Electric Eels Use Their High-Voltage Shocks to Locate Prey

Electric eels use special electricity-emitting organs to stun their prey, and a scientist recently discovered they use these same mechanisms to locate their food in the dark. A study published this week in Nature Communications [PDF] illustrates how these nocturnal creatures use energy fields to “electrolocate” their prey as well as paralyze them with a charge of up to 600 volts.

Ken Catania, a neurobiologist at Vanderbilt University, conducted a series of laboratory experiments in which he observed this shocking behavior in action. He presented the eels with anesthetized fish, blocked from the predators' electroreceptors with plastic bags. When Catania forced the fish to twitch with an electrode, the eel emitted its electrical attack. But after that, it was stumped. The eel lunged towards the movement in the water but made no attempt to devour the fish.

Things got even more interesting once Catania introduced an electrically conductive carbon rod to the tank. After releasing its charge, the eel initially moved towards the direction of the fish only to change its mind and dart towards the rod instead, wherever it had been placed. When Catania moved the rod onto a rotating wheel and removed the fish from the tank entirely, the eel was further confused, writhing to suck up the rod that it perceived to be its prey.

This behavior suggests that electric eels are able to simultaneously use their electric charge as a predatory attack and a tracking system. Catania published a separate study in Science last year that showed how an electric eel’s shock can stimulate its prey’s motor neurons and cause involuntary muscle spasms. After a couple of electric volleys, the helpless fish will have revealed its location before the eel goes in for the kill. The eel sucks up the prey within milliseconds of the attack, which we now know it does by using its high-voltage charge to pinpoint its exact location.

These recent findings place electric eels in the same league as bats, sharks, and other creatures who use a type of “sixth sense” to locate their prey. Sharks and rays can sense the electric fields emitted by other creatures, while bats and some whales use sonar to detect reflected sound. But eels are the only creatures whose locating sense doubles as a weapon, making them even more awesome (or terrifying) than we previously realized. 

[h/t: National Geographic]

Martin Wittfooth
The Cat Art Show Is Coming Back to Los Angeles in June
Martin Wittfooth
Martin Wittfooth

After dazzling cat and art lovers alike in 2014 and again in 2016, the Cat Art Show is ready to land in Los Angeles for a third time. The June exhibition, dubbed Cat Art Show 3: The Sequel Returns Again, will feature feline-centric works from such artists as Mark Ryden, Ellen von Unwerth, and Marion Peck.

Like past shows, this one will explore cats through a variety of themes and media. “The enigmatic feline has been a source of artistic inspiration for thousands of years,” the show's creator and curator Susan Michals said in a press release. “One moment they can be a best friend, the next, an antagonist. They are the perfect subject matter, and works of art, all by themselves.”

While some artists have chosen straightforward interpretations of the starring subject, others are using cats as a springboard into topics like gender, politics, and social media. The sculpture, paintings, and photographs on display will be available to purchase, with prices ranging from $300 to $150,000.

Over 9000 visitors are expected to stop into the Think Tank Gallery in Los Angeles during the show's run from June 14 to June 24. Tickets to the show normally cost $5, with a portion of the proceeds benefiting a cat charity, and admission will be free for everyone on Wednesday, June 20. Check out a few of the works below.

Man in Garfield mask holding cat.
Tiffany Sage

Painting of kitten.
Brandi Milne

Art work of cat in tree.
Kathy Taselitz

Painting of white cat.
Rose Freymuth-Frazier

A cat with no eyes.
Rich Hardcastle

Painting of a cat on a stool.
Vanessa Stockard

Sculpture of pink cat.
Scott Hove

Painting of cat.
Yael Hoenig
Tony Karumba, AFP/Getty Images
How a Pregnant Rhino Named Victoria Could Save an Entire Subspecies
Sudan, the last male member of the northern white rhino subspecies, while being shipped to Kenya in 2009
Sudan, the last male member of the northern white rhino subspecies, while being shipped to Kenya in 2009
Tony Karumba, AFP/Getty Images

The last male northern white rhino died at a conservancy in Kenya earlier this year, prompting fears that the subspecies was finally done for after decades of heavy poaching. Scientists say there's still hope, though, and they're banking on a pregnant rhino named Victoria at the San Diego Zoo, according to the Associated Press.

Victoria is actually a southern white rhino, but the two subspecies are related. Only two northern white rhinos survive, but neither of the females in Kenya are able to reproduce. Victoria was successfully impregnated through artificial insemination, and if she successfully carries her calf to term in 16 to 18 months, scientists say she might be able to serve as a surrogate mother and propagate the northern white rhino species.

But how would that work if no male northern rhinos survive? As the AP explains, scientists are working to recreate northern white rhino embryos using genetic technology. The San Diego Zoo Institute for Conservation Research has the frozen cell lines of 12 different northern white rhinos, which can be transformed into stem cells—and ultimately, sperm and eggs. The sperm of the last northern white male rhino, Sudan, was also saved before he died.

Scientists have been monitoring six female southern white rhinos at the San Diego Zoo to see if any emerge as likely candidates for surrogacy. However, it's not easy to artificially inseminate a rhino, and there have been few successful births in the past. There's still a fighting chance, though, and scientists ultimately hope they'll be able to build up a herd of five to 15 northern white rhinos over the next few decades.

[h/t Time Magazine]


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