Scott Evans

They start to do things like have an elongate body with a front and a back and a top and a bottom and a left and right.

That may seem very simple, but that's the way that most animals today build their bodies.

That's exactly how our bodies arrange.

We have front and back, top and bottom, and then we just repeat some things along the way, and that's how you build most animals.

One of the surprising things about these fossils is that they're found in these deep water environments below the photic zone.

And we know that from sedimentary structures.

There are certain structures that form at certain depths of the ocean.

And so we can read those to understand where we are.

And what we knew about some of the fossils we found that were familiar from places like Australia is that in Australia, there may be 10 million years younger and they're found in much shallower water environments, places where wave action can regularly impact them versus these fossils, which are found in much deeper parts of the ocean.

And so that suggests maybe that we have this progression from deep water to shallow water through time.

Yeah.

So that's one of the hypotheses is that the deep water, it seems very inhospitable.

It's dark, it's cold.

There's not a lot of oxygen, which lots of animals use to breathe and move around.

But one of the things we know is that it's stable.

The temperature doesn't fluctuate a lot.

The amount of oxygen doesn't fluctuate a lot.

Not necessarily a lot of food, but the food sources are pretty regular.

And so that might be that stable conditions allowed animal life to first appear.

And then as it got more complex and figured out how to deal with these things like fluctuating temperature, it was able to move into shallower environments where maybe there is more oxygen and more food and then really diversify.