Electric Eel Curls Tail Around Body of Prey to Deliver Greater Electric Charge

Posted on October 29, 2015

Kenneth Catania, the Stevenson Professor of Biological Sciences at Vanderbilt University, at the University of Vanderbilt has been studying the electric eel. The eel's body contains specialized cells called electrocytes that store electricity like small biological batteries. The eel can use these cells when attacking prey or defending itself to emit electrical discharges of at least 600 volts. The researchers found that the eels can deliver a great electric change by wrapping their tails around their prey.

Electric eels use the maneuver to sandwich struggling prey between positive and negative electrical poles. The maneuver brings the positive pole of the eel's electric organ (located in its head) in close to proximity to its negative pole (located in its tail). Catania says that by bringing the two poles close together - with the prey sandwiched in between - the eel increases the amount electric charge it delivers to its victim. Catania studied the impact this increase power and pulse rate had on the eel's victim. He found that it drives the prey muscles so fast and hard that they suffer from profound muscle fatigue.

Catania says in a statement, "The prey animals are completely paralyzed. The effect is comparable to administering a dose of a paralytic agent like curare."

Catania also says, "Historically, electric eels have been viewed as unsophisticated, primitive creatures that have a single play in their playbook: shocking their prey to death. But it turns out that they can manipulate their electric fields in an intricate fashion that gives them a number of remarkable abilities."

The Vanderbilt electric eel expert also says the eels can use short sequences of two or three millisecond, high-voltage pulses to scan for prey in muddy waters. This is useful in an environment like the Amazon which is filled with muddy water and vegetation for small fish to hide. Catania also says the electric eels can its use high-voltage electric discharges as a high-precision radar system to track fast-moving prey.

Catania says, "This dual use of the high-voltage system as both a weapon and a sensory system indicates that the eels' hunting behavior is far more sophisticated than we have thought."

The research paper was published here in the journal Current Biology.



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