Biology Reference
In-Depth Information
hives and collected all the undertakers. h e colonies consisted of three
subfamilies of bees (derived from three fathers used to instrumentally
inseminate the queens) that were identii able with allozyme markers.
All undertakers were captured as they dragged bodies out of the hive,
and their subfamily membership was determined by allozyme analysis.
Our prediction was that some subfamilies would be more likely than
others to remove the dead bees; that is, they would have genotypes that
made them more responsive to the dead-bee stimulus. h is prediction
was coni rmed. However, we predicted that with 1,000 dead bees, the
response thresholds of bees across all subfamilies would be exceeded,
and the biases observed with the low stimulus would be eliminated.
h at was not the case. h e same biases were observed with the high
stimulus. h e workers did not show plasticity for undertaking; instead,
they were “constrained” by their genes. We also failed to see plasticity
at the colony level. Repeated sampling depleted the undertakers in the
hive such that the time to remove the dead bees increased signii cantly,
and it took several days to return to the initial rates of removal. h is
suggested that there was a i nite number of undertakers composed of a
nonrandom genetic sample of bees.
3.8.4 Canalization of Behavior by the Environment
Bees that live together in a nest share common colony environments
and experiences. If behavioral responses are “tuned” by the environ-
ment or the “needs of the colony,” then the outcome will be a decrease
in variation among workers for their response thresholds, measured by
their response probabilities. h e common environment will make them
more similar; it will canalize behavior. h e genotype of an individual
places constraints on her plasticity and maintains dif erences among
workers in genetically variable colonies. Nick Calderone denied bees
early social experiences by putting them in cages in an incubator for 6
or 12 days (Figure 2.14). He recombined them with bees from the same
age cohorts that had resided in the hive and compared their behavior.
h e bees were from the high- and low-pollen-hoarding strains of
Hellmich and Rothenbuhler and were known to dif er in their foraging
