Think Twice before Squashing Ants-Their Colony Might Remember You

Ants don’t exactly have a hive mind to see and remember everything, but they do have something called “swarm intelligence,” where ants leave temporary pheromone trails if they find something interesting like food or encounter a different colony and want to notify their nestmates.

While ants are naturally aggressive towards unfamiliar colonies, they become even more hostile if they recognize their opponents. If the ants have enough time to “get to know” another colony, they must be within foraging distance and are likely a threat to survivalhood.

Ants recognize their nestmates by the unique scent of their colony. Since this scent changes over time, ants must continuously update and “relearn” their recognition patterns.

Researchers from the University of Freiburg, Germany, investigated how ants formed these behaviors. They think ants may be able to learn associatively by creating connections between the attacker and their smell.

Dr. Melanie Bey and her team took several focal ants and introduced them to foreign ants-ants from another colony. Over the course of five repeated sessions, they found that the focal ants were increasingly hostile towards the foreign ants.

The researchers dubbed this the “nasty neighbor effect,” where ants are more hostile toward familiar ants. If those foreign ants were also antagonistic, focal ants associated the particular smell of that colony with aggression.

This way, ants can meet repeat attackers with preemptive aggression, and any other ants from that colony would be labeled as a threat and dealt with accordingly.

Interestingly, aggression levels didn’t depend on how long the encounters lasted. In follow-up experiments, the researchers reduced the exposure time from five days to just 45 minutes-but the focal ants still displayed heightened aggression. As long as there was some exposure, focal ants were aggressive towards the familiar opposing colonies.

The seemingly simple findings hold a key importance: associative learning plays a role in generating nestmate and non-nestmate templates. Recognition of non-nestmates can improve through exposure and experience with these colonies.

Individual ants have no way of communicating their learned associations to the rest of the colony. This means nestmate defense behavior can vary from one ant to another based on their personal experiences.

However, the exact quantity or change in aggression was not the focal point of the study. “Dedicated experiments would be needed to properly dissect these effects,” the study claims.

See more on: Current Biology (Journal)

Originally published at https://tanayvenkata.substack.com.