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study was apparently due to the much larger number of males contrib-
uting to the inseminations of the queens of the high-diversity group,
generating much more variance than earlier studies, and probably the
more severe and punctuated seasons in Ithaca, New York.
Colonies that are more genotypically diverse have more dance com-
munication, perhaps one reason they are more successful in general.
Pollen-foraging genetic specialists are more ef ective recruiters for
pollen (Section 2.5.7.4). In addition, genetic specialists are more likely
to i nd the resources they are genetically tuned to when they act as
scouts, and they spend more time attending dances for their genetic
bias (Section 5.3.2).
4.4.4 Genotypic Variation Facilitates Graded
Responses to Environmental Change
Another form of the genetic-variation hypothesis for polyandry pro-
poses that colonies that are more genotypically diverse are less likely to
fail because they are more average for their traits. Colonies with less
variability may do better for some traits but fail at others, reducing
their chances to survive and reproduce. But colonies with more varia-
tion do everything at or near the population average, which represents
the historical optimum. We tested 43 colonies with super-sister queens.
Queens were instrumentally inseminated either with four males from
one of four source queens (low diversity) or with one male from each of
the four sources (high diversity; Figure 4.6). Colonies were allowed to
grow in worker population, and then all their food, comb, and brood
were taken away from them, and they were forced to start over. h ey
were observed for 21 days, the time it takes for bees to develop from egg
to adult, and were tested for 19 colony traits. h e experiment was ter-
minated at er 21 days because that was the time at which new bees
could enter the population. So this test represented the ef orts of single
cohorts of bees over 21 days.
Signii cant genetic variation was found for seven traits. Ef ects of geno-
typic diversity were tested by comparing the means of the diverse colo-
nies with the combined mean of the single-drone-inseminated colonies
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