14 Zany Facts About Zebras

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Zebras are more than just striped members of the horse family. Some are rugged mountaineers, some have spots instead of stripes, and some of them bark like dogs. Read on to discover these and other bizarre facts about zebras. 

1. A ZEBRA’S COAT IS A GIANT BAR CODE—AND WE CAN SCAN IT.

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Every zebra has a unique pattern of stripes. And scientists can use the patterns like bar codes to identify individuals in a herd and keep track of them over time.

Compared to today’s methods, the first efforts to identify zebras by their stripes were pretty low-tech. Hans and Ute Klingel, a husband and wife team, pioneered stripe recognition with Grevy’s zebras back in the 1960s. First, they photographed a bunch of zebras. Then they developed the pictures in a dark room they erected right in the field. Next, they created a card index with coded, hand-written notes on each animal’s pattern. See a few of their cards here.

These days, special software can scan images of zebras and identify individuals by “reading” their stripes like bar codes. It can even compensate for changes in posture and weight, including pregnancy. 

2. ZEBRA STRIPES MAY SERVE AS BUG SPRAY OR AIR CONDITIONING. 

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For decades and decades, scientists have wondered why zebras have stripes. One prevailing theory held that the stripes confused predators, making it harder for, say, a lion to pick out an individual zebra from a stampeding herd. 

Lately, more intriguing theories have emerged. Some scientists think that stripes keep zebras cooler. The dark stripes soak up more sunlight than the light ones, and this stirs up eddies of wind that swirl heat away. Other researchers discovered that biting flies avoid striped patterns. And the two theories might be linked: Biting flies prefer hot temperatures, so they may be less likely to bite a cooler zebra. 

3. BUT ZEBRAS DON’T ALWAYS HAVE BLACK AND WHITE STRIPES. 

Yathin S Krishnappavia Wikimedia // CC BY-SA 3.0

There are three species of zebra, and many subspecies. They come in different sizes, body shapes, stripe patterns—and, to a certain extent, even colors. The white stripes can verge on cream and the dark stripes can be black or brown. Some subspecies have pale, shadowy stripes between the larger dark ones. Plus, there are all sorts of mutations and variations. The occasional zebra has spots and some are so pale they're almost entirely white

4. MOUNTAIN ZEBRAS ARE RUGGED.

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One of the three zebra species, the mountain zebra, lives mostly in hilly, rocky places in South Africa and nearby Namibia. It has especially hard, sharp hooves that help it climb and keep its balance in rugged terrain. And while this rugged critter can’t grow a mountain man beard, it does have a bizarre, prominent neck flap called a dewlap.

5. PLAINS ZEBRAS ARE SMALL AND NUMEROUS. 

Walter Voigts via Wikimedia // CC BY-SA 3.0

Plains zebras are the smallest. They’re also the most abundant—in fact, they’re the most numerous of all the wild members of the horse family. They roam across much of southeastern Africa. 

Plains zebras come in all sorts of subspecies, and there’s a lot of coat variation between. For example, as you travel farther south across Africa, plains zebras will have fewer stripes on their legs. Nobody’s sure why, but it may have something to do with temperature or populations of those biting flies. 

6. GREVY’S ZEBRAS ARE LARGE AND PRESIDENTIAL. 

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Found in Kenya and Ethiopia, Grevy’s zebras have a more donkey-like shape, with huge round ears. They’re the largest wild members of the horse family, and can weigh up to 990 lbs. (Yes, domestic horses get much bigger, but that’s because we’ve spent thousands of years breeding them into all sorts of shapes and sizes; some are enormous.) 

These zebras are named after a President of France. In 1882, Emperor of Abyssinia (now Ethiopia) Menelik II presented one as a gift to French President Jules Grévy. Ever since then, they’ve been named in honor of Grévy.

7. TO TELL THEM APART, LOOK AT THE BUTT.

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There are plenty of useful field marks for distinguishing the zebra species, but one is to look at the pattern on the rump. Mountain zebras have a “gridiron” pattern of small stripes above their tail. Plains zebras have broad bands across the rear. Grevy’s zebras have a sort of triangle pattern on the rump, with lots of small lines near the tail. Once you learn these differences, you’ll tell them apart with ease—just be sure to explain to your safari companions why you’re so fascinated by zebra butts. 

8. ONE EXTINCT ZEBRA HAD A STRIPE-FREE BUTT. 

A quagga at the London Zoo in 1870. Image credit: Frederick York via Wikimedia // Public Domain

The quagga, a remarkable subspecies of the plains zebra, was mostly yellow-brown and un-striped below its shoulders. Native to South Africa, it was driven to extinction by European settlers and hunters. The last quagga died at the Amsterdam Zoo in 1883.

Incredibly, a group called the Quagga Project, based in South Africa, has been working to resurrect this subspecies. They pick plains zebras that look the most quagga-like and breed them together, hoping to awaken any quagga genes that may still be present. The project has drawn criticism, however: some argue that recreating an animal’s appearance isn’t the same as restoring its unique behavior and ecological role.

9. ZEBRA ROMANCE ISN’T EASY.

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Mountain zebras and plains zebras live in small groups consisting of one stallion (male) and a handful of mares (females). You may notice that this ratio is a little askew. Where do the “extra” males go? Stallions that haven’t secured a herd will gather to bro down in roving bachelor bands. Some of those bachelors may try to take over a pre-existing herd, but it's no easy task. First, a bachelor must defeat the lead stallion. Then, he waits for the females to warm up to him—which may take up to three years.

And then there’s the Grevy’s zebra. A mature Grevy’s stallion doesn’t seek to command a herd of females—he stakes out some land. Ideally, he claims a territory that has some nice food and water. Then he hunkers down and plays the waiting game. Female Grevy’s zebras are wanderers, and the stallion is hoping that the ladies will visit for some sustenance and perhaps romance. Young Grevy’s males who don’t have territories will buddy up into groups and also wander. Those territorial stallions tolerate their presence—that is, until a receptive female wanders by. Then things get ugly. (Don't click on that link unless you're comfortable with graphic zebra romance.)

10. DON’T RIDE A ZEBRA. 

No, really: don’t. Humans domesticated horses thousands of years ago, modifying their appearance and behavior and turning them into compliant, beloved companions. But zebras were never domesticated. It’s sort of like the difference between a poodle and a wolf. There are several reasons that humans domesticated horses instead of zebras, including a zebra’s ducking reflex. Watch this video to learn more.

11. ZEBRAS NEIGH, BRAY, AND … BARK.

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Zebras make all sorts of weird sounds. Mountain zebras whinny like a horse, Grevy’s zebras bray like a donkey, and plains zebras bark like dogs. Alarmed stallions may squeal or snort, and happy zebras may push air between their lips when they’re eating. 

12. ZEBRAS CAN MAKE ZORSES, ZONIES, ZEDONKS, AND MORE. 

A zedonk, or hybrid zebra-donkey. Image credit: Getty Images

Zebras can breed with other members of the horse family. The offspring come in an amazing variety of semi-striped patterns, and are usually sterile (meaning they can’t have young). Zorses are the offspring of horse stallions and zebra mares. Zedonks are the products of zebra stallions and donkey mares. Zonies come from zebras and ponies. And there are many more bizarre possibilities

13. ZEBRAS ARE IN TROUBLE.

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Two out of the three zebra species aren’t doing so well. Grevy’s zebras are in the deepest doo-doo: habitat loss, hunting, competition for food and water with domestic grazing animals, and disease have all taken their toll. The International Union for Conservation of Nature (IUCN) labels them endangered and says they’ve “undergone one of the most substantial reductions of range of any African mammal.” There are only about 2000 of these big-eared zebras left.

Mountain zebras face similar threats, and are listed as Vulnerable, which is one rung better than Endangered. There are about 9000 left. 

Plains zebras, on the other hand, are in pretty okay shape. Despite local declines from habitat loss and hunting, their population is fairly stable

Preserving zebras is important because they’re amazing, and because they’re food for majestic predators like lions. But also… 

14. PLAINS ZEBRAS MAKE GRASSLANDS TASTIER.

For pickier grazers such as Thomson’s gazelles and wildebeest, zebras are a huge boon. Those striped heroes have special digestive systems that can quickly process lower-quality forage. Plains zebras are often the first to enter an un-grazed grassy area. They’ll munch on older, harder, less nutritious plants that other grazers can’t eat. Once the old stuff is cleared out, tender new growth pops up. More selective grazers will then wander in and eat the good stuff.

Why Do Bats Hang Upside Down?

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iStock.com/CraigRJD

Stefan Pociask:

The age-old question of upside down bats. Yes, it is awfully weird that there is an animal—a mammal even—that hangs upside down. Sure, some monkeys do it when they're just monkeying around. And a few other tree climbers, like margays, hang upside down if they are reaching for something or—again, like the margay cat—may actually even hunt that way ... But bats are the only animals that actually spend most of their time hanging upside down: feeding this way, raising their young this way, and, yes, sleeping or roosting this way.

There is actually a very good and sensible reason why they do this: They have to hang upside down so that they can fly.

First off, we have to acknowledge that bats are not birds, nor are they insects. These are the other two animals that have true powered flight (as opposed to gliding). The difference between bat flight and bird or insect flight is weight—specifically, the ratio of weight to lift-capacity of the wings. If you walk up to a bird or insect, most species will be able to fly right up into the air from a motionless position, and do it quickly.

Bats, on the other hand (or, other wing), can’t do that. They have a lot of difficulty taking off from the ground (not that they can’t do it ... it’s just more difficult). Insects and birds often actually jump into the air to give them a start in the right direction, then their powerful wings take them up, up, and away.

Birds have hollow bones; bats don’t. Insects are made of lightweight chitin or soft, light tissue; bats aren’t. And bats don’t have what you could call "powerful" wings. These amazing creatures are mammals, after all. The only flying mammals. Nature found a way to evolve such an unlikely thing as a flying mammal, so some compromises had to be made. Bats, once airborne, manage perfectly well in the air, and can literally fly circles around most birds in flight. The problem is in first getting off the ground.

To compensate for the extra weight that mammals must have, to compensate for the problem of getting off the ground, evolution found another way for bats to transition from being motionless to immediately being able to fly when necessary. Evolution said, “How about if we drop them from above? That way they are immediately in the air, and all they need to do is start flapping."

It was a great idea, as it turns out. Except bat feet aren’t any good for perching on a branch. They are mammals, not birds, so their musculature, their bones, and their tendons are set up in a completely different way. When a bird squats down on a branch, their tendons actually lock their toes into an even tighter grip on the perch. It happens automatically. That’s part of being a bird, and is universal. That’s why they don’t fall off in their sleep.

Bats, as mammals, are set up differently. Therefore, to compensate for that fact, nature said, “How about if we have them hang upside down? That way, their tendons will actually pull their toes closed, just like a bird does from the opposite direction.” So that’s what evolved. Bats hang from the bottom of something, and all they have to do is "let go" and they are instantly flying. In fact, with this gravity-assist method, they can achieve instant flight even faster than birds, who have to work against gravity.

Side note: In case you were wondering how bats poop and pee while upside down ... First off, pooping is no big deal. Bat poop looks like tiny grains of rice; if they are hanging, it just falls to the floor of the bat cave as guano. Pee, however ... well, they have that covered too. They just “hold it” until they are flying.

So there you go. Bats sleep hanging upside down because they are mammals and can’t take off into the air like birds can (at least not without difficulty). But, if they're hanging, all they do is let go.

Makes total sense, right?

Now, having said all that about upside down bats, I must mention the following: Not all of the 1240-plus species of bats do hang upside down. There are exceptions—about six of them, within two different families. One is in South America (Thyropteridae) and the other is in Madagascar (Myzopodidae). The Myzopodidae, which includes just one species, is exceedingly rare.

So it turns out that these bats roost inside the tubes of young, unfurled banana leaves and other similar large leaves. When they attach themselves to the inside of this rolled leaf, they do it head-up. The problem with living inside of rolled-up leaves is that within a few days, these leaves will continue growing, and eventually open up. Whenever that happens, the whole group of bats has to pick up and move to another home. Over and over again. All six of these species of rare bats have a suction cup on each wrist and ankle, and they use these to attach to the smooth surface of the inside of the leaf tube. Evolution: the more you learn, the more amazing it becomes.

This post originally appeared on Quora. Click here to view.

Sorry, But Last Month's Polar Vortex Didn't Wipe Out 95 Percent of Stink Bugs

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iStock.com/drnadig

In the wake of the polar vortex that brought bone-chilling temperatures to the Midwest and Northeast U.S. last month, a silver lining appeared to emerge. Multiple media outlets recently reported that the weather phenomenon may have wiped out as many as 95 percent of brown marmorated stink bugs in areas that weren't accustomed to such frigid conditions.

Unless you like having your home smell like the musky, burnt-cilantro scent of squished stink bugs, we have some bad news: Those reports are not entirely accurate. According to KDKA Radio in Pittsburgh, the Virginia Tech lab experiment that has been widely cited in these articles is a little outdated, having been conducted in 2014.

At the time, it appeared to be a promising find. Researchers from the university had collected stink bugs, placed them in insulated buckets, and waited to see if they'd survive a particularly cold spell. Even though the insects were in a dormant state called diapause, 95 percent of them died when a polar vortex hit the region. That led entomology professor Thomas Kuhar to tell The Washington Post in 2014 that “there should be significant mortality of BMSB (brown marmorated stink bugs) and many other overwinter insects this year."

However, in an email to Mental Floss, Kuhar says the rehashing of "some media misquotes from 2014" led to these too-good-to-be-true reports being recirculated this week. "There is no new research on this topic," he writes. Furthermore, the lab experiment can't easily be applied to real-life scenarios because stink bugs tend to seek shelter during the winter. "Severe sub-freezing temperatures will negatively impact winter survival of these stink bugs if they were unable to find suitable shelter such as inside of houses and sheds," he writes.

These sentiments were echoed by entomologist Chad Gore of Ehrlich Pest Control, who spoke with KDKA Radio. "When they can find that shelter, they can survive the winter. Those that are exposed, they will freeze and we won’t have to worry about them," he said.

But is there still a chance we will see fewer stink bugs in the spring? Gore says don't count on it. "I’d love to be able to reassure everybody and say that 95 percent of all of our stink bugs are going to be gone, but that’s just not going to be the case," he said. "We’re still going to see them."

Even though stink bugs don't bite and are basically harmless (though they sometimes trigger allergic reactions), they can be difficult to trap once they've found a way into one's house. The invasive species is also harmful to crops—especially grapes—and sometimes end up getting pulverized and fermented in red wine. Suffice it to say, a lot of people would be happy if the pests suddenly disappeared. For now, though, we'll have to keep on dreaming.

[h/t KDKA Radio]

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