Connexion
The Stone Age owes its name to tools that survived to our time. The material early humans worked with most, though, was probably wood because it is so much easier to process. Unfortunately, we know very little about Paleolithic woodwork because wood rots relatively quickly. But at Abric Romaní, a rock shelter in Capellades, west of Barcelona, mineral-rich water coated wooden Neanderthal tools in a limestone-like crust. When wood rotted away, it left behind hollow molds that faithfully reflect its shape.
In a recent Science Advances study, a team of Spanish archaeologists has cataloged 597 wooden remains from Neanderthal living areas dating from 62,000 to 40,000 years ago. They found spears, digging sticks, bark trays, parts of shelters, and a club unlike anything seen before, suggesting Neanderthals were likely much more than just Homo sapiens’ dumber cousins.
The oldest wooden artifacts we have are mostly weapons. They include spears from a German town called Schöningen, a spear tip from Clacton-on-Sea in England, and the spear found alongside an elephant skeleton in Lehringen, Germany. Most came from waterlogged sediments, where a lack of oxygen slowed decay.
When the history of our ancestry is written, the fact that we've interbred with some of our closest relatives, the Neanderthals and Denisovans, will have a central role. And it will be tempting to write it as a very tidy story: Once we got genomes from these other groups, it was possible to identify the sequences in our genomes that we shared with them.
But in reality, as scientists started poking large enough collections of data, there were regular hints of some strange ancestry in our genomes. It was hard to pin down, though, at least in part because the 2 percent on average of Neanderthal DNA found in many populations does not guarantee that any two individuals will have the same 2 percent. So having the genomes of those two groups made sense of some things researchers had already been seeing.
But knowing what we do about Neanderthal and Denisovan DNA is now allowing researchers to answer a somewhat different question: Is there anything else? Using recently developed analytical techniques, they find evidence of a third lineage that we apparently interbred with before any modern humans left Africa. Again, there were hints of this earlier, but so far, there has been no genome from a modern human relative to help us understand the details—the source of this DNA remains a "ghost lineage."
One way archaeologists learn how ancient people, including Neanderthals, did things is to attempt to do those things themselves, a process called experimental archaeology. Normally, that involves making stone tools, butchering deer, or distilling birch tar. But in a new study, it meant doing very destructive things to teeth from one of the world’s most carefully protected animals.
That's because the archeologists suspected that Neanderthals once used rhino teeth as tools. By using the teeth to make stone tools, the researchers demonstrated that Neanderthals probably did the same thing, adding to what we know about the wide range of items in their toolkits.
Some Neanderthal archaeological sites in Europe and Asia seem to have many more rhinoceros teeth lying around than you’d expect. We know Neanderthals hunted a now-extinct species of rhinoceros in Europe and eastern Asia, but the people who had inhabited these sites looked like they had been collecting rhino teeth for some reason.
The world’s first dentist was a Neanderthal, according to a recent study.
59,000 years ago in what’s now southwestern Siberia, a Neanderthal had a toothache. It must have been a doozy because they were desperate enough to sit still while someone drilled into the tooth with a sharp stone tool, removing the infected tissue and ultimately relieving the pain.
The process left behind a hole in the tooth that paleoanthropologist Alisa Zubova of the Russian Academy of Sciences and her colleagues recognized, tens of millennia later, as dental work. Archaeologists unearthed the tooth at Chagyrskaya Cave in Russia, and it’s now the oldest known evidence of dentistry—or any direct medical treatment.
If you look at a Neanderthal skull and a Homo sapiens skull, they're visibly different: Neanderthal skulls are lower and longer, whereas ours tend to be rounder. However, those differences probably don’t say much about the brains within them, according to a recent study, which compared MRI scans of modern people’s brains with casts of the inside of Neanderthal skulls.
The results suggest that there’s more variation in brain size among modern people than between Neanderthals and Pleistocene Homo sapiens. And because brain size is actually a terrible way to predict cognitive capability, Neanderthals could have been a lot more like us than some previous studies have claimed, which definitely fits what the archaeological record tells us about how they lived. It would also mean that our species probably didn't out-compete the Neanderthals by being smarter or more adaptable.
Years after you die, the inner vault of your skull will hold the shape of your brain; if future archaeologists make a cast of that inner space, they’ll get a neat resin model of the outer contours of your brain, called an endocast. (Sediment that filled the skull of an Australopithecus africanus child who died 2.8 million years ago did this naturally, creating an endocast that’s half rocky brain-sculpture and half sparkling crystal.) For years, researchers have studied endocasts of Neanderthal skulls, trying to piece together how their brains were different or similar to ours. And that has been a matter of some debate.
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