Fire Ants Turn Into a Stinging Life Raft to Survive Floods

During hurricane season, as floodwater flows into their nest, red fire ants build a terrifying raft – out of their own interlocking bodies. If you wade into this ant raft nightmare, you’ll likely get a vicious bite and sting.

TRANSCRIPT

This soft mound of dirt is home to some tough insects: red fire ants. They’re all over the southern U.S.

And if you get too close, you will regret it. They clamp onto you with their huge jaws. And then they sting. Over and over. Rude.

They inject nasty venom that burns and causes itchy welts to pop up.

And if you think they’re scary on land, you’re gonna absolutely hate ’em during a flood.

Imagine wading into one of these. This floating nightmare is made out of thousands of fire ants. They’ve escaped their flooded nest by making a raft from their own bodies.

Here’s how they pull it off.

As flood water trickles into the tunnels below their mound, fire ants start a rescue mission. They evacuate the colony’s babies – these larvae and pupae – to the surface.

But researchers at Louisiana State University found that instead of putting the babies on the top of the raft, where it’s dry, they put them on the bottom.

Listen, these ants have their reasons.

See the halo of hairs on these larvae? If you look at the raft from below you’ll see how those hairs trap air bubbles and hold the larvae together in clusters, you know, like giant floaties.

Those same bubbles help everyone breathe through tiny holes on the sides of their bodies.

And hey, don’t feel bad for these ants with their heads dunked underwater. They’ll get their turn on top of the raft eventually.

Workers grab onto each other by the tips of their legs, called tarsi. Some of them hold onto the larvae, too, and lock legs … like ant scaffolding. And then they’re ready to set sail, wherever the water may take them.

Ants make these rafts really quickly. Check out this experiment. A researcher at Georgia Tech drops a ball of fire ants into the water. It only takes them two minutes to assemble.

This ability has helped red fire ants spread across the world from South America, where they evolved along the rivers’ edge.

Rafts can stay afloat for almost two weeks. They survive on food they brought in their bellies.

With the whole colony to protect, workers are extra defensive. They sting with more venom than usual. Not a good time to run into them.

When the water recedes, they’ll dig a new nest … and live their best fire ant life, eating whatever crosses their path and stocking up for their next getaway.

Hey, Maddie here, with a riddle for you. Why does a Mexican jumping bean jump? Watch our episode to find out. Thanks!