They are very unlike a bird that you typically think of sitting at a bird feeder.

You know, it's definitely not that kind of bird.

I'm Flora Lichtman with Scientific Americans Science Quickly.

Today, episode three of our four-part fascination on really big birds.

We're going on a gargantuan goose chase.

I love talking about these big birds because most people think ostrich and they think that's big,

but actually they were real giants around at one time.

This is Aniseach and Sami Tehran of the University of Cape Town in South Africa.

And she's talking about the Dremorna Thids. That's their scientific name.

But in big bird circles, you'll hear them called Thunderbirds.

They name the Thunderbirds. It's really quite wonderful because kind of immediately you can

understand these really large animals coming. Thunderbirds lived in Australia and they had a long run.

The earliest members of the group date back 50 million years or so and one species persisted

to about 40,000 years ago. And there was one Thunderbird that was more thunderous than the rest.

The largest are the Thunderbirds called Dremorna Stur tonight and they are known

from the late Mayu scene about 8 million years ago.

Here's what to picture. I think it's like an overgrown ostrich.

Just kind of bigger, big, big, the bones that have been heavier,

more bulky, more robust.

But like a lot bulkier and more robust.

Absolutely. Some of the few just birds on the planet were on the planet.

This is paleontologist and Thunderbird expert Trevor Worthy.

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