We use tools everyday: cars, hairbrushes, plastic boxes. Tools are all around us. But other animals use tools too! Tool use has been described in diverse animals: primates, birds, fish, insects, crustaceans, cephalopods, etc.
There have been controversies about the definition of tool use. You can read this paper of Culum Brown in you want more information. We consider that tool use is the use of an external object to achieve a goal when the animal lacks the physical or behavioural capacity to achieve this on its own. The capuchin monkey can't crack the nut with its hands and uses a rock as an anvil to do it.
Tool use offers great advantages, accessing food that would be otherwise inaccessible, protecting itself better from predators and so on. Given these advantages, why not all animals are using tools? We are investigating this question using our glass of evolutionary biologists, see the research project.
We focus on tool use in fishes. Yes, fishes can use tools! Not much is known about tool use in fishes maybe because humans have difficulties staying underwater for a long time and following fishes, and they have generally considered fishes as stupid. The literature about this subject is a list of anecdotes from opportunistic observations often made on a single individual. Only tool use in archerfishes have been properly studied. Examples of tool use in fishes can be divided into two types: the use of water as a tool and anvil use.
Our research project focus on anvil use. We hope it will help to understand the evolution of tool use, get a more complete picture of tool use (that is currently focused on primates and birds), and make people realise that fish are intelligent.