Protists are a diverse group of organisms. All protists are eukaryotic. Many are unicellular, but they may be multicellular, multinucleate, or exhibit a colonial organization. Although most are microscopic, some are much larger, reaching lengths of nearly 200 feet (60 meters). In early, traditional taxonomic schemes, they were united on the basis of being neither plant nor animal nor fungus. Current evidence suggests that protists exhibit characteristics of the plant, animal, and fungi kingdoms.