The Neanderthals or Neandertals are an extinct species of human in the genus Homo, possibly a subspecies of Homo sapiens. They are very closely related to modern humans, differing in DNA by only 0.15%. Remains left by Neanderthals include bones and stone tools, which are found in Eurasia, from Western Europe to Central and Northern Asia. The species is named after Neandertal (“Neander Valley”), the location in Germany where it was first discovered.
Neanderthals are generally classified by palaeontologists as the species Homo neanderthalensis, but a minority consider them to be a subspecies of Homo sapiens (Homo sapiens neanderthalensis). The first humans with proto-Neanderthal traits are believed to have existed in Europe as early as 600,000–350,000 years ago.
The exact date of their extinction is disputed. Fossils found in the Vindija Cave in Croatia have been dated to between 33,000 and 32,000 years old, and Neanderthal artifacts from Gorham’s Cave in Gibraltar are believed to be less than 30,000 years old, but a recent study has redated fossils at two Spanish sites as 45,000 years old, 10,000 years older than previously thought, and may cast doubt on recent datings of other sites. Cro-Magnon (Eurasian Early Modern Human) skeletal remains showing some “Neanderthal traits” have been found in Lagar Velho in Portugal and dated to 24,500 years ago, and in Cioclovina in Romania dated to 35,000 years ago, suggesting that there may have been an extensive admixture of the Cro-Magnon and Neanderthal populations throughout Europe.
Several cultural assemblages have been linked to the Neanderthals in Europe. The earliest, the Mousterian stone tool culture, dates to about 300,000 years ago. Late Mousterian artifacts were found in Gorham’s Cave on the south-facing coast of Gibraltar. Other tool cultures associated with the Neanderthals include the Châtelperronian, the Aurignacian, and the Gravettian; their tool assemblages appear to have developed gradually within their populations, rather than being introduced by new population groups arriving in the region.
With an average cranial capacity of 1600 cc, Neanderthal’s cranial capacity is notably larger than the 1400 cc average for modern humans, indicating that their brain size was larger. However, due to larger body size, Neanderthals are less encephalized. In 2008, a group of scientists produced a study using three-dimensional computer-assisted reconstructions of Neanderthal infants based on fossils found in Russia and Syria. The study indicated that Neanderthal and modern human brains were the same size at birth, but by adulthood, the Neanderthal brain was larger than the modern human brain. They were much stronger than modern humans, having particularly strong arms and hands. Males stood 164–168 cm (65–66 in) and females about 152–156 cm (60–61 in) tall.
Genetic evidence published in 2010 suggests that Neanderthals contributed to the DNA of anatomically modern humans, probably through interbreeding between 80,000 and 30,000 years ago with a population of anatomically modern humans. According to the study, by the time that population began dispersing across Eurasia, Neanderthal genes constituted as much as 1–4% of its genome (roughly equivalent to having one Neanderthal great-great-great-grandparent). Ötzi the iceman, Europe’s oldest preserved mummy, was found to possess an even higher percentage of Neanderthal ancestry. Recent findings suggest there may be even more Neanderthal genes in non-African humans than previously expected, at about 20% of the human gene pool instead but an individual non-African genome is only 2% Neanderthal and still mostly Homo sapiens.
In December 2013, researchers reported evidence that Neanderthals practiced burial behavior and intentionally buried their dead. In addition, scientists reported, for the first time, the entire genome of a Neanderthal. The genome was extracted from the toe bone of a 130,000-year-old Neanderthal found in a Siberian cave.