The Veined Octopus

The veined octopus, amphioctopus marginatus, was found in Indonesia in December 2009 using coconut shells as “portable armor”, adding one more species to the list of animals that engage in tool use. Julian Finn, a marine biologist in the Museum Victoria in Australia, came across the discovery by mistake.¹ He had been looking for the mimic octopus, thaumoctopus mimicus, when he stumbled upon behavior he had never seen before. The octopus dug out coconut shells from the ocean floor, cleaned them of sand using jets of water, and gathered them together for future use to protect itself.² The “comical sight” is pictured to the right. This documentation was in fact the first case of tool use in invertebrates. The researchers, Julian Finn and Mark Norman, spent 500 hours diving underwater off the coasts of Northern Sulawesi and Bali in Indonesia, observing 20 octopuses in all.² On many occasions the octopuses traveled up to 65 feet with the shells.¹ While other animals, such as hermit crabs, use discarded shells as homes, Mark Norman claims that “there is a fundamental difference between picking up a nearby object and putting it over your head as protection versus arranging, transporting...and assembling [the shells] as required”.¹

Veined octopuses are on average 15 centimeters long. They are found in the tropical waters of the Western Pacific Ocean, living on the sandy bottom of bays and lagoons.³ They commonly prey on shrimp, crabs, and clams, and they have a variety of predators. Octopuses are cephalopods, as are squid and cuttlefish. Britannica Online Encyclopedia cites that octopuses can vary in size from the smallest species, at 5 centimeters long, to 18 feet in length.³ Each species has a hard beak, with its mouth at the center of its eight arms.³ They have no internal skeleton, allowing them to squeeze through tight places. Octopuses avoid predators by hiding, like the veined octopus, fleeing, expelling ink, or even by using color-changing camouflage. Almost every species of octopus is venemous, although only one is deadly to humans.⁴ Octopuses have also been shown to be much more intelligent than once thought, demonstrating much mimicking ability. One has even been documented to “slip its arms around a jar, unscrew it, and dine on the crab inside”.⁵

Sources:

1) Choi, Charles Q. "Clever octopus builds a mobile home - LiveScience- msnbc.com."MSNBC.com. 14 Dec. 2009. Web. 19 Feb. 2010. .

2) "Scientists discover coconut-carrying octopus - ABC News (Australian Broadcasting Corporation)."ABC.net.au. 15 Dec. 2009. Web. 19 Feb. 2010. .

3) "Octopus (mollusk) -- Britannica Online Encyclopedia." Encyclopedia - Britannica Online Encyclopedia. Web. 19 Feb. 2010. .

4) "Tentacles of venom: new study reveals all octopuses are venomous. : News : The University of Melbourne." Latest News : News : The University of Melbourne. Ed. Bryan Fry. 15 Apr. 2009. Web. 19 Feb. 2010. .

5) Zimmer, Carl. "How smart is the octopus?" Slate Magazine. 23 June 2008. Web. 19 Feb. 2010. .

6) 1^st Image: Steene, Roger. "Museum Victoria: Tool use in Veined Octopus." Museum Victoria. 15 Dec. 2009. Web. 19 Feb. 2010. .

7) 2^nd Image: "COA 2008 Submissions." City of Peoria, Arizona. Web. 19 Feb. 2010. .