Howdy all,
        Liz maybe quite right!!! It sounds to me that the queen may have
lost her dominance (maybe even died) and the workers ovaries are probably
starting to develop. If this is the case each worker would start to
assert her own dominance. This is usually expressed as workers "mauling"
workers, i.e. bees grasping other bees and attempting to sting but not doing
so. In bumble bee colonies worker dominance manifests itself as oophagy
(eating each other eggs). However, their are socially parasitic bumble
bees (_Psithyrus_ spp.) that do not produce workers, instead the female
will usurp the nest of a host bumble bee (_Bombus_). If the _Psithyrus_
species
is a queen displacer, it either kills or evicts the queen and then the
task of maintaining social harmony falls to the _Psithyrus_ female. Once
the _Psithyrus_ is "accepted" by the host
workers, she must assert behavioural dominance by mauling them (gripping
and attempting to sting without the stinger everted). This
behaviour is also shared by the socially parasitic Yellowjackets. In some
cases their forelegs are adapted for grasping.
 
I hope this was helpful...
 
                                                Cheers,
 
                                                Blair
Blair Sampson
Department of Entomology
Auburn University, Alabama
36849-5413