Dr. Steven Novella

So they just were hanging out at the bottom for a billion years or whatever, hundreds of millions of years.

It's stable down there.

They're protected down there.

They had good oxygen concentrations down there.

So that's where they were hanging out.

Why were there good oxygen concentrations down there?

Because they just sort of cling.

I think because the oxygen is being produced down there and it sort of clings to what's down there.

And again, it's not necessarily everywhere, but wherever there was pockets of high oxygen, that's where they were staying.

And they just couldn't get through the pockets of low oxygen to get to them.

Oh, my God.

Now, how do we know they were in high-oxygen areas?

Because, again, not all areas had high oxygen.

And that's chemistry, right?

Because you could look at the minerals.

These are oxygenated, right, basically.

These are things that form only with oxygen.

this much oxygen.

So we only see- Yeah, they've probably found little mini oxygen tanks and stuff.

Yeah, we only see these eukaryote fossils in high oxygen sediment or rocks.