Kenneth Catania started studying electric eels a few years ago, and soon became obsessed. In quick order, he showed that they paralyze their prey with intense high-voltage shocks, which stimulate the neurons that feed into muscles, forcing the victim's body to involuntarily stiffen. He discovered that they can generate subtler shocks to make their prey twitch, and so give away their position. And, as I covered just last week, he found that they use electric fields to sense the position of their helpless targets and guide their final strikes.
Last year, he started noticing something odd. Although electric eels typically swallow their stunned victims with a quick strike, they sometimes curl their bodies around their prey, pinioning them between head and tail. "I wrote a little note to myself on a Post-It, saying: Is there an effect?" he says. As it happens: yes.
What's the most musical part of a fish? The scales!
How do you make a goldfish age? Take away the "g"!