Data from: Mechanisms for polyandry evolution in a complex social bee

Polyandry in social Hymenoptera is associated with reduced within-colony
relatedness and increased colony-level ecologic fitness. One explanation
for this sees increasing within-nest genetic diversity as a mechanism for
improving group task efficiency and colony competitiveness. A queen on her
mating flight captures nearly 90% of her breeding population’s allele
potential by her tenth effective mating (me~10 males). Under this
population allele capture (PAC) model, colony fitness gains track mating
number in an asymptotic manner, leveling out after about the tenth mating.
A supporting theory we call the genotype composition (GC) model sees
genetic novelty at mating levels higher than the me~10 asymptote, the
hyperpolyandry zone, resulting from unique genotype compositions whose
number are potentially infinite. Colony fitness gains under the GC model
will track mating number in a linear manner. We set up field colonies with
Apis mellifera queens each instrumentally mated with 1, 2, 4, 8, 16, or 32
males, creating a polyandry gradient bracketing the qualitative divide of
me~10, measured tokens of colony level fitness, and collected observation
hive data. Our results lead us to conclude that (1) ancestral colony
traits fundamental to eusociality (cooperative brood care) respond to
mating level changes at or below me~10 in a manner consistent with the PAC
model, whereas (2) more derived specialized colony phenotypes (resistance
to the non-native parasite Varroa destructor) continue improving with
increasing me in a manner consistent with the GC model. By either model,
(3) the mechanism for increasing colony fitness is an increase in worker
task specialisms and task efficiency.