Electroreception in Deep Sea Habitats

Electroreception in Aquatic Animals

• Electroreception is the ability to perceive and act upon electrical stimuli, found only in aquatic or amphibious species because water is an efficient conductor of electricity.
• This ability helps fish navigate and survive in deep sea habitats where humans would struggle to see and hear.

Types of Electroreception

• Passive electroreception: receiving and decoding electric signals generated by other animals to sense their location.
• Active electroreception: possessing bodily organs that generate special electric signals to locate objects, communicate, and detect prey or predators.

Active Electroreception

• Active electroreceptors can differentiate between resistances to identify prey, predators, or neutral objects.
• The range of active electroreception is about one body length, allowing the host to react accordingly.
• One example of active electroreception is the Jamming Avoidance Response mechanism, where weakly electric fish shift their frequency to avoid jamming their electroreception faculties.

Electroreception in Defense

• Electroreception can help animals defend against predators, such as young ray embryos that stop moving when they detect a predator's electric signal.
• The embryo only reacts to signals characteristic of predators, allowing it to conserve energy.

Sharks and Electroreception

• Sharks use electroreception to hunt with precision, detecting electric signals from their prey to ensure a precise strike.
• Sharks have a strong sense of smell, which they use to initially locate their prey, and then rely on electroreception to finalize their attack.
• Humans are poorly equipped to defend against shark attacks, which often occur by accident due to the shark's inability to detect the taste of human flesh through electroreception.

Human Safety and Electroreception

• Scientists are exploring ways to create artificial electroreceptors to disorient and repel sharks from swimming beaches.
• Repeat shark attacks are likely to occur once a human is bleeding, as the electric field is heightened by salt in the blood, creating a feeding frenzy.

Unknowns of Electroreception

• The exact neurological processes that encode and decode electroreception are unclear.
• Researchers are exploring the role of electroreception in navigation, including the possibility that salt water and magnetic fields from the Earth's core interact to form electrical currents used for migratory purposes.