Ectotherms usually require a narrow range of thermal conditions for development; thus, parental selection of oviposition sites is crucial. In a field experiment, we investigated female solitary red mason bee (Osmia bicornis) preferences for potential nest site temperatures and their effects on offspring development. The results showed that bees detected and avoided nest sites with high temperatures (28°C) and often chose cooler (24°C) or ambient temperatures (average 18–20°C). This is a protective behaviour because offspring survival decreases with increasing nest temperature, mostly due to mortality at the egg stage. Elevated temperatures also led to weight loss in adult bees. However, hot nest temperatures appeared to deter adults or kill parasite larvae, as the highest numbers of parasites were observed in unheated nests. We concluded that choosing the proper temperature for nests is an important element in bee life strategies, especially in warming environments.

Worker honeybees may reproduce in either their own or foreign colonies; the latter situation is termed intraspecific reproductive parasitism (IRP). In this study, we compared the tendency for IRP between normal honeybee workers, which are characterized by a relatively low reproductive potential, and “rebel workers”, a recently discovered subcaste of honeybee workers characterized by a high reproductive potential that develops when the colony is without a queen. We expected that the high reproductive potential of the rebel workers would influence their reproductive strategy and that these individuals would drift to other colonies to lay eggs more often than normal workers. The results confirm our expectations and show that rebel workers are more likely than normal workers to drift to foreign colonies. The rebel workers also preferred to drift to queenless colonies than to queenright colonies, while the normal workers did not show this preference. This study indicates that rebel workers have a tendency for IRP, which may be responsible for the maintenance of the rebel worker strategy in bee populations.

The honeybee continues to be developed as a model species in many research areas, including studies related to the effects of alcohol. Here, we investigate whether workers display one of the key features of alcoholism, namely withdrawal symptoms. We show that workers fed for a prolonged time on food spiked with ethanol, after discontinuation of access to such food, exhibited a marked increase in the consumption of ethanol and a slight increase in mortality. We additionally show that withdrawal symptoms do not include an increase in appetitiveness of ethanol diluted in water. Our results demonstrate that workers can develop alcohol dependence, which might be especially important in the natural setting of repeated exposure to ethanol in floral nectar and for their potential as a model of alcohol addiction.

A recent study showed that worker larvae fed in a queenless colony develop into another female polyphenic form-rebel workers. The rebel workers are more queen-like than normal workers because they have higher reproductive potential revealed by more ovarioles in their ovaries. However, it was unclear whether eggs laid by rebel workers avoided worker policing. Worker-laid eggs are normally eaten by other workers in a queenright colony. The aim of this study was to compare the survival of three classes of eggs, namely, those laid by normal workers, rebel workers, and the queen. All eggs were tested in queenright colonies. We expected that rebel workers would avoid policing by laying more queen-like eggs. Contrary to our expectations, eggs laid by rebel workers were eaten by other workers, as were eggs laid by normal workers, and only a few worker-laid eggs (both normal and rebel) survived for more than 3 h. Therefore, in a queenright colony, eggs laid by rebel workers do not avoid policing.

Among the honeybee workers, extranidal foragers are more rhythmic in their diel activity and more likely to encounter alcohol than intranidal nurses. Foragers are more active and potentially exposed to alcohol during the day, while nurses work around the clock and probably never encounter alcohol. Here, we took advantage of these differences and checked for a connection between the effects of alcohol and period of the day. We hypothesized that foragers would show higher intoxication resistance to alcohol than nurses during the day. Furthermore, we hypothesized that only in foragers the intoxication resistance to alcohol would be different between day and night. We detected higher intoxication resistance to alcohol in older, forager‐age bees, than in younger, nurse‐age bees during the day, which confirmed the first hypothesis. However, the intoxication resistance differed between day and night in both worker types, which provided no support for the second hypothesis. Surprisingly, we found the intoxication resistance to be highest during the night in both types of workers. Reported differences in the intoxication resistance showed no relation to differences in alcohol absorption between day and night, thus the exact mechanistic explanation for the diel oscillation in alcohol influence on bees remained unclear.