With ants the size of people, you can imagine how large the spiders must be. Many of them build nests, webs and traps, and live as solitary hunters. In some cases, however, spiders band together and form a colony.
When this happens, one spider assumes the role of queen, gaining magical control over the others. The hive becomes a single, living thing. New spiders that hatch evolve to fulfill specialized roles to best serve the hive.