This is an I-Heart podcast.

Guaranteed Human.

If I could go back in time to witness any historical moment,

going back in time to observe ancient human species would be near the top of my list.

How do they build their fires? How do they treat their children? How do they solve problems and how do they communicate

with each other? Do they dance? Do they sing? Do siblings argue with each other? But, unfortunately,

Daniel hasn't figured out time machines yet, so I'm kind of stuck for now.

In the absence of time machines, the best we can do right now is search for fossils and try

to learn what we can from things like the shape of these fossils and the DNA that's sometimes

left behind. And lucky for us, we have Dr. Scott Solomon back on the show to tell us about what we've learned so far about ancient hominins.

And that's almost as good as a time machine.

Welcome to Daniel and Kelly's Extraordinary Universe.

Yeah. Hi, I'm Daniel. I'm a particle physicist, but I don't remember the moment that I became human.

Hello, I'm Kelly Weiner-Smith. I study parasites and space, and thank goodness we don't remember the moment we became human. I'm guessing that that is a biologically, you know,

a private moment between your parents, probably.

Oh, I don't know. I don't feel like I was human at birth. I don't feel like I was me at birth.

I was just a screaming blob.

I think it's fascinating that what emerges from that is a sense of self, a sense of who you are,

but you can't really trace it all the way back.

Like, its origins itself are sort of lost to your own memory.

I feel like that's similar to how, like, as a species,

we have some

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