The Brown Paper Nautilus is an argonaut, a free-swimming octopus of open ocean habitats. A species that is widely distributed in the Indo-Pacific Ocean, the Brown Paper Nautilus is known to cling to objects floating on the surface of the sea, including other argonauts. Here a female nautilus is seen surfing on a free-floating medusa. Though the relationship is not fully understood yet, the nautilus is believed to use its host as a food source and as a defensive weapon. When the nautilus was photographed, it used the medusa as an active form of protection by turning it towards the camera, which it presumably perceived as a potential predator.