These small nematodes are parasites of rodents. They do not constitute much of a threat to natural rodent populations, but are important from a scientific standpoint because they have been used extensively as a model host-parasite relationship to study behavior, immunology, physiology, pathology and ecology. They are a good example of a direct life cycle nematode, typical of many that infect domestic animals. The name arises from the coiled body shape of the adult, which also inspired another name that these parasites often go by, Nematospiroides.