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Snakes: Ian Macdonald / Art: Rebecca O'Connell
Snakes: Ian Macdonald / Art: Rebecca O'Connell

This Snake’s Venomous Powers Morph as It Grows Up

Snakes: Ian Macdonald / Art: Rebecca O'Connell
Snakes: Ian Macdonald / Art: Rebecca O'Connell

Our relationship to food changes as we age. Our metabolisms slow. We start carrying antacids when going out to dinner. Sometimes we’ll even intentionally eat vegetables. But our transformation has nothing on the brown snake, whose venom gradually morphs to accommodate its new eating habits. Researchers described the snake’s enviable aging process in the journal Comparative Biochemistry and Physiology, Part C: Toxicology & Pharmacology.

Australian brown snakes (genus Pseudonaja) pack some of the most deadly venom in the world. As the authors of the new paper note, brown snakes are also “responsible for the majority of medically important human envenomations in Australia.” And that's saying something.

To better understand how that venom works, researchers collected samples from adult and juvenile snakes from nine known Pseudonaja species. Then they tested each venom’s effect on blood and other substances.

Eight out of the nine species showed a distinct change in venom action between the snake’s youth and adulthood. Brown snake venom is known for its anticoagulant, or blood clot–preventing, properties, which can lead to deadly strokes in small animals and internal bleeding in humans. But only the grown-ups’ venom contained anticoagulants. The babies’ toxic spit had its own power: attacking the nervous system, causing paralysis.


Juvenile (L) and adult (R) brown snakes.
Snakes: Stewart Macdonald / Art: Rebecca O'Connell

The venom’s transformation over time is not random, lead author Bryan Fry, of the University of Queensland, says, but a brilliant adaptation to the snake’s preferred diet at different stages in its life. Baby brown snakes eat tiny lizards, while adults prefer meatier—but scrappier—mammalian fare like rodents. They need a venom that knocks out their opponents fast.

"Young brown snakes may produce clinical symptoms like that of a death adder, as they seek out and paralyze sleeping lizards,” Fry said in a statement. "Once older, their venom contains toxins that cause devastating interference with blood clotting, causing rodent prey to become immobilized by stroke.”

Within the adult snakes’ venom lay another surprise. Scientists knew that brown snake venom worked by converting one blood protein into another, but other snakes do that, too, and their venom isn’t as fast-acting. Some other, hidden process, was going on, and Fry and his colleagues found it.

"Our team discovered brown snakes are potent in activating Factor VII, another blood-clotting enzyme, which is the missing (dark matter) element of brown snake envenomations,” he said. "The feedback loop created by this enzyme would become a venomous vortex and dramatically accelerate the effects upon the blood."

Reminder: It’s not that brown snakes want to be responsible for medically important human envenomations. Like sharks and bears, they’d much rather be left to go about their business. So the best thing for you, and them, is to leave them alone.

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