Wetland ecosystems contain species that have evolved in a wet environment. Adaptations to an aquatic life include: fins on fish, webbed feet on frogs and ducks, waterproof feathers/fur on darters and platypus, a second clear eyelid that can act like goggles when swimming underwater on multiple species, and camouflage coloring of fur/skin.
Wetlands occur in the polar desert regions of the Arctic and Antarctic. However, given the extremes of the Antarctic climate, the wetlands occurring in the desert oases along the Antarctic coast are distinct from wetlands in the Arctic desert regions because of the absence of vegetation and macrofauna.