Electric Fish Plug In To Communicate (via ScienceDaily)
The fish generate electric fields to navigate, fight and attract mates in murky streams and rivers throughout Central and South America. They do so at night, while trying to avoid predators such as catfish that sense the electric fields.
Generating electricity is costly (ask any homeowner paying for air conditioning during a hot summer), and the fish are using a dimmer switch to save energy by turning their electrical signals up and down, says Harold Zakon, professor of neurobiology….
They found that the dimmer switch comes in the form of sodium channels the fish insert and remove from the membranes of special cells, called electrocytes, within their electric organs. When more sodium channels are in the cell membrane, the electric impulse emitted by the electric organ is greater.
The scientists also show that the process is under the control of hormones. And it is maintained through a day-night circadian rhythm and can change rapidly during social encounters….
