While tool use was once seen as a uniquely human behavior, decades of animal observation has proven just how wrong that really was. We've seen primates, crows, and maybe even octopuses show signs of tool use. But outside of mammals, birds, and octopuses, tool use is close to unknown. There were reports of fish tool use, but no hard evidence to back it up.

That changed when diver Scott Gardner snapped this photo, and there are more like it about to be published in a new paper from Macquarie University researchers. Ecologist Culum Brown explains that the fish hit the clam against the rock with unmistakable precision, suggesting this was an activity it had long experience with. That contention is backed up by the presence of the presence of crushed shells around the rock, and Gardner found plenty more shell remains around the nearby rocks.

Read the story and see the photo from IO9.