Honey bees are larger and live longer after developing at low temperature

Area of Science:

• Entomology
• Animal Physiology
• Apiculture

Background:

• Honey bees (Apis mellifera) are temperature specialists.
• Larval development is sensitive to nest temperature fluctuations.
• Suboptimal temperatures can negatively impact honey bee development and behavior.

Purpose of the Study:

• To investigate the effects of rearing temperature on honey bee (Apis mellifera) worker and drone larvae.
• To compare body mass, emergence, and longevity of bees reared at different temperatures.
• To analyze the body part proportions of drones reared under varying thermal conditions.

Main Methods:

• Worker and drone larvae were reared at cold (32°C) and warm (35°C) temperatures during the capped brood stage.
• Body mass at emergence was measured for both castes.
• Longevity was assessed for emerged workers (in incubators) and drones (in colonies).
• Drone body mass and body part ratios (head, thorax, abdomen) were compared.

Main Results:

• Bees reared at 32°C were heavier at emergence compared to those reared at 35°C.
• Contrary to expectations, bees reared at 32°C exhibited longer adult survival.
• Drones reared at 32°C had proportionally larger abdomens than those reared at 35°C.

Conclusions:

• Cooler brood rearing temperatures (32°C) result in heavier honey bees (Apis mellifera) with increased longevity.
• The findings suggest that previously assumed optimal temperatures may not be ideal for honey bee development and survival.
• Environmental temperature significantly influences honey bee physiology and fitness.