Caste determination is a sequential process:: effect of larval age at grafting on ovariole number, hind leg size and cephalic volatiles in the honey bee (Apis mellifera carnica)

Artificial queen rearing with worker larvae grafted at different developmental stages resulted in gradual effects on ovary size (number of ovarioles per ovary), as well as hind leg and wax gland structures in adults. A significant decrease in ovariole number was observed when third instar larvae were grafted. Basitarsus shape was affected when fourth instar larvae were grafted. Queen-worker intermediates developed when early-fifth instar worker larvae were transferred. As newly emerged adults, spectra of cephalic volatiles of queens and workers are still very similar, and do not yet exhibit the caste-specific elements of the mandibular glands. At one day after emergence, most of the dominant compounds in these spectra are represented at higher levels in workers.