It's to the best of our knowledge. I'm Antstrain Champs.

Have you ever had an experience you just could not explain?

We were doing field research to basically collect everything we could about the chimpanzee community there.

Wildlife biologist Laura Kiho, this was in Guinea, West Africa.

We were sort of just trundling through the bush, and we stopped at a clearing.

And this guide, Mamadu Aliubah, incredibly talented guy, he had found some markings on a tree.

Other local people thought that these were probably just wild pigs or teenagers or something else.

But Mamadu was sure that there was something more to it.

So we put up a camera there for a few weeks to catch what it can and we essentially moved on.

Finally two weeks came and I was pretty excited just because you kind of dream when you're in the field that you'll find something new or interesting.

What we saw was, uh, Tim approached the tree.

Pause, look around.

Pick up this huge rock and fling it at the tree.

And then basically run off.

And there was a pantout as well that he did.

I hadn't seen anything like that before.

And it turns out that it was an entirely new behavior that

hadn't been recorded before. We still don't really know what it means, but that's what we found.

Now, I can hear you thinking, seriously, an ape throws a rock at a tree. This matters why? First of all, it's not just one chimpanzee.

It turns out to be dozens of them all over West Africa.

Second, the behavior looks to scientists like some kind of ritual.

And the reason that matters is that it might, just might, help explain the origin of religion.

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