Ants hunt for food, but how do they know how to get back? Content warning: Science is messy. Some ants were harmed and we talk about it. Not in great detail, but we thought you should know.
AB: Welcome to bring to them Amy Barton. And I’m trace Kerr and it’s time for a Brain Storm.
TK: So we’re gonna talk about ants. This was an idea that, uh, my daughter’s threw at me the other day because she saw a picture, I think on Instagram. It’s on stilts.
AB: I’m excited already.
TK: Right? Science magazine, 2006. So ants that live in the Sahara desert, they never seem to get lost. You know, they wander everywhere and yet when they find food, so they’re wandering around and these meandering trails, they find some food and then they turn and immediately make a straight shot back to the nest.
TK: Yeah. So scientists had already discovered that there’s ants had one trick up their tiny sleeves and that is that the desert ants seem to memorize the position of landmarks. to keep track of the direction they’re facing. They don’t have a bloodhound sense of smell, but so they’ll find the food and go, okay, mountains are over here. That means, you know, the nest is that way. But then one of the things they wondered is how do they know how far they’ve come? Yes, that’s a legit, how do they know when to stop and you know, to look for the nest. So one theory was they were keeping track of their steps, like a mini ant fitbit. We’ve hit 1400 guys. Time to stop. So they have a some sort of internal step counters. So Matthias Villinger, a biologist at the University of alm and Germany. They set up an ant colony outside the lab and they let 25 ants take a 10 meter trip from the nest and then they collected them. Some of the ants were given stilts on all six legs and I have pictures of this in the show notes. They effectively double the length of their legs. They look like they’re wearing little stilettos, some ants. I know some ants were the control group, so they didn’t do anything to them and they were given food and let go. And the ants that were the control group took their food, went straight back to the nest and they were good. The ants on the stilts walked five meters farther past the nest. Half the distance. More beyond colluded. Yeah, more because they were walking bit longer steps. Oh. And then they stopped and then they looked around for the nest fed.
AB: Bummer dude. What happened?
TK: And then I have to tell you about the third group of ants and I was a little torn about talking about this, but you talked about dropping off worm heads. So um, science is messy. Yes. The third group of ants that made the 10 meter trip, they called them the stub group.
TK: Because while they put stilts on a batch of ants to see if they would walk farther, they amputated the legs half of the legs, like at the knees, another group of ants and he still walk and they could still that. I was thinking, how hardcore are you to get your job done that your legs have been amputated and yet you still pick up your piece of food and you try to walk back to the nest.
AB: They only went five meters?
TK: They went half the distance and then they stopped and looked for the nest and they couldn’t find it. All right. I’m trying to imagine what it’s like to meet Jim, the scientists at a party. What do you do, Jim? Tell me about your work. Well, today I put stilts on ants. Yeah. And Bob over there. He chopped the legs off of them. But here’s the really, this is what caught my attention when I was researching this. Okay. So this was in science magazine, right? And the original paper is titled The ant odometer stepping on stilts and stumps.
AB: The one thing I have learned through our time podcasting for Brain Junk is that scientists have a much stronger sense of whimsy than I expected. Yeah. I love that brainstorm. Wow.
TK: I’m sorry. Ants science had to be done.
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