Courting electric fish play the dueling banjos of love

Electric fish, Brienomyrus brachyistius, produce tiny electric signals from an organ in their tails that can be used to communicate and convey social status. They can also be used attract a mate, as reported in a study by Wong and Hopkins in the Journal of Experimental Biology. (The ghetto picture to the right -- the only one I could find that I am certain is of the right fish -- is from Schluger and Hopkins (1987), actually an interesting paper in and of itself. It shows that the fish follow electric field lines.)

In the study, the researchers recording from pairs of mating electric fish. (This is in and of itself an achievement because electric fish are apparently about as willing as pandas to mate in captivity.) During the pre-mating displays, the researchers recorded the electric signals between the two animals and discovered that they form an elaborate dance of electric "rasps" and "bursts" during the courtship.

Graphed by burst duration, the courtship displays look like below. On the graph, the males are green and the females are red.

The other interesting part was that they induced mating by lowering the conductivity of the water in which the animals by adding distilled water. They argue that this simulates rain, the natural breeding trigger of the animal.

Cool.

Their summary:

"Our study provides strong evidence that the 'rasp' [a certain electric signal] is a male advertisement call during courtship in this species," said Wong, noting that the males also serenade females with lower frequency "creaks."

My summary:

"It's electric! Boogie woogie woogie."