Darby Saxbe

But in mammals, it's fairly unusual to have biparental.

Exactly, which is where the term mammal comes from, right?

So it comes from milk.

So literally, it's baked into the term that this is a mother-centric animal.

And I mean, you do have some examples of primates and rodents where males are participating in rearing.

But what makes humans unusual is the sort of flexibility and the fact that we raise children kind of collectively, right?

And so that's called cooperative breeding or alloparenting.

And that's sort of our signature style of how we raise kids.

Yeah.

Exactly.

Like a lot of shared care.

So you kind of need a complex social brain that can track who's safe.

And the reason I think that style originates is just because our babies require so much care.

Like our human babies are so half-baked when they emerge.

And so you really need this tag team.

And then fathers become really important.

Hunter-gatherers live in these small sort of mobile bands of 20 to 30 people.

There isn't a lot of private enclosed space.

We don't have our big houses and our backyards.

So everybody is helping everybody and parenting looks pretty collective.