Dave Hone

deers, you know, some massive groups, about eight or nine of them were fully feathered, as far as we can tell.

So feathers massively predate bird origins, but it was a major part of their evolution.

Yeah, it's probably a fundamental twofold one, which is feathers insulate you, they keep you warm, and most dinosaurs were...

It's an archaic term, but it's what most people know, warm-blooded.

So they were much more like us and birds.

They had a stable, high body temperature, regardless of the environmental conditions.

And so if you're burning a lot of calories to stay warm, you want to kind of keep that heat, and feathers really help you do that.

And then the other thing is, yeah, the obvious thing is sexual selection and communication.

Feathers do stuff that scales can't.

You can shed them in winter and change color and come back as another one.

That's quite a handy trick.

You can change them between juveniles and adults.

So baby birds have one type of feather.

Adults have a different one.

We know of dinosaurs that do that.

Well, we've got adults and juveniles with different feather types preserved in the fossils.

Um, yeah, you can produce all kinds of weird colors and displays.

You can, you can erect feathers, you can hold them up and fan them out like a peacock or a pheasant.

Whereas scales, you can't really do that a bit, or you need a huge amount of bone like predaceratops.

So,