Hi there, I'm Jason Gautz, and you're listening to Think Again, a Big Think podcast.

When I was a kid, there used to be a TV commercial for this series of animal videos.

You could order that were basically nothing but killing and sex.

The tagline was, find out why we call them animals. Wait a minute, I used to think.

That's not why we call them animals. Also, we're animals too, aren't we? What exactly are you trying to

say? That video series was a cynical cash grab, but it's not too far removed from how science

has approached animal research

with some very recent exceptions. Generosity, empathy, happiness, reconciliation. These rich

emotions and pro-social behaviors were for humans. The animal kingdom was about dominance,

survival, and the right to reproduce. Hey, it was a jungle out there.

My guest today, primatologist Franz de Wall, has spent decades gathering field and laboratory

evidence that the line between humans and the rest of the animal kingdom is very blurry

indeed, and that emotions are the deep connective tissue across species. His wonderful

new book, Mama's Last Hug, will help you find out why they call us animals.

Welcome to think again, friends.

Thank you.

First of all, and probably most important, I need to ask your advice on taking care of fish.

Oh yeah, you have fish?

I have some fish and they just die.

Maybe you're feeding them too much.

Maybe I am. All my life since I. Maybe you're feeding them too much. Maybe I am.

All my life since I was six, I've had aquariums.

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