Ants share decision-making, lessen vulnerability to 'information overload'

Sep 24, 2012
Temnothorax rugatulus. Credit: Arizona State University

Scientists at Arizona State University have discovered that ants utilize a strategy to handle "information overload." Temnothorax rugatulus ants, commonly found living in rock crevices in the Southwest, place the burden of making complicated decisions on the backs of the entire colony, rather than on an individual ant.

In a study published in the early, online version of scientific journal , Stephen Pratt, an associate professor in ASU's School of in the College of Liberal Arts and Sciences, and Takao Sasaki, a graduate student in Pratt's lab, suggest that the key to preventing cognitive overload is found in -making, rather than in .

"I think the reason people are interested in this is because as humans, we can become overloaded with information—and that can possibly be detrimental both to our health and to how effectively we make decisions," Pratt said. "There's a sense that as a society, we are being more and more overwhelmed by information."

Previous research has shown that have the ability to compare the quality of two potential nest sites—even if no single ant visits both sites. Pratt and Sasaki hypothesized that a colony could choose a high-quality nest from many more options more effectively than individual , because each member of the colony assesses only a small part of portion of available sites, and then shares the information with the entire colony.

"People usually think of ants as sort of stupid, that they can't really compare options, or that they don't have good cognition," said Sasaki. "But actually, individual ants can compare options, and that's why they too experience cognitive overload—a well-documented in human beings."

The pair designed experiments with artificial nest sites to evaluate the ants' decision-making abilities. Both colonies and individual ants were given two levels of tasks. Ants had to choose between two nests, or they had to choose among eight nests. In both experiments, half the nests were unsuitable. Nests are frequently chosen based on entrance and cavity size, as well as darkness and other features.

Researchers discovered that individual ants made much worse decisions when faced with eight options rather than two, meaning that they experienced cognitive overload. Colonies, on the other hand, did equally well with either two or eight options, showing that they could handle the harder problem as a collective.

The study shows what Pratt believes to be the answer to two questions: What do you get out of being a collective intelligence? And secondly, why and how is a group smarter than an individual?

"Living in a group is costly in many ways, so ants must get some benefit from doing it," said Pratt. "By sharing the burden of decision-making, colonies avoid the mistakes that a solitary animal makes when taking on too much information. What's great about these ants is that we can see exactly how they do this, by making sure that no ant has to process more information than it is able to."

Pratt added that this is one problem ants can solve, but that there are other problems ants face that we might be able to learn from.

"What we really want is a more complete understanding as to how this society works as a kind of distributed brain," Pratt said. He believes their research may provide insight into how to handle information excess in society and will have applications in collective robotics.

Explore further: Hormone analysis helps identify sexual receptivity of female rhinos

Related Stories

Ants more rational than humans

Jul 24, 2009

In a study released online on July 22 in the journal Proceedings of the Royal Society: Biological Sciences, researchers at Arizona State University and Princeton University show that ants can accomplish a task ...

Ants compete, recruit to identify best colony (w/ Video)

Nov 04, 2010

(PhysOrg.com) -- Professor Stephen Pratt studies how small ant colonies pick a new nest when theirs is destroyed or is no longer viable, and has found that the "brain" of the colony is distributed throughout ...

How house-hunting ants choose the best home

Apr 22, 2009

(PhysOrg.com) -- Direct comparison of alternatives isn’t always the best way to make a decision - at least if you’re an ant. House-hunting rock ants collectively manage to choose the best nest-site without ...

Ant’s social network similar to Facebook

Apr 14, 2011

(PhysOrg.com) -- A recent study in the Journal of the Royal Society Interface presents findings that show that not all ants are as social as others. Similar to your friends on Facebook, some ants communicate with o ...

Recommended for you

Calcium and reproduction go together

14 hours ago

Everyone's heard of the birds and the bees. But that old expression leaves out the flowers that are being fertilized. The fertilization process for flowering plants is particularly complex and requires extensive communication ...

User comments : 3

Adjust slider to filter visible comments by rank

Display comments: newest first

HannesAlfven
1 / 5 (1) Sep 24, 2012
Why restrict this finding to robotics? We experience information overload in science as well ...
Eikka
5 / 5 (1) Sep 24, 2012
Why restrict this finding to robotics? We experience information overload in science as well ...


To hide the fact that a small number of representatives, or a single president wielding great power over the entire society isn't necessarily optimal, and that political and economic power should be distributed further down the chain.
JoeBlue
1 / 5 (2) Sep 24, 2012
To hide the fact that a small number of representatives, or a single president wielding great power over the entire society isn't necessarily optimal, and that political and economic power should be distributed further down the chain.


We don't need the science to tell us that it's an inherently bad idea to give that much power to so few people. Individuals with enough capability to handle that sort of responsibility are rare enough. One's with Integrity and Principles are even rarer.