The Language of Bees

A honeybee colony can contain tens of thousands of individuals, yet it behaves in many ways like a single organism. Thousands of workers must be directed each day to flowers that may be scattered across several square kilometres, and the richest sources of nectar can change from hour to hour as blossoms open and fade. To exploit this shifting landscape efficiently, bees have evolved a remarkable system for sharing information about where food can be found. When a foraging bee returns to the hive after discovering a good patch of flowers, she does not simply rest. Instead she performs a series of movements on the vertical surface of the comb that other bees can follow, and through these movements she tells them roughly where to go. This behaviour, often called the waggle dance, is one of the most sophisticated forms of communication known outside human language.

The dance was decoded in the middle of the twentieth century by the Austrian scientist Karl von Frisch, whose patient observations earned him a share of a Nobel Prize. He noticed that a returning forager traces a figure-of-eight pattern, running in a straight line across the comb while rapidly shaking her body, then circling back to repeat the straight run again and again. The straight portion, known as the waggle run, carries the essential message. Von Frisch showed that the direction and duration of this run are not random but correspond precisely to the location of the food the bee has found.

The direction is encoded through a clever trick. Because the comb hangs vertically inside the dark hive, the bee cannot point directly at a distant flower patch. Instead she uses the angle of her waggle run relative to straight up as a substitute for the angle of the food relative to the sun. If the flowers lie directly towards the sun, she runs straight upward; if they lie thirty degrees to the right of the sun, she runs thirty degrees to the right of vertical. Other bees, crowding around her in the darkness, sense this angle and adjust their own flight accordingly once they leave the hive.

Distance is conveyed separately, through the length of time the bee spends waggling during each straight run. A short burst signals a source close to the hive, while a longer, more drawn-out waggle indicates that the foragers must fly much farther to reach the reward. For very nearby flowers, within a short distance of the entrance, bees often perform a simpler movement in which they merely circle round and round without a clear straight run. This so-called round dance tells the others that food is close by but gives no precise direction, since over such short distances the recruits can easily search the immediate area for themselves.

Direction alone is not enough to make the system work, because the sun moves steadily across the sky through the day. A bee that danced at nine in the morning and again at noon would be pointing at quite different parts of the sky even if she were describing exactly the same flower patch. Bees solve this problem with an internal sense of time that allows them to compensate for the sun's movement. A forager kept waiting inside the hive will gradually shift the angle of her dance to account for how far the sun has travelled while she was delayed, so that the message stays accurate.

The dance is not the only channel of communication in the hive. The quality of the food source is advertised as well, for a bee that has found an especially rich patch dances more vigorously and for longer, attracting more followers than one reporting a poorer find. In this way the colony automatically directs the bulk of its workforce towards the best available flowers. Scent plays a supporting role too: the dancing bee often carries traces of the flowers' odour on her body, and she may share small samples of the nectar she has gathered, giving recruits a preview of what they are being sent to collect.

Scientists have confirmed the meaning of the dance in several ingenious ways. In some experiments researchers trained bees to visit feeding stations at known positions, then watched whether new recruits arrived at the predicted spot. In others, a small mechanical model was used to imitate the dance and successfully sent real bees to a chosen location. Such studies leave little doubt that the movements genuinely carry information rather than merely exciting the other bees at random. The waggle dance remains a striking example of how a creature with a tiny brain can pack a precise, symbolic message into a few seconds of movement, allowing a whole colony to act as if it possessed a shared map of the surrounding countryside.