Some Japanese Monkeys Can’t Taste Bitterness

The five major tastes—sweet, sour, salty, umami (or savory), and bitter—were long assumed to be universal. Each flavor delivers important information to its taster: sweet fruits are generally ripe and safe to eat but bitter foods may be poison and probably shouldn’t be ingested.

Scientists believed that the ability to taste bitterness was crucial to survival. And while that may still be true for most species, being unable to taste bitterness might be an advantage for the snow monkeys of Kii, Japan.

Researchers at Kyoto University conducted genetic tests on more than 600 snow monkeys, or macaques, from around Japan. They found that macaques from the Kii region were far more likely than their compatriots to have lost the gene that enables them to taste bitterness.

And the Kii snow monkeys' loss of the gene over generations means that their inability to taste bitterness was somehow an asset and that monkeys without the gene were more likely to survive and reproduce.

Analyzed by itself, this regional genetic quirk doesn’t make much sense. But the researchers realized that the super-bitter fruit Citrus tachibana had originated in the Kii region. Local monkeys would have been at quite an advantage if they could eat the fruit.

In recent years, scientists have discovered that animals have a range of tasting abilities. Penguins can’t taste bitter, sweet, or umami flavors. Cats are especially sensitive to bitter foods, which may explain their reputation as picky eaters. Frogs have more bitter taste receptors than chickens.

Like so many other things in science and in life, taste is complicated.

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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