Originally discovered in 1964, Amphioctopus marginatus, commonly known as Veined Octopus or Coconut Octopus, dwells in the tropical waters of the western Pacific Ocean. The Coconut Octopus is named so for a very peculiar behavior: it carries coconut shells and clam shells across the ocean floor and uses them to build fortresses. It is the only invertebrate known to use tools, and one of only two octopuses known to exhibit bipedal behavior by "walking" on two of its legs.