3-D model of Neanderthal rib cage busts myth of ‘hunched-over cavemen’
High-tech visualization techniques on Israeli skeleton give new window into lives of our early human cousins, who survived extreme conditions but went extinct some 30,000 years ago
Deputy Editor Amanda Borschel-Dan is the host of The Times of Israel's Daily Briefing and What Matters Now podcasts and heads up The Times of Israel's Jewish World and Archaeology coverage.
Neanderthals walked upright, had spines straighter than those of modern man, would have been strong and sturdy, and breathed deeply from their bell-, not barrel-shaped ribcages, according to a recently published article written by an international team of scientists.
Busting open the myth of the arm-dragging, hunched-over caveman, the scientists, based at universities in Israel, Spain, and the United States, drew their conclusions from a recently completed 3D virtual reconstruction of the ribcage of the Kebara 2 skeleton — aka “Moshe” — the headless but almost complete Neanderthal remains unearthed in 1983 in a northern Israel cave.
It turns out from the first ever reconstruction of the thorax of an early hominid that before his death at age 32 some 59,000-64,000 years ago, the 170-centimeter tall, 75 kilogram (5 foot 7, 165 pound) Moshe would have had great posture as he breathed deeply from his diaphragm.
Scientists believe Neanderthals roamed the earth from Western Europe to Central Asia about 400,000 years ago. These hunter-gatherers were often cave-dwellers, who managed to reproduce with early Homo sapiens — and survived extreme conditions including ice ages — before going extinct some 30,000 years ago.
This new study aims to give a more accurate look at Neanderthal physique and movement than any other before it.
Written by a team including University of the Basque Country’s Asier Gómez-Olivencia, Bar Ilan University’s Alon Barash, and Ono Academic College’s Ella Been, the study, “3D virtual reconstruction of the Kebara 2 Neandertal thorax” was published in the October 30, 2018, edition of the peer-reviewed journal Nature Communications.
Been, a clinical physical therapist as well as a paleo-anthropologist, spoke with The Times of Israel this week about the study and its significance to modern medical practitioners such as herself.
Been said she began to work on paleo-anatomy some 20 years ago when she commenced her graduate degrees at Tel Aviv University, where the Kebara 2 skeleton is located. She was looking for a research topic outside of clinical physical therapy and chose to investigate Kebara 2 and, initially, his spine.
“It’s very convenient to have the best preserved Neanderthal handy,” joked Been in a phone conversation shortly after teaching a class at Ono Academic College this week. “Not much had been done with the spine about 20 years ago.”
Two years ago, her work on Kebara 2’s spine bore fruit when she and her colleagues published a virtual reconstruction of the Kebara 2 spine as a way of investigating Neanderthal biomechanics. The research and methodology for their paper, “3D Reconstruction of Spinal Posture of the Kebara 2 Neanderthal,” included medical CT scans of vertebrae, ribs and pelvic bones, along with the development of special 3D software. The Human Paleontology and Prehistory publication laid the groundwork for the recent reconstruction of the ribcage.
What is striking in the new study is its geometric morphometric analysis — basically a comparison between the reconstructed structure and skeletons of modern man.
The 3-D model of the Neanderthal rib cage compared with that of modern man “made us realize things we couldn’t see or measure before,” said Been.
Visually, one clearly sees how the Neanderthal rib cage was broader at its base, with horizontal ribs, versus modern man’s angled ribs. Likewise, one can see that the spine is attached more deeply inside the thorax than modern man’s is.
The creation of the model required “meticulous work,” said Bar Ilan University’s Barash in a press release on the new research. “We had to CT scan each vertebra and all of the ribs fragments individually and then reassemble them in 3D.”
“Reconstructing the thorax was an exercise in starting from scratch, deliberately trying to avoid being influenced by past theories of how Neanderthals looked or lived,” Barash said.
One such theory was that of a barrel-chested, somewhat gorilla-looking caveman. The new thorax reconstruction finds that while the bottom of the Neanderthal ribcage was broader, the total volume of lung capacity was roughly equivalent to modern man’s. The authors write, “we hypothesize that Neanderthals may have had a somewhat different breathing mechanism, one which relied relatively more on diaphragm contraction, than is exhibited in modern humans.”
Physical therapist Been explains how the anatomical structure of Kebara 2’s ribcage would have indicated a different way of breathing. The diaphragm, which attaches to the ends of the wide lower ribs, would have been larger than that of modern man, she said.
“If the ribs are larger, then the diaphragm is larger and potentially it could be more efficient for breathing than that of modern humans,” said Been.
At the same time, Neanderthal ribs are horizontal, as opposed to modern man’s, which are angled down and allow for more expansion upwards in what is called a “bucket handle” system of breathing: When raising the bucket handle there is more volume, versus when it is at rest next to the bucket basin. Neanderthals, which didn’t have the option of expanding their rib cage upwards, must have been more reliant on their large diaphragms, said Been.
Based on her previous study, Been said Neanderthals had even straighter spines than modern humans. “Our spine has the shape of an S, whereas Neanderthals had a small s,” she said.
Additionally, the whole spine is deeper into the rib cage than modern humans’s is, which would give the Neanderthals more stability.
“The stable spine gave good equilibrium,” she said. Based on the reconstruction and comparisons with other known Neanderthal fossil remains, the Neanderthals would likely have been less flexible than modern man, but would have had stronger upper limbs and a lot of trunk stability on their relatively shorter lower limbs. It is a body built for strong arm movements and carrying heavy loads, she said.
Although they would likely have been less prone to falling, Been said, their straighter spines could have meant, however, that their bodies had less shock absorption. “They couldn’t do high impact activity on their feet,” she said, which meant that their running and jumping skills would have been less good than their more light-footed, agile modern human cousins.
One thing is clear: The Neanderthals were not hunched over. “On the contrary,” said Been. They had straight spines, and stood with their heads above their pelvis, not leaning forward.
Because the 3-D model is based only on one Neanderthal skeleton, the team intends to do similar reconstructions with other fragmented skeletons from France, Iraq, and elsewhere.
“It will give us a better understanding on the variation within Neanderthals,” said Been, who added she is “pretty sure the other Neanderthals will look much like Kebara,” since they have the same morphology.
For Been, a physical therapist, there is added practical value in her hypothetical research.
“I think that understanding where we come from gives us perspective for who we are. In the medical field we often have to think of things in one way, ‘normal and abnormal.’ We forget to look at diversity,” she said.
Studying Neanderthals — “successful humans who walked on two legs, breathed differently, and lived for hundreds of thousands of years” — could allow medical practitioners more space for increased acceptance of variations within the population.
“Maybe instead of deciding confidently what is normal or abnormal, if it’s not a pathological problem, we can understand the variation before saying what it is,” Been said. From studying the Neanderthals, she has realized in her own work that “different variations can be successful in many ways.”
