man" from the individual type specimen to the entire species, was proposed by the Anglo-Irish geologist William King in 1864. This had priority over the proposal put forward in 1866 by Ernst Haeckel, Homo stupidus.[14] The practice of referring to the members of the species simply as "the Neanderthals", singular "a Neanderthal", emerges in popular literature of the 1920s.[16] The spelling of the German word Thal ("dale, valley"), was changed to Tal in 1901, and the spelling of the valley was also changed accordingly to Neandertal. The former spelling is, however, often retained in English for the hominid. The spelling with th is in addition always used in scientific names throughout the world. In German, however, the modern spelling with t is used in referring to both the hominid and the valley. Neandertal is a widespread alternative spelling in English. The pronunciation of the German name Neandert(h)aler (regardless of spelling) is [neˈandɐˌtʰaːlɐ]. American English speakers commonly pronounce it as /θ/ (th as in thin), but American scientists usually use /t/[citation needed]. British English speakers usually pronounce it as /t/ followed by a long a as in tar,[17] matching the German pronunciation. The pronunciation /niːˈændərθɔːl/ is very common in the United States and is often listed first in US dictionaries, for example American Heritage Dictionary and Random House Dictionaries.[18] The UK pronunciation is /niːˈændərtɑːl/, as shown in Cambridge Advanced Learner's Dictionary,[19] and Oxford Advanced Learner's Dictionary.[20] Classification For some time, scientists have debated whether Neanderthals should be classified as Homo neanderthalensis or "Homo sapiens neanderthalensis", the latter placing Neanderthals as a subspecies of Homo sapiens.[not in citation given][21] Some morphological studies support the view that Homo neanderthalensis is a separate species and not a subspecies.[22] Others, for example University of Cambridge Professor Paul Mellars, say "no evidence has been found of cultural interaction"[23] and evidence from mitochondrial DNA studies have been interpreted as evidence Neanderthals were not a subspecies of H. sapiens,[24] though more recent genomic evidence showed otherwise.[4][5] And as a result of strong evidence of interbreeding between the two races in order to give fertile offspring, some scientists are being inclined more and more to classify the Neanderthal as a subspecies of H. sapiens,[1][4][5] as by definition in biology, two different species can not produce fertile offspring. Neanderthals evolved from early Homo along a path similar to Homo sapiens, both deriving from a chimp-like ancestor between five and 10 million years ago. Like H. sapiens, Neanderthals are related to Australopithecus, Homo habilis, and Homo ergaster; the exact descent remains uncertain. The last common ancestor between anatomically modern Homo sapiens and Neanderthals appears to be Homo rhodesiensis, named after an archaic Homo sapiens fossil, Broken hill 1 (Kabwe 1) discovered in the territory of Rhodesia in 1921. Homo rhodesiensis arose in Africa an estimated 0.7 to 1 million years ago. The earliest estimates for Homo rhodesiensis reaching Europe are approximately 800 thousand years ago when a type of human referred to as Homo antecessor or Homo cepranensis already inhabited the region[clarification needed]. These two human types may be forerunners to European Homo heidelbergensis; however, stone tools dating from 1.2 to 1.56 million years ago of an unknown creator have been discovered in south-western Europe. The evidence at the Sima de los Huesos (in the Atapuerca cave system on the Iberian Peninsula) suggests Homo heidelbergensis was already in Europe by 600,000 years ago. Molecular phylogenetic analysis[25] suggests Homo rhodesiensis[citation needed] and Homo heidelbergensis continued to intermix until 350,000 years ago, after which they were separate species, and sometime within the last 200,000 years Homo heidelbergensis evolved into Homo neanderthalensis, the classic Neanderthal human. It appears the original Neanderthal population was, in fact, more distantly related to today's human than is Homo heidelbergensis. However, recent evidence of successful interbreeding between Neanderthals and modern humans has made that issue moot, at least insofar as some Neanderthal populations were concerned. Discovery Neander Valley site Neanderthal skulls were first discovered in Engis Caves (fr), in what is now Belgium (1829) by Philippe-Charles Schmerling and in Forbes' Quarry, Gibraltar (1848), both prior to the type specimen discovery in a limestone quarry of the Neander Valley in Erkrath near Düsseldorf in August 1856, three years before Charles Darwin's On the Origin of Species was published.[26] The type specimen, dubbed Neanderthal 1, consisted of a skull cap, two femora, three bones from the right arm, two from the left arm, part of the left ilium, fragments of a scapula, and ribs. The workers who recovered this material originally thought it to be the remains of a bear. They gave the material to amateur naturalist Johann Carl Fuhlrott, who turned the fossils over to anatomist Hermann Schaaffhausen. The discovery was jointly announced in 1857. The original Neanderthal discovery is now considered the beginning of paleoanthropology. These and other discoveries led to the idea these remains were from ancient Europeans who had played an important role in modern human origins. The bones of over 400 Neanderthals have been found since.[27] Timeline 1829: Neanderthal skulls were discovered in Engis, in present-day Belgium.
Early Neanderthals lived in the Last Glacial age for a span of about 100,000 years. Because of the damaging effects the glacial period had on the Neanderthal sites, not much is known about the early species. Countries where their remains are known include most of Europe south of the line of glaciation, roughly along the 50th parallel north, including most of Western Europe, including the south coast of Great Britain,[32] Central Europe and the Balkans,[33] some sites in Ukraine and in western Russia and outside of Europe in the Zagros Mountains and in the Levant. It is estimated that the total Neanderthal population across this habitat range numbered at around 70,000 at its peak. [34] Neanderthal fossils have not been found to date in Africa, but there have been finds rather close to Africa, both at Gibraltar and in the Levant. At some Levantine sites, Neanderthal remains, in fact, date after the same sites were vacated by Homo sapiens. Mammal fossils of the same time period show cold-adapted animals were present alongside these Neanderthals in this region of the Eastern Mediterranean. This implies Neanderthals were better adapted biologically to cold weather than H. sapiens and at times displaced H. sapiens in parts of the Middle East when the climate got cold enough. Homo sapiens appears to have been the only human type in the Nile River Valley during these periods, and Neanderthals are not known to have ever lived south-west of modern Israel. When further climate change caused warmer temperatures, the Neanderthal range likewise retreated to the north along with the cold-adapted species of mammals. Apparently these weather-induced population shifts took place before "modern" people secured competitive advantages over the Neanderthal, as these shifts in range took place well over ten thousand years before "moderns" totally replaced the Neanderthal, despite the recent evidence of some successful interbreeding.[35] There were separate developments in the human line, in other regions such as Southern Africa, that somewhat resembled the European and Western/Central Asian Neanderthals, but these people were not actually Neanderthals. One such example is Rhodesian Man (Homo rhodesiensis) who existed long before any classic European Neanderthals, but had a more modern set of teeth, and arguably some H. rhodesiensis populations were on the road to modern Homo sapiens sapiens. To date, no intimate connection has been found between these similar people and the Western/Central Eurasian Neanderthals, at least during the same time as classic Eurasian Neanderthals, and H. rhodesiensis seems to have evolved separately and earlier than classic Neanderthals in a case of convergent evolution. It appears incorrect, based on present research and known fossil finds, to refer to any fossil outside Europe or Western and Central Asia as a true Neanderthal. True Neanderthals had a known range that possibly extended as far east as the Altai Mountains, but not farther to the east or south, and apparently not into Africa. At any rate, in Africa the land immediately south of the Neanderthal range was possessed by "modern" H. sap., since at least 160,000 years before the present. Classic Neanderthal fossils have been found over a large area, from northern Germany to Israel and Mediterranean countries like Spain[36] and Italy[37] in the south and from England and Portugal in the west to Uzbekistan in the east. This area probably was not occupied all at the same time. The northern border of their range, in particular, would have contracted frequently with the onset of cold periods. On the other hand, the northern border of their range as represented by fossils may not be the real northern border of the area they occupied, since Middle Palaeolithic-looking artifacts have been found even further north, up to 60° N, on the Russian plain.[38] Recent evidence has extended the Neanderthal range by about 1,250 miles (2,010 km) east into southern Siberia's Altai Mountains.[39][40] Anatomy Neanderthal anatomy was more robust than anatomically modern humans and they had less neotenized skulls.[41] Behavior Neanderthals were almost exclusively carnivorous[11][42] and apex predators;[12] however, new studies do indicate that they had cooked vegetables in their diet.[13][43] They made advanced tools,[44] had a language (the nature of which is debated) and lived in complex social groups. Genome Early investigations concentrated on mitochondrial DNA (mtDNA), which, owing to strictly matrilineal inheritance and subsequent vulnerability to genetic drift, is of limited value in evaluating the possibility of interbreeding of Neanderthals with Cro-Magnon people. In 1997, geneticists were able to extract a short sequence of DNA from Neanderthal bones from 30,000 years ago.[45] In July 2006, the Max Planck Institute for Evolutionary Anthropology and 454 Life Sciences announced that they would sequence the Neanderthal genome over the next two years. This genome is expected to be roughly the size of the human genome, three-billion base pairs, and share most of its genes. It was hoped the comparison would expand understanding of Neanderthals, as well as the evolution of humans and human brains.[46] Svante Pääbo has tested more than 70 Neanderthal specimens. Preliminary DNA sequencing from a 38,000-year-old bone fragment of a femur found at Vindija Cave, Croatia, in 1980 showed Homo neanderthalensis and Homo sapiens share about 99.5% of their DNA. From mtDNA analysis estimates, the two species shared a common ancestor about 500,000 years ago. An article[47] appearing in the journal Nature has calculated the species diverged about 516,000 years ago, whereas fossil records show a time of about 400,000 years ago.[48] A 2007 study pushes the point of divergence back to around 800,000 years ago.[49] Edward Rubin of the Lawrence Berkeley National Laboratory in Berkeley, California, states recent genome testing of Neanderthals suggests human and Neanderthal DNA are some 99.5% to nearly 99.9% identical.[50][51] On 16 November 2006, Lawrence Berkeley National Laboratory issued a press release suggesting Neanderthals and ancient humans probably did not interbreed.[52] Edward M. Rubin, director of the U.S. Department of Energy's Lawrence Berkeley National Laboratory and the Joint Genome Institute (JGI), sequenced a fraction (0.00002) of genomic nuclear DNA (nDNA) from a 38,000-year-old Vindia Neanderthal femur. They calculated the common ancestor to be about 353,000 years ago, and a complete separation of the ancestors of the species about 188,000 years ago. Their results show the genomes of modern humans and Neanderthals are at least 99.5% identical, but despite this genetic similarity, and despite the two species having coexisted in the same geographic region for thousands of years, Rubin and his team did not find any evidence of any significant crossbreeding between the two. Rubin said, "While unable to definitively conclude that interbreeding between the two species of humans did not occur, analysis of the nuclear DNA from the Neanderthal suggests the low likelihood of it having occurred at any appreciable level."[53] In 2008 Richard E. Green et al. from Max Planck Institute for Evolutionary Anthropology in Munich, Germany published the full sequence of Neanderthal mitochondrial DNA (mtDNA) and suggested "Neanderthals had a long-term effective population size smaller than that of modern humans."[54] Writing in Nature about Green et al.'s findings, James Morgan asserted the mtDNA sequence contained clues that Neanderthals lived in "small and isolated populations, and probably did not interbreed with their human neighbours."[55][56] In the same publication, it was disclosed by Svante Pääbo that in the previous work at the Max Planck Institute that "Contamination was indeed an issue," and they eventually realized that 11% of their sample was modern human DNA.[57][58] Since then, more of the preparation work has been done in clean areas and 4-base pair 'tags' have been added to the DNA as soon as it is extracted so the Neanderthal DNA can be identified. With 3 billion nucleotides sequenced, analysis of about 1/3 showed no sign of admixture between modern humans and Neanderthals, according to Pääbo. This concurred with the work of Noonan from two years earlier. The variant of microcephalin common outside Africa, which was suggested to be of Neanderthal origin and responsible for rapid brain growth in humans, was not found in Neanderthals. Nor was the MAPT variant, a very old variant found primarily in Europeans.[57] However, an analysis of a first draft of the Neanderthal genome by the same team released in May 2010 indicates interbreeding may have occurred.[4][5] "Those of us who live outside Africa carry a little Neanderthal DNA in us," said Pääbo, who led the study. "The proportion of Neanderthal-inherited genetic material is about 1 to 4 percent. It is a small but very real proportion of ancestry in non-Africans today," says Dr. David Reich of Harvard Medical School in Boston, who worked on the study. This research compared the genome of the Neanderthals to five modern humans from China, France, sub-Saharan Africa, and Papua New Guinea. The finding is that about 1 to 4 percent of the genes of the non-Africans came from Neanderthals, compared to the baseline defined by the two Africans. This indicates a gene flow from Neanderthals to modern humans, i.e., interbreeding between the two populations. Since the three non-African genomes show a similar proportion of Neanderthal sequences, the interbreeding must have occurred early in the migration of modern humans out of Africa, perhaps in the Middle East. No evidence for gene flow in the direction from modern humans to Neanderthals was found. The latter result would not be unexpected if contact occurred between a small colonizing population of modern humans and a much larger resident population of Neanderthals. A very limited amount of interbreeding could explain the findings, if it occurred early enough in the colonization process.[4] While interbreeding is viewed as the most parsimonious interpretation of the genetic discoveries, the authors point out they cannot conclusively rule out an alternative scenario, in which the source population of non-African modern humans was already more closely related to Neanderthals than other Africans were, due to ancient genetic divisions within Africa.[4] Among the genes shown to differ between present-day humans and Neanderthals were RPTN, SPAG17, CAN15, TTF1 and PCD16.[4] Extinction hypotheses The Neanderthals disappear from the fossil record after about 25,000 years ago. The last traces of Mousterian culture (without human specimens) have been found in Gorham's Cave on the remote south-facing coast of Gibraltar, dated 30,000 to 24,500 years ago. Possible scenarios are: Neanderthals were a separate species from modern humans, and became extinct (due to climate change or interaction with humans) and were replaced by H. sapiens moving into its habitat beginning around 80,000 years ago.[60] Competition from H. sapiens probably contributed to Neanderthal extinction.[61] Jared Diamond has suggested a scenario of violent conflict and displacement.[62] mtDNA-based simulation of modern human expansion in Europe starting 1600 generations ago. Neanderthal range in light grey.[66] As Paul Jordan notes: "A natural sympathy for the underdog and the disadvantaged lends a sad poignancy to the fate of the Neanderthal folk, however it came about." Jordan, though, does say that there was perhaps interbreeding to some extent, but that populations that remained totally Neanderthal were likely out-competed and marginalized to extinction by the Aurignacians.[35] Climate change About 55,000 years ago, the weather began to fluctuate wildly from extreme cold conditions to mild cold and back in a matter of a few decades.[citation needed] Neanderthal bodies were well suited for survival in a cold climate—their barrel chests and stocky limbs stored body heat better than the Cro-Magnons. However, the rapid fluctuations of weather caused ecological changes to which the Neanderthals could not adapt. The weather changes were so rapid that within a lifetime, plants and animals someone grew up with would be replaced by completely different plants and animals. Neanderthal's ambush techniques would have failed as grasslands replaced trees. A large number of Neanderthals would have died during these fluctuations, which peaked about 30,000 years ago.[67] Studies on Neanderthal body structures have shown that they needed more energy to survive than any other species. Their energy needs were up to 100-350 calories more per day comparing to projected anatomically modern human males weighing 68.5 kg and females 59.2 kg.[68] When food became scarce, this difference may have played a major role in the Neanderthals' extinction.[67] Coexistence with H. sapiens There is no longer certainty regarding the identity of the humans who produced the Aurignacian culture, even though the presumed westward spread of anatomically modern humans (AMHs) across Europe is still based on the controversial first dates of the Aurignacian. Currently, the oldest European anatomically modern Homo sapiens is represented by a robust modern-human mandible discovered at Peştera cu Oase (southwest Romania), dated to 34,000–36,000 years ago. Human skeletal remains from the German site of Vogelherd, so far regarded as the best association between anatomically modern Homo sapiens and Aurignacian culture, were revealed to represent intrusive Neolithic burials into the Aurignacian levels and subsequently all the key Vogelherd fossils are now dated to 3,900–5,000 years ago instead.[69] As for now, the expansion of the first anatomically modern humans into Europe cannot be located by diagnostic and well-dated AMH fossils "west of the Iron Gates of the Danube" before 32,000 years ago.[70] Consequently, the exact nature of biological and cultural interaction between Neanderthals and other human groups between 50,000 and 30,000 years ago is currently hotly contested.[71] A new proposal strives to resolve the issue by proposing the Gravettians rather than the Aurignacians as the anatomically modern humans who contributed to the Eurasian genetic pool after 30,000 years ago.[71] Correspondingly, the human skull fragment found at the Elbe River bank at Hahnöfersand near Hamburg was once radiocarbon-dated to 36,000 years ago and seen as possible evidence for the intermixing of Neanderthals and anatomically modern humans. It is now dated to the more recent Mesolithic.[72] An alternative to extinction is that Neanderthals were absorbed into the Cro-Magnon population by interbreeding. This would be counter to strict versions of the Recent African Origin, since it would imply that at least part of the genome of Europeans would descend from Neanderthals. The most vocal proponent of the hybridization hypothesis is Erik Trinkaus of Washington University.[73] Trinkaus claims various fossils as hybrid individuals, including the "child of Lagar Velho", a skeleton found at Lagar Velho in Portugal dated to about 24,000 years ago.[74] In a 2006 publication co-authored by Trinkaus, the fossils found in 1952 in the cave of Peștera Muierii, Romania, are likewise claimed as hybrids.[75] An estimated 1 to 4 percent of the DNA in Europeans and Asians (i.e. French, Chinese and Papua probands) is non-modern, and shared with ancient Neanderthal DNA rather than with Sub-Saharan Africans (i.e. Yoruba and San probands).[76] Genetic research now confirms that non-Africans are part Neanderthal,[77][78] due to interbreeding between Neanderthals and the ancestors of non-Africans in the Middle East. Specimens Neanderthal 1: Initial Neanderthal specimen found during an archaeological dig in August 1856. Discovered in a limestone quarry at the Feldhofer grotto in Neanderthal, Germany. The find consisted of a skull cap, two femora, the three right arm bones, two of the left arm bones, ilium, and fragments of a scapula and ribs. Type Specimen, Neanderthal 1 Shanidar 1: Found in the Zagros Mountains in northern Iraq; a total of nine skeletons found believed to have lived in the Middle Paleolithic. One of the nine remains was missing part of its right arm; theorized to have been broken off or amputated. The find is also significant because it shows that stone tools were present among this tribe's culture. One was buried with flowers, showing that some type of burial ceremony may have occurred.
Bones with Neanderthal traits in chronological order. (Sorted by time) Mixed with H. heidelbergensis traits > 350 ka: Sima de los Huesos c. 500:350 ka ago[79][80]
135–45 ka: Krapina, Saccopastore, Malarnaud, Altamura, Gánovce, Denisova, Okladnikov Altai, Pech de l'Azé, Tabun 120 ka – 100±5 ka,[82] Qafzeh9 100, Shanidar 1 to 9 80–60 ka, La Ferrassie 1 70 ka, Kebara 60 ka, Régourdou, Mt. Circeo, Combe Grenal, Erd 50 ka, La Chapelle-aux Saints 1 60 ka, Amud I 53±8 ka,[83][84] Teshik-Tash. Mixed with AMH traits < 35 Pestera cu Oase 35 ka, Mladeč 31 ka, Pestera Muierii 30 ka (n/s),[88] Lagar Velho 24.5 ka. Popular culture Neanderthals often appear in popular culture, often in unflattering and inaccurate light, much in the same way as "dinosaur" is also used.[citation needed] References ^ a b Tattersall I, Schwartz JH (June 1999). "Hominids and hybrids: the place of Neanderthals in human evolution". Proceedings of the National Academy of Sciences 96 (13): 7117–9. Bibcode 1999PNAS...96.7117T. doi:10.1073/pnas.96.13.7117. PMC 33580. PMID 10377375. Retrieved 17 May 2009. Journals Boë, Louis-Jean; Jean-Louis Heim, Kiyoshi Honda and Shinji Maeda (July 2002). "The potential Neandertal vowel space was as large as that of modern humans". Journal of Phonetics 30 (3): 465–484. doi:10.1006/jpho.2002.0170.[dead link] Bibliography Derev'anko, Anatoliy P.; William Roger Powers and Demitri Boris Shimkin (1998). The Paleolithic of Siberia: new discoveries and interpretations. Novosibirsk: Institute of Anthropology and Ethnography. ISBN 0252020529. OCLC 36461622. Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License |
|
