Ants live and work together in multi-generational colonies that are generally organized in “castes” of queens and males (who reproduce) and worker females (who cannot reproduce, communicating via a chemical communication system that may be more complicated than that of any other kind of animal. In addition to these extraordinary social structures, ants have complex and extremely important relationships with many other species, giving them a central role in ecosystems across the globe. Some ants have partnerships with fungi. Some ants defend plants from herbivores, help plants reproduce by pollinating their flowers and spreading their seeds, and help plants grow by turning over the soil (which keeps it rich and healthy. In fact, many plants depend on ants for their survival. On the other hand, some ants are the primary plant-eaters in their environments, and in many cases ants are major predators of small animals. Although some ant species can be pests themselves, some are beneficial to humans by feeding on harmful crop pests and by serving as subjects for a wide range of scientific studies