Electric eels' secret weapon: Curl before shocking prey
Scientists have found that the electric eel, which zaps prey with a powerful electric shock to immobilize it, also has more sophisticated electrocution techniques up its proverbial sleeves.
Younger eels, who have less shocking power, curl their bodies around prey to double the voltage of their shock, "sandwiching it between the two poles of their powerful electric organ," according to a in the journal Current Biology.
This powerful shock incapacitates even very large fish, giving the young predators a chance to release and quickly reposition their unwieldy prey in order to swallow it.
"In my mind, it鈥檚 sort of a testament to how even an animal that鈥檚 been studied for centuries may be that we were unaware of [until] we look closely," said Vanderbilt University biology professor Kenneth C. Catania, who led the study, to the Los Angeles Times.
Eels' serpentine bodies contain electric organs with thousands of specialized cells that , explains National Geographic. An eel zaps its prey with a Taser-like, 600 volt shock聽鈥� five times the power of a US wall socket聽鈥� which causes fish muscles to contract.
Prey become temporarily immobilized, giving the eel time to scoop it up and swallow it quickly, before the prey seize "their last, fleeting opportunity to escape as they are briefly released and repositioned," the scientists say.
But younger eels have much less power, and their Amazonian habitat is home to the world鈥檚 most diverse mix of fish, which have different sizes, shapes, and protective features, including spines.
So scientists wanted to know, "What happens when an eel struggles with large prey that may not be easily subdued or swallowed? Or when juvenile eels attack?"
To find out, they stuffed goldfish with electrodes designed to measure shock voltage, and then they fed the goldfish to eels in an aquarium.
They observed young eels curl their bodies like horseshoe magnets, bringing their positive electrical pole (head) closer to their negative electric pole (tail), to amplify their electric strength.
With a doubled shock value, the eels hit their prey with numerous shocks, paralyzing the fish and ensuring a meal.
For Catania, this raises the question of how, with so much electricity flowing through their bodies, do eels avoid shocking themselves?
"How they protect their nervous system and their own brain and their own muscles from being activated 鈥� as far as I know, it鈥檚 pretty much an open question," Catania told the Times.
