People Can't Tell Their Toes Apart Without Looking

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iStock

There are few things in life as familiar as your own body, but a study published in the journal Perception shows that our sense of self starts to disappear when we lose our sense of sight. In fact, the scientists report that people have a difficult time identifying their own toes when their eyes are closed.

The study participants were touched on their fingers and toes without their being able to see which digit was being touched, and then asked to identify the digit being singled out.

Fingers were a cinch, with testers identifying the correct one about 99 percent of the time. Accuracy dropped slightly, to 94 percent, for the big and pinky toes. But it plummeted with the three middle toes, to as low as 57 percent. These little piggies gave testers the toughest time.

“The key issue was distinguishing between the second and third toes [the toes next to the big toe],” said Dr. Nela Cicmil of Oxford's Department of Physiology.

While some did better than others, every participant had some degree of difficulty in identifying the correct toes. This sort of misidentification is called “agnosia.” The National Institute of Neurological Disorders and Stroke describes it as “an inability to recognize and identify objects or persons.”

Not only did people share the struggle to correctly identify their digits, they exhibited a similar pattern in which the second toe was believed to be the third, and the third toe was believed to be the fourth. The troubles were even worse when testing the nondominant foot. The most surprising discovery: Nearly half of the testers reported feeling as if one toe were gone.

The results could be a valuable tool for understanding more about how agnosia or other body misperceptions work. Moreover, the fact that the healthy humans in the study still had trouble with what might have been considered an easy task could also hold answers for future brain-damage testing. 

Lítla Dímun: The Smallest of the Faroe Islands Has Its Very Own Cloud

While some islands are known for their unusual geography or unique history, Lítla Dímun is notable for its weather. The island, which is the smallest of Denmark's Faroe Islands chain, is often capped by a lens-shaped cloud, making it resemble a scene from a fairytale.

According to Mental Floss's own Kerry Wolfe writing for Atlas Obscura, the cloud floating above Lítla Dímun is a lenticular cloud. This type of cloud forms when moist air flows over a protruding geological feature, like a mountain top. When the wind moving up the landmass hits the air current directly above it, a sort of wave is created on the downwind side of the mountain. The moist air falling down this wave evaporates and then condenses into a large, flying-saucer-shaped cloud atop the mountain peak as a result.

Another factor that makes Lítla Dímun distinct is that it's the only one of the 18 main Faroe Islands without human inhabitants. Visitors to the mystical location will instead find a thriving population of sheep. Originally, Lítla Dímun was home to a group of feral sheep likely dating back to the Neolithic era. But they were hunted to extinction in the 19th century. Domesticated sheep were introduced there around the same time, and today, farmers visit the island once a year to round up their flocks.

One of the few signs of human life are the ropes farmers use to scale the cliff faces bordering the island. Even if you have rock-climbing skills, Lítla Dímun may be dangerous to visit. A boat ride to the rocky shore is only possible when the surrounding sea is calm.

[h/t Atlas Obscura]

Why Are Sloths So Slow?

Sloths have little problem holding still for nature photographers.
Sloths have little problem holding still for nature photographers.
Geoview/iStock via Getty Images

When it comes to physical activity, few animals have as maligned a reputation as the sloth. The six sloth species, which call Brazil and Panama home, move with no urgency, having seemingly adapted to an existence that allows for a life lived in slow motion. But what makes sloths so sedate? And what horrible, poop-related price must they pay in order to maintain life in the slow lane?

According to HowStuffWorks, the sloth’s limited movements are primarily the result of their diet. Residing mainly in the canopy vines of Central and South American forests, sloths dine out on leaves, fruits, and buds. With virtually no fat or protein, sloths conserve energy by taking a leisurely approach to life. On average, a sloth will climb or travel roughly 125 feet per day. On land, it takes them roughly one minute to move just one foot.

A sloth’s digestive system matches their locomotion. After munching leaves using their lips—they have no incisors—it can take up to a month for their meals to be fully digested. And a sloth's metabolic rate is 40 to 45 percent slower than most mammals' to help compensate for their low caloric intake. With so little fuel to burn, a sloth makes the most of it.

Deliberate movement shouldn’t be confused for weakness, however. Sloths can hang from branches for hours, showing off some impressive stamina. And because they spend most of their time high up in trees, they have no need for rapid movement to evade predators.

There is, however, one major downside to the sloth's leisurely lifestyle. Owing to their meager diet, they typically only have to poop once per week. Like going in a public bathroom, this can be a stressful event, as it means going to the ground and risking detection by predators—which puts their lives on the line. Worse, that slow bowel motility means they’re trying to push out nearly one-third of their body weight in feces at a time. It's something to consider the next time you feel envious of their chill lifestyle.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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