During these dances, bees produce a characteristic sound with their wings and simultaneously transmit the odor of the nectar whose location they wish to communicate. The receiver bees remain in contact with the dancer. These dances, performed on the combs, are all the more vigorous and long-lasting when the nectar is abundant and rich in sugar; they also provide information about which plants are no longer productive and which are becoming so. Alerted in this way, previously inactive bees take flight in search of this food source. Thanks to these communication mechanisms, colonies are able to adapt and efficiently locate available food sources.

The description of what he termed the “language of bees” and the understanding of bee “dances” are owed to the Austrian ethologist Karl von Frisch (1886–1982), notably in his work The Dancing Bees. His theory, supported by the work of his student Martin Lindauer, was confirmed in 1986 using a miniature robot capable of performing the bee dance.

Types of dances

When the scout performs a round dance (round dance (en)) on the wax combs in the darkness of the hive, she indicates that the nectar source is nearby, within a radius of less than fifty meters. The discoverer traces a circle by turning rapidly on herself—eight to ten turns in fifteen seconds—then performs a half-circle in the opposite direction, often changing the direction of rotation during this type of dance. Other bees, which follow the dancer and touch her with their antennae, detect the scent of the nectar source with which her body is impregnated and then leave the colony in search of the food source, guided by the odor of the flowers to be exploited. This type of dance does not convey directional information1.

On the vertical combs of the hive, the angle formed between the vertical and the axis of the figure-eight indicates the direction to follow relative to the solar azimuth.

When a bee performs a waggle dance, she indicates a food resource located at a greater distance. In this case, the forager orients herself relative to the direction of the sun: in addition to her two compound eyes, she has three ocelli on the top of her head—simple eyes sensitive to polarized light—which allow her to locate the sun even through clouds.

The scouting bee traces a short straight line, then a half-circle, returns to her starting point, traverses the diameter again, performs another half-circle on the other side, and repeats the sequence. During the straight runs, the dancer’s body is inclined forward, her legs firmly in contact with the substrate, and she waggles rapidly, like a pendulum. By following the dancer, other bees recognize the odor of the flower species to be explored and also obtain information about the direction of the resource and its distance from the colony. The waggle dance is faster the closer the food source is (nine to ten complete “figure-eights” in fifteen seconds when the source is at one hundred meters, seven at two hundred meters, four and a half at one kilometer, and only two at six kilometers²), and the angle between the vertical and the axis of the straight dance corresponds to the angle between the direction of the sun and that of the food source. As the sun moves across the sky, the dancer adjusts the angle of her dance accordingly.

On vertically arranged combs, the forager behaves in a similar manner but performs a slightly different dance: she begins by tracing a half-circle, then returns to her starting point along a straight line—the diameter; upon returning, she traces the other half-circle in the opposite direction and again traverses the same diameter in the same direction. This cycle, whose shape resembles a figure-eight, is repeated many times. While traversing the diameter, the bee waggles by moving her abdomen laterally.

Waggle dance (“figure-eight”), the undulations symbolize the waggle (movement according to the arrows)
Indication of a nectar source located 60° to the right relative to the direction of the sun
Indication of a nectar source located 150° to the right relative to the direction of the sun

The direction of the diameter indicates that of the food source. Imagine a dial with the hive at the center and the sun positioned vertically above it. On this dial, the bee moves from the center toward the food source. If the food source lies in the direction of the sun, the bee moves vertically upward along the straight line. If the source is located 30° to the right of the sun’s direction, the straight line traced is inclined 30° to the right of the vertical and is traversed from bottom to top. If the nectar flow lies opposite the sun, the path is then from top to bottom.

The distance of the nectar source is indicated by the number of lateral movements of the abdomen during a vibrating phase, or by the duration of this phase (an equivalent measure): the greater the number of movements, the farther away the food source.

The quality of the food source is indicated by the speed of the return during the half-circles performed without wagging. Conversely, the forager emits a “stop signal” (a mechanism of negative feedback) to warn the colony of danger (for example, if she has been attacked by a predator, has detected stress pheromones on flowers, has fought with bees from other colonies and been defeated, etc.)³.

In 1951, Martin Lindauer deciphered another mode of bee dance, known as the “nest-site dance” or “swarm dance”: once a year, for a few hours or days, a waggle dance is performed by scouts outdoors on the backs of bees that have settled as a swarm on a branch after leaving their former nest to choose a new one⁴. As the colony grants scouts the authority to decide on this choice, this process is considered equivalent to a form of delegated democracy⁵, since mechanisms of positive and negative feedback reveal genuine opposing debates during this decision-making process⁶.

 

 

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