Researchers at Arizona State University have been studying how ants make decisions as a colony. Specifically they looked at how a colony chooses a new nest site, and their findings suggest that the “brain” of the colony is distributed among the worker ants:
“Ants have to reach a consensus if they want to move the colony to a different location,” said [Stephen] Pratt, an associate professor at the School of Life Sciences in the College of Liberal Arts and Sciences. “There are a few key ingredients to how they do this. The main thing is that they have to communicate, and that communication has to say something about how good a site it is.”
“There is a competition going on here,” he said. “There are some ants advertising one site and other ants advertising another. The number of ants visiting and advertising is rapidly growing for the good site. The ants essentially ‘vote’ based on the number of ants visiting a site. If the site reaches a quorum, or threshold, they increase the advertising and basically make a higher level of commitment to that site.”
Click through for thoughts on the queen ant’s role (basically just a baby factory) and for a blurb on the ant robot the researchers are building. Also at the link is a video demonstrating ants that work together cooperatively to carry a “food” object bigger than what a single ant could move.