Have you seen fish using tools?

This post was written by Barrett Wolfe. It first appeared on the Redmap website and is reproduced here with minor changes, so that Australasian Fishes Project members will be made aware of the request.

Some fish use rocks and corals as anvils to crack open hard-shelled prey. The fish images, above and below, were taken by Joseph Garcia. They show a Graphic Tuskfish, Choerodon graphicus, striking a cowrie shell on a rock. Two scientists at Macquarie University, Juliette Tariel-Adam (photo above) and Professor Culum Brown are running a citizen science program on this behaviour and need your help.

Divers have reported that some fish can grab a prey item (typically an urchin or clam) and bash it rapidly and repeatedly onto a hard surface until it breaks. This is a case of tool use: The fish uses an external "object" to extend its physical capabilities and limit the oral damage caused by broken shells or spines.

Have you seen this behaviour during your snorkels, dives or at an aquarium? Please fill the participation form available at https://fishtooluse.com or send an email to juliette.tarieladam@gmail.com. Any information is helpful, so don't hesitate.

Otherwise, open your eyes! You might see a fish using a rock as an anvil very soon. Try to identify and remember the species/genus/family of the fish when you see it.

Your participation would help identify all species of fish that use anvils in order to (1) find out if this behaviour evolved one or more times in the evolutionary history of fish, and (2) test hypotheses about the evolution of tool use, such as whether tool use only evolves in species with large brains. Check the project website if you want to know more https://fishtooluse.com