In our colleague's excellent article in Bee Culture:
https://www.beeculture.com/winter-management/

 

Mr. Hesbach references another interesting bit of clustering research for
comparison with Mr. Mitchell's work currently under consideration:

 

Collective thermoregulation in bee clusters -
https://royalsocietypublishing.org/doi/10.1098/rsif.2013.1033

 

A handful of interesting tidbits:

 

. we find that the core temperature, defined as the maximum temperature of
the cluster, is higher at low ambient temperatures resulting from
'overpacking'.

 

This observation provides an immediately testable prediction: a cluster may
be 'tricked' into overpacking and overheating its core by warming the bees
just below the surface, while exposing the surface bees to a low temperature
to increase behavioural pressure. As pointed out earlier, experiments and
observations of bee core temperature and bee packing fraction [
<https://royalsocietypublishing.org/doi/10.1098/rsif.2013.1033#RSIF20131033C
6> 6] are consistent with these ideas, although a direct experiment of this
type does not seem to have been carried out. Preliminary analysis of winter
clusters shows that bee density can be written as a function of the local
temperature (A. Stabentheiner 2013, personal communication).

 

Finally, we have also neglected any implications of bee age distribution,
despite knowledge of the fact that younger bees tend to prefer the core and
produce less heat, while older bees prefer the mantle and can produce more
heat [
<https://royalsocietypublishing.org/doi/10.1098/rsif.2013.1033#RSIF20131033C
4> 4,
<https://royalsocietypublishing.org/doi/10.1098/rsif.2013.1033#RSIF20131033C
16> 16,
<https://royalsocietypublishing.org/doi/10.1098/rsif.2013.1033#RSIF20131033C
18> 18]. Accounting for these additional effects will allow us to better
characterize the ecological and possibly even evolutionary aspects of
thermoregulation.

 

Thermoregulation is a necessity for a wide variety of organisms. When
achieved collectively, individuals expend effort at a cost that accrues a
collective benefit. The extreme relatedness of worker bees in a cluster and
near-inability to reproduce implies that the difference between the
individual and the collective is nearly non-existent, so that cost and
benefit are equally shared. However, many other organisms are faced with the
'huddler's dilemma' [
<https://royalsocietypublishing.org/doi/10.1098/rsif.2013.1033#RSIF20131033C
23> 23]; expending individual metabolic effort is costly, and benefits a
group that is only partially related. Because genetic relatedness, metabolic
costs, individual temperature and spatial positions are all easily
measurable [
<https://royalsocietypublishing.org/doi/10.1098/rsif.2013.1033#RSIF20131033C
24> 24], a collective thermoregulatory system is an ideal context in which
to study the tangible evolution of cooperation and competition by building
on our current framework both theoretically and experimentally.

 

 

 


             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html