hin a colony, the caste system is dominated by the queen that is the only reproductive female in the colony. Subordinate to the queen are the workers (daughters) and drones (sons). Like the queen, drones solely serve reproductive roles. The workers are responsible for the rest of the labor. Workers specialize in the performance of different tasks. Workers are responsible for foraging for food, providing shelter, defending the colony, and caring for the colony's brood, which consist of the queen's offspring. Communication Oriental hornets communicate through sound vibrations. The three main types of vibrations used to communicate are taps to the queen, awakening taps, and larval hunger signals. When workers tap while facing the queen, three effects are noted: the queen starts to search the combs for vacant cells in which to lay her eggs in, the workers go back to performing their typical duties, and hunger signals by larvae cease immed iately and are not resumed for at least 30 minutes. The main purpose of these taps seem to be to encourage the queen to lay more eggs. Awakening taps by workers cause a general intensification of activities in the colony. The effects are minimal during the day. At night, however, the vibrations wake the whole colony, which causes the larvae commence their hunger signals and the workers to go forage for food to feed the larvae. Larval hunger signals produce no detectable changes in larval activity during the daytime. The workers, however, pay more attention and give more food to the cells that are in the vicinity of where the vibrations originated. At night, the larvae emulate each other's hunger signals and awake the whole nest. Kin selection and altruism V. orientalis hornets live in colonies in which the workers are all daughters of the queen, so the workers are all sisters. Social wasps are haplodiploid, which means that males are all haploid and develop from unfertilized egg s, while females are diploid and develop from eggs fertilized by drones. Queens commonly mate with only one drone. Each drone has only one set of chromosomes to pass on to its offspring. Thus, sister workers that share pate