Why did Neanderthals have short legs?

Short legs may have allowed Neanderthals to move over mountainous terrain more efficiently.

ScienceDaily — While most studies have concluded that a cold climate led to the short lower legs typical of Neandertals, researchers at Johns Hopkins have found that lower leg lengths shorter than the typical modern human's let them move more efficiently over the mountainous terrain where they lived. The findings reveal a broader trend relating shorter lower leg length to mountainous environments that may help explain the limb proportions of many different animals.

Their research was published online in the American Journal of Physical Anthropology and will appear in print in the November issue.

"Studies looking at limb length have always concluded that a shorter limb, including in Neandertals, leads to less efficiency of movement, because they had to take more steps to go a given distance," says lead author Ryan Higgins, graduate student in the Johns Hopkins Center of Functional Anatomy and Evolution. "But the other studies only looked at flat land. Our study suggests that the Neandertals' steps were not less efficient than modern humans in the sloped, mountainous environment where they lived."

Neandertals, who lived from 40,000 to 200,000 years ago in Europe and Western Asia, mostly during very cold periods, had a smaller stature and shorter lower leg lengths than modern humans. Because mammals in cold areas tend to be more compact, with a smaller surface area, scientists have normally concluded that it was the region's temperature that led to their truncated limbs compared to those of modern humans, who lived in a warmer environment overall.