History and Evolution of Electroreception
– Hans Lissmann discovered electroreception in 1950 through observations of Gymnarchus niloticus.
– Stefano Lorenzini discovered ampullae of Lorenzini in sharks in 1678.
– R. W. Murray established the electroreceptive function of ampullae of Lorenzini in 1960.
– Viktor Franz described knollenorgans in elephantfishes in 1921.
– Electroreception is an ancestral trait in vertebrates.
– Electric organs have evolved independently at least eight times in vertebrates.
– Some groups of fish are able to deliver electric shocks.
Electrolocation and Mechanisms of Electroreception
– Ampullae of Lorenzini are jelly-filled canals that detect small differences in electrical potential.
– Electroreceptive animals use electrolocation to locate objects in environments where vision is limited.
– Electrolocation can be passive or active.
– Passive electrolocation relies on sensing bioelectric fields generated by other animals.
– Active electrolocation involves generating weak electric fields and detecting distortions in these fields.
– Passive electroreception is important in ecological niches where vision is limited.
– Active electroreception is used by weakly electric fish.
Electroreception in Specific Species
– Sharks rely on electrolocation using their ampullae of Lorenzini.
– Sharks are the most electrically sensitive animals known.
– Neotropical knifefishes and African elephantfishes are weakly electric and electroreceptive.
– Gymnotiformes, including electric eels, can generate high voltage electric shocks.
– Platypus is a monotreme mammal that has secondarily acquired electroreception.
– Dolphins, such as the Guiana dolphin, possess electroreceptive abilities.
– Bees, particularly bumblebees, can detect and learn floral electric fields.
Electrocommunication
– Electric eels create powerful electric fields to stun prey.
– Weakly electric fish can communicate by modulating their electrical waveform.
– Electric catfish use electric discharges to ward off other species.
– Glass knifefishes shift their discharge frequencies in response to each other.
– Some fish prey on electrolocating fish by eavesdropping on their discharges.
Applications and Implications of Electroreception
– Electroreception in fish, amphibians, and monotremes is crucial for survival and hunting.
– Electroreception in dolphins helps them detect prey and navigate in their environment.
– Bees use electroreception to locate and identify flowers for pollination.
– Understanding electroreception in bees helps us comprehend their ecological interactions.
– Further research and reading can be done to explore the intricacies of electroreception. Source: https://en.wikipedia.org/wiki/Electrogenic
Electroreception and electrogenesis are the closely related biological abilities to perceive electrical stimuli and to generate electric fields. Both are used to locate prey; stronger electric discharges are used in a few groups of fishes (most famously the electric eel, which is not actually an eel but a knifefish) to stun prey. The capabilities are found almost exclusively in aquatic or amphibious animals, since water is a much better conductor of electricity than air. In passive electrolocation, objects such as prey are detected by sensing the electric fields they create. In active electrolocation, fish generate a weak electric field and sense the different distortions of that field created by objects that conduct or resist electricity. Active electrolocation is practised by two groups of weakly electric fish, the Gymnotiformes (knifefishes) and the Mormyridae (elephantfishes), and by Gymnarchus niloticus, the African knifefish. An electric fish generates an electric field using an electric organ, modified from muscles in its tail. The field is called weak if it is only enough to detect prey, and strong if it is powerful enough to stun or kill. The field may be in brief pulses, as in the elephantfishes, or a continuous wave, as in the knifefishes. Some strongly electric fish, such as the electric eel, locate prey by generating a weak electric field, and then discharge their electric organs strongly to stun the prey; other strongly electric fish, such as the electric ray, electrolocate passively. The stargazers are unique in being strongly electric but not using electrolocation.
The electroreceptive ampullae of Lorenzini evolved early in the history of the vertebrates; they are found in both cartilaginous fishes such as sharks, and in bony fishes such as coelacanths and sturgeons, and must therefore be ancient. Most bony fishes have secondarily lost their ampullae of Lorenzini, but other non-homologous electroreceptors have repeatedly evolved, including in two groups of mammals, the monotremes (platypus and echidnas) and the cetaceans (Guiana dolphin).
