Hannah Chin

And Hannah Chin with our biweekly Science News Roundup.

All right, Sasha, our first topic is about beans and bean plants' surprising chemical counterattack against caterpillars, which are a common garden pest.

I mean, we also have an episode about fiber-maxing.

It just came out.

And lastly, we've got one more story about pests.

This time it's how the bug-repellent DEET could have a major Achilles heel.

It's true.

Today on the show, adaptation for better and for worse.

You're listening to Shortwave, the science podcast from NPR.

In this case, it's caterpillars.

So, Sasha, in a study out this week in the journal Science Advances, researchers described how when caterpillars munch on bean plants, a compound in the caterpillar spit causes the bean plants to release a chemical signal into the air.

Think about it as a kind of distress flare that calls in a fleet of wasp bodyguards.

So this is Adam Steinbrenner.

He's a plant biologist at the University of Washington, and he's one of the authors on the study.

He says some of the wasps eat the caterpillars.

Others lay eggs inside the caterpillars' bodies so their babies can eat them, really effectively removing the threat to the bean plants.

Yeah.

And these are both chemical responses, right?

But the specific compound that attracts wasps is really only triggered via caterpillar spit.

So the bean plant doesn't call wasps in if, say,