Although they only have about 250,000 neurons compared to our 86 billion, ants can still achieve impressive feats when teamed up. For starters, they’re experts at avoiding traffic jams — a skill we humans could definitely benefit from — and individuals know when to stop to help make their team efforts more successful.
Now researchers have filmed fire ants (Solenopsis invicta), known for their nasty but potentially useful stings, using these skills to smash their way across a sticky surface, forming a bridge to a delicious sausage reward.
Another notable example of tool use in ants is that fire ants “pave” sticky surfaces. I’ve seen signs of this behavior, but didn’t expect it to be this hardy until my friend told me about it (Wang et al., 2021 Insect Science). pic.twitter.com/BaHBmlgtXM
— Horace Zeng (@horacezhl) March 14, 2022
This species of ant is well known for creating bridges made up of their own bodies; they can also transform into floating rafts to survive floods.
They reach their bizarre floating rafts clinging to each other using sticky pads, claw tips, and mouths (with delicate, delicate bites).
Each ant manufactures on average 14 connections with neighboring antsnow floating with bubbles formed using their water-repellent exoskeleton.
Ants also use tools for transporting hard-to-move foods such as liquids. They place debris such as dirt particles and leaves in the liquid, then return the soaking tool to their nest. Others have gone further by using piles of debris and pathways as drains to reduce their risk of drowning.
In a 2020 study, researchers from South China Agricultural University demonstrated that ants can use surrounding debris (in this case, soil particles) to bridge a sticky paraffin-coated surface. But they would do it much more if the food was closer than 20 centimeters (7.8 inches).
“S.invicta searched and transported food on viscose surfaces artificially covered with large amounts of particles, but were unable to carry out these activities on uncovered viscose surfaces or viscose surfaces with few particles “, wrote Chao Wen and his colleagues in their paper.
“However, the ants also covered the treated surfaces without actual food, indicating that the inaccessibility of the treated surfaces, rather than the food, triggered the particle covering behavior. Therefore, they may have developed particle coverage to alter moist or inaccessible surfaces in their foraging territories to forage and transport food, which may have provided them with a competitive advantage over coexisting ant species.”
What’s more, the ants were even able to build a “bridge” of soil over a surface coated with a type of essential balm, believed to be a powerful ant repellent.
University of Georgia entomologist Haolin Zeng highlighted a hardworking worker ant during his fascinating bridge-building post on Twitter.
Here is a worker ant which “tiles” in real time (I put a white circle around it); you can see her picking up the gravel, carrying it on the tape, laying it down and doing it again. pic.twitter.com/zEIEBMmpT1
— Horace Zeng (@horacezhl) March 15, 2022
This ability to transport particles – from glass to dirt – contributes to the important ecological process of bioturbation, the renewal of the underground soil towards the surface. Bioturbation significantly improves the water permeability and fertility of the topsoil.
So, as annoying as these clever little beasts can be when we’re out picnicking or invading our homes, they also provide a huge service to our food culture. Thanks ants – thank you!
This research was published in insect science.