Event:

Weakly electric fish generate electric organ discharges (EODs) from an electric organ in the tail. They sense their own EODs with sensory cells called electroreceptors to detect objects around them, and sense the EODs of other fish for communication. But EODs are metabolically expensive to generate, and can be detected by electroreceptive predators like electric eels. Some species of electric fish save energy (~30-60% of estimated costs of EOD) by ramping up their EOD amplitude only when they are active at night, and decreasing EOD amplitude when they are resting during the day. This occurs by hormone-mediated trafficking of voltage-gated sodium channels in the electric organ membrane. Also, different species of electric fish generate EODs with different frequency ranges using different types of potassium channels in the electric organ. Thus, the frequency range and amplitude of an electric communication signal is shaped by the expression and regulation of different ion channels.