Dances with Bees

A single honeybee colony typically contains 20,000 to 30,000 bees. At any given time, several thousand female worker bees may be gathering nectar and pollen from food sources spread over an area of up to 40 square miles. The flower patches where bees find nectar and pollen differ not only in distance from the hive and size of the patch, but also in richness -- and a patch's richness decreases as more and more bees forage there. It's clear that without some way for bees to convey information about the distance, direction, quantity, and quality of nearby food sources, the odds of a worker bee finding food would be left primarily to chance.

Over the course of thousands, if not millions, of years, honeybees have evolved an extraordinary form of communication: a behavior that scientists call "dancing." Although honeybee dances -- one called the "waggle dance" and one called the "round dance" -- may seem chaotic to most human observers, researchers have learned to interpret them and are beginning to understand the wealth of information they hold.

Worker bees perform the waggle dance on a special vertical "dance floor," which is located near the entrance of the hive to facilitate quick entry and exit of foragers. Arriving back at the nest, a scout bee with news of food immediately proceeds to the dance floor, where other bees waiting for news gather around her. The scout communicates several key pieces of information during the dance. In the case of the waggle dance, for example, the longer she waggles, the farther the flower patch lies from the hive. The more vigorously she dances, the richer the source of food.

Perhaps most astonishingly, a dancing bee can also indicate the direction of the food source she just visited. The angle her dance deviates from a vertical line shows others the angle they should fly relative to the sun when they leave the hive. In other words, if the food source lies in the same direction as the sun, she will dance straight up along the dance floor (remember that a hive hangs vertically). If the food source is in the opposite direction of the sun, she will dance straight down the dance floor. If the food source lies along a line 20 degrees to the right of the sun, the angle of the bee's movement will be 20 degrees to the right of vertical.

• Why is it advantageous for bees to communicate about food?
• How do you think bees communicate when it isn't sunny?