WIKIMEDIA, OPENCAGEThe electric eels that inhabit the Amazon River basin have long fascinated scientists and explorers. At the dawn of the 19th century, Prussian naturalist and explorer Alexander von Humboldt described Venezuelan fisherman capturing electric eels (Electrophorus electricus) by “fishing with horses.” The natives would lead horses into shallow pools where the fish would reportedly jump from the water, shocking the horses until the eels fell exhausted back into the water. The fishermen would then scoop up their quarry. The veracity of the account was long debated, but now a researcher at Vanderbilt University has verified the behavior in electric eels, which are actually a type of knifefish, publishing his results in PNAS this week (June 6).
The defensive behavior, neuroscientist Kenneth Catania wrote in his paper, “consists of an approach and leap out of the water during which the eel presses its chin against a threatening conductor while discharging high-voltage volleys.” Catania, who has made a career out of studying electric eel behavior, noticed the fish would lunge out of the water in their holding tanks and deliver electrical shocks when he would try to transfer them with metal-rimmed nets. “Sometimes up to half of their body rises out of the water,” he told New Scientist. “They don’t seem like dexterous animals but they are good at it.”
So Catania set up experiments where he would stick a fake alligator head, lined with LED lights, into tanks holding the eels to ...
