Have you ever wondered what would happen if a bunch of ants fell down a hole into an old Cold War bunker with no way out?

No? Just me?

Well, while this sounds a bit like the beginnings of an entomology-themed horror film, it really happened! And how these ants acted under such extreme circumstances can tell us about what those ants do normal– because even trapped in a nightmare, they kept on ant-ing. [♪ INTRO] Allow me to set the scene. It’s the early twenty-tens in Poland, in a long abandoned Soviet bunker that once housed nuclear missiles during the Cold War.

Inside the bunker is a colony of wood ants. Although, I use the word colony loosely here because these ants didn’t choose the bunker life. This bunker is underground and covered over with trees and dirt as camouflage.

Inside, it’s cold, dark, and mostly empty after being sealed off and made illegal to enter by authorities. Wood ants are pretty common in these forests, and a colony of them happened to build a nest over the top of a vertical ventilation pipe for the bunker. Over time, the pipe’s metal outlet covering rusted through, leaving a hole.

This caused ants from the nest above to fall onto the bunker floor below, with no way of getting back up or out of the bunker. But that didn’t stop the ants from doing what they do best: nesting. A team of researchers were tipped off to the presence of this nest and found a way into the bunker.

Because what are a few trespassing laws when there’s science to do? Once inside, the researchers could see these ants were building and maintaining a nest, removing dead ants, and depositing them in ant cemeteries far from the nest to keep it clean and prevent any potential disease from spreading. And all of this this is very normal ant behavior.

But, the only ants they saw were workers – no queens, drones, or larvae. The constant rain of ants through the ventilation pipe was the only thing sustaining the bunker’s population. And there was evidence that these ants had been at it for years, doing their ant thing under some pretty harsh conditions.

But what were they eating down there? Well typically wood ants feed not on wood, but on the waste produced by aphids as they feed on tree sap. But there’s no aphids in an underground bunker.

When the researchers inspected the ants in the cemeteries, it became clear they had been snacking on each other. Which is not super surprising, given the lack of other available options. Now typically, cannibalizing your friends isn’t something social insects, like ant colonies, do on the regular.

However, wood ants are a known exception to this rule. Every spring, when various forest colonies are coming out of their winter dormancy period, they engage in ant wars, killing each other en masse and then feasting on the corpses. This establishes colony borders, and provides food for the victors in the early days of spring when food is scarce.

Also, I want you to know that “ant wars” is in fact the term used in the published literature. So, snacking on other wood ants is actually normal! Eating members of the same colony is not that normal until they’re desperate.

But, our bunker ants were just doing what they had to do to survive. And they probably didn’t flinch too much at this choice, considering they’re already predisposed to the behavior. Now, in case you were worried, the researchers didn’t just finish their research and bounce out of there, leaving the bunker ants to their own devices.

Instead, they assembled a vertical boardwalk out of a two by four, to connect the floor with the ventilation pipe and give the bunker ants a way to reunite with their original colony above. So hopefully, that put an end to it all, at least for this particular bunker! Now a Cold War bunker full of ants is one of the worst things I can imagine getting someone for the holidays.

Our merch site, dftba.com/scishow, has lots of gifts that are both more portable and less prone to biting. In particular, if you watched this episode and feel in the mood for more incredibly specific animal behaviors, you might like our bucket hat with an orca that’s wearing its own hat. But!

If you want your purchase to arrive anywhere within the US by December 24th with standard shipping, you need to order by December 8th, 2023. Now, if you're watching this video in a different year, it's probably a different date. But if it's this year, then don't forget, December 8th, and don't forget to be awesome. [♪ OUTRO]