It's a hard choice, deciding whether ants or bees are Discoblog's favorite kind of wickedly intelligent insect. But if anything could sway the proceedings one way or the other, it's this: Bees know how to do the wave. A study published today in PLoS One suggests that giant honeybees have a kind of collective intelligence that allows them to fend off attacking hornets—a valuable skill, because the bees live in open nests. A team led by Gerald Kastberger of the University of Graz in Austria watched video of 450 examples of "shimmering"—a group of bees flipping their abdomens up and down to create a dazzling visual effect, something like fans doing the wave at a stadium. The bees use this technique at other times, like when one is leaving the nest, but the researchers say they mobilize shimmering en masse when they see a hornet. Kastberger says hundreds of bees can get going in less than a second when a bee-hunting hornet comes around. And the shimmering seems to be an effective deterrent—the hornets usually change course. The researchers suggest that the shimmering waves probably confuse the attacker, and make it unable to fixate upon its intended target. But, they say, the fact that so many bees get in on the act when only a few would do suggests an additional benefit to shimmering: protecting the hive. Shimmering isn't the only clever defensive tactic the giant honeybees use to defend their exposed nests. They also mobilize quickly to launch vicious stinging attacks against birds and other predators. Against wasps they turn to "heat-balling," swarming over the attacker and then heating parts of their body up beyond 110 degrees Fahrenheit, which kills the wasp or hornet. While not an act of aggression like heat-balling, shimmering, Kastberger says, is a way for bees to issues a warning: "We know you're there; buzz off."
Image: Wikimedia Commons/Bksimonb
