The primary characteristic that defines eusocial species is reproductive division of labour. Honey bee (Apis mellifera) colonies typically have a single reproductive queen and thousands of sterile workers. Here, I review the factors affecting worker reproduction and then contrast the brain gene expression of workers considered either reproductively altruistic (sterile) or selfish (fecund) over a series of time points. I confirmed that although, theoretically, the genes that allow workers to reproduce must be expressed in order for them to do so, it is the environmental cues, such as nutrition and pheromones, that ultimately control worker reproductive status. I then identify a new set of candidate ‘genes for reproductive altruism’ by considering the differential gene expression of reproductive vs. sterile worker brains on each day, and over multiple consecutive time-points. It was determined that a large portion of the identified genes had metabolic function
