Passage IV

NATURAL SCIENCE: This passage is adapted from Milions of Monarchs, Bunches of Beetles: How Bugs Find Strength in Numbers by Gilbert Waldbauer (@2000 by the President and Fellows cf Harvard College).

Cooperation between workers in a honey bee colony makes them the champion insect discoverers and exploiters of resources: especially pollen and nectar, almost their only foods: but also nesting sites water to air condition their nests; and plant gums to seal cracks in the nest. Because the workers in a honey bee colony cooperate with each other, they can efficiently utilize the various sources of pollen and nectar in their territory, synchronizing their efforts to coincide with sources that are constantly shifting in time and space. The plants in a patch will yield pollen and nectar while they are blossoming but will be useless when the blossoms fade. Honey bee colonies are likely to exploit several kinds of pollen and nectar plants at the same time, but if a colony is to survive and prosper, it must constantly find new food sources to replace others that become unproductive.

Honey bees live in large, complex, and highly organized societies, probably the most advanced of the insect societies, and among animals other than insects, exceeded in complexity only by human society. But honey bee and human societies are fundamental different. A human community with a population of 50,000 consists of people and family groups that are usually not related to each other. A honey bee colony may include 50,000 individuals, but it is a huge family unit, all of its members the children of one queen.

A honey bee colony is, for two major reasons, exquisitely prepared to exploit with maximum efficiency the pollen and nectar sources in its territory, which often encompasses as much as 43 square miles. First, the colony constantly sends out workers that scout for new sources of pollen and nectar. Second, when a successful scout returns to the nest, she uses the "dance language of the bees," more precisely the waggle dance, to communicate to her sister workers the exact location of the new resource. The language of the honey bees is one of the most astonishing marvels of nature. Until Karl von Frisch deciphered the meaning of the waggle dance early in the twentieth century, no one even dreamed that one insect could communicate complex information to another insect.

The waggle dance is performed on the vertical surface of one of the waxen combs that hangs in the dark interior of the nest. Well described by Thomas Seeley in Honey Bee Ecology and The Wisdom of the Hive, the dance is in the form of a figure eight. The scout begins by making a straight-line run, the crossbar of the eight. She then turns to the right and loops back to the beginning of the crossbar and makes another straight-line run along its path. Then she loops to the left and again returns to the beginning of the crossbar. She has now described a figure eight and repeats this pattern time after time, wage ling her abdomen from side to side and emitting a high-pitched squeak as she moves along the crossbar. As she dances. other workers crowd in close, touch her with their antennae, and follow her through the movements of the dance.

The straight-line waggle run of the dance conveys two crucial pieces of information, the distance to the new resource and the direction in which it lies. The distance is conveyed by the waggle run's duration——the longer it takes, the more distant the flowers. The direction is expressed——quite accurately——as a deviation from a straight line from the nest to the sun. Just as we follow the convention that the top of a map represents north, honey bees follow the convention that the top of he comb symbolizes the direction of the sun. Thus when a worker conveys the direction of a food source that is directly opposite the direction of the sun, she directs the waggle run straight downward. If its direction is directly toward the sun, her waggle run goes straight up the comb. If the direction is 50 degrees to the left of a straight line from the hive to the sun, the waggle run is directed 50 degrees to the left of the vertical axis of the comb.

The workers that have allowed the scout's dance then fly to the new patch of blossoms. If they are successful in their quest for pollen and nectar, they return to the hive to repeat the dance and recruit more workers. If the patch of blossoms is not productive, they do not to repeat the dance. As long as the source continues to be productive, more and more workers will forage there and dance to recruit yet more workers. In this way, the foraging activity of the colony is focused on this patch and probably a few other productive patches of blossoming plants.