Biology Reference
In-Depth Information
100
Fig. 13.14
Worker policing in
the honeybee.
The time course
of worker- and
queen-laid eggs
remaining after
experimental
introduction into
a colony. All
worker-laid eggs
were rapidly
removed. Ratnieks
and Visscher
(1989). Reprinted
with permission
from the Nature
Publishing Group.
Photograph
shows a worker
inspecting and
then removing
(policing) an egg
laid by another
worker. Photo
© Francis
Ratnieks.
80
Queen laid-male eggs
60
40
20
Worker-laid male eggs
0
0
5
10
15
20
25
Hours from introduction of transferred eggs
Tom Wenseleers and Francis Ratnieks (2006a) tested this hypothesis in a comparative
study across 48 species of ants, bees and wasps by examining whether worker policing
was more common in species where queens had greater mating frequencies. As
predicted by kin selection theory, they found that in species where queens mated more
frequently, and hence workers were less related to the sons produced by other workers,
that worker policing was more common (Fig. 13.15).
Worker policing is
both predicted
and observed to
be less common
when queens
mate once
Worker policing and enforced altruism
Should worker policing influence the egg laying behaviour of workers? When policing is
common, this means that any egg laid by a worker is likely to be destroyed. Consequently,
this reduces the relative benefit of producing sons, compared with investing time and
resources into instead helping rear the sons of the queen. Another way of thinking
about this is that policing removes the possibility for direct reproduction and hence
