Hymenoptera

             The insects most beneficial to humans are found in the large insect order Hymenoptera. Bees and many of their relatives are pollinators of flowering plants, including fruits and vegetables and thousands of species of small wasps are parasites of other arthropods including pest insects. Without these parasites that limit the growth of insect populations, pests would overtake most crops. The urban pests of the order Hymenoptera are the stinging insects, which feed their young largely on flies and caterpillars. Many of these stinging insects are social and live in colonies with a division of labor and overlapping generations. The colonies of ants and honeybees persist for many years, while stinging wasp's start anew each year.
             Many animals live in groups, but not all animals that live in a group are social. True sociality (eusociality) is defined by three features. The first is that there is a cooperative brood-care, so it is not each one caring for there own offspring. The second is that there is an overlapping of generations so that the group or colony will sustain for a while. Which in turn would allow offspring to assist parents during their life. The third feature is that there is a reproductive division of labor. In the case of insects there is one or a few reproductive "queens" or "kings" and the workers are more or less sterile. Hymenoptera are considered to be Eusocial, which was considered to be extremely rare in not only insects, but also the entire animal kingdom except in Ants, Bees, and Wasps until just recently when this was expanded to a few more groups.
             Natural selection depends on the transmission of "traits" that convey selective advantages to the individuals, and these traits have to be determined genetically, so that they are inheritable. So the question of how workers if they were sterile, could transmit the "helping traits" to the next generation arose.