Peter Attia, M.D.

How much can that happen?

Wait, there's a lot for me to unpack here.

No, no, no.

But I want to talk about this.

Everything you're saying is totally new to me.

Okay, so let's talk about that first, but then I want to go back to the birth control and stuff like that.

Man and wife have baby.

Man decides after a few years, I'm going to stay home more and spend more time with my child and forego whatever else I was doing.

So I used to be working 80 hours a week.

I'm now going to work 30 hours a week.

But in this experiment, this guy decides to stay home half the time now.

His testosterone will drop.

The kid's five at this point.

He benefits reproductively because that's a critical window in which his protection is producing his survival advantage.

There's so much to unpack there.

Again, these evolutionary discussions are so interesting because I have to imagine that most guys who have chosen the path on your right, which is I'm going to have as many partners as possible.

are not doing that because of reproductive fitness.

They are often choosing not to have kids.

That's right.

How do we reconcile that?