Ant intelligence; colony actions (Introduction)

by David Turell , Saturday, June 14, 2025, 19:27 (13 days ago) @ David Turell

What each ant does is automatic:

https://phys.org/news/2025-06-swarm-intelligence-longhorn-crazy-ants.html?utm_source=nw...

"Among the tens of thousands of ant species, incredible "intelligent" behaviors like crop culture, animal husbandry, surgery, "piracy," social distancing, and complex architecture have evolved.

"Yet at first sight, the brain of an ant seems hardly capable of such feats: it is about the size of a poppy seed, with only 0.25m to 1m neurons, compared to 86bn for humans.

"Now, researchers from Israel and Switzerland have shown how "swarm intelligence" resembling advance planning can nevertheless emerge from the concerted operation of many of these tiny brains.

***

"'Here we show for the first time that workers of the longhorn crazy ant can clear obstacles from a path before they become a problem—anticipating where a large food item will need to go and preparing the way in advance. This is the first documented case of ants showing such forward-looking behavior during cooperative transport," said Dr. Ehud Fonio, a research fellow at the Weizmann Institute of Science in Israel,

***

"'When we first saw ants clearing small obstacles ahead of the moving load we were in awe. It appeared as if these tiny creatures understand the difficulties that lie ahead and try to help their friends in advance," said Dr. Ofer Feinerman, a professor at the Weizmann Institute, and the study's final author.

***

"Like many ant species, crazy ants are known to alert their sisters to the presence of large food items by laying odor trails: running erratically (hence their 'crazy' name), they touch the ground with the tip of their abdomen every 0.2 seconds to deposit a tiny droplet of a pheromone. This pheromone swiftly attracts other workers to the food. But here, the scientists found this pheromone to play a key role in clearing behavior as well.

"Their observations showed that workers were most prone to clear beads that lay approximately 40mm away from food towards the direction of the nest. They moved these beads for up to 50mm before dropping them, away from the route leading back to the nest. The record holder cleared 64 beads in succession.

"Such clearing behavior always occurred when the pellet was whole, but rarely when it was divided into crumbs. This distinction seemed adaptive, as the observations showed that crumbs were always carried home by single workers, who would simply walk around any beads in their path.

"Intact pellets, however, always prompted 'cooperative' transport by multiple workers, who typically remained stalled by a grid of beads until they were cleared.

"That the beads were a real hindrance was also clear from the time that cooperative transport took to pass through a 5cm by 7cm tunnel: this was 18 times longer when the passage was filled with beads than when it was free of obstacles.

"Further observations also revealed that workers didn't need to be in contact with the food to start clearing behavior: they were prompted to do so by pheromones deposited by foragers. A single mark that happened to be near a bead was sufficient to put a worker in 'clearing mode," after which they would actively look for more beads to clear.

"'Taken together, these results imply that our initial impression was wrong: in reality, individual workers don't understand the situation at all. This intelligent behavior happens at the level of the colony, not the individual. Each ant follows simple cues—like fresh scent marks left by others—without needing to understand the bigger picture, yet together they create a smart, goal-directed outcome," concluded Dr. Danielle Mersch, formerly a postdoctoral researcher at the same institute. (my bold)

"'We find this to be even more awe-inspiring than our initial guess," said Feinerman.

"'Humans think ahead by imagining future events in their minds; ants don't do that. But by interacting through chemical signals and shared actions, ant colonies can behave in surprisingly smart ways—achieving tasks that look planned, even though no single ant is doing the planning". (my bold)

Comment: in the past when when I presented ant rafting I said each ant did as programmed, grabbing the closest ant and holding on, thus making a raft, no new thought involved. This shows the same aspect of colony member actions, automatic behavior creating a whole colony reaction. It is just like soccer or football athletic team efforts, but the human players understand the whole concept of what they are a part.