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Nothing gets paleontologists y'all are pretty more excited than very, very old bones.

Bones can tell us how old animals got.

Bones can tell us how often the animal would go into something like hibernation.

It can tell us if the animal laid eggs or not.

Like bones are the libraries of the past.

She's a PhD student at the Museum for Nathirkunda in Berlin, Germany, where she studies

bone evolution.

She looks at bones that are anywhere from 10,000 to 480 million years old, digging for clues

that help explain why do we have bone?

Why is bone shaped the way it is and why does it work the way it does?

And as part of her research, Yara studies osteocytes, cells that live inside the bones of

most animals, including us, to help maintain them.

Bones are absolutely these stars when it comes to bones and bones, they talk to each

other and they sense pressure, they sense changes in chemistry, and they basically tell the

rest of the osteocytes around them if it's all good or if they need to destroy and rebuild.

So they definitely are in the middle of all kinds of bone changes.

But here's the kicker.

In the fossils that Yara looks at, these osteocytes aren't there anymore.

They died a long time ago with the animal.

So what I'm doing is basically studying the ghosts of these cells, the footsteps that

are left behind, the shape that's left behind in the bone that is the perfect cast of these

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