Agriculture Reference
In-Depth Information
Competition from other laying workers is intense, and a clear sign of this laying-worker
syndrome is the sight of several eggs in a cell. These eggs will often be placed halfway
down the cell due to the shorter length of the worker's abdomen. If at this stage another
queen bee is introduced to the colony, the laying workers will invariably kill her (dealing
with this problem is examined in Chapter 8).
The 'waggle dance'
Bees are such efficient pollinators because, as forager bees, they can communicate the
source of food to each other. Immediately on setting up as a colony, scout bees are out
looking for the nearest and best sources of nectar and pollen. When they find these, they
return to the nest with samples and tell the other foragers about the location and how to
get there using a highly symbolic dance language based on movement and sound.
Performing the 'waggle dance'
What is known as the 'waggle dance' has been studied by scientists for decades, and it
is generally believed to be the method by which bees tell one another of the location of
food and potential new nest sites. The dance takes the form of a figure of eight and is
performed by worker bees on the vertical surface of a comb (see Figure 4). The worker
moves along a straight line in the figure of eight and waggles from side to side. When
this waggle phase is complete, the bee circles to one side and returns to the starting
point. This sequence is then often repeated over 100 times, with the direction of the
return phase circling alternating each time.
The duration of the waggle phase is correlated to the distance of the food source and
the number of cycles performed is correlated to the size of the food supply. The further
the foraging site, therefore, the longer the duration of the waggle, and the bigger the
food source the greater the number of dance cycles. The angle of the straight line from
the vertical (vertical comb) is equal to the angle between the food source and the sun
upon departure from the hive, and the vigour with which the waggle is performed is an
indication of how much food is present at the site.
While carrying out this dance routine, the bee will often stop and give out small
samples of nectar to those attending the dance. The attending bees gather a great deal
of information from this dance, such as how far away the nectar is, the direction of
