Neanderthal anatomy

Neanderthal anatomy is characterised by a long, flat skull and a stocky body plan. When first discovered, Neanderthals were thought to be anatomically comparable to Aboriginal Australians, in accord with historical race concepts. As more fossils were discovered in the early 20th century, French palaeontologist Marcellin Boule defined them as a slouching, apelike species; a popular image until the middle of the century. Neanderthal features gradually accreted in European populations over the Middle Pleistocene, driven by natural selection in a cold climate, as well as genetic drift when populations crashed during glacial periods. This culminated in the "classical Neanderthal" anatomy by the Last Interglacial.

The Neanderthal skull is distinctive by namely a rounded supraorbital torus (brow ridge), large orbits (eye sockets) and nose, and an occipital bun at the back of the skull. The jaws and teeth are strong, which may have been a response to habitual heavy loading of the front teeth. The body is typically short and stocky, with an average size of 165 cm (5 ft 5 in) and 78 kg (172 lb) for males, and 155 cm (5 ft 1 in) and 66 kg (146 lb) for females. Short limbs may be an adaptation to the cold climate (Allen's rule) or to improve sprinting efficiency.

The brain is large, averaging 1,640 cc (100 cu in) in males and 1,460 cc (89 cu in) in females, larger than the average of any living population. The Neanderthal brain was organised much differently than the modern human brain, especially in regions related to cognition and language, which may be implicated in Neanderthal behaviour and the poorer evidence of material culture compared to Cro-Magnons.

Neanderthals may have had developed mesopic vision in low-light conditions, and a stronger respiratory system to fuel a comparatively faster metabolism. It is unclear if Neanderthals could produce speech at the same level as modern humans. Neanderthal skin and hair colour may have ranged from dark to light. Red hair seems to have been a rare trait. Neanderthals may have had a faster growth rate than modern humans. Neanderthals suffered extensively from traumatic injury and major physical trauma, possibly as a consequence of risky hunting strategies and animal attacks. They also maintained a low population and genetic diversity, leading to inbreeding depression.