How do electroreceptors help a platypus hunt prey?

The platypus (Ornithorhynchus anatinus) utilizes a sophisticated electromechanical system to hunt for prey, such as larval insects and crustaceans, while submerged in freshwater. Because the platypus essentially shuts down its senses of sight, smell, and hearing while underwater, it relies on electroreceptors located on its bill to navigate and locate food.1

These electroreceptors are derived from modified mucous glands that conduct weak electrical signals from the environment to the bare nerve endings of the trigeminal nerve. As the platypus shovels through streambed debris, it uses these receptors to detect the minute direct current (DC) electric fields naturally generated by the muscles of its hidden prey. This ability allows the platypus to hunt effectively in dark or turbid water, even in the absence of other sensory cues.21