In the 1970s, archeologists made an exciting discovery in a small town near the Belgian-French border: a graveyard from the 2nd century CE.

Its occupants were Gallo-Romans, members of celtic tribes who  lived in the Roman Empire. Or at least, that’s what the archeologists thought for half a century.

Because one grave was the odd one out. Instead of cremated remains, there was an actual skeleton inside it. And scientists recently realized that only its skull was Gallo-Roman.

The rest of the body is thousands of years older, and was made of at least seven different people. Someone, at some point in history, went through a bunch of effort to put together this particular puzzle. But why? [SciShow Intro] Now, when those original  archaeologists discovered this body, they based its age not on the skeleton, but on an artifact that had  been buried with it: A bone pin.

Bone pins were used as  hairpins during Roman times, so it was a reasonable hypothesis that the skeleton it accompanied would date to the same time period. But the team had ignored multiple red flags. First off, the skeleton was on its side with its limbs tucked up, kind of in a fetal position.

And when the Romans buried their dead, they laid them flat on their back, legs outstretched, arms at their side. This curled up position was reminiscent of much older burial practices in the area. A second red flag was that  just looking at the bones, you can see that some of  them don’t quite match up.

Some looked much younger than others, and some of the vertebrae  didn’t quite fit together. So nearly 50 years later, a 2019 study finally brought  in good ol’ radiocarbon dating to get a clearer picture. Radiocarbon dating is a way to figure out how long ago something died by looking at a particular  type of carbon, carbon-14.

Like all living things, we’re constantly absorbing carbon into our bodies as we go about our daily lives. The vast majority of it is a  stable form called carbon-12. However, we also absorb a teensy  tiny bit of the much rarer, and radioactive carbon-14.

Every 5,730 years, half of the carbon-14 atoms decay and break apart. That decay keeps happening after we’re dead, but being dead, we’re no longer replenishing our supply. So by comparing the amount  of carbon-14 to carbon-12, you can figure out how long something’s been dead.

In the case of this Gallo-Roman cemetery, carbon dating confirmed  that the 76 cremated graves were indeed from Roman times. But it also revealed many of  the single skeleton’s bones were thousands of years too old to be Roman. So a 2024 study took an even closer look with more radiocarbon dating and DNA analysis.

And the team realized just how confusing a puzzle they had on their hands. But before we get into that, we’ve got to keep the lights on. So first, an ad Thanks to Brilliant for supporting this SciShow video!

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That link gives you 20% off an annual premium Brilliant subscription. The radiocarbon dates reveal the bone pin was indeed from Gallo-Roman times, But all the skeleton bits they dated came from the Late Neolithic Period. And not just one point in the Late Neolithic.

They ranged anywhere from 3333 BCE to 2675 BCE! So someone put together a  normal-looking human body with something like 650 years’ worth of bones! Meanwhile, the research team wasn’t able to get a carbon date from the skull, but they were able to extract some DNA from it.

And by analysing that DNA, they revealed the skull belonged to a Gallo-Roman woman who was genetically related to remains at another archaeological site about 150 kilometers away. And because those remains did have a carbon date attached to them, the team could estimate how  long ago this woman lived. At most, she and her genetic  cousins were 28 generations apart.

Roughly speaking, that’s 784 years. So there’s still some uncertainty here, but it means the skull sitting on top of this otherwise Neolithic skeleton was at least 2500 years  younger than the rest of the skeleton. Meanwhile, DNA analysis also confirmed that the other bones came from at least five different people who weren’t close relatives of each other.

But based on how the bones match up physically, or, rather, don’t match up, the researchers think the remains of at least seven people came together in this one skeleton. and in case that wasn’t weird enough for you, there are also three badger bones found in that grave, too. each comes from a different badger, and each separated by thousands of years! So now archaeologists have to figure out who did this, when, and why. First, they have to consider the possibility that this puzzle all stems  from an archeologist’s error.

Did someone on the original team mix up the remains after they were excavated? The team behind this 2024 paper  thinks that’s pretty unlikely, since the skull was genetically  related to other graves in the area. So if we don’t have to worry about that, was this composite skeleton created by the Gallo-Romans from much older bones?

It’s possible. And if true, it’d be the first of its kind. But then why didn’t the  Gallo-Romans lay the skeleton out like they would the rest of their bodies?

Why the even more vintage fetal position? So the most likely scenario  is that the composite skeleton was created during Neolithic times, and then disturbed by the  Gallo-Romans millennia later. Archeologists have a few other examples of ancient composite skeletons, although they’re not as old as this one, and usually only feature a few  different people’s remains.

Not seven. Still, they can draw comparisons,  and speculate the why of it all. I mean, sure, this could just be someone’s idea of a prank for future  archaeologists to stumble upon.

We can’t completely rule that out. But a more, perhaps realistic, hypothesis is that they crafted a single skeleton out of otherwise unrelated bones to serve as a symbol of unity. Maybe Neolithic Belgians were really into found families.

Whatever the why, the ancient people who created this composite had a detailed knowledge of human anatomy. They put all the right bones in the right places. Fast forward two and a half thousand years, the Gallo-Romans might have been burying their cremated remains and accidentally disturbed this much older grave.

We know the Romans had a reverence and respect for human remains. So perhaps they noticed the skull was missing, and replaced it with one of their own to complete the body before reburying it. This could have been their  way of making reparations for the disturbance.

While there’s still some guesswork involved, here, it’s clear this skeleton tells a complex tale That spans many generations and cultures [ OUTRO ] [ OUTRO ]