Tool-using fish caught on camera

Science : Tool use was once thought to be the exclusive province of human intelligence, but in recent decades it’s been identified in a wide variety of animals, from monkeys and crows, to elephants and octopiand now, fish. There have been a few reports of fish using tools to crack open mollusks and other hard-shelled prey in the past, but until now, no photographic or video evidence has been available to back them up.Scott Gardner, a professional diver, found a blackspot tuskfish holding a clam in its mouth and hitting it against a rock. The shell broke open, the fish ate the clam and spat out the shell fragments, and swam away. Crushed shells around the rock suggest that this was not a unique occurrence. The report is in the journal Coral Reefs .There is some difference of opinion about what constitutes tool use. Under the strictest definition, animals hitting or dropping shellfish against rocks are classified as proto-tool users because they don’t carry or hold the tool. That definition skews things in favor of primates, says Culum Brown of Macquarie University in Sydney, Australia, to ScienceNow‘s Rebecca Kessler. Brown points out that fish, dolphins, and whales don’t have anything but their mouths to manipulate tools with, and that water creates different physical limitations than air.