of the two fish. The jamming avoidance response comes into play when fish are exposed to a slow beat. If the neighbour's frequency is higher, the fish lowers its frequency, and vice versa. A similar jamming avoidance response was discovered in the distantly-related Gymnarchus niloticus, the African knifefish, by Walter Heiligenberg in 1975, in a further example of convergent evolution between the electric fishes of Africa and South America. Both the neural computational mechanisms and the behavioural responses are nearly identical in the two groups. See also Feature detection (nervous system) References Electroreceptive animals Neuroethology Articles containing video clips Bioelectricity