Coconut Homes

July 18, 2010
By Damond Benningfield

It sounds like something from an episode of the original “Iron Chef.” Take two halves of a coconut shell, place an octopus inside, then simmer in saltwater.

Octopuses have been observed using coconut shells as tools. Credit: National Oceanic & Atmospheric Administration

Except for the “simmer” part, it’s a recipe that a species of octopus created on its own. It’s the first clear example of an octopus using tools to improve its life.

Marine biologists already knew that octopuses are smart. They use pebbles to wall up the entrances to their dens, and in captivity, they can pry open the tops of their tanks and dip their arms into other tanks.

But when researchers in Australia studied the veined octopus in Indonesia, they found a type of behavior that went far beyond what anyone had seen before.

The scientists found several of the critters picking up coconut shells, carrying them over fairly long distances, then stacking two shells together to create a secure home.

The shells were tossed into the ocean by people. The octopuses dug them out of the mud, then sprayed “jets” of water to clean them. They then wrapped their arms around the shells, with the round part facing the bottom, and “tiptoed” across distances of up to 60 feet or so to another shell. They then climbed inside one of the shells and pulled the other one over the top -- creating a snug little home.

The researchers say that the octopuses probably had used abandoned seashells for homes until people started dropping coconuts around them. When life gives you coconuts, you make octopus-in-coconut shell. Just don’t add heat.