If the image that jumps to mind when you think “Neanderthal” is a hunched-over cave dweller with a barrel-like chest, you may need to think again.
An international team of scientists has upended that stereotype by creating a 3-D virtual reconstruction of the chest of a 60,000-year-old male Neanderthal skeleton. As it turns out, not only did these ancient early humans stand upright, with straight spines—they also had similar-size chests, but greater lung capacity, than humans today.
Scientists have long wondered about the shape of Neanderthals’ chests, and how exactly they took in the greater amounts of oxygen necessary to power their heavier bodies through the harsh conditions of the last Ice Age. Neanderthals went extinct about 40,000 years ago—although not before interbreeding with early Homo sapiens, or modern humans.
Researchers from Spain, Israel and the United States conducted the new study, using the most complete Neanderthal (also spelled Neandertal) skeleton unearthed to date. Known as Kebara 2, or “Moshe” for short, the skeleton was found in the early 1980s in northern Israel. In an earlier study, the same team created a virtual model of Moshe’s spine.
The new study, published in the journal Nature Communications, focused on the thorax, the area of the body containing the ribcage and upper spine. After making a CT scan of each vertebra and every individual rib fragment, the researchers virtually reassembled them to create the 3D model.
"The shape of the thorax is key to understanding how Neanderthals moved in their environment because it informs us about their breathing and balance," Asier Gomez-Olivencia of the University of the Basque Country in Spain, the study's lead author, said in a press release.
Many Neanderthal remains have been found at sites in Europe, Asia and the Middle East, but “ribs and vertebrae are fragile and have a limited fossil record,” Gomez-Olivencia told New Scientist. To fill this gap, scientists had suggested Neanderthals must have had bigger chests than modern humans, in order to hold larger lungs.
But with their virtual reconstruction of the Kebara-2 thorax, Gomez-Olivencia and his fellow researchers found that the Neanderthal’s chest and lungs probably weren’t any larger than those of modern humans. Instead, they were shaped differently: The Neanderthal thorax was wider at the bottom, meaning he could have had a wider, larger diaphragm and been able to suck in more air than we can.
"The wide lower thorax of Neanderthals and the horizontal orientation of the ribs suggest that Neanderthals relied more on their diaphragm for breathing," study co-author Ella Been of Ono Academic College explained in the press release. "Modern humans, on the other hand, rely both on the diaphragm and on the expansion of the rib cage for breathing.”
Though the researchers still don’t know if this lung capacity adaptation helped Neanderthals survive climate change or not, they’re hoping that using more of these virtual reconstruction techniques can continue to shed light on how exactly our ancient human ancestors moved around and interacted with the world.