This is Science Friday. I'm Iraflato. I've had a good idea. The weekends here, let's talk about nematodes and dung beetles. Why not? They interact a lot in nature. The small worm-like parasites like to hitch a ride on their insect partners as they fly from one dung patty to another. Sounds like a pretty sweet deal for the nematode, right? But perhaps not so much

for the dung beetle. See, the nematodes actually ride on the beetle's genitals, where they can be

passed on to their offspring or mates like an STD. Now, dung beetles put up with a lot of dung, but what do they stand to gain from this relationship?

My next guest says, as icky as it sounds, there might be a very good reason for letting those parasites climb aboard.

Dr. Christina Ledunredig is assistant research scientist in the Department of Biology at Indiana University in Bloomington.

Welcome to Science Friday.

Hi, Ira.

So tell me about this ride-sharing arrangement between the dung beetle and the nematode.

How do these two organisms interact?

Gladly.

Well, when a dung beetle is ready to reproduce, they tunnel underneath a dung patty, and they create these developmental chambers out of dung that we call a brood ball.

And in each of those brood balls, they place a single egg.

And from being an egg to an adult beetle, that developing beetle depends on this developmental chamber for its nutrients, for its shelter and protection.

And nematodes ride along on these beetles. They're small worms.

And they end up in these developmental chambers along with the developing beetles.

And we didn't know before whether that was a good thing or a bad thing.

But we did know that this association existed.

And so this was something that we wanted to investigate more to understand the consequences

of that interaction.

So tell me, tell me.

What did you learn?

Well, we looked on all different parts of the beetle for nematodes, and we found them on various

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