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Out in South Africa, there's a team digging for clues to unlock one of the most elusive

murder mysteries of all time.

Regina Barber here and I've been called to help on a new case and it begins with our

detective Dr. Salina Sores.

We find our clues in rocks and fossils within those rocks.

Well, a detective of a different kind. Salina's a paleoclimatologist at the University

of Arkansas and she spends her days either in the lab or out in the field hunting for answers.

A paleoclimatologist's goal is to reconstruct the climate in the past and understand how

that climate has changed over time.

Salina's unraveling the mystery behind a mass extinction on Earth.

There have been five mass extinctions in the history of Earth and Salina's team of

wild investigators is focused on the fourth one.

This is not the asteroid that wiped out the dinosaurs.

It's the one before that.

Back when Pangea was still around, it's called the end of Triassic extinction.

So that was a mass extinction that happened about 200 and 1 million years ago.

This mass extinction was just before the dinosaurs basically came to dominate the globe.

But there's our mystery.

Because no one really knows why the dinosaurs took over.

The Dino ancestors didn't look like much.

They were no bigger than modern day chickens.

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