Fossil range: Pleistocene
|H. neanderthalensis, La Chapelle-aux-Saints|
|Mounted Neanderthal skeleton, American Museum of Natural History|
|Range of Homo neanderthalensis. Eastern and northern ranges may be extended to include Okladnikov in Altai and Mamotnaia in Ural|
The Neanderthal (pronounced /ni(ː)ˈændərtɑːl/, /ni(ː)ˈændərθɔːl/), or /neɪˈændərtɑːl/), also spelled Neandertal, is an extinct member of the Homo genus that is known from Pleistocene specimens found in Europe and parts of western and central Asia. Neanderthals are either classified as a subspecies of humans (Homo sapiens neanderthalensis) or as a separate species (Homo neanderthalensis). The first proto-Neanderthal traits appeared in Europe as early as 600,000–350,000 years ago.
Proto-Neanderthal traits are occasionally grouped to 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 30,000 years ago.
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 32,000 and 33,000 years ago. No definite specimens younger than 30,000 years ago have been found; however, evidence of fire by Neanderthals at Gibraltar indicate that 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.
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. 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 Homo sapiens, perhaps larger, indicating their brain size may have been comparable as well. In 2008, a group of scientists made a study using three-dimensional computer-assisted reconstructions of Neanderthal infants based on fossils found in Russia and Syria that shows that they had brains as large as ours at birth and larger than ours as adults. On average, the height of Neanderthals was comparable to contemporaneous Homo sapiens. Neanderthal males stood about 165–168 cm (65–66 in) and were heavily built with robust bone structure. They were much stronger, having particularly strong arms and hands. Females stood about 152–156 cm (60–61 in). They were almost exclusively carnivorous and apex predators.
The Neanderthal is named after the Neandertal valley, originally spelled Neanderthal, which is located about 12 km (7.5 mi) east of Düsseldorf. The spelling of the German word Thal ("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, the modern spelling with t is however otherwise used in referring both to the hominid and the valley.
The valley itself was named after the theologian Joachim Neander, who lived nearby in Düsseldorf in the late 17th century. "Neander" is a classicized form of the common German surname Neumann. In turn, the hominid was named after the valley, where the first Neanderthal remains were found. The term Neanderthal Man was coined in 1863 by the Anglo-Irish geologist William King.
The German pronunciation (regardless of spelling) is with the sound /t/. American English speakers commonly pronounce it as /θ/ (th as in thin), but American scientists usually use /t/. British English speakers usually pronounce it as /t/ followed by a long a as in tar, matching the German pronounciation.
For some time, scientists have debated whether Neanderthals should be classified as Homo neanderthalensis or as Homo sapiens neanderthalensis, the latter placing Neanderthals as a subspecies of Homo sapiens. Some morphological studies support that Homo neanderthalensis is a separate species and not a subspecies. Others, for example University of Cambridge Professor Paul Mellars, say "no evidence has been found of cultural interaction" and evidence from mitochondrial DNA studies have been interpreted as evidence Neanderthals were not a subspecies of H. sapiens.
The current state of sequence analysis of the Neanderthal genome suggest there was no recent genetic exchange between Neanderthals and humans, previous results which showed some similarities have now been conclusively shown as contamination and improper phylogenetic assumptions. Consequently, Homo neanderthalensis at present appears to be the correct nomenclature.
Neanderthals evolved from African apes along a path similar to humans. Sometime between 5 and 10 million years ago a common ancestral species between chimps and humans lived in Africa. The ancestor evolved along a path that might include Ardipithecus kadabba, Ardipithicus ramidus, Australopithecus anamensis, Australopithecus afarensis, Homo habilis, Homo ergaster (or Homo erectus). The last common ancestor between anatomically modern Homo sapiens and Neanderthals appears to be an African variant of Homo heidelbergensis known as Homo rhodesiensis, named after an archaic Homo sapiens, 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. 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 Southwestern Europe. The evidence at the Sima de los Huesos (in the Atapuerca cave system on the Iberian Peninsula) suggest that Homo heidelbergensis was already in Europe by 600,000 years ago.
The molecular phylogenetics suggest that Homo rhodesiensis 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 man. If it is proven by further scientific research that Neanderthals provided no significant genetic input into modern populations of Homo sapiens, then it must be assumed that Neanderthal in fact is more distantly related to today's human than is Homo heidelbergensis.
Neanderthal skulls were first discovered in Engis, Belgium (1829) by Philippe-Charles Schmerling and in Forbes' Quarry, Gibraltar (1848), both prior to the "original" 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.
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 that 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.
Bones with Neanderthal traits in chronological order.
Early Neanderthals lived in the Last Glacial age for a span of about 100,000 years. Because of the damaging effects which the glacial period had on the Neanderthal sites, not much is known about the early species. Countries where their remains are known include Portugal, Ukraine, Gibraltar, France, Spain, Britain, Germany, Czech Republic, Slovakia, Croatia, Greece, Iraq, Israel, Iran, Romania and Russia.
Neanderthal fossils have to date not been found in Africa, but rather close to Africa, found in the area of modern Israel. At some sites in the Holy Land region, Neanderthal remains in fact date after the same sites were vacated by Homo sapiens. Mammal fossils of the same time period show that 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. sap. and at times displaced H. sap. 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 southwest 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 Neanderthals.
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 of 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 and Italy 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. Recent evidence has extended the Neanderthal range by about 1,250 miles (2,010 km) east into southern Siberia's Altay Mountains.
Neanderthals were generally only 12–14 cm (5–6 in) shorter than modern humans, contrary to a common view of them as "very short" or "just over 5 feet". Based on 45 long bones from (at most) 14 males and 7 females, Neanderthal males averaged 164–168 cm (65–66 in) and females 152–156 cm (60–61 in) tall. Compared to Europeans some 20,000 years ago, it is nearly identical, perhaps slightly taller. Considering the body build of Neanderthals, new body weight estimates show they are only slightly above the cm/weight or the body mass index of modern Americans or Canadians.
Neanderthals had more robust build and distinctive morphological features, especially of the cranium, which gradually accumulated more derived aspects, particularly in certain relatively isolated geographic regions. Evidence suggests they were much stronger than modern humans; their relatively robust stature is thought to be an adaptation to the cold climate of Europe during the Pleistocene epoch.
The magnitude of autapomorphic traits in specimens differ in time. In the latest specimens, autapomorphy is fuzzy. The following is a list of physical traits which distinguish Neanderthals from modern humans; however, not all of them can be used to distinguish specific Neanderthal populations, from various geographic areas or periods of evolution, from other extinct humans. Also, many of these traits occasionally manifest in modern humans, particularly among certain ethnic groups traced to Neanderthal habitat ranges. Nothing is certain (from unearthed bones) about the shape of soft parts such as eyes, ears, and lips of Neanderthals.
When comparing traits to worldwide average present day human traits in Neanderthal specimens, the following traits are distinguished. The magnitude on particular trait changes with 300,000 years timeline. The large number of classic Neanderthal traits is significant because extreme examples of Homo sapiens may sometimes show one or more of these traits, but not most or all of them.
Within the west Asian and European record there are five broad groups of pathology or injury noted in Neanderthal skeletons.
Neanderthals seemed to suffer a high frequency of fractures, especially common on the ribs (Shanidar IV, La Chapelle-aux-Saints 1 ‘Old Man’), the femur (La Ferrassie 1), fibulae (La Ferrassie 2 and Tabun 1), spine (Kebara 2) and skull (Shanidar I, Krapina, Sala 1). These fractures are often healed and show little or no sign of infection, suggesting that injured individuals were cared for during times of incapacitation. It has been remarked that Neanderthals showed a frequency of such injuries comparable to that of modern rodeo professionals, showing frequent contact with large, combative mammals. The pattern of fractures, along with the absence of throwing weapons, suggests that they may have hunted by leaping onto their prey and stabbing or even wrestling it to the ground.
Particularly related to fractures are cases of trauma seen on many skeletons of Neanderthals. These usually take the form of stab wounds, as seen on Shanidar III, whose lung was probably punctured by a stab wound to the chest between the 8th and 9th ribs. This may have been an intentional attack or merely a hunting accident; either way the man survived for some weeks after his injury before being killed by a rock fall in the Shanidar cave. Other signs of trauma include blows to the head (Shanidar I and IV, Krapina), all of which seemed to have healed, although traces of the scalp wounds are visible on the surface of the skulls.
Arthritis is particularly common in the older Neanderthal population, specifically targeting areas of articulation such as the ankle (Shanidar III), spine and hips (La Chapelle-aux-Saints ‘Old Man’), arms (La Quina 5, Krapina, Feldhofer) knees, fingers and toes. This is closely related to degenerative joint disease, which can range from normal, use-related degeneration to painful, debilitating restriction of movement and deformity and is seen in varying degree in the Shanidar skeletons (I–IV).
Dental enamel hypoplasia is an indicator of stress during the development of teeth and records in the striations and grooves in the enamel periods of food scarcity, trauma or disease. A study of 669 Neanderthal dental crowns showed that 75% of individuals suffered some degree of hypoplasia and that nutritional deficiencies were the main cause of hypoplasia and eventual tooth loss. All particularly aged skeletons show evidence of hypoplasia and it is especially evident in the Old Man of La Chapelle-aux-Saints and La Ferrassie 1 teeth.
Evidence of infections on Neanderthal skeletons is usually visible in the form of lesions on the bone, which are created by systematic infection on areas closest to the bone. Shanidar I has evidence of the degenerative lesions as does La Ferrassie 1, whose lesions on both femora, tibiae and fibulae are indicative of a systemic infection or carcinoma (malignant tumour/cancer).
Neanderthal children may have grown faster than modern human children. Modern humans have the slowest body growth of any mammal during childhood (the period between infancy and puberty) with lack of growth during this period being made up later in an adolescent growth spurt. The possibility that Neanderthal childhood growth was different was first raised in 1928 by the excavators of the Mousterian rock-shelter of a Neanderthal juvenile. Arthur Keith in 1931 wrote, "Apparently Neanderthal children assumed the appearances of maturity at an earlier age than modern children." The earliness of body maturation can be inferred from the maturity of a juvenile's fossile remains and estimated age of death.
The age at which juveniles die can be indirectly inferred from their tooth morphology, development and emergence. This has been argued to both support and question the existence of a maturation difference between Neanderthals and modern humans. Since 2007 tooth age can be directly calculated using the noninvasive imaging of growth patterns in tooth enamel by means of x-ray synchrotron microtomography.
This research supports the existence of a much quicker physical development in Neanderthals than in modern human children. The x-ray synchrotron microtomography study of early H. sapiens sapiens argues that this difference existed between the two species as far back as 160,000 years before present.
The idea that Neanderthals lacked complex language was widespread, despite concerns about the accuracy of reconstructions of the Neanderthal vocal tract, until 1983, when a Neanderthal hyoid bone was found at the Kebara Cave in Israel. The hyoid is a small bone which connects the musculature of the tongue and the larynx, and by bracing these structures against each other, allows a wider range of tongue and laryngeal movements than would otherwise be possible. The presence of this bone implies that speech was anatomically possible. The bone which was found is virtually identical to that of modern humans.
The morphology of the outer and middle ear of Neanderthal ancestors, Homo heidelbergensis, found in Spain, suggests they had an auditory sensitivity similar to modern humans and very different from chimpanzees. They were probably able to differentiate between many different sounds.
Neurological evidence for potential speech in neanderthalensis exists in the form of the hypoglossal canal. The canal of neanderthalensis is the same size or larger than in modern humans, which are significantly larger than the canal of australopithecines and modern chimpanzees. The canal carries the hypoglossal nerve, which controls the muscles of the tongue. This indicates that neanderthalensis had vocal capabilities similar to modern humans. A research team from the University of California, Berkeley, led by David DeGusta, suggests that the size of the hypoglossal canal is not an indicator of speech. His team's research, which shows no correlation between canal size and speech potential, shows there are a number of extant non-human primates and fossilized australopithecines which have equal or larger hypoglossal canal.
Another anatomical difference between Neanderthals and modern humans is the former's lack of a mental protuberance (the point at the tip of the chin). This may be relevant to speech as the mentalis muscle contributes to moving the lower lip and is used to voice a bilabial click. While some Neanderthal individuals do possess a mental protuberance, their chins never show the inverted T-shape of modern humans. In contrast, some Neanderthal individuals show inferior lateral mental tubercles (little bumps at the side of the chin).
Steven Mithen (2006) proposes that the Neanderthals had an elaborate proto-linguistic system of communication which was more musical than modern human language, and which predated the separation of language and music into two separate modes of cognition.
Neanderthal and Middle Paleolithic archaeological sites show a smaller and different toolkit than those which have been found in Upper Paleolithic sites, which were perhaps occupied by modern humans which superseded them. Fossil evidence indicating who may have made the tools found in Early Upper Paleolithic sites is still missing.
Neanderthals are thought to have used tools of the Mousterian class, which were often produced using soft hammer percussion, with hammers made of materials like bones, antlers, and wood, rather than hard hammer percussion, using stone hammers. A result of this is that their bone industry was relatively simple. However, there is good evidence that they routinely constructed a variety of stone implements. Neanderthal (Mousterian) tools most often consisted of sophisticated stone-flakes, task-specific hand axes, and spears. Many of these tools were very sharp. There is also good evidence that they used a lot of wood, objects which are unlikely to have been preserved until today.
There is some evidence for interpersonal violence among Neandertals. A 36,000-year-old Neadertal skull found near St. Césaire has a healed fracture in its cranial vault that was most likely caused by the impact of a sharp implement. The location of the wound suggests interpersonal violence rather than an accident. Because the wound healed, we know that the individual survived the attack.
Also, while they had weapons, whether they had implements which were used as projectile weapons is controversial. They had spears, made of long wooden shafts with spearheads firmly attached, but they are thought by some to have been thrusting spears. Still, a Levallois point embedded in a vertebra shows an angle of impact suggesting that it entered by a "parabolic trajectory" suggesting that it was the tip of a projectile. Moreover, a number of 400,000-year-old wooden projectile spears were found at Schöningen in northern Germany. These are thought to have been made by the Neanderthal's ancestors, Homo erectus or Homo heidelbergensis. Generally, projectile weapons are more commonly associated with H. sapiens. The lack of projectile weaponry is an indication of different sustenance methods, rather than inferior technology or abilities. The situation is identical to that of native New Zealand Māori — modern Homo sapiens, who also rarely threw objects, but used spears and clubs instead.
Although much has been made of the Neanderthals' burial of their dead, their burials were less elaborate than those of anatomically modern humans. The interpretation of the Shanidar IV burials as including flowers, and therefore being a form of ritual burial, has been questioned. On the other hand, five of the six flower pollens found with Shanidar IV are known to have had 'traditional' medical uses, even among relatively recent 'modern' populations. In some cases Neanderthal burials include grave goods, such as bison and aurochs bones, tools, and the pigment ochre.
Neanderthals also performed many sophisticated tasks which are normally associated only with humans. For example, it is known that they controlled fire, constructed complex shelters, and skinned animals. A trap excavated at La Cotte de St Brelade in Jersey gives testament to their intelligence and success as hunters.
Particularly intriguing is a hollowed-out bear femur with holes which may have been deliberately bored into it, known as the Divje Babe flute. This bone was found in western Slovenia in 1995, near a Mousterian fireplace, but its significance is still a matter of dispute. Some paleoanthropologists have hypothesized that it was a musical instrument, while others believe it was created by accident through the chomping action of another bear; or possibly was in fact not the work of Neanderthals.
Pendants and other jewelry showing traces of ochre dye and of deliberate grooving have also been found with later finds, particularly in France but whether or not they were created by Neanderthals or traded to them by Cro-Magnons is a matter of controversy.
Neanderthals hunted large animals, such as the mammoth. Stone-tipped wooden spears were used for hunting and stone knives and poleaxes were used for butchering the animals or as weapons. However, they are believed to have practiced cannibalism, or ritual defleshing. This hypothesis has been represented after researchers found marks on Neanderthal bones similar to the bones of a dead deer butchered by Neanderthals.
Intentional burial and the inclusion of grave goods are the most typical representations of ritual behavior in the Neanderthals and denote a developing ideology. However, another much debated and controversial manifestation of this ritual treatment of the dead comes from the evidence of cut-marks on the bone which has 'historically been viewed' as evidence of ritual defleshing.
Neanderthal bones from various sites (Combe-Grenal and Abri Moula in France, Krapina in Croatia and Grotta Guattari in Italy) have all been cited as bearing cut marks made by stone tools. However, results of technological tests reveal varied causes.
Re-evaluation of these marks using high-powered microscopes, comparisons to contemporary butchered animal remains, and recent ethnographic cases of excarnation mortuary practises have shown that perhaps this was a case of ritual defleshing.
The evidence indicating cannibalism would not distinguish Neanderthals from modern Homo sapiens. Ancient and existing Homo sapiens are known to have practiced cannibalism (e.g. the Korowai) and/or mortuary defleshing (e.g. the sky burial of Tibet).
Grooves in bones are hypothesized to be cuts by Neanderthal tools, not animal teeth. The chances of them being random, as some writers attributing them to animals have proposed, is debated.
A 2009 report in the Proceedings of the National Academy of Sciences (PNAS) on two archaeological sites in the Murcia province of southern Spain, records the discovery of shells showing pigment residues and concludes that these were used by the Neanderthals as make-up containers. Sticks of the black pigment manganese have previously been discovered in Africa. These may have been used as body paint by Neanderthals.
Previous investigations concentrated on mitochondrial DNA (mtDNA), which, owing to strictly matrilineal inheritance and subsequent vulnerability to genetic drift, is of limited value to disprove interbreeding of Neanderthals with Cro-Magnon people.
In July 2006, the Max Planck Institute for Evolutionary Anthropology and 454 Life Sciences announced that they would be sequencing the Neanderthal genome over the next two years. This genome is very likely to be roughly the size of the human genome, three-billion base pairs, and probably shares most of its genes. It is thought a comparison will expand understanding of Neanderthals as well as the evolution of humans and human brains.
Svante Pääbo has tested more than 70 Neanderthal specimens and found only one which had enough DNA to sample. Preliminary DNA sequencing from a 38,000-year-old bone fragment of a femur found at Vindija cave, Croatia, in 1980 shows that 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 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. Scientists hope the DNA records will answer the question of whether there was interbreeding among the species. A 2007 study pushes the point of divergence back to around 800,000 years ago.
Edward Rubin of the Lawrence Berkeley National Laboratory in Berkeley, California states that recent genome testing of Neanderthals suggests human and Neanderthal DNA are some 99.5% to nearly 99.9% identical.
On 16 November 2006, Lawrence Berkeley National Laboratory issued a press release suggesting that Neanderthals and ancient humans probably did not interbreed. 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 bone. 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."
In 2008 Richard E. Green et al. from Max Planck Institute for Evolutionary Anthropology published the full sequence of Neanderthal mitochondrial DNA (mtDNA) and suggested that "Neandertals had a long-term effective population size smaller than that of modern humans." Writing in Nature about Green et al.'s findings, James Morgan asserted that the mtDNA sequence contained clues that Neanderthals lived in "small and isolated populations, and probably did not interbreed with their human neighbours."
In the same publication, it was disclosed that the previous work at Max Plank Institute that according to Svante Pääbo "Contamination was indeed an issue," and eventually realized that 11% of their sample was modern human DNA. Since then, more of the preparation work is done in clean areas and 4-base pair 'tags' are 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 1/3rd shows that there is no sign of admixture between modern humans and Neanderthals, according to Pääbo. This concurs with the work of Noonan from two years earlier. The variant of Microcephalin common outside Africa, which was attributed to rapid brain growth in humans and suggested to be of Neanderthal origin, was not found in Neanderthals. Nor was the MAPT variant, a very old variant found primarily in Europeans.
Possible hypotheses for the fate of Neanderthals include the following:
Since the 1990s there has been a consensus on the recent African origin of modern humans, based on evidence from mitochondrial DNA. This consensus precludes possibility three.
According to the Out of Africa theory, modern humans (Homo sapiens) began replacing Neanderthals around 45,000 years ago, as the Cro-Magnon people appeared in Europe, pushing populations of Neanderthals into regional pockets, such as modern-day Croatia, Iberia and the Crimean peninsula, where they held on for thousands of years. 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. Proponents of this model believe that modern humans and Neanderthals were separate species that were not inter-fertile. They cite the following evidence:
Neanderthals, according to Jordan (2001), appear to have had psychological traits that worked well in their early history but finally placed them at a long-term disadvantage with regards to modern humans. Jordan is of the opinion that the Neanderthal mind was sufficiently different from that of Homo sapiens to have been "alien" in the sense of thinking differently from that of modern humans, despite the obvious fact that Neanderthals were highly intelligent, with a brain as large or larger than our own. This theory is supported by what Neanderthals possessed, and just as importantly, by what they lacked, in cultural attributes and manufactured artifacts. Essentially, the Neanderthals lost out because their behaviors and tools eventually became second-rate.
There once was a time when both human types shared essentially the same Mousterian tool kit and neither human type had a definite competitive advantage, as evidenced by the shifting Homo sapiens/Neanderthal borderland in the Middle East. But finally Homo sapiens started to attain behavioral or cultural adaptations that allowed "moderns" an advantage. There are early glimmers of this from Zaire where in the area of Katanda bone harpoon points have been found of fine workmanship, dating to perhaps 80,000 years ago. These featured backwards-pointing barbs and lateral grooves so they could be easily installed on a wooden shaft, used to harpoon local fish. These appear to have been made by modern humans and make for a more sophisticated spear than any that Neanderthals are known to have made. Jordan admits some of these innovations were "flash in the pan" local affairs that faded away for awhile, but there does not seem much question that Homo sapiens in Africa was taking steps toward better tools and a more complex social life, while the Neanderthal ways and technology remained the same. It is noted that fishing was never much of a Neanderthal accomplishment (they did eat fish on occasion) but is more a behavior of modern human types. There is an example of a barbed point made from bone, evidently made by a Neanderthal, but such finds are very rare. Per Jordan the Neanderthals made wooden and stone artifacts, but bone and ivory ones were not common, implying that the Neanderthal mind tended to be rather resistant to learning new methods or materials.
Neanderthal people mastered complex tasks such as the making of fire, shelters with post holes, and stone tools. In their later career Neanderthals appear to have sometimes buried their dead and their placement of Cave Bear bones in order shows some sort of reverence or perhaps religion toward this animal. Yet there were many Cro-Magnon tools and behaviors that the Neanderthals seem to have never developed: organized fishing, using fish hooks and fish nets; headgear or hats, shoes, sewn clothing, needle-and-thread, and long-distance trade. It is still debated whether Neanderthals had significant art or music.
Other researchers think that the Neanderthals had little sexual division of labor, with Neanderthal women alongside the men hunting big game. Such a lifestyle was not as energy efficient as that of modern humans, whose hunter-gatherer lifestyle secured supplemental food of a much greater variety, including plant materials such as tubers or wild grains, fish, edible fungi, and small edible animals secured by women, young boys/girls and elderly men, while males in the prime of life could hunt big mammals. Since the Neanderthals were mostly carnivorous and targeting big mammals, a shortage of large mammals meant possible bouts of starvation or malnutrition, which affected Cro-Magnon people less. The Neanderthals appear to have stored food against lean times much less than Cro-Magnon people did. Neanderthals got food in a haphazard, catch-as-catch-can manner. In addition, the Cro-Magnon sites show a lot of animal remains of small creatures best hunted with traps and snares, such as squirrels and rabbits, whereas Neanderthal sites show few such fossils. In short, inferior methods shut Neanderthals out of many food sources that Cro-Magnons exploited.
Cro-Magnons could carry more people on the land than Neanderthals could, and one may infer that Cro-Magnons would have familial and tribal organization that Neanderthals could not match, if they had the latter at all.
Neanderthals appear to have never used boats or rafts, as evidenced by the lack of Neanderthal fossils from North Africa, yet in stark contrast Homo erectus, their more primitive ancestor, appears to have used rafts or some other sort of boat on occasion. Homo erectus, or some other hominid, used such craft to reach the island of Flores as evidenced by the discovery of Homo floresiensis in 2003. Flores and some other places Homo erectus reached have always been surrounded by very deep water, proving the use of watercraft of some sort.
Since the Neanderthals evidently never used watercraft, but prior and/or arguably more primitive editions of humanity did, there is argument that Neanderthals represent a highly specialized side branch of the human tree, relying more on physiological adaptation than psychological adaptation in daily life than "moderns". Specialization has been seen before in other hominims, such as Paranthropus boisei which evidently was adapted to eat rough vegetation.
Additionally, Neanderthals evidently had little long-term planning when securing food. French caves show almost no salmon bones during Neanderthal occupancy but large numbers during Cro-Magnon occupancy. In contrast, Cro-Magnons planned for salmon runs months ahead of time, getting enough people together at just the right time and place to catch a lot of fish. Neanderthals appear to have had little to no social organization beyond the immediate family unit. Why Neanderthal psychology was different from the modern humans that they coexisted with for millennia is not known.
Due to the paucity of symbolism that Neanderthal artifacts show, Neanderthal language probably did not deal much with a verbal future tense, again restricting Neanderthal exploitation of resources. Cro-Magnon people had a much better standard of living than the hardscrabble existence available to Neanderthals. With better language skills and bigger social groups, a better psychological repertoire, and better planning, Cro-Magnon people, living alongside the Neanderthals on the same land, outclassed them in terms of life span, population, available spare time (as shown by Cro-Magnon art), physical health and lower rate of injury, infant mortality, comfort, quality of life, and food procurement. The advantages held by Cro-Magnon people let them by this time to thrive in worse climatic conditions than their Neanderthal counterparts. As weather worsened about 30,000 years ago, Jordan notes it would have taken only one or two thousand years of inferior Neanderthal skills to cause them to go extinct, in light of better Cro-Magnon performance in all these areas.
Jordan states the Chatelperronian tool tradition suggests Neanderthals were making some attempts at advancement, as Chatelperronian tools are only associated with Neanderthal remains. It appears this tradition was connected to social contact with Cro-Magnons of some sort. There were some items of personal decoration found at these sites, but these are inferior to contemporary Cro-Magnon items of personal decoration and arguably were made more by imitation than by a spirit of original creativity. At the same time, Neanderthal stone tools were sometimes finished well enough to show some aesthetic sense. As 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."
One theory is that that Neanderthals and "moderns" could interbreed and produce fertile offspring, but that psychological/behavioural differences, as well as differences in language and appearance, prevented sexual attraction between these two human types; or that Neanderthals were different enough that there was little to no sexual contact at all, or if so, that there were no fertile offspring with any live offspring being sterile, like mules. If there were any fertile hybrid offspring, it is possible that the greater numbers of Homo sapiens simply drowned out the Neanderthal input or that Neanderthal traits were later "weeded out" of the hybrid population by natural or sexual selection.
The validity of such an extensive period of cornered Neanderthal groups is recently questioned. 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 Pestera cu Oase (south-west Romania), dated to 34–36 thousand years ago. Human skeletal remains from the German site of Vogelherd, so far regarded 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 3.9–5.0 thousand years ago instead. 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 thousand years ago.
Consequently, the exact nature of biological and cultural interactions between Neanderthals and other human groups between 50 and 30 thousand years ago is currently hotly contested. A new proposal resolves the issue by taking the Gravettians rather than the Aurignacians as the anatomically modern humans which contributed to the Eurasian genetic pool after 30 thousand years ago. 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.
Modern-human findings in Abrigo do Lagar Velho, Portugal of 24,500 years ago, allegedly featuring Neanderthal admixtures, have been published. However the interpretation of the Portuguese specimen is disputed.
In another study, researchers have recently found in Pestera Muierii, Romania, remains of European humans from 30 thousand years ago who possessed mostly diagnostic "modern" anatomical features, but also had distinct Neanderthal features not present in ancestral modern humans in Africa, including a large bulge at the back of the skull, a more prominent projection around the elbow joint, and a narrow socket at the shoulder joint. Analysis of one skeleton's shoulder showed that these humans, like Neanderthal, did not have the full capability for throwing spears.
The paleontological analysis of modern-human emergence in Europe has been shifting from considerations of the Neanderthals to assessments of the biology and chronology of the earliest modern humans in western Eurasia. This focus, involving morphologically modern humans before 28,000 years ago, shows accumulating evidence that they present a variable mosaic of derived modern human, archaic human, and Neanderthal features. Studies of fossils from the upper levels of the Sima de las Palomas, Murcia, Spain, dated to 40,000 years ago, establish the late persistence of Neanderthals in Iberia. This reinforces the conclusion that the Neanderthals were not merely swept away by advancing modern humans. In addition, the Palomas Neanderthals variably exhibit a series of modern-human features rare or absent in earlier Neanderthals. Either they were evolving on their own towards the modern-human pattern, or more likely, they had contact with early modern humans around the Pyrenees. If the latter, it implies that the persistence of the Middle Paleolithic in Iberia was a matter of choice, and not cultural retardation.
In popular idiom the word neanderthal is sometimes used as an insult, to suggest that a person combines a deficiency of intelligence and an attachment to brute force, as well as perhaps implying the person is old fashioned or attached to outdated ideas, much in the same way as "dinosaur" is also used. Although they are frequently characterized in this manner, research showing Neanderthals were as intelligent as contemporaneous Homo sapiens, with early stone tool technologies of comparable efficiency, is debunking long-held beliefs.
Counterbalancing this are sympathetic literary portrayals of Neanderthals, as in the novel The Inheritors by William Golding, Isaac Asimov's The Ugly Little Boy, and Jean M. Auel's Earth's Children series, though Auel repeatedly compares Neanderthals to modern humans unfavorably within the series, showing them to be less advanced in nearly every facet of their lives. Instead she gives them access to a 'race memory' and uses it to explain both their cultural richness and eventual stagnation. A more serious treatment is offered by Finnish palaeontologist Björn Kurtén, in several works including Dance of the Tiger, and British psychologist Stan Gooch in his hybrid-origin theory of humans. The Neanderthal Parallax, a trilogy of science fiction novels dealing with Neanderthals, written by Robert J. Sawyer, explores a scenario where Neanderthals are seen as a distinct species from humans and survive in a parallel universe version of earth. The novels explore what happens when they, having developed a sophisticated technological culture of their own, open a portal to this version of the earth. The three novels are titled Hominids, Humans, and Hybrids, respectively, and together form essentially one story.
In the Thursday Next series of novels by Jasper Fforde, a small population of Neanderthals were re-created in modern Britain by advanced cloning techniques in the later years of the twentieth century. These fictional Neanderthals have equivalent intelligence to normal humans, but have a radically different culture in which aggression and competition are virtually unthinkable.