Communication
A worker does the waggle dance before an attentive
crowd of foragers.
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Honeybees have evolved an extraordinary form of communication
known as the "waggle" dance. It is highly symbolic, separated
as it is in both time and space from the activity it grew out
of (discovering a nectar source) and the activity it will spur
on (getting other bees to go to that nectar source).
When a worker discovers a good source of nectar or
pollen (note the pollen spores dusting this bee's
back), she will return to the hive to perform a waggle
dance to let her nest mates know where it lies.
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A bee performs the waggle dance when she wants to inform other
bees of a nectar source she has found. The waggle occurs on a
special dance floor, which is conveniently located near the
entrance to facilitate quick entry and exit of foragers, and
only bees with news of highly profitable sources of nectar
execute the dance. Arriving back at the nest, a bee with news
to share immediately proceeds to the dance floor, where other
bees waiting for news gather around her. During the waggle,
she dances a figure-eight pattern, with a straight "walk" in
between the loops and a sporadic fluttering of her wings.
The worker communicates several key pieces of information
during the dance. The longer she waggles - typically bees make
between one and 100 waggle runs per dance - the farther the
flower patch lies from the hive, with every 75 milliseconds
she prolongs the dance adding roughly another 330 feet to the
distance. She shows how rich the source is by how long and/or
how vigorously she dances. Perhaps most astonishingly, she
indicates the direction of the source by the angle her waggle
walk deviates from an imaginary straight line drawn from the
dance floor to the sun at its current position. In other
words, if the source lies in the exact direction of the sun,
the bee will walk facing exactly straight up (remember that a
hive hangs vertically). If it lies 20 degrees to the right of
that imaginary line to the sun, the angle of the bee's walk
will be 20 degrees to the right of vertical. Finally, the
dancer shares the odor of the flowers in question with the
other bees, who sample it with their antennae.
Attendees will watch only one waggle dance and only for a
brief period before leaving the hive. In this way, the bee
works for the good of the hive rather than for the good of
herself. If she stayed for the whole dance, she would know
exactly how rich the source is, for instance. But if all bees
waited for the entire dance to take place, and then only went
to the richest sources, the colony would not be maximizing its
use of available resources. This behavior is one of many
instances of how, when it comes to honeybees, natural
selection operates on the level of the colony, not the
individual bee.
With the waggle dance, a worker communicates the
distance, direction, and quality of a nectar-rich
flower patch to her fellow honeybees.
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Honeybees perform two other types of dance. A worker does the
"shake" dance when nectar sources are so rich that more
foragers are needed. A worker arriving back from a foraging
run will move throughout the hive and shake her abdomen back
and forth before a non-foraging worker for one to two seconds
before moving onto more non-foragers at the rate of between
one and 20 bees per minute. The shake dance encourages these
non-foragers to make their way to the waggle dance floor.
Finally, workers do the "tremble" dance when foragers have
brought so much nectar back to the hive that more bees are
needed to process the nectar into honey. Walking slowly around
the nest, the dancer quivers her legs, causing her body to
tremble forward and backward and from side to side. Lasting
sometimes more than an hour, the tremble dance stimulates
additional bees to begin processing nectar.
Photos: ©1998 ORF.
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