Swarm Savvy: How Bees, Ants and Other Animals Avoid Dumb Collective Decisions

Article excerpt

This is a phone conversation, so if Tom Seeley rolls his eyes, that's his business. He's a distinguished behavioral biologist, full professor at Cornell University, member of the American Academy of Arts & Sciences and so on. Yet he takes it pretty well when asked whether honeybees could have had a real estate crisis and crashed their banking system.

Seeley, at least voice-wise, stays polite and treats this as a serious question. Which it is.

Of course honeybees don't have a banking system, but they do exhibit collective behavior. The queen bee doesn't decide what the colony needs to do. Instead, each colony member does her or his bee thing, and out of hundreds or thousands of interactions, a collective decision emerges. Seeley's next book, due out in 2010, will be called Honeybee Democracy.

Bees, ants, locusts and plenty of other animals collectively make life-or-death choices. The biologists studying animal groups are finding strange lab fellows these days in economists, social scientists, even money market specialists. They are trading tales of humans and of nonhuman animals to understand collective behavior and what makes it go right or wrong.

"There is a new excitement in this whole field of decision making these days," says ant biologist Nigel Franks of the University of Bristol in England. Franks and Seeley organized a multidisciplinary conference on collective decision making held in January at the Santa Fe Institute in New Mexico. And both biologists contributed to a special issue of Philosophical Transactions of the Royal Society B (March 27) on the same topic. The issue considers insects as well as the European Parliament.

Even compared with gatherings of diplomats in bespoke suits, bee nests and ant colonies have plenty to contribute to the field. "The really lovely thing is that we can take these things apart and put them back together again, and we can challenge them with different problems," Franks says. Seeley notes that studying honeybees has taught him a lot about how to run faculty meetings.

All but the darkest view of university professors credits them with more cognitive power than can be found in the minuscule brains (sorry, bees) of insects. So one might wonder how well collective wisdom works for nonhuman animals.

That question is what makes the research so intriguing. Bee colonies have been making collective decisions for about 30 million years, Seeley says, "so they've had lots of chances for failing systems to get pruned out by natural selection." Bees have unique needs of course, but when it comes to real estate (alas, humans), bees almost always get it right.


The human hive

To be fair, today's research on these successful insects draws from studies of the first animal to be analyzed in detail for collective wisdom: Homo sapiens.

In the 18th century, Marie-Jean-Antoine-Nicolas de Caritat, marquis de Condorcet, welcomed the French Revolution and used mathematical probabilities to argue for the virtues of shared decision making. Known today as Condorcet's jury theorem, his work describes conditions in which members of a group voting by majority rule are more likely to render a correct choice between two alternatives than is any individual in the group. One of the critical conditions for a happy outcome, the Marquis contended, was that each group member vote independently rather than copy another (possibly mistaken) juror.

Human groups deciding as a whole have scored spooky triumphs. "Nearly everybody is miles out, but when you take the average of these guesses, they're usually very, very accurate," says Ashley Ward, a fish behaviorist at the University of Sydney in Australia, whose work is cited in the special Transactions issue. The idea goes by the name "many wrongs," as in many wrongs make a right.

A classic example appeared in Nature in 1907. …