Electric Fishes

Sexual signals in electric fishes.

Electroreceptive bony fishes of Africa (the Mormyriformes) and South America (the Gymnotiformes) detect and communicate with conspecifics by their continuously discharging electric organs. Laboratory studies of members of each group are beginning to reveal the mechanisms of communicating with and finding mates, offering much scope for future studies of the behavioral ecology of electric fishes.

The Electrophysiology of Electric Organs of Marine Electric Fishes

Studies on the electric organs of Narcine brasiliensis and particularly of the responses of the electroplaques of the accessory organ confirm and amplify data obtained on the electroplaques of Torpedo nobiliana. Only the innervated surface is electrogenically reactive and the uninnervated surface has a low resistance, as in Torpedo electroplaques. However, in the accessory organ of Narcine the ...

Electric fishes: neural systems, behaviour and evolution.

Male-mediated species recognition among African weakly electric fishes

Effective communication among sympatric species is often instrumental for behavioural isolation, where the failure to successfully discriminate between potential mates could lead to less fit hybrid offspring. Discrimination between con- and heterospecifics tends to occur more often in the sex that invests more in offspring production, i.e. females, but males may also mediate reproductive isolat...

Brain evolution triggers increased diversification of electric fishes.

Communication can contribute to the evolution of biodiversity by promoting speciation and reinforcing reproductive isolation between existing species. The evolution of species-specific signals depends on the ability of individuals to detect signal variation, which in turn relies on the capability of the brain to process signal information. Here, we show that evolutionary change in a region of t...