Why Neanderthals Were Shorter, Stockier and Stronger Than Us

We modern humans like to think of ourselves as superior to our extinct hominin relatives. When it comes to strength, however, Neanderthals had us beat. “They had both larger muscles and greater leverage for those muscles,” says Steven E. Churchill, a human paleontologist at Duke University and author of the book, Thin on the Ground: Neandertal Biology, Archeology, and Ecology. Their brawny physiques helped Neanderthals survive the inhospitable climate of Ice Age-era Eurasia—that is, until Homo sapiens arrived on the scene.

Since the 1800s, skeletal remains from hundreds of individual Neanderthals have been recovered. Yet, many consist of only a “single bone or single tooth,” says Bence Viola, a paleoanthropologist at the University of Toronto. He notes that very few Neanderthal remains are complete enough to estimate stature and body mass and that females are especially underrepresented.

Nonetheless, by analyzing their bones, scientists have been able to determine that Neanderthals were conspicuously more robust than modern humans. “They’re just incredibly jacked. They’re very, very muscular relative to their size,” says Libby W. Cowgill, a biological anthropologist at the University of Missouri and co-editor of the book, Neandertal Skeletal Anatomy: Form, Function and Paleobiology. “You would not want to take on a Neanderthal in a wrestling match.”

Neanderthals’ right arms were particularly massive, up to 50 percent bigger than their left arms. “The only modern humans that come anywhere close to that [level of asymmetry] are professional tennis players,” Cowgill says. Neanderthals might have also had a wider range of motion in their forearms and thumbs than modern humans (and possibly at other joints as well).

Being stockier and shorter, with shorter limbs, helped Neanderthals retain heat, an advantage throughout their range in Europe and western Asia. “If you’re in a cold climate, you want to minimize the amount of skin that heat can escape from,” says Cowgill, adding that modern humans from Arctic regions evolved similar body types.

The cold was likely just one reason for Neanderthals’ broad builds. Churchill and a co-author argue in a paper that their superior strength was “not a passive by-product of selection for thermoregulatory competence,” but rather necessary for “subduing and butchering large prey; breaking branches and saplings for firewood or woodworking; scraping hides and planing wood.” Neanderthals hunted some of the largest mammals of the Ice Age, including elephants weighing more than 10 tons, though they apparently spent more time on domestic chores than thrusting spears.

Ice Age Homo sapiens likewise hunted large mammals and were also no slouches in the strength department. As Viola notes, they were typically stronger than their present-day counterparts, even if they lacked the muscle definition of hardcore weightlifters. “We are sedentary today, most of us anyway, and so we are much less strong,” Viola says. “It’s not necessarily just pure strength, it’s endurance and conditioning.”

In addition to their sturdy builds, Neanderthals had several other features that differentiate them from modern humans. They had more prominent brow ridges, for example, along with wider noses, swept-back cheekbones, occipital buns at the back of their skulls and no chins.

Even so, they closely resembled modern humans, as demonstrated by a display at the Neanderthal Museum in Germany, in which a Neanderthal model poses in a tailored suit. “If you saw this guy on the subway, you might think he’s robust, that he’s a tough guy, but you would recognize him as human,” Viola says.

A June 2026 paper found fetal development to be similar among Neanderthals and modern humans. As adults, meanwhile, there was clearly interbreeding between the groups, with recent genetic research suggesting that matings occurred more often between male Neanderthals and female Homo sapiens than the reverse. (Neanderthals and modern humans also mated with Denisovans, a third group of prehistoric hominins.) Today, most people with ancestry outside Africa carry about 1 percent to 2 percent Neanderthal ancestry in their genomes.

In fact, some people can thank their Neanderthal ancestors for a portion of their strength. In an August 2026 paper published in the journal Current Biology, a team of scientists identified Neanderthal-specific DNA related to the so-called growth hormone receptor. Cells engineered to carry this Neanderthal receptor were found to grow faster in a laboratory than nonmodified cells.

Moreover, present-day humans with the Neanderthal receptor—which includes roughly 20 percent of South Asians, 15 percent of East Asians and 0.5 percent of Europeans—were found to have 0.6 pounds more muscle mass and be 0.1 inches taller on average than noncarriers. (As the paper points out, this effect on muscle mass and height is minor compared with other genetic, environmental and cultural factors.)

Passed-down Neanderthal DNA has similarly shaped traits such as immune systems and skin and hair color. “They live on in us,” says Hugo Zeberg, a geneticist at the Karolinska Institute in Sweden who was a senior author of the Current Biology paper. “In a way, they never disappeared.”

Their rippling muscles aside, Neanderthals had brains that were, on average, slightly larger than those of modern humans. Just like us, they used tools, wore clothes, controlled fire, created art and even practiced a primitive form of dentistry. So why did Neanderthals vanish, whereas modern humans thrived?

As with the extinction of Ice Age megafauna, various theories have been put forward—none mutually exclusive—including that modern humans killed Neanderthals in violent encounters, introduced diseases to which they had little immunity, outcompeted them for resources or gradually absorbed them through interbreeding. A major period of interbreeding between modern humans and Neanderthals occurred roughly 45,000 to 50,000 years ago. Climate change might have played a role as well.

No one knows for sure, but the fact that Neanderthals lived in small and isolated groups likely played a role. With perhaps a few exceptions, “it’s not a healthy gene pool,” Viola says. “It’s European royal family style, and that’s not good for you long term.” Modern humans, on the other hand, seemingly outnumbered Neanderthals, formed larger and more complex social networks that reduced inbreeding and might have had a technological edge. “We were more numerous, they were a bit stronger,” Zeberg says.

Although we survived and they didn’t, Zeberg cautions against underestimating them. “Neanderthals lived longer in Eurasia than we have done so far,” he says. “They were quite successful for hundreds of thousands of years.”