Modern humans evolved in Africa, but soon spread around the world. However, we weren’t the first member of our family to do so. Nearly 2 million years earlier Homo erectus took a similar journey across the world. By ~1.2 million years ago they’d arrived in Western Europe. Examination of their fossils reveals they managed to make this trip without the luxuries we had during our migration. They lacked fire, fancy tools, and likely clothes. But it turns out they did have toothpicks.
Homo erectus is a species a lot like us (to the point some speculate they may be our ancestors). They had large brains, spent their lives walking upright on the ground, and evolved in Africa but soon left. However, they did it all more than a million years before us. The evidence for their earliest push out of Africa comes from the famous Dmanisi fossils; dated to ~1.7 million years ago. By contrast, the earliest modern humans in the region date to closer to 50,000 years ago.
Despite leaving our homeland so long ago, it took Homo erectus a while to spread out. Dmanisi indicates they arrived on the eastern edge of Europe by 1.7 million years ago. However, it isn’t for another 500,000 years we get evidence of them spreading out into Europe itself. It seems to take them another half a million years to fully colonise it, eventually making it to Norfolk by 700,000 years ago.
Even this long chronology is being a bit generous to Homo erectus. The earliest evidence of hominins in Europe is found in Spain and Italy ~1.2 million years ago. However, these early fossils are incredibly fragmentary. Arguably the best-understood fossils from this period are those from Sima del Elefante (“pit of elephants”) in Northern Spain. Yet all we have from the site is a bit of jaw with a few teeth. As such, we can’t even guarantee they even were Homo erectus. Since they were the only species migrating during this period, it seems likely. But science is nothing if not cautious.
Science is also pretty awesome. So despite the fact we have so little fossil that we can’t even say for sure who they were, we still know an awful lot about these first Europeans. Like what they ate, where they lived, the fact they didn’t cook food, and their use of toothpicks.
If you don’t brush your teeth properly plaque can build up. This eventually becomes calculus, a tough substance you need a dentist to remove. Of course, Homo erectus didn’t have modern dentists. So their calculus survives, along with microscopic remains of food. As such, even a single tooth can shed a boatload of information on the environment, diet, and behaviour of individuals. Archaeologists of the future are really going to hate modern dentists.
For now, though, let’s focus on Sima del Elefante. All bar one of the teeth found there has calculus, shedding light on these fossils.
For starters, some fibre was found in this calculus. Much of it seems to be from plants, including some inedible wood. However, some of the fibre lacks cell walls, indicating its from an animal. We can’t tell how common meat was in their diet, nor whether they hunted or scavenged. But it seems these early Europeans did at least eat some meat. They also seem to have eaten grasses, as indicated by the size of the starch granules also found in the calculus.
These food particles show no evidence of extensive modification, suggesting they weren’t ground up or otherwise prepared before being consumed. This includes cooking. That definitely didn’t happen, suggesting this group likely didn’t have regular access to a fire. This matches the previous evidence, which has failed to find any sign of fire during this period. However, it was hard to know if that wasn’t just because we hadn’t found it yet. It seemed strange that hominins would expand into their coldest region yet without such a key survival tool. But this calculus seems to confirm they did just that.
As well as trapping food, calculus can also trap pollen; entering our mouth as we breathe in. Based on this, it’s possible to partially reconstruct the environment at the time. Spores and even bits of insect can get in through a similar process, helping clarify this picture. Taken together, all of these indicate the early Europeans likely lived in a forested environment, with conifer trees.
The other way of learning about these hominins from their teeth is looking at the wear on the tooth and jaw. Which in this case is quite extensive. This could indicate they were eating incredibly tough food, but the calculus hints at another answer. Remember how it contains some inedible plant fibres? Some modern groups use their teeth as a “third limb”, holding stuff in place whilst they work it with both hands. It seems that these early Europeans were likely using their mouths during some woodworking.
One aspect of this wear is quite interesting. There is a deep groove just above the calculus deposit. More inedible plant material was recovered from this scratch. This pattern is seen in many modern groups, including some primates, when a wooden implement is regularly used to clean the teeth. Chimps in captivity, for example, will try and scratch their teeth clean with small twigs.
So it looks like these early Europeans were using toothpicks or some other wooden implement to try and keep their teeth clean. Given this has been seen in chimps (and earlier hominin fossils) it shouldn’t come as that much of a surprise. Much like the fact that it already seemed likely they didn’t use fire.
In fact, nothing about these discoveries is a massive shock. Most of it has been hinted at by previous discoveries. What we have here is a great source of knowledge about the everyday life of these first Europeans. Nothing attention grabbing, but instead, these are incremental improvements on which most science is based. And in clarifying our picture of the day to day life of hominins 1.2 million years ago, it helps make them seem that much more human.
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