Scientist Says Weak Bones Drove Woolly Mammoths to Extinction

Why don’t we have woolly mammoths anymore? Was it climate change? Did early humans eat them to death? Maybe. Or maybe they just fell down. A new paper suggests that bone disease weakened the prehistoric giants until they could no longer support their own body weight.

Theories on the mammoths’ disappearance have long jockeyed for supremacy. Most attention has focused on two likely culprits: global warming and hunting. Each new study refutes the last, leading to headlines like “What Killed Off the Woolly Mammoth? Climate Change,” followed just a few months later with “Humans Definitely Killed Off Woolly Mammoths.”

What if everybody’s right?

Paleontologist Sergei Leshchinskiy of Russia's Tomsk State University believes that a shifting climate led to changes in the landscape, which in turn caused a decline in available minerals. In a recent paper in the journal Archaeological and Anthropological Sciences, Leshchinskiy argues that these nutrient deficiencies weakened the mammoths’ bones, making them slower and weaker, and therefore easier to hunt. 

Image Credit: ©TSU

Leshchinskiy analyzed more than 23,500 mammoth bones and teeth using a magnifying glass, stereomicroscope, and scanning electron microscope, as well as x-rays and densitometry. The bones had been collected from mineral-rich sites in the Czech Republic, Poland, and Russia. These areas are called the beast solonetz,which Leshchinskiy translates as "a ground surface area characterized by a high content of certain macro- and micro-elements." Like nutrient watering holes, the rocks and soil of the beast solonetz sites provided animals like mammoths with the minerals they needed. 

But something went wrong. Leshchinskiy found signs of osteoporosis and other bone diseases in a full 90 percent of the specimens he examined. Holding up a mammoth is a big job, and these bones were just not strong enough. Even the bones from baby mammoths were brittle and weak, which suggests their mothers weren’t getting the nutrients they needed.

So what changed? The landscape. Over thousands of years, as continents shifted and the planet warmed, some areas were swamped, and others went dry. Floods leached essential nutrients like calcium, magnesium, zinc, and sodium from the soil of the beast solonetz. The supply of dirt-flavored multivitamins dried up, says Leshchinskiy, and the mammoths’ skeletons began to weaken.

Conquering a mammoth in its prime would have been no easy feat for our ancestors. A mammoth with a broken leg, on the other hand, was as good as dinner. Leshchinskiy’s results are specific to Eurasia, but he believes the same scenario may have been true elsewhere in the world, including North America.

Mark Ralston, AFP/Getty Images
How a Hairdresser Found a Way to Fight Oil Spills With Hair Clippings
Mark Ralston, AFP/Getty Images
Mark Ralston, AFP/Getty Images

The Exxon Valdez oil tanker made global news in 1989 when it dumped millions of gallons of crude oil into the waters off Alaska's coast. As experts were figuring out the best ways to handle the ecological disaster, a hairdresser from Alabama named Phil McCroy was tinkering with ideas of his own. His solution, a stocking stuffed with hair clippings, was an early version of a clean-up method that's used at real oil spill sites today, according to Vox.

Hair booms are sock-like tubes stuffed with recycled hair, fur, and wool clippings. Hair naturally soaks up oil; most of the time it's sebum, an oil secreted from our sebaceous glands, but it will attract crude oil as well. When hair booms are dragged through waters slicked with oil, they sop up all of that pollution in a way that's gentle on the environment.

The same properties that make hair a great clean-up tool at spills are also what make animals vulnerable. Marine life that depends on clean fur to stay warm can die if their coats are stained with oil that's hard to wash off. Footage of an otter covered in oil was actually what inspired Phil McCroy to come up with his hair-based invention.

Check out the full story from Vox in the video below.

[h/t Vox]

A New Chew Toy Will Help Your Dog Brush Its Own Teeth

Few pet owners are willing to sit down and brush their pet's teeth on a regular basis. (Most of us can barely convince ourselves to floss our own teeth, after all.) Even fewer pets are willing to sit calmly and let it happen. But pet dental care matters: I’ve personally spent more than $1000 in the last few years dealing with the fact that my cat’s teeth are rotting out of her head.

For dog owners struggling to brush poor Fido’s teeth, there’s a slightly better option. Bristly, a product currently being funded on Kickstarter, is a chew toy that acts as a toothbrush. The rubber stick, which can be slathered with doggie toothpaste, is outfitted with bristles that brush your dog’s teeth as it plays.

A French bulldog chews on a Bristly toy.

Designed so your dog can use it without you lifting a finger, it’s shaped like a little pogo stick, with a flattened base that allows dogs to stabilize it with their paws as they hack at the bristled stick with their teeth. The bristles are coated in a meat flavoring to encourage dogs to chew.

An estimated 80 percent of dogs over the age of 3 have some kind of dental disease, so the chances that your dog could use some extra dental attention is very high. In addition to staving off expensive vet bills, brushing your dog's teeth can improve their smelly breath.

Bristly comes in three sizes as well as in a heavy-duty version made for dogs who are prone to ripping through anything they can get their jaws around. A Bristly stick costs $29 and is scheduled to start shipping in October. Get it here.


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