This is a scientific American 60 Second Science. I'm Annie Sneed.

In the 1800s, renowned explorer and naturalist Alexander von Humboldt observed a bizarre incident in the Amazon.

He saw electric eels leaping into the air and shocking two horses.

But some who heard the story thought Humboldt was a humbug.

Humboldt was a humbug.

Humboldt had described ills attacking horses, but people couldn't necessarily believe it.

Kenneth Katanya, a professor of biological sciences at Vanderbilt University. But Humboldt was vindicated last year when Kitanya published a study showing that

electric eels indeed jump in the air to jolt potential predators. This maneuver is the most efficient way for an eel to deliver its shock.

When the animal is submerged, electricity gets lost to the water.

By going airborne...

The eel is essentially using that principle of physics to divert more and more

current into the target.

But Katanya still wanted to know more, like exactly how strong as an eel shock to a human.

To figure out the forces behind this electrifying leap, Katanya used a relatively small

eel and a human subject himself.

I approached the eel with my hand in the container, which has a metal script on it.

And the E.O. decided it was concerned about whatever a parent creature might be coming near it. It came out of the

water as I planned up over the metal piece and onto my arm that allowed me to

measure the current flowing through my hand.

After taking various measurements and getting electrocuted 10 times by the eel,

Katani discovered that even a small eel can deliver as much as 40 to 50 milliamps of electrical current.

That's more than enough to activate the pain receptors and withdrawal reflexes of horses, dogs, and humans.

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