Increased survival of honeybees in the laboratory after simultaneous exposure to low doses of pesticides and bacteria.

Recent studies of honeybees and bumblebees have examined combinatory effects of different stressors, as insect pollinators are naturally exposed to multiple stressors. At the same time the potential influences of simultaneously occurring agricultural agents on insect pollinator health remain largely unknown. Due to different farming methods, and the drift of applied agents and manure, pollinators are most probably exposed to insecticides but also bacteria from organic fertilizers at the same time.

Hemocyte-mediated phagocytosis differs between honey bee (Apis mellifera) worker castes.

Honey bees as other insects rely on the innate immune system for protection against diseases. The innate immune system includes the circulating hemocytes (immune cells) that clear pathogens from hemolymph (blood) by phagocytosis, nodulation or encapsulation. Honey bee hemocyte numbers have been linked to hemolymph levels of vitellogenin.

The hive bee to forager transition in honeybee colonies: the double repressor hypothesis.

In summer, the honeybee (Apis mellifera) worker population consists of two temporal castes, a hive bee group performing a multitude of tasks including nursing inside the nest, and a forager group specialized on collecting nectar, pollen, water and propolis. Elucidation of the regulatory mechanisms responsible for the hive bee to forager transition holds a prominent position within present day sociobiology. Here we suggest a new explanation dubbed the "double repressor hypothesis" aimed to account for the substantial amount of empirical data in this field.

The regulatory anatomy of honeybee lifespan.

Honeybee workers (Apis mellifera) may be classified as either short-lived summer bees or long-lived winter bees in temperate zones. The protein status appears to be a major determinant of honeybee lifespan, and the lipoprotein vitellogenin seems to play a crucial role. Here, we give a review of the role of the vitellogenin in honeybee workers, and present a data-driven mathematical model describing the dynamics of this representative protein in the individual bee as a function of its task profile under various regimes.