Neanderthals (pronounced nee-AN-dər-TAHL or nay-THAHL; scientific name Homo neanderthalensis) were an extinct group of early humans who lived in Europe and parts of Asia during the Middle to Late Pleistocene era. They disappeared around 40,000 years ago when modern humans, known as Cro-Magnons, arrived in their regions. However, some Neanderthals in Gibraltar may have survived for thousands of years longer.
The first Neanderthal fossil, called Neanderthal 1, was found in 1856 in a valley in Germany. At first, scientists thought it belonged to a group considered lower in old racial classifications. As more fossils were discovered in the early 20th century, Neanderthals were described as a distinct species with less developed features, especially by scientist Marcellin Boule. By the middle of the 20th century, people believed human evolution followed a path from ape-like ancestors through a "Neanderthal phase" to modern humans. This idea helped form the "Out of Africa" theory in the 1970s. In 2010, scientists studied the Neanderthal genome and found evidence that Neanderthals interbred with modern humans.
Neanderthals had a long, low skull, thick brow ridges, a bony bump at the back of the skull, strong teeth and jaws, wide chests, and short limbs. These traits became more common in Europe during the Middle Pleistocene, possibly due to natural selection in cold climates and genetic changes during ice ages. Neanderthals ranged in height from about 147.5 to 177 cm (4 ft 10 in to 5 ft 10 in), with average males measuring about 165 cm (5 ft 5 in) and weighing 75 kg (165 lb). Their brain size was larger than that of modern humans—1,640 cc (100 cu in) for males and 1,460 cc (89 cu in) for females—but their brain structures differed from modern humans in areas linked to thinking and language. This may explain why Neanderthal behavior, as seen in archaeological finds, appears simpler compared to Cro-Magnons.
Neanderthals had small populations and faced challenges from inbreeding, which may have slowed their technological progress. They made Mousterian stone tools (a type of Middle Paleolithic tool) and may have worn blankets or ponchos. They likely used fire and ate what was available near their homes, including large animals, plants, and mushrooms. Neanderthals often suffered from serious injuries and attacks by animals. Some Paleolithic art, such as possible ornaments made from bird claws and feathers, collections of unusual items like crystals and fossils, and engravings, have been linked to Neanderthals, though the evidence is not certain. Neanderthals buried their dead, but there is no clear proof they believed in life after death.
Taxonomy
Neanderthals are named after the Neander Valley, where the first known Neanderthal remains were found. The valley was originally called Neanderthal, and the species was called Neanderthaler in German until a spelling change in 1901. In English, the species is sometimes spelled Neandertal, but the scientific name, Homo neanderthalensis, is always written with "th" because of a rule called the principle of priority. In German, the species is called Neandertaler, meaning "inhabitant of the Neander Valley," while Neandertal always refers to the valley itself. The valley was named after Joachim Neander, a 17th-century German theologian and hymn writer. His grandfather changed the family name from Neumann ("new man") to Neander, inspired by the Greek word for "man."
The "th" in Neanderthal can be pronounced like the "t" in "think" (as in German) or like the "th" in "think" (as in English).
The first Neanderthal specimen, called Neanderthal 1, was known as the "Neanderthal cranium" or "Neanderthal skull" in scientific studies. The name Homo neanderthalensis was first proposed in 1863 by William King, an Irish geologist. He used the name "Neanderthal man" for the species and claimed it was different from modern humans. However, King later suggested Neanderthals and modern humans should be classified in separate groups, as he compared their braincases to those of chimpanzees and thought Neanderthals lacked the ability to think morally or theistically.
Before scientists fully understood how old Neanderthals were, many fossils were found. The first Neanderthal remains—Engis 2 (a skull)—were discovered in 1829 by Philippe-Charles Schmerling in Belgium. He believed these bones were buried at the same time as extinct animal remains. In 1848, a skull from Gibraltar was thought to belong to a modern human.
In 1856, a local teacher named Johann Carl Fuhlrott found bones in the Neander Valley, which he gave to Hermann Schaaffhausen for study. These bones included parts of the skull, thigh bones, arm, and hip. After Charles Darwin’s On the Origin of Species (1859), Fuhlrott and Schaaffhausen argued Neanderthals were an early form of humans, more similar to apes and other human groups. However, some scientists, like Rudolf Virchow, disagreed, saying Neanderthals were not a separate species. Virchow mistakenly believed Neanderthal traits showed signs of aging or disease, which slowed research until the early 1900s.
By the early 1900s, many Neanderthal fossils were found, proving Homo neanderthalensis was a real species. Some scientists, like Gustav Albert Schwalbe, thought Neanderthals were a step between modern humans and apes. Others, like Marcellin Boule, believed Neanderthals were ape-like and unrelated to modern humans. Boule proposed two groups in Ice Age Europe: one leading to modern humans and another ending with Neanderthals. As research shifted to East Asia in the 1930s and 1940s (with finds like Java Man and Peking Man), the idea of a "Neanderthal phase" in human evolution was revisited.
In the 1970s, new methods called cladistics changed how scientists classified species. This led to the idea that Neanderthals in Africa and East Asia were not closely related to European Neanderthals. The "Out of Asia" theory was replaced by the "Out of Africa" theory, which said all modern humans share a recent common ancestor. Two theories emerged: modern humans replaced other humans, or they interbred with them. In 2010, genetic studies showed Neanderthals and modern humans interbred. Later studies continue to debate how Neanderthals should be classified.
Neanderthals are classified as a unique species, Homo neanderthalensis. Some scientists argue Neanderthals should be included in Homo sapiens (modern humans), but others say genetic differences and hybrid incompatibility support keeping them separate. The term "species" is still debated in science.
Neanderthals are most closely related to Denisovans, a mysterious group of humans known only through DNA. Neanderthal DNA is more similar to modern humans than to Denisovans in some genetic markers, like mitochondrial DNA and the Y-chromosome. Fossils from Sima de los Huesos, dating to 430,000 years ago, share Neanderthal nuclear DNA but have Denisovan-like mitochondrial DNA.
A 2021 study used dating methods to analyze the relationships between Middle Pleistocene and Neanderthal fossils. One example was La Chapelle-aux-Saints 1.
Evolution
Neanderthal skull features first appear in European fossils from the early Middle Pleistocene, often found in remains classified as Homo heidelbergensis. These early groups, sometimes called "pre-Neanderthals," slowly developed Neanderthal traits ("Neanderthalization") as they adapted to cold climates, evolving a body type suited for extremely cold environments. People living in cold regions today, like the Inuit, are sometimes studied as modern examples of these adaptations. During ice ages, populations may have been forced into small areas called refugia, which reduced genetic diversity and led to other Neanderthal traits through genetic changes. The 120,000- to 140,000-year-old Nesher Ramla fossils in Israel may represent a group that later repopulated Europe after the Penultimate Glacial Period.
Neanderthal traits varied widely even within the same population during the Middle Pleistocene. The process of Neanderthalization may have been slowed by gene flow between Western Europe and Africa, as seen in unusual fossils like Ceprano Man, which lack typical Neanderthal features. The first clear "early Neanderthals" appear in the fossil record near the end of Marine Isotope Stage 7 (about 243,000 years ago) and become the "classic" or "late Neanderthals" by the end of Marine Isotope Stage 5e. This timeline covers the Penultimate Glacial Period to the Last Interglacial. Some early Neanderthal teeth from Payré, France, may date to Marine Isotope Stage 8, but the dates are uncertain.
Genetic evidence suggests Neanderthals separated from modern humans during the early Middle Pleistocene. Neanderthals and Denisovans are more closely related to each other than to modern humans, meaning their split happened later. Before this split, Neanderthals and Denisovans (called "Neandersovans") migrating from Africa into Europe may have interbred with an earlier human group called "superarchaics," who had arrived in Europe around 1.9 million years ago.
Genetic data shows that Neanderthals, after 100,000 years ago, had small populations with low genetic diversity. This weakened natural selection and increased harmful mutations. It is unclear how long European Neanderthal populations faced this stress or how much it influenced the development of Neanderthal traits.
Demographics
The Neanderthals were the first human species to live in Europe for a long time. Early Neanderthals are mostly found in Western Europe, but later Neanderthals lived across Europe, as well as in Southwest and Central Asia, even near the Altai Mountains in southern Siberia. Early Neanderthals seem to have lived mainly in France, Spain, and Italy. Some groups moved temporarily eastward but stayed within Europe. However, southwestern France has the most Neanderthal sites.
The farthest south Neanderthals lived was at Shuqba Cave in the Levant. Earlier reports of Neanderthals in North Africa’s Jebel Irhoud and Haua Fteah were later found to belong to Homo sapiens. The farthest east Neanderthals lived was at Denisova Cave in Siberia (85°E). A skull from Maba Man in southeast China shares some physical traits with Neanderthals, but these traits may have developed separately rather than Neanderthals living in that area. The farthest north Neanderthals lived was around 55°N, with clear evidence found between 50°N and 53°N. However, glacial ice often destroyed human remains, making it hard to confirm. Middle Palaeolithic tools have been found as far north as 60°N in Russia, but these are more likely from modern humans.
Neanderthal living areas likely changed as ice sheets moved. They avoided frozen areas and lived in safer zones during cold periods. Areas with mild yearly temperatures were probably best for Neanderthals.
Like modern humans, Neanderthals likely came from a small group with an effective population size of about 3,000 to 12,000 people. They kept this small population, which meant harmful genes spread more easily because natural selection had less effect. Archaeological evidence suggests the first Cro-Magnon population was about 10 times larger than Neanderthals.
Compared to Cro-Magnons, Neanderthals may have had fewer people due to lower birth rates or higher infant deaths. In a study of 206 Neanderthals, about 80% of those over 20 years old died before age 40. This high death rate was likely because of their difficult environment. Infant deaths were also very high, with about 43% of babies dying in northern Eurasia.
Anatomy
The Neanderthal skull has a flat and broad top, rounded brow ridges, wide eye sockets, a broad nose, and a face that extends forward from the skull. When viewed from the back, the skull has a "bomb-like" shape. There is a depression on the back of the skull below the inion, and a bony projection called an occipital bun at the back. Like other early humans, Neanderthals did not have a true chin on their jaws.
The average Neanderthal braincase size was 1,640 cm³ for males and 1,460 cm³ for females, which is much larger than the average for modern humans. The largest known Neanderthal brain, Amud 1, measured 1,736 cm³, one of the largest brains ever recorded in humans. Neanderthal brain structure differed in areas linked to thinking and language, which may explain differences in behavior compared to Cro-Magnons in the archaeological record.
Neanderthals had large, wide noses, likely an adaptation to warm more cold air for their high metabolism and activity levels. However, their smaller olfactory bulbs suggest they may have had a less developed sense of smell and memory compared to modern humans.
Their cheekbones were strong, front teeth were large and shovel-shaped, molars had swollen tooth pulp (taurodontism), and there was a gap behind the molars (retromolar space). These traits are thought to result from heavy use of front teeth for processing tough foods or using the mouth as a tool.
Though often imagined as short and stocky, Neanderthals were on average the same height as pre-industrial Europeans or slightly taller. Their body mass index was similar to that of 20th-century Canadians and Americans. Neanderthal body size varied by region, with West Asian Neanderthals being taller and more slender than European Neanderthals.
In a sample of 45 long bones from 14 men and 7 women, the average height was 164–168 cm (5 ft 5 in to 5 ft 6 in) for males and 152–156 cm (5 ft 0 in to 5 ft 1 in) for females. Adult Neanderthals ranged in height from about 147.5 to 177 cm (4 ft 10 in to 5 ft 10 in). The average male body mass index was 26.9–28.3.
Neanderthal pelvic bones were extremely wide, with male hips about 31% wider than modern human males. Unlike modern humans, Neanderthals showed no sexual dimorphism in their pelvis; both males and females had large pelvic bones relative to their body size, with larger males having the largest pelvises.
Neanderthals had deep and wide chests with large thoracic cavities, possibly allowing for stronger lung function. They had more fast-twitch muscle fibers and higher caloric needs. Their limbs were proportionally short, a trait linked to "hyper-arctic" adaptations. Neanderthals may have been efficient sprinters due to strong lungs, fast-twitch muscles, and shorter limbs.
Neanderthal pigmentation genes in modern non-African people are linked to both lighter and darker skin and hair tones, suggesting Neanderthals may have had varied pigmentation. Some Neanderthals had genes for red hair, but this was not common. These traits were beneficial for modern humans in Eurasia, where sunlight is less intense than in Africa.
Neanderthals had a high rate of traumatic injury, with 79–94% of remains showing healed major injuries. About 37–52% had severe injuries, and 13–19% were injured before adulthood. One example, Shanidar 1, had a missing right arm, a bone infection, vision problems, and possible hearing loss. This high injury rate may result from dangerous hunting practices or frequent animal attacks.
Low population numbers led to low genetic diversity and likely inbreeding, reducing the ability to eliminate harmful mutations. It is unclear how this affected individual Neanderthals or if it caused more birth defects than in modern humans.
Culture
It is hard to know exactly how many Neanderthals lived in each group, but clues from other sources suggest small groups of 10 to 30 people. These groups likely moved between caves depending on the season, as shown by remains of seasonal items, like certain foods. They returned to the same places again and again. Some sites were used for over 100 years. Neanderthals might have been competing with cave bears for cave space. Groups may have been mainly patrilocal, meaning men stayed in their home area and women joined from other groups for breeding.
Neanderthals had a small population across their range, which may have made it hard for them to trade over long distances or avoid inbreeding. They likely interacted often with nearby communities but not as much with groups farther away. Genetic studies show there were at least three main groups: Western Europe, the Mediterranean coast, and east of the Caucasus, with some movement between these areas.
While Cro-Magnons are often thought to have divided tasks by gender, like men hunting and women gathering, it is unclear if Neanderthals did the same. Both Neanderthal men and women had similar injuries, which might mean both hunted. Their teeth showed patterns that could mean men and women carried different items in their mouths, though these items might not have been used for food. At El Sidrón Cave in Spain, women may have eaten more seeds and nuts than men. The lack of specialized tasks in Neanderthals is often linked to their small population and group size, which may have made it hard to develop complex roles or tools.
Once thought to be scavengers, Neanderthals are now considered top predators. They mainly ate what was available nearby, so their diet varied widely across their range. For example, Neanderthals in forests ate about the same amount of plants as Cro-Magnons, but Neanderthals on open steppe (where plants are scarce) ate far fewer plants.
In many European sites, Neanderthals hunted red deer, reindeer, horse, aurochs, ibex, and steppe bison. In Southwest Asia, they hunted mountain gazelle, Persian fallow deer, wild goats, and camels. They may have hunted large animals like woolly mammoths and rhinoceroses less often if those animals were not nearby. At the 125,000-year-old Neumark-Nord site in Germany, there is evidence of Neanderthals hunting straight-tusked elephants regularly, about every 5 to 6 years. Some groups ate fish and shellfish, like dolphins and seals at Vanguard Cave in Gibraltar. They also hunted small animals, such as rabbits and tortoises, and ate many bird species, including quail and larks. Neanderthals consumed a variety of plants and mushrooms, with over 50 species found at Kebara Cave in Israel.
Neanderthals may have used many ways to prepare food. At Cueva del Sidrón in Spain, they may have roasted and smoked meat, and used plants like yarrow and chamomile for flavor or medicine. At Gorham’s Cave in Gibraltar, they roasted pinecones to get pine nuts, and at Gruta da Figueira Brava, they softened crab shells before eating them. At Grotte du Lazaret in France, Neanderthals hunted 23 deer, 6 ibex, 3 aurochs, and 1 roe deer during a single autumn season, possibly to store meat for winter. At Neumark-Nord, they may have used animal fat to reduce the effects of too much protein. Calcium evidence shows Neanderthals at Grotte du Bison often ate bones.
Neanderthals competed with large carnivores but also hunted some, like cave lions, wolves, and bears, even during hibernation. They sometimes avoided competition by hunting different prey than hyenas and wolves. However, Neanderthals were often attacked by animals.
There are examples of Neanderthals eating other Neanderthals, but this may have only happened during extreme food shortages, like in some human history.
Neanderthals collected unusual objects, like shells, fossils, and gems. It is unclear if these were for beauty or had symbolic meaning. Some shells were painted, and researchers suggest Neanderthals used bird feathers as art materials. A 2020 study found a 3-ply cord made from tree fibers at Abri du Maras in France, which could be used for stringing beads. Perforated shells from Cueva Antón in Spain, dating to 115,000 years ago, may have been used as necklaces.
There are many simple carvings and scratches on stones, bones, and pebbles. As of 2014, 63 carvings have been found at 27 sites across Europe and the Middle East. It is debated whether these had symbolic meaning. Neanderthals may have made finger flutings on cave walls at La Roche-Cotard over 57,000 years ago.
Neanderthals used ochre, a red clay pigment. It is unclear if this was for art, as modern humans used ochre for decoration, medicine, and other purposes.
The 43,000-year-old Divje Babe flute, made from a cave bear bone in Slovenia, is sometimes linked to Neanderthals, but many scientists believe it was made by an animal chewing the bone.
Neanderthals made stone tools associated with the Mousterian industry, especially using the Levallois technique. After developing this from the Acheulean industry, their tool-making progress stopped for 150,000 years. This lack of innovation may have been due to their small population, which limited the spread of new ideas. Neanderthals usually used materials from nearby sources, within 5 km. Some groups made tools from shells and bones. They may have attached spear tips to spears using birch bark tar. European Neanderthals also made wooden spears, like the 400,000-year-old Clacton Spear in Britain and the 300,000-year-old Schönin spear in Germany.
Interbreeding
The first Neanderthal genome sequence was published in 2010, and it showed that Neanderthals and early modern humans likely interbred. Neanderthal genes in modern humans come from at least two interbreeding events that happened outside of Africa: one around 250,000 years ago and another between 40,000 and 54,000 years ago. Interbreeding also occurred in other groups that are not related to any living people today. People with ancestors outside of sub-Saharan Africa may have about 2% Neanderthal DNA in their genes. Sub-Saharan Africans may also have Neanderthal DNA, which likely came from Neanderthals who migrated back to Africa. In total, about 20% of the Neanderthal genome is found in modern humans. Most of this DNA comes from children born to modern human mothers and Neanderthal fathers. Many Neanderthal genes were likely removed from the human gene pool over time because they carried harmful changes. Much of the remaining Neanderthal DNA does not have clear biological functions, but some genes may help with metabolism, brain activity, and body development. Some genes might have helped early humans adapt more quickly to new environments, such as those related to the immune system.
Genetic studies suggest that interbreeding mostly happened between Neanderthal males and modern human females. This is supported by the lack of Neanderthal mitochondrial DNA and the lower amount of Neanderthal DNA on the X chromosome in modern humans. According to Svante Pääbo, it is unclear whether modern humans were socially dominant over Neanderthals, which might explain why interbreeding was more common between Neanderthal males and modern human females. A 2026 study confirmed that sexual selection, or a preference for Neanderthal males and modern human females, was the main reason for the unequal mating patterns, not differences in population size or migration.
Neanderthals in the Siberian Altai Mountains interbred with Denisovans, a related group. About 17% of the DNA in one Denisovan individual came from Neanderthals. Before genetic evidence confirmed this, scientists like Thomas Huxley, Hans Peder Steensby, and Coon suggested that Neanderthals and early humans might have interbred. In the early 2000s, fossils such as Lagar Velho 1 and Muierii 1 were found, which some thought might be hybrids. However, modern scientists note that some similar physical traits could have developed independently due to environmental adaptations, not just interbreeding.
Extinction
The extinction of Neanderthals was part of a larger event during the Late Pleistocene, when many large animals disappeared. Neanderthals were replaced by modern humans, as shown by the change in stone tool technology across Europe. Middle Palaeolithic Mousterian tools were nearly completely replaced by Upper Palaeolithic Aurignacian tools between 39,000 and 41,000 years ago. In some areas of Spain, such as Catalonia and Aragón, Mousterian tools may have lasted until about 39,000 years ago. In southern Spain and Gibraltar, Mousterian tools might have been used as late as 32,000 to 35,000 years ago. Similar areas where Neanderthals may have survived longer have been suggested in other parts of Europe, such as Italy, the Balkans, and Crimea.
Historically, some people believed that modern humans caused the extinction of Neanderthals and other early humans by taking over their lands and resources. This view was often tied to ideas of superiority, where modern humans were seen as more advanced than Neanderthals.
In general, the extinction of Neanderthals is often explained by competition with modern humans. Modern humans may have had advantages, such as larger populations, better movement across long distances, and more advanced tools and survival methods. Some Neanderthal groups may have been absorbed into modern human groups through interbreeding, rather than being outcompeted. Evidence for this includes the discovery of Neanderthal DNA in modern humans. In some regions, such as central France and northern Spain, Neanderthals may have adopted tools and techniques used by modern humans. Similar changes in tools have been found in Italy and Central Europe.
Some scientists also suggest that Neanderthals had smaller populations, which may have led to genetic problems that made them less able to adapt to environmental changes or new diseases brought by modern humans. It is unclear how much climate changes, such as those during Heinrich Event 4 or the Campanian Ignimbrite eruption, affected Neanderthals, as they had survived previous ice ages in Europe. If climate changes or disasters caused Neanderthals to leave certain areas, modern humans may have been better at returning to those places. The Laschamp event, which occurred between 39,000 and 42,000 years ago, may have increased harmful ultraviolet radiation. Neanderthals may have been more vulnerable to this because they did not wear protective clothing as effectively as modern humans, and they may not have used ochre (a red mineral) as sunscreen in the same way.
In popular culture
Neanderthals have been shown in popular culture, including books, movies, and comedy. The "caveman" image often makes fun of Neanderthals, showing them as simple, hunchbacked, dragging their knuckles, swinging clubs, grunting, and acting without social skills, driven only by basic instincts. The word "Neanderthal" is sometimes used as a way to insult someone.
In books, Neanderthals are sometimes shown as violent or scary, as in H. G. Wells' The Grisly Folk and Elizabeth Marshall Thomas' The Animal Wife. However, some books show them with a culture that is advanced but different, such as in William Golding's The Inheritors, Björn Kurtén's Dance of the Tiger, and Jean M. Auel's Clan of the Cave Bear and her Earth's Children series.
References
- After being mined for limestone , the cave caved in and was lost by 1900. It was rediscovered in 1997 by archaeologists Ralf Schmitz and Jürgen Thissen . [ 9 ]
- The German /t/ phoneme was frequently spelled th from the 15th to 19th centuries until the German Orthographic Conference of 1901 . The German spelling Thal ("valley", a cognate of English dale ) changed to Tal , and the h was also dropped from Neandertal for the valley and Neandertaler for the species. [ 10 ]
- In Mettmann , "Neander Valley", there is a local idiosyncrasy in use of the outdated spellings with th , such as with the Neanderthal Museum (but the name is in English [German would require Neandertalermuseum ]), the Neanderthal station (Bahnhof Neanderthal), and some other rare occasions meant for tourists. Beyond these, city convention is to use th when referring to the species. [ 10 ]
- King made a typo and wrote "theositic".
- The bones were discovered by workers of Wilhelm Beckershoff and Friedrich Wilhelm Pieper . Initially, the workers threw the bones out as debris, but Beckershoff then told them to store the bones. Pieper asked Fuhlrott to come up to the cave and investigate the bones, which Beckershoff and Pieper believed belonged to a cave bear . [ 9 ]
- The X-chromosome carries far less archaic DNA than any autosome , which has either been explained as hybrid incompatibility (the large-X effect — background selection ) or male sex bias (hybrids were normally the children of a male Neanderthal and female modern human). [ 37 ]