Nature.

In an experiment, I don't know yet.

Why is Blight so far?

Like, it sounds so simple.

They had no idea.

But now the data's...

I find this not only refreshing, but at some level astounding.

Nature. Nature.

Welcome back to the Nature podcast.

This week we'll be finding out about their evolution of adorable mammal babies.

Plus new tests to try to pin down the strength of gravity.

I'm Charmany Bundell.

And I'm Adam Levy. What do puppies, kittens and baby humans have in common?

Yes, that's right, they're ridiculously cute.

But aside from that, they are also baby mammals.

Mammals split from reptiles at least 300 million years ago.

And while we know a fair bit about how we evolved from our scaly common ancestor to our cuddly present form,

we don't know a lot about the evolution of our babies.

Along the line leading to modern mammals, we don't have a lot of concrete information on how their reproductive strategies evolve.

This is paleontologist Eva Hoffman.

Mammals' reproductive strategy, in other words, how we have babies, is pretty special.

We mammals are nourished as infants by lactation from mammary glands, where the name mammal comes from, in fact.

...