Why is it always males that get eaten during sex?

This episode is brought to you by Focus Features. On March 27th, Focus Features invite you to be a part of the most explosive movie of this year's Sundance and South by Southwest Film Festival.

The AI doc or how I became an apocalypticist is being called supremely entertaining and the most urgent movie of our time.

The AI doc or how I became an apocalypticist rated PG-13 only in theaters March 27th.

This episode is brought to you by Indeed. Stop waiting around for the perfect candidate.

Instead, use Indeed sponsor jobs to find the right people with the right skills fast.

It's a simple way to make sure your listing is the first candidate to see.

According to Indeed data, sponsor jobs have four times more applicants than non-sponsored jobs.

So go build your dream team today with Indeed.

Get a $75 sponsor job credit at Indeed.com slash podcast, Terms and Conditions Apply.

In the middle of baby making, a female praying mantis will sometimes chop down on a male's head, then devour him as she finishes mating with him.

And mantises aren't alone. Many different species lunch on their lovers.

But one thing is remarkably consistent. It's almost always the females doing the eating.

Why is it dudes that always end up as dinner?

Hi, I'm Kate and this is Minute Food.

Oh, sorry, this is Minute Earth.

All sorts of critters will occasionally munch on members of their own species.

But here, we're talking specifically about when an animal eats its mate, or potential mate,

before, during, or right after baby making, which scientists call sexual cannibalism.

And think about it. Since females are the sex that lays the eggs or nurtures the offspring inside their own bodies,

if a male eats a female before, during, or right after mating, there won't be any babies.

So any male who regularly dined on his dates wouldn't be able to pass along the habit.

It can really only be females that make a habit of lunching on their lovers.

And sometimes, that habit really pays off.

Like killing off a baby daddy that otherwise would have helped raise the babies doesn't make a lot of sense.

But in species where males don't help out, the female gets left alone to raise the babies, sometimes a lot of babies.

Which takes a lot of energy. So if a convenient protein packed snack is like right there,

it benefits her big time to shout out.

One study found that mantis females that ate their mates laid more than twice as many eggs as those that didn't.

Which might make it seem like mate eating helps both female and male mantises

leave behind a bigger genetic legacy. But since the male ends up dead, his future prospects are over.

If he hadn't been eaten, he could have gone on to mate again and again, leaving way more babies behind.

In some cases though, getting eaten does seem to benefit males.

After redback spiders mate, the male often somersaults into the female's fangs, offering himself up to her.

Scientists think this self-sacrifice evolved because in this species, the vast majority of males get eaten by predators before they ever get a chance to mate.

So if a male redback does get lucky enough to actually get lucky, he's almost certainly not going to get another chance.

He might as well sacrifice himself to his mate to make sure the babies are well provided for.

So we've covered why males get eaten during and after baby making.

But what's up with eating a potential partner before mating?

Which guarantees exactly zero offspring from the para.

Well in certain species like fishing spiders, competition is intense.

So it really pays for females to be super aggressive.

And all that innate aggression can accidentally end up directed toward a potential mate.

Whoops!

The bottom line is that while it seems totally unthinkable to us, sometimes it does make sense for females to plate their dates.