The received wisdom is that diet quality drives this queen-worker dichotomy, even though diet quantity differs significantly between queen and worker diet. Diet quantity likely determines honey bee caste; yet it has never been explicated tested. In this paper, we tested the hypothesis of diet quantity induced caste determination by; first, determine the ubiquity of quantity induced caste systems among highly-related taxa; second, determining the relative contributions of diet quantity vs. diet quality on adult caste in honey bees; and third, determine the influence of diet quantity on important cellular and physiological pathways known during caste determination. I found that: 1) diet quantity determines caste in honey bees and other eusocial hymenoptera, and 2) honey bees do not have a critical weight. This research likely will move forward the field of honey bee caste determination, which is a model for high-order sociality and phenotypic plasticity.