Honeybees give directions by dancing, using the sun as a compass.
A forager bee that finds good flowers returns to the hive and runs a figure of eight on the vertical comb. The angle of her waggling run from straight up matches the angle between the sun and the food; how long it lasts encodes distance. The Nobel laureate Karl von Frisch was among the first to decode it.
Each circuit of the dance has two parts: a straight 'waggle run', in which the bee shakes her body, and a loop back to the start, alternately to the right and the left, tracing a figure of eight. A dance can run from one circuit to more than a hundred. For food lying directly towards the sun, the waggle run points straight up the comb; food 40 degrees to the right of the sun means a run 40 degrees right of vertical. The farther away the food, the longer each waggle run lasts. Bees that dance for a long time even adjust the angle as the sun moves.
For food close to the hive, the performance becomes a simpler 'round dance'; in one Italian honeybee subspecies, the full waggle dance appears only for food more than about 40 metres away. Dancers also release particular chemical compounds and give off electric fields that may help followers pick up the message. More excited bees waggle faster, and rival dancers compete, sometimes disrupting each other. When researchers placed a dead bee on a flower, returning foragers danced far less, as if weighing up the risk of a predator.
How much other bees actually use the directions is debated. In one experiment, 93 per cent of foragers that closely followed a dance went back to places they already knew instead. Bees can also find food by scent and memory, and tend to switch to dance directions when their own information stops paying off. The dance seems to matter much more in the tropics, where flowering trees are rich but scattered and short-lived, than in more uniform temperate landscapes; in some settings its directions are used only about ten per cent of the time.
The behaviour may have started as a way to choose new nest sites rather than food. Species that nest in the open dance on a horizontal surface under the sky, while those nesting in dark cavities dance on vertical combs, using gravity as their reference and adding buzzing sounds. Species even have their own 'dialects', and in one mixed colony Asian and European honeybees gradually learned to understand each other. The dance has inspired computer routing algorithms, and the Zigbee wireless protocol is named after it.
Source: Wikipedia — Waggle dance · Text summarised from Wikipedia (CC BY-SA 4.0)
