Barefoot and Rugged: What Neanderthal Heels Say About Their Hard Lives

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A human heel looks unremarkable, just a stubby knob of bone that absorbs the shock of every step, day after day, for an entire lifetime. For Neanderthals, who spent their days tracking game across rocky, uneven ground with nothing but bare skin between foot and earth, that same bone carried a very different kind of load. A new analysis of ancient bones shows just how different: Neanderthal feet appear to have worked in a way unlike anything seen in modern humans.

Researchers scanned and digitally measured the heel bone, known as the calcaneus, from seven Neanderthal individuals and compared them to the same bone from 64 Homo sapiens spanning tens of thousands of years, from Ice Age hunter-gatherers to people buried in a 19th and 20th century Italian cemetery. Published in the Journal of Human Evolution, the analysis found Neanderthals had more than slightly bulkier bones than ours. Their feet appear to have functioned differently, favoring a more rolled-in posture than is typical in modern humans and built to help carry heavier loads over rough ground.

Foot shape is no small detail in the story of human evolution, because it reflects how a body actually moved through the world, how much weight it carried, and what kind of ground it covered. A heel bone shaped for stability on jagged terrain rather than smooth, fast strides says something specific about how Neanderthals lived. Comparing it to the heels of recent, shoe-wearing humans shows how much modern life has reshaped that same bone over thousands of years.

How Scientists Studied Neanderthal Heel Bones

Heel bones don’t come with a label explaining how their owners walked, so researchers had to reconstruct that information from shape alone. Using laser scanners and a high-resolution CT scanner, the same basic technology doctors use for medical imaging, but far more detailed, the team built 3D digital models of each heel bone. Onto every model, they placed a standardized set of reference points, nearly three hundred in total, marking specific ridges, curves, and surfaces that could be compared precisely across every individual in the study.

Seven Neanderthal heel bones came from well-known fossil sites in France, Spain, and Belgium, including La Chapelle, La Ferrassie, El Sidrón, and Spy, dated to roughly 70,000 to 36,000 years ago. For comparison, the Homo sapiens sample included hunter-gatherers from Israel dating back 120,000 to 90,000 years, more hunter-gatherers from the Czech Republic and Italy dated between about 31,000 and 12,000 years ago, Iron Age farmers and foragers from Sicily, and a group of 46 individuals from a documented skeletal collection in Bologna, Italy, dating to the 19th and 20th centuries. That last group represented the most sedentary, shoe-wearing population in the study.

Once the digital models were complete, researchers ran statistical comparisons to see how much shape variation aligned with species or lifestyle group rather than random individual differences. They examined the whole heel bone as well as specific working parts: the joint surfaces that connect to the ankle bone, the joint connecting to a small foot bone called the cuboid, and the back portion of the heel where the Achilles tendon attaches.

What Neanderthal Heel Bones Reveal About Their Walk

Shape differences between Neanderthals and Homo sapiens showed up clearly across nearly every part of the bone examined. Neanderthal heels were shorter front to back, wider side to side, and taller than those of any Homo sapiens group in the study, even though their overall bone size fell within the normal human range. That combination of proportions points toward a foot built to bear heavy loads and handle a lot of mechanical stress, rather than one built for an efficient, springy stride.

Shape of the back knob of the heel, where calf muscles attach via the Achilles tendon, accounted for the single biggest difference between Neanderthals and modern humans in the entire study. Neanderthals also had a shorter version of a groove near the ankle joint called the sinus tarsi, considered an older, ancestral feature rather than something unique to them. More telling, the joint surfaces connecting the heel to the ankle bone were flatter and wider in Neanderthals, closely resembling patterns earlier research linked to a habitually pronated, or rolled-inward, foot posture. A small bony knob that normally anchors a ligament supporting the arch of the foot was also noticeably reduced in Neanderthals compared with Homo sapiens. That reduction suggests their foot arch may have worked, and perhaps flexed, differently than the modern human arch does.

Not every Homo sapiens group looked the same, either. Early, highly mobile hunter-gatherer groups showed some of these same sturdy, Neanderthal-like traits, just less pronounced, supporting the idea that an active, barefoot lifestyle shapes the heel in a consistent direction regardless of species. By contrast, the sedentary population from Bologna stood out as clearly different from every other Homo sapiens group in the study, with a more slender, less sturdy heel bone overall. Researchers linked that pattern to generations of wearing hard-soled shoes and living a far less physically demanding daily life.

A Foot Built for Terrain, Not Running

None of this means Neanderthals couldn’t run when they needed to. Earlier research cited in the study found that one measurement of the Neanderthal heel, the length of the back portion relative to the whole bone, suggests their Achilles tendon had a longer lever arm than in modern humans. A longer lever arm adds turning force at the ankle, handy for pushing off on uneven, rocky ground, but it also makes running more costly. That trade-off fits a species that leaned on strength and steady walking more than long-distance running.

Researchers also pointed out that some of these traits probably reflect a mix of inherited ancestral features and adaptations shaped during each individual’s lifetime by activity and body weight, rather than one single cause. Distinguishing exactly which heel traits evolved versus which were shaped by a hard, physically demanding life remains an open question, one the study’s authors say deserves further investigation that combines bone shape data with modern foot movement studies.

Heel bones rarely get much attention outside a podiatrist’s office, yet this one carries real weight in the story of human evolution. Neanderthals and modern humans walked the same planet on nearly identical skeletons, but a close look at this single bone shows their feet met the ground in genuinely different ways, each built for a different kind of life. The same pattern appears among more recent humans, whose heel bones look more delicate in populations used to shoes and less physically demanding lives.