Electric Eels, the Original Puppet Master?

Shocking news: Electric eels exert remote control over prey

Electric eels, those perilous predators of South America, can unleash a potent electrical jolt to wallop their hapless prey. But this zap is not used merely to stun other fish.

A new study shows that the eels use it to exert a form of remote control over their victims, causing fish that may be hiding to twitch, thus exposing their location, or inducing involuntary muscle contraction to incapacitate their prey.

"Apparently, eels invented the Taser long before humans," said biologist Kenneth Catania of Vanderbilt University in Nashville, Tennessee, who conducted the research published on Thursday in the journal Science.

The study reveals precisely what an eel's zap does to its victim. In laboratory experiments, Catania showed how the electrical discharges remotely activate the prey's neurons, or nerve cells, that control the muscles.

Yeah, thats' pretty much what happens when you shock a fish, or almost anything else for that matter. The electricity stimulates the muscle, which causes them to contract. . . a twitch.

While hunting, the eels periodically give off two high-voltage pulses separated by a 2 millisecond pause, causing a massive involuntary twitch in nearby hidden prey, the study found. The eels, highly sensitive to water movements, can detect motion caused by the twitch, learning the other fish's location.

We've known a lot about electric fish for a long time. I did a junior high science fair project using an electric catfish I borrowed from the fish store I worked at. Yeah, these days that would get you in trouble for animal cruelty, but back in the early 60s you could do a lot in the schools, including learn.

The only thing I got out of this is that scientists realized that electric eels used the "shock" response to help them sense their prey. But it has also long been known that the eels use the electrical system, using weak power output, as a sense organ, to sense fish nearby. They share this trait with their whole family of South American Knifefish, and some other unrelated fish, including some African fish, and the Torpedo Ray.

Electric eels typically live in very brown and dirty water, and having another way to identify that fish near them besides sight (and they have small, weak eyes) is a considerable help.

The eels can also put off a massive pulse, which can stun a man or even a horse, and certainly any fish nearby. We had a couple of large eels at the fish store.  Ugly as sin, they just sat laid around and zapped the goldfish we fed them. We handled them with great care. Little ones were kind of cute, though.