The pelvic fin is a type of paired fin found in many species of fish, located on the underside of the body. These fins play a crucial role in stabilizing the fish while swimming and can assist in steering and maneuvering. In some species, pelvic fins are also involved in reproduction and can help in holding onto mates during mating rituals. In addition to fish, pelvic fins are present in some aquatic animals, such as amphibians and marine mammals. The structure and function of pelvic fins can vary significantly among different species, reflecting their adaptations to specific environments and lifestyles.