2008, we're out on the middle of Lake Huron with John O'Shea, and he's an anthropological

archaeologist.

He's also a professor at the University of Michigan.

This is Morgan Springer.

She's a contributing editor and producer for Points North,

a podcast from Interlochen Public Radio in Michigan.

And he's in a boat and he's searching for signs of prehistoric life and he's using sonar to just survey the lake bottom and look and look.

Which meant driving a boat in very straight lines for hours and hours and

hours in good weather and bad to build up a mosaic image of what the bottom looked

like in an area then once you have that you can look at that map and say,

ah, this might be something, this might be something.

And then they did find something.

An ancient caribou hunting site, which they could tell this because it's basically a line of stones that was put there by hunters and those stones would guide the caribou to the hunters kill site.

And this was prehistoric. It was about 9,000 years old. Totally incredible.

I mean, that's really old.

Yeah.

That's like super, super prehistoric.

Like obviously it wasn't underwater 9,000 years ago.

Why is this caribou site where it is?

This hunting site that they found,

it's on this landmass that's called the Alpina Amberly Ridge.

And it goes all the way from Northern Michigan to southern Ontario. It's like cutting Lake Huron at a diagonal. And it's really long. It's 90 miles long. And it was kind of this causeway for people and animals to travel on and

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