Zap! Biologist measures electric eel’s shock on his own arm

Talk about dedication to science! This biologist stuck his arm into an eel tank – 10 times – to get an accurate measure of an eel’s shock. He said it felt “like touching a horse fence.”

A Vanderbilt biologist reached into electric eel tank in order to come up with an equation to measure shocks.

What does the shock of an electric eel feel like? Vanderbilt University researcher Ken Catania knows intimately, because he stuck his arm into a tank with a small eel – 10 times.

It was the only way, Catania said, to get accurate measurements of the circuit created by animal, arm and water. Measuring the shock from those interactions allowed him to solve an equation he can extrapolate to measure the power released by big eels – whose shock, it’s said, feel like getting tasered nine times at once.

A series of photos captures Finless, a juvenile electric eel, jumping out of the water to shock Catania’s arm. Image via Ken Catania/Vanderbilt University.

Catania worked with a 16-inch-long juvenile eel he affectionately named Finless. Catania said in a statement:

Eels are essentially batteries immersed in water, and I wanted to solve the question of how powerful those batteries are. What’s the internal resistance of the battery? What’s the resistance of the water? My past research left out the last variable: my arm.

To close the circuit and get the measurement, he created a device that used copper wire to conduct the electricity from the shock to his arm back to the water, one of the methods documented in his paper, published September 14, 2017 in the journal Current Biology.

Electric eels making leaping attacks: Kenneth Catania has discovered that electric eels make leaping attacks that dramatically increase the strength of the electric shocks they deliver.

Catania studies the neurobiology of predators and prey. Last year, he confirmed a controversial 200-year-old account of eels leaping out of Amazonian waters to shock horses. Documenting the eels’ leaping ability left him wondering about the resistances and current for each component of an attack. Catania said:

[Eels] are so much more sophisticated than we possibly could have imagined. This animal can generate hundreds of volts, but they’ve also evolved to very efficiently deliver that electricity.

Enjoying EarthSky so far? Sign up for our free daily newsletter today!

Donate to EarthSky: Your support means the world to us

Bottom line: A Vanderbilt biologist stuck his arm into an electric eel tank 10 times to measure the shock. Video.

Read more from Vanderbilt University

Eleanor Imster