ABSTRACT
Cognition The capacity for brain function is commonly assumed to be related to brain size, complexity, and sophistication. Hence, fishes, because of their relatively small (except in the case of sharks) and simple brains, have not been regarded as possessing much capacity for memory, learning, or other cognitive functions. But many fish live in complex social systems that require a cognitive capacity much greater than previously assumed (Laland et al., 2003). While there is much compelling evidence that fishes “teach” or consciously pass on information or knowledge to others, they have been shown to learn by observing and mimicking the actions of other, more experienced (and hence knowledgeable) individuals. Fish learn to recognize others as individuals, not only members of their own species (Binoy and Thomas, 2006), but also members of other species (Stummer et al., 2004). They learn from others becoming more efficient at finding mates and food or avoiding predators. They can spatially encode, and remember, complex environments, allowing them to navigate obstacles and return to precise locations despite the absence of immediate sensory inputs (Burt de Perera, 2004).
