Ari Daniel

We head now to the Democratic Republic of Congo.

Pasifik Kiwele Mutambala is a PhD student at the Université de Lubumbashi there.

And he told me that 17 years ago, a researcher from his university traveled to a waterfall in the south of the country where he saw something remarkable, Regina.

Some fishes can climb up the waterfalls.

It's incredible.

They're called shell ears.

Each one's the size of a fat French fry that can scale this 50-foot rock face behind the waterfall.

Now, this behavior of climbing, it's been documented in fish and other parts of the world, but Pacifique says never before in Africa.

That researcher 17 years ago, he filmed the phenomenon but ended up losing the footage.

Devastating.

And so that's why Pacifique, as a master's student, was determined to go get some evidence.

So for a few years running during the rainy season, Pacifique visited the raucous Luilombo Falls, which you can hear in this video that he took, in search of upwardly mobile fish.

He got drenched.

But he says it was worth it.

He saw thousands of these fish shimmying up the vertical rock surface.

Right.

This is Stephen Cook.

He's a fish ecologist at Carleton University in Ottawa, and he wasn't involved in the research.

I love the Canadian references.

Stephen says the shell ear migration may seem to pale in comparison to something like that of a wildebeest, but it's just as important.