Biology Reference
In-Depth Information
lab doing research and taking up a new hobby—painting. Deng used
bees from the high and low strains to test for foraging ei ciency. Unfor-
tunately, she dropped out of science at er completing her doctoral de-
gree and never published her results in scientii c journals. However,
they are contained in her doctoral dissertation at the University of
Miami.
Queens of the high and low strains were instrumentally inseminated
with sperm from a single drone each, derived from their own strain.
h e queens laid eggs in combs that were then placed together in a com-
mon nursery colony until larval development was complete. h e nurs-
ery colony was a wild-type (not high- or low-strain) colony that was set
up to raise the brood from eggs to pupae. h e combs containing pupae
were transferred to an incubator maintained at normal brood-nest
temperature (about 35 degrees Celsius) where workers from each strain
emerged into separate cages. Newly emerged workers of each strain
were divided into two equal groups, marked with paint for strain iden-
tii cation, and placed in two host colonies. Each host colony received
high- and low-strain workers. We call this our “common-garden ex-
periment” (Figure 4.5). We wanted the marked “focal” bees to be in the
minority in the hive because otherwise they might signii cantly af ect
the stimulus environment of the nest and, therefore, the behavior of the
focal bees.
h e two host colonies were placed in separate cages in the same in-
door l ight room. One host colony was of ered only 50 percent sugar
solution in its cage as a foraging resource, while the other was of ered
only freshly ground pollen. Bees foraged for these resources in the cage.
When paint-marked workers began foraging, they were individually
marked by gluing a numbered plastic disk onto the thorax. Bees were
observed for three hours per day during their entire foraging lives.
Nectar load weights were determined for each forager once each forag-
ing day by placing a nectar feeder on an analytical balance and record-
ing the net loss of weight from the feeder for that trip. Average load
weights were determined for each forager of each strain, and the strain
average was determined as the average of the individual averages. Pol-
len load weights were not determined because collecting pollen from
