Brood temperature
Measurement of brood-temperature in honeybee colonies
Honey bees show an amazing abilitity for a fine-tuned thermoregulation, leading to mean brood-nest temperatures of 34.5°C ± 1.5°C. Heat produced by activation of the thoracic muscles is transferred to the brood cells, if temperatures become too low. Accordingly, if hive temperatures are too high, worker bees start fanning or even carry in water for evaporative cooling.
Although brood-nest temperatures are confined to a narrow range, differences in the mean temperatures during pupal development have significant effects on the behavior of the adult bees. Brood temperatures influence the time for development, the age at onset of foraging and the lifespans of the bees.
Brood-nest temperature is a collective property which affects the global structure of division of labor in the colony. We expect self-organized processes with tight feedback loops between the number of workers in the brood area and the developmental temperatures.
In order to investigate temporal and spatial temperature distributions in a brood-comb, we developed a highly precise device (the "Porcupine") enabling us to measure the temperature in the very vicinity of the developing brood.