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© Monica Jurik, The Field Museum
© Monica Jurik, The Field Museum

Researchers Reclassify Itsy-Bitsy, Prehistoric “Beardogs”

© Monica Jurik, The Field Museum
© Monica Jurik, The Field Museum

Beardogs were neither bears nor dogs. But they might have been the forebears of both. Scientists at Chicago’s Field Museum say two specimens of the Chihuahua-sized animals have just rearranged the branches of the carnivore family tree. A report on the new classifications was published today in the journal Royal Society Open Science.

The beardogs, also known as the amphicyonids, were a family of sturdy, four-footed carnivores that emerged around 40 million years ago. They were a diverse group, ranging widely in size and shape. Some were huge and bearlike; others, like the Field Museum’s fossils, would have maxed out at about 11 pounds.

Shortly after joining the Field Museum, paleontologist Susumu Tomiya decided to take a stroll through the museum’s collections. He was in a room of type specimens—that is, specimens used as perfect examples of their species—when he saw something strange: a carnivore with funny teeth.

“There were beautiful jaws of a small carnivore,” he said in a statement, “but the genus the specimen had been assigned to didn’t seem to fit some of the features on the teeth. It made me suspect that it belonged to a very different group of carnivores.”

The teeth of pure carnivores are sharp so their owners can puncture, bite, tear, and chew tough flesh. But some of the teeth in front of Tomiya had flattened areas, as though they had been used for crushing and grinding. The beardog to whom they belonged, a species called Miacis australis, was supposed to have been on an all-meat diet. Something wasn’t right.

Tomiya kept looking. In the collections at the University of Texas, he found another weird specimen: partial remains from a related beardog called Miacis cognitus, taken from the same rock formation as M. australis’s remains. The second specimen’s lower jaw was missing, but the back of its head was intact.

Tomiya and his coauthor Jack Tseng of the University of Buffalo then used a computed tomography (CT) scanner to create 3D visualizations of the inside of M. cognitus’s skull. They were especially interested in the area around the inner ear, which can often be used to determine relationships between carnivore species.

They found that the two species were closely related and near-contemporaries that likely lived around 37 or 38 million years ago. These were early, early creatures indeed—so far back in the tree of life that they could be called the ancestors of both bears and dogs. And seals. And weasels.

Both specimens had also been classified wrong. Based on the dental and CT evidence, Tomiya and Tseng reassigned M. australis to the genus Gustafsonia and M. cognitus to the genus Angelarctocyon.

The two beardogs’ reassignment has significance beyond their species, Tomiya said: “Studying how the diversity of beardogs waxed and waned over time could tell us about larger patterns in carnivore evolution.”

And while the two specimens are long dead and gone, they still have a lot to tell us about the history of our planet.

Gustafsonia and Angelarctocyon lived at a time when North America was transitioning from a subtropical climate to a cooler, drier climate,” Tomiya said. “There were big changes happening in the landscape, forests were probably opening up, and the fossil assemblages including these beardogs can tell us about what kinds of animals did well in that environmental context.”

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Animals
The Simple Way to Protect Your Dog From Dangerous Rock Salt
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iStock

Winter can be a tough time for dogs. The cold weather usually means there are fewer opportunities for walks and more embarrassing accessories for them to wear. But the biggest threat to canines this time of year is one pet owners may not notice: the dangerous rock salt coating the streets and sidewalks. If you live someplace where this is a problem, here are the steps you need to take to keep your pooch safe until the weather warms up, according to Life Hacker.

Rock salt poses two major hazards to pets: damage to their feet and poisoning from ingestion. The first is the one most pet owners are aware of. Not only do large grains of salt hurt when they get stuck in a dog’s paws, but they can also lead to frostbite and chemical burns due to the de-icing process at work. The easiest way to prevent this is by covering your dog’s paws before taking them outside. Dog booties get the job done, as do protective balms and waxes that can be applied directly to their pads.

The second danger is a little harder to anticipate. The only way you can stop your dog from eating rock salt from the ground is to keep a close eye on them. Does your dog seem a little too interested in a puddle or a mound of snow? Encourage them to move on before they have a chance to take a lick.

If, for some reason, you forget to follow the steps above and your pet has a bad encounter with some winter salt, don’t panic. For salty feet, soak your dog's paws in warm water once you get inside to wash away any remaining grit. If your dog exhibits symptoms like vomiting, diarrhea, and disorientation and you suspect they’ve ingested rock salt, contact your vet right away.

Even with the proper protection, winter can still create an unsafe environment for dogs. Check out this handy chart to determine when it’s too cold to take them for a walk.

[h/t Life Hacker]

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© Museum of Fine Arts, Boston
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Boston's Museum of Fine Arts Hires Puppy to Sniff Out Art-Munching Bugs
© Museum of Fine Arts, Boston
© Museum of Fine Arts, Boston

Some dogs are qualified to work at hospitals, fire departments, and airports, but one place you don’t normally see a pooch is in the halls of a fine art museum. The Museum of Fine Arts, Boston is changing that: As The Boston Globe reports, a young Weimaraner named Riley is the institution’s newest volunteer.

Even without a background in art restoration, Riley will be essential in maintaining the quality of the museum's masterpieces. His job is to sniff out the wood- and canvas-munching pests lurking in the museum’s collection. During the next few months, Riley will be trained to identify the scents of bugs that pose the biggest threat to the museum’s paintings and other artifacts. (Moths, termites, and beetles are some of the worst offenders.)

Some infestations can be spotted with the naked eye, but when that's impossible, the museum staff will rely on Riley to draw attention to the problem after inspecting an object. From there, staff members can examine the piece more closely and pinpoint the source before it spreads.

Riley is just one additional resource for the MFA’s existing pest control program. As far as the museum knows, it's rare for institutions facing similar problems to hire canine help. If the experiment is successful, bug-sniffing dogs may become a common sight in art museums around the world.

[h/t The Boston Globe]

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