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Alessandro Cresci
Alessandro Cresci

Baby Eels Migrate by Following Magnetic Fields

Alessandro Cresci
Alessandro Cresci

Baby eels have joined the ever-growing club of animals that live their lives along magnetic lines. Researchers described these findings in the journal Scientific Advances.

Our planet and its inhabitants are shaped and impelled by invisible forces. Studies have found that foxes hunt and deer flee along north-south lines. Pigs and wild boars orient their nests to face the same way. Lobsters, butterflies, and whales all follow their internal compasses along magnetic lines. Adult European eels, too. But we weren’t really sure about their babies.

Grown-up European eels lay their many eggs in the Sargasso Sea. The eggs hatch into helpless larvae, which bob along in Atlantic currents. As the currents approach the continent, the babies transform again, this time into translucent miniature versions of their parents. These glass eels make their way into the coasts. From there, they swim inland to freshwater and bum around Europe and North Africa for five to 20 years. Finally, as adults, they head back to the sea to start the whole cycle all over again. It's one of the longest migrations in the animal kingdom, the researchers say.

Adult European eel traveling over icy ground on its migration route
Adult European eels are tough and can migrate short distances over land.
Caroline Durif

It’s an impressive feat for the little noodles, and scientists wondered how they pull it off. To find out, researchers scooped up a group of newly arrived baby eels on the coast of Norway. They put the eels in a large chamber inside a fjord and let them swim there for a full tidal phase, watching how the eels positioned their bodies and how they swam.

Next, they brought the eels into the lab and repeated the tide-long observation process.

Unsurprisingly, the little tykes knew exactly what they were doing. They consistently turned their bodies to run parallel with magnetic lines, but the direction of those lines varied depending on the phase of the tides. When the tide went out to sea, the majority of eels swam southward, whether in the fjord or in the lab.

These findings are as fascinating as they are vital, as, for all its ingenuity, the European eel is critically endangered. Understanding this animal’s extraordinary life cycle could help conservationists find ways to protect it better in the future.

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Animals
This Is the Age When Puppies Reach 'Peak Cuteness'
iStock
iStock

All puppies are cute, but at some point in a young dog's life, it goes from "It's so cute I could squeeze it to death" to merely regular cute. But when? According to one recent study in the journal Anthrozoös, peak cuteness hits between 6 and 8 weeks old for many dogs, The Washington Post reports.

Finding out when puppies reach their peak attractiveness to humans may give us insights into how domestic dogs evolved. Researchers from the University of Florida asked 51 students at the school to look at 39 black-and-white images of dogs, who belonged to three different breeds and whose ages ranged from birth to 8 months. The viewers then rated them on a sliding scale of squishability.

The results will sound familiar to dog lovers. Puppies aren't entirely adorable immediately after they're born—they can look a little rat-like—and the participants rated them accordingly. As dogs get older, as much as we might love them, their squee-worthy cuteness declines, as the attractiveness scores reflected. The sweet spot, it turns out, is right around when puppies are being weaned, or between 6 and 8 weeks old.

The participants tended to rate dogs as most attractive when the pups were within the first 10 weeks of their lives. According to the results, Cane Corsos were at their cutest around 6.3 weeks old, Jack Russell terriers at 7.7 weeks old, and white shepherds at 8.3 weeks.

The study only used still photos of a few breeds, and it's possible that with a more diverse sample, the time of peak cuteness might vary a bit. Certain puppies might be cuter at an older age, and certain puppies might be cuter when they're even younger. But weaning age happens to coincide with the time when puppies are no longer getting as much support from their mothers, and are thus at a high risk of mortality. By evolving to attract human support at a time when they're most vulnerable, puppies might have boosted their chance at survival until they were old enough to completely take care of themselves.

[h/t The Washington Post]

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Martin Wittfooth
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Art
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

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