Vertebrate history has bite marks all over it because in astounding ways the evolution of teeth transformed the animal kingdom.

I like them right up there with the backbone as the most important adaptations that

vertebrates evolved.

It's Thursday, August 29th, and this is Science Friday. I'm Cyfry producer Rasha Arredi. Teeth have existed in some form

for half a billion years. They evolved far before warm-bloodedness, before eggs, even before limbs.

And from that very first set of trappers emerged a bewildering and diverse group of teeth. includes Narwalls tusks, sharks

pearly teeth, snakes bings, and of course our own. Here's guest chose to Magi Kirth

with more. Now teeth are the subject of a new book called Bight, an incisive history of teeth from hag fish to humans.

It explores a variety of tooty adaptations, how they came to be, and how their evolution helped transform the animal kingdom.

Joining me is zoologist and author Bill Shut, based in New York.

Bill, welcome to Science Friday.

Thanks Maggie. It's really nice to be back.

It's really nice to have you.

So Bill, is it dramatic to say that teeth changed the world or at least that they changed the animal kingdom?

No, I think that's that's perfect. You mentioned that they showed up around

500 million years ago and I'd like them right up there with the backbone as the most important

adaptations that vertebrates evolved and I think that teeth were incredibly important to allow them to obtain and

process food in all sorts of different environments and really that was the

key or one of the keys to the success of the group and the diversity of the group.

Well and they changed not just the animals but the environment the animals lived in too, right?

So like you get beavers that are building dams because of their teeth and parrotfish

pooping out sand because they can munch on corals.

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