Sunday, May 18, 2008

Does Natural Selection Act On Honeybee Colonies?

Thomas D. Seeley in the intro of his book "honeybee ecology", points out that various situations result in individual workers competing with each other rather than cooperate in the nest, and there is no evidence of colony level selection. Selection is on individuals and because of the unique genetics of honeybees this often coincides with the interests of the colony as a whole.

but i thought of this: the first question is what would be a unique hereditary component for the colony as a whole? as the workers have on average about 11 parents! their mother mates with 10 guys on average, so the workers are a very mixed population.

it dawned on me that the NEST itself cold be a part of their heredity! If scout bees preferentially choose new nests that are reminiscent of their old nest, this would be an example of cultural transmission in honeybees! and it would be a heritable feature of colonies as a whole (all the bees share it) that can be selected for, after all choice of nest characteristics could play strong role in survival of colony. and different lines of honeybees might preferentially choose different kinds of nests!

i like it. now to find data to see if colonies choose similar nests as their old ones.

I'm talking about cultural transmission, the
'type' of nest they like is STORED in the nest itself, as we might store culture in an library. this bit of culture might be passed on by memory, the scout bees looking for the next nest remember their old nest and choose a similar one.

the nest is a composite of a LOT of choices: hight above ground, internal volume, entrance characteristics, humidity, surroundings... These effect the evolutionary success of the colony. they are factors that can be selected for and against regardless of the 11 odd genotypes an average colony posseses.

seeley says that scouts spend an hour each crawling the walls of the cavity then flying around it outside then crawling then flyiing till they synthesis a lot of info about it. he says they are selecting sites based on at least 6 or 7 parameters! when the scout comes back to the swarm and does his waggle dance about the site somehow he synthesizes all this motion into the dance i THINK! i really got to go watch.

and about 100 scouts are doing this nest site selection! some large fraction of these scouts finally visit the winning site before they all fly to it. these scouts have spent about 30 days plus overwintering in the old nest site so know it well. bees have good memory! they can even remember flower patches over winter. they can remember what times of day half a dozen patches come into their nectar flow and go to them at the right times...

thus i say if scouts DO choose nests like their old ones, this is a source for selection at the COLONY level, as opposed for selection of one of the 11 genotypes of the competing workers in the nest.

bees are the bees knees!

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