Nurse bee behavior manipulates worker honey bee reproductive development

The evolution of nonreproductive castes is a fundamental question in evolution biology. Honey bee workers , nonreproductive females, don’t reproduce when the queen present in the nest, but have ovaries. The number of ovarioles (ovarian filaments) influences the worker social behavior as well as propensity to become an egg-layer in the absence of the queen.  Previous studies have shown that the number of ovarioles is resulted from nurse bee feeding behavior and larval developmental programming.  In this study, we tested how nurse bees affect ovariole number and body mass in workers, and how worker larvae respond to food delivery during different larval life stages. We found that nurses controlled larvae growth and ovariole number by temporarily manipulating food delivery. Body mass of worker larvae was more sensitive to nutrition during the first to the fourth instar, whereas ovariole number of workers was more sensitive during the fifth instar. We conclude that nurse feeding behavior during the fifth instar is critical for modulating ovariole number in workers.