The species is physically indistinguishable from humans, but internally they are quite different. While they are capable of surviving on land, individuals must periodically enter a body of water to re-hydrate their cells. If they fail to do this, they will dehydrate and die. They are capable of spending prolonged time beneath the ocean without breathing equipment, due to heightened lung capacity and greater oxygen intake. Members of the species are physically stronger than humans, and some members of the species can communicate telepathically with certain sea creatures like whales.