Queen mating status in social insects is a matter of crucial importance for workers because of its influence
on the queen’s productivity and consequently their fitness. Behavioural and physiological reactions
of workers to the queens mating status have been studied as a proxy to mechanisms maintaining insect
sociality. Here we show that unmated honeybee queens have considerably impaired capacity to trigger
worker sterility and cooperative behaviour in comparison to mated (and thus more productive) queens
and that under unmated queens social harmony in honeybee societies and queen’s dominant position
are somewhat compromised. Together with this it is shown that honeybee workers exposed to unmated
queens despite being active reproductively and behaving accordingly display an impaired ability to
advertise their fertility compared to queenless workers. These findings suggest that reproductive development,
behavioural reactions and production of fertility signals are differentially regulated and differently
influenced by the queen’s presence.