BoundedRationality_TheAdaptiveToolbox.pdf

258 Thomas D. Seeley
ceased their dancing; only a minority (24, or 33%) switched their dancing. Thus
we had a very curious result: the process of building a consensus among the
dancing bees relies much more upon bees ceasing to dance than upon bees
switching their dances to the chosen site. In other words, in a honeybee swarm,
consensus building is more a matter of those favoring the losing option dropping
out of the debate than it is a matter of them changing their minds. The former
seems a good deal simpler than the latter.
When we next examined the behavior records of those relatively few (24) individuals
that did switch their dancing from the nonchosen to the chosen site, we
found a hint that even these bees were doing something simpler than one might
think at first: all had a long period (2-10 hours) between stopping dancing for
the nonchosen site and starting dancing for the chosen site. It looked, therefore,
like these bees did not quit dancing for the nonchosen site by encountering a
"persuasive" dancer for the chosen site and then comparing the two sites. Instead,
it looked like these bees switched their dancing by first losing the desire to
produce dances for one site and then, several hours later, gaining the desire to
produce dances for anothert site, one that they probably visited after following a
dancer advertising this second site. (By this time, all the dances on the swarm
were advertising the chosen site, hence when these 24 switching bees resumed
their dancing, they all did so with dances for the chosen site.) This finding suggested
that the phenomenon of a bee switching her dancing between sites may
not be based on her having knowledge of multiple sites simultaneously and comparing
the sites ("comparison tactic"), but may instead be based on her having
knowledge of just one site at a time ("noncomparison tactic"). A conclusive test
of these two hypotheses remains to be done; however, for now it is useful to recognize
that the cognitive tools underlying the phenomenon of dance switching
may be simpler than they appear at first glance.
If all of the bees that initially dance on a swarm eventually cease dancing, and
if most bees that subsequently dance on a swarm start dancing after following a
dancer chosen at random, then it is not hard to see how a consensus will emerge
among the dancing bees. All sites will eventually lose their old supporters, and
only those sites that elicit strong dancing will gain new ones. In addition, because
strong dancing for a site recruits many bees to this site, and because these
recruited bees will also dance strongly for the site, there is positive feedback on
the number of bees at a site. Eventually, the site that most strongly stimulates
bees to dance will become the target of all the dances. But what ensures that the
consensus will settle on the best site, or at least one of the better sites, in the array
of alternatives discovered by the scout bees? One mechanism for achieving this
would be for the bees to adjust dance strength in relation to site quality, so that
the higher the nest-site quality the greater the waggle-dance strength.
There is evidence now that scout bees that have visited an excellent site will
indeed produce dances that contain more waggle runs than do bees from a mediocre
site (Seeley and Buhrman, unpublished results). They accomplish this by