R. Oliver wrote:: "our adaptability pales in comparison to that of the honey bee.  What
with its extremely high recombination rate, polyandry, haplo-diploidy, and
short generation time, the honey bee is designed for rapid adaptation."

I interpret the unique mating system of the honey bee quite the opposite.  

My thesis is honeybees have adopted a strategy of "stasis", and this strategy contributes a further inertia to some of the peculiar features of the super-organism.  Colonies compensate for the genetic "stasis" through behavior and epi-genetics. The mating system is designed to be normative, minimizing drift, polyandry has been both a response and a cause of the bees low rate of evolutionary change. 

The normative pressure on the genome means that selection by humans for agricultural traits needs to compensate for this tendency.

 Honeybees are a broad, freely interbreeding species. Sub-races have developed on islands and mountain redoubts, but none of the wild speciation that characterizes most other insects is present in the eusocial bees-- that is the first piece of evidence that implies the honeybee is a conservative genome.  Very few eusocial bee taxa exist, and that implies the fitness of the model may have found a local optimum, but one that is very hard to repeat and one that is very difficult to shift.   Honeybees represent a complex evolutionary branch that has bred itself into a unique corner, one that is difficult to backtrack out of.

Bee's have coevolved with flowers.  Many solitary bee-flower dyads exhibit very ornate adaptations  to ensure exclusivity.  The solitary bees are consequently fragile organisms with very narrow niches and an inherently high extinction rate.   For example,  consider tongue length/lever position in Salvia-Bee pairs or orchid bee-orchid pollinaria dyads.

Honeybees are broad generalists, opposite of the hyper-specialization one sees in solitary bees.  A flower taxa, competing with a field of other flowers, could lead a co-evolutionary race to deepen its flower and ensure exclusivity in pollination and reward.  The honeybee does not respond to the evolutionary challenge.  HB's lack of response encourages flowers to retain a generalist design.  The broader fitness of this strategy is the Hbees do not fall prey to the local extinction that accompany very narrow niches.

Many plant taxa adopt a chromosome doubling  (polyploid) strategy in response to stress -- which serves to introduce greater adaptive variation into each organism.  Polyandry in HB serves a similar purpose -- the hive has broad array of worker genomes resulting from the promiscuous mating, the hive as a whole has greater fitness from the variation in half-sister workers.  Selection of the alleles that generate this fitness however is made much more-difficult because the undifferentiated egg promoted to be the F1 queen may represent anyone of dozens of recombinations for that single gene, the hives ability to reproduce is only tenuously linked to the genome of the successor queen, and represents more the community fitness in the range of variabilty in the neighborhood.

The geneticists looking at bee immune systems report lower and simpler genetic capacity.  Within-hive variation via the polyandry system has substituted for with-in chromosome variability.  Entropy has resulted in a pruning of alleles and whole genes in absence of selection for its necessity.  Bee's have externalized their variability, but this reduces the heritability of advantageous selections.
Compared to other bees,  Hbees have long generation times (not seventeen year locusts, but queens are long lived). Again this implies that overwintering as adults rather than in diapause is a substitution with trade-offs.  It implies fewer selection chances.  Low selection, low heritability mean real barriers to rapid adaption-- but this extreme "refusal" to speciate is at the core of the honeybee strategy -- in a world where "specialists" have short, fast trajectories and extinction, the hybrid swarm of interbreeding, outcrossing, wildly promiscuous queens just keep doing what they began millions of years ago.

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