Finding Nemo character Dory is not representative of her kind, according to a new study that proves fish are more intelligent than previously thought.
The popular Disney film depicts Dory as a typical fish, forgetting her surroundings and circumstances almost instantly due to a ‘three-second memory’.
That image could be a thing of the past thanks to scientists who have uncovered the first evidence that fish are able to process multiple objects at once.
Researchers say this proves fish are cleverer than their reputation and could pave the way for medical advances, assisting stroke patients or those with attention deficit disorders.
The University of Bath and Queen Mary University of London study is the first to identify parallel visual search, the ability to pick out one item in many, in zebra fish.
Until this point, parallel visual search had only been identified in primates, rats and pigeons and scientists assumed fish did not possess it.
It was believed that, without the frontal part of the brain in the neocortex, fish would have to examine each object individually rather than a whole scene together.
In the study, 11 adult zebra fish were presented with different coloured circles on a computer monitor over a six-day period to test their visual processing abilities.
The research could pave the way for medical advances
The zebra fish were taught to associate food with a red disc and − to the delight of researchers − managed to quickly pick it out from a pile of other distracting discs.
Michael Proulx, of the University of Bath’s Department of Psychology, said: “Although vision seems simple and quick, it involves a lot of computational power to figure out where things are in a crowded environment. It is incredible to discover that the zebra fish brain, with its small size and simple structure, can seemingly find a target visually without getting slower. No matter how many items we added to the scene to distract the fish, they had no problem responding at the same speed every time. The zebra fish is an excellent model organism to study behavioural genetics and neurobiology thanks to its smaller brain and transparent skin.
“Now that we have discovered their mental sophistication, there is a great opportunity to discover the neural code and genetics of how humans pay attention, and apply those findings to treatments for those with ADHD or strokes.”
Other studies have found that fish are able to pick the larger of two groups of objects, count up to at least four and have comparatively lengthy memories.
Co-author Matthew Parker, from Queen Mary University of London, added: “Fish don’t deserve their reputation as the stupid branch of the animal family tree, the more research we do the more we find out that they are capable of quite complex learning and problem solving. This could be because being part of a shoal requires complicated interactions with their environments and quick processing of large amounts of information.”