New research on Blind cave fish has found that they can put even dogs to shame in the intelligence stakes.
Dr Theresa Burt de Perera, an ethologist at Keble College Oxford, studied the behaviour of the Mexican Blind cave fish, Astyanax fasciatus, which in the absence of working eyes, relies on minute changes in pressure to detect the presence of objects in the water.
By using the sensitive lateral line system to detect changes in pressure, they're able to swim around without banging their heads against the glass, rocks or other fish. Blind cave fish swim much more quickly when they are faced with landmarks, like rocks, which they haven't encountered before, presumably to enhance lateral line stimulation.
However, besides the well-known ability for the cave fish to swim around obstacles in its path without bumping in to them, Burt de Perera also found that the fish built a complex spatial map of their surroundings only a few hours after being added to the tank.
Burt de Perera added four obstacles to the tank and found that the fish learnt the square configuration of it. However, when the landmarks were removed and replaced with another one, the fish showed a change in their behaviour. Burt de Perera says that the change in behaviour shows that the fish had produced a mental map of the obstacles and were comparing it to what they were sensing with their lateral lines.
She told The Telegraph: "The public perception of them is that they are pea-brained numbskulls that can't remember things for more than a few seconds. We're now finding that they are very capable of learning and remembering, and possess a range of cognitive skills that would surprise many people."
PFK's Editor, Karen Youngs, was also quoted by The Telegraph. Karen told the paper: "They are totally misunderstood. We know from our readers that fish can recognise their owners, and some will go into a sulk if someone else tries to feed them. We also know that fish such as oscars do enjoy having a table-tennis ball to bash about."
For more information see: Burt de Perera, T. (2004) A study of spatial parameters encoded in the spatial map of the blind Mexican cave fish (Astyanax fasciatus). Animal Behaviour. In Press.