Polymorphism is an important aspect in termites and ants. It helps to determine their function and what they are able to do. In both ants and termites, there are not that many differences in what the larger and smaller counterparts perform. Larger insects entities tend to perform guard duty or act as a defense. Smaller insects tend to do the rest of the work. And, obviously, there are differences between termites and ants.
Large termites are simply called soldier termites. They are unable to perform small menial tasks due to their enlarged head and mandibles. However, large ants are able to do much more. Larger ants, known as supermajors, also help the worker ants with transporting large food products, either carrying it themselves or cutting up the prey into smaller pieces. In some species, such as the asian marauder ant, the supermajors are used as a form of transport for the workers to conserve energy.