"I really wasn't expecting to see tool use appear in cephalopods"-squid, cuttlefish, and octopuses-said biological anthropologist Craig Stanford, co-director of the Jane Goodall Research Center in Los Angeles, who wasn't involved in the new study. It's been known for years now that chimpanzees use whole "tool kits," that some dolphins attach sponges to their beaks for fishing, and that crows fish for insects using sticks and leaves, for example.Įven so, the octopus discovery stands apart. Tool use, once thought to be a uniquely human behavior, is seen as a sign of considerable mental sophistication among nonhuman animals. In captivity they've been known to navigate mazes, seem to be able to remember past events, and are cunning escape artists. Octopuses of many species are well known for their intelligence. The octopus's coconut carrying qualifies as tool use, Finn said, because the shells provide only "delayed benefits." Tools, by definition, provide no benefit until they're used for a very specific purpose-showing that the animal is capable of what you might call advance planning. Worn nearly constantly, a hermit crab's adopted shell isn't considered a tool, because it's always useful. So what makes the veined octopus's behavior tool use, versus, say, the hermit crab's use of seashells as armor? "But on endless mud seafloor, where are you fleeing to?" In other words, a coconut-carrying octopus may be slow, but it's always got somewhere to hide. "An octopus without shells can swim away much faster by jet propulsion," he said. To carry the shells, a veined octopus has to stick its arms out and over the edges of the coconut and walk around as if on stilts-making the octopus, while in motion, more vulnerable to predators-study leader Finn explained. "I've always been impressed by what octopuses can do, but this was bizarre," said study co-author Norman, senior curator for mollusks at Museum Victoria. Then they noticed that the octopuses, after using the coconut shells, would arrange them neatly below the centers of their bodies and "walk" around with the shells-awkwardly. The researchers noticed that the animals were frequently using their approximately 6-inch-long (15-centimeter-long) tentacles to carry coconut shells bigger than their roughly 3-inch-wide (8-centimeter-wide) bodies.Īn octopus would dig up the two halves of a coconut shell, then use them as protective shielding when stopping in exposed areas or when resting in sediment. The octopus’s donut-shaped brain wraps around its esophagus so it has to eat tiny bites of food, or else its expanding esophagus would damage its brain.
It ‘skulks’ away to find a safe place to devour its catch, away from predators. The fanning and pulsing of the octopus’s body indicates that it’s taken prey into its arms. But, the octopus grabs something next to the urchin – likely a bivalve or crab. This urchin is not on the menu – it’s too spiny to eat. Walking and mimicry are common for octopus species in sandy habitats.
Febru“The creeping murderer, the octopus … pretending now to be a bit of weed, now a rock … runs lightly on the tips of its arms.” – John Steinbeck, Cannery Row Actually, this coconut octopus is on the hunt for food, and may be carrying prey that it’s already caught.
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