The nutritional needs of bees are supplied by nectar carbohydrates and by protein and other nutrients in pollen, but little is known of how they achieve nutritional balance from floral sources. Using newly emerged caged worker honeybees (Apis mellifera scutellata), whether bees maintain their intake target when confined to pairs of imbalanced complementary diets varying in protein to carbohydrate (P: C) ratio was investigated. The diets were formulated using three protein sources (casein, royal jelly or Feed-Bee(r), a natural pollen substitute) and sucrose. Honeybees from five colonies...