One thing that I got from your work that really blew my mind was the idea that, okay, well,

I know that we have bigger brains than other animals, and that's our special thing, right?

But you kind of make the point that there had to be a kind of metabolic miracle.

There had to be this jump in our energy processing systems to create essentially the extra brain

energy budget necessary to become humans.

Yeah, that's right.

So to be able to fuel all these expensive traits, big brains, big babies, really physically

active lifestyles, right?

Big brains and big babies is an amazing way of describing homo sapiens.

Hello and welcome to Why is this happening with me, your host Chris Hayes.

Well, it's a beautiful day.

It's a beautiful spring day in New York City, and I'm vaccinated, and a lot of people I know

are vaccinated.

And spring is always a time when we kind of emerge from winter quasi-hybernation, particularly

in the parts of the country that get cold like the Northeast where I live or the Midwest

where I used to live.

And there's a bit of special hibernation that's happened with COVID.

People have jokingly referred to the COVID-19, meaning the 19 pounds they packed on during

their inactivity during COVID.

But I think that it's fair to say that most of us were more sedentary than we'd normally

been for a long period of time.

Gims were closed for one thing.

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