From a Darwinian perspective, monogamy seems a little weird.

Right? I mean, think about what you're giving up when you choose to have only one mate.

If you're a male mammal, you could theoretically impregnate a different female every single day of your life.

Monogamy means that your reproductive rate, which could be very high, is now slowed down to the

female pace, which is much slower than yours, perhaps months of pregnancy per offspring.

And if you're a female mammal, well, monogamy means that all of your kids are going to be

from the same male, which means that your offspring have severely limited genetic diversity.

So cross your fingers and pray that there aren't any dilaterious, shared, recessive traits in the fellow you chose.

And pray you're interfertile with him, too, while you're at it.

And pray he was a good choice, because after all, you only get one.

Monogamy is putting all of your eggs in one basket, and then limiting yourself to the eggs that happened to be in that basket.

So, perhaps it's not surprising that it rarely evolves, hardly ever in mammals.

But it evolved in our lineage to an extent, and in some of our cousins, too, in the Gibbons.

And today, I'm going to tell you about my favorite species of Gibbon,

the Siamang, Simphalangus, syndactylus. I'm Mackin. This is Species.

Welcome to the show. I am so excited to speak to all of you today. Gibbons are among my favorite animals on Earth. And as I said in the introduction, this is my favorite species of Gibbon. And they've been long requested, so it'll be good to get them ticked off the list.

Thank you to all the donors for your continued support.

It is a tremendous honor to have you all funding this show.

And thank you to everyone for tuning in.

It's so gratifying to see that all of you stuck around.

Thank you for your patience.

It was cool, incredibly cool to see the Tardigrade download numbers

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