Sydney Stringham, University of Utah
Sydney Stringham, University of Utah

Scientists Say Fancy Pigeons’ Floofy Feet Are Actually Partial Wings

Sydney Stringham, University of Utah
Sydney Stringham, University of Utah

Is there anything better than a proud and fancy pigeon? (No. The answer is no.) And they’re not just pretty faces; they’re also modern-day scientific stand-ins for their dinosaur ancestors. Scientists interested in the dinosaur-to-bird transition have found that the gene responsible for some pigeons’ feathery feet is better known for creating forelimbs—and in birds, that means wings. The report was published in the journal eLife.

If you’ve never heard of fancy pigeons, well, sit down, because you’re in for a delightful ride. They’re like regular pigeons, except they’re fancy. Okay, there’s more to it than that. People have been breeding pigeons for 500 years, carefully pairing individual birds to create specific body types, feather configurations, and even behavior. The results are surprisingly exotic and often quite beautiful.

But the pigeons you see in the park don’t have feathers on their feet. They’ve got scaly, stereotypically dinosaur-looking legs. So what’s producing the foot floofs (also known as muffs) on their fancier counterparts? Biologist Mike Shapiro and his colleagues decided to find out.

Look at these birds! How are they real?!? Image Credit: Sydney Stringham, University of Utah

They started the old-fashioned way: making pigeon babies. The researchers crossed a floofy Pomeranian pouters with scaly-footed-Scandaroons, and then they crossed their kids to get an additional generation of interbreeding. "In the grandkids, some birds had scaled feet, others had big muffs and others were in between, with a range of scales and feathers," Shapiro said in a press statement. "They usually had both.” To Shapiro and his colleagues, this three-way split suggested that there were only a few genes involved in producing feathered feet.

The researchers then ran a number of DNA sequence tests, looking for any genes that might be connected to foot-feather growth. They found two potential culprits: Tbx5 and Pitx1.

Both genes are associated with fore- and hindlimb growth throughout much of the animal kingdom. "Tbx5 is critical for proper forelimb development in all vertebrates—fish [fins], chickens, mice and even humans," Shapiro said. "Mutations in the gene in humans cause Holt-Oram Syndrome, which results in arm defects and heart defects in newborns."

Pitx1, on the other hand, is responsible for making sure that hind limbs, like legs, grow properly.

The thing is, both genes were found in all the grand-birds, regardless of their foot type. The researchers realized that it wasn’t the genes themselves, but their expression, that might be responsible. A DNA sequence in the floofy-footed birds seems to turn down the volume on Pitx1 and turn up Tbx5, resulting in legs that are feathered and sometimes even structured a bit like forelimbs. They are, Shapiro says, “partially wings.”

So what does this mean for the dinosaurs? What was up with their legs? There's still a lot of work to be done, but this was a pretty good, fancy step in the right direction. (A different team of researchers recently attempted to answer that question by genetically manipulating a chicken so that its leg bones developed to resemble those of dinosaurs.)

"Based on what we found in pigeons, the change from scales to feathers can be genetically very simple," Shapiro says. "This can give us some clues about not only how pigeons get feathered feet, but perhaps about how ancient birds lost foot feathers."

This Is the Age When Puppies Reach 'Peak Cuteness'

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]

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


More from mental floss studios