15 Things You Might Not Know About Rhinos

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The rhinoceros is the second largest land mammal on Earth, next to the elephant. It's also one of the most aggressive. But despite its reputation as the bully on the playground, rhinos are vulnerable when it comes to one great danger: humans. Their ranks have drastically dwindled over the past century due to poaching and habitat loss, and conservationists are now trying to save them from extinction. In recognition of Save the Rhinos Day on May 1, here are 15 important facts about nature's knight in armor.

1. THEY'RE GREEK—AT LEAST IN NAME.

Rhinoceros in a field with a pond

The word rhinoceros stems from the Greek words rhino (nose) and keras (horn). So when you shorten the word to "rhino," you're really just saying "nose."

2. A GROUP OF RHINOS IS CALLED A "CRASH."

Three rhinos drinking water

Crash of Rhinos also happens to be an emo band from Derby, England.

3. THEY USED TO BE 16 FEET TALL.

older rhino walking with two younger rhinos

The paraceratherium, a hornless species of ancient rhinoceros that roamed the Earth 30 million years ago, stood over 16 feet tall. Modern rhinos are significantly smaller, of course, but scientists don't really know how they evolved. The white rhino, which grows up to 6 feet tall, is the largest of the five species that exist today. Measuring under 5 feet in height, the smallest is the Sumatran rhino, which is the only hairy species as well as the closest living relative of the extinct woolly rhinoceros.

4. WHITE RHINOS AND BLACK RHINOS ARE ACTUALLY THE SAME COLOR.

two rhinos standing in grass

They're both essentially grayish-brown. One widely spread rumor suggests that white rhinos were originally called wijd (wide) by Dutch settlers in Africa, referring to the animal's wide mouth, which was then mistranslated into English as "white." However, rhino expert Kees Rookmaaker has stated that there is no linguistic evidence to support that tale. It remains a mystery how the white rhino got its name.

5. RHINOS SAY MMWONK WHEN THEY'RE HAPPY.

Indian rhinos are known to make at least 10 distinct sounds, including honks (used during head-to-head fights), bleats (signaling submission), and moo-grunts (used between mothers and calves). Black rhinos use grunts as a greeting and make a mmwonk sound when they're content.

6. THEY HAVE A COMPLICATED RELATIONSHIP WITH THE OXPECKER BIRD.

Oxpecker bird sits on the head of a rhino

Rhinos are often seen with oxpeckers hitching a ride on their backs, but the benefit of these birds is currently debated. The traditional argument is that they snack on bugs and ticks that crawl on the rhino's skin, but in 2000, research on cattle failed to find a consistent benefit to having oxpeckers, while a 2004 study on captive (and tick-free) rhinos found that rather than being helpful, oxpeckers spent much of their time picking at wounds and feasting on the rhino’s blood [PDF]. Meanwhile, other researchers argue that the birds actually do eat ticks and the like. The birds may give the rhinos one additional benefit though: A 2010 experiment found that without oxpeckers, black rhinos were able to detect a person walking up to a rhino 23 percent of the time. With the oxpeckers present that shot up to 97 percent, perhaps explaining why in Swahili, the oxpecker is referred to as the "rhino's guard."

7. THEY'RE LONG-DISTANCE SPRAYERS.

rhino spray urinating

In a show of dominance, alpha male Indian rhinos can spray urine a distance of over 16 feet. This is typically done in the presence of other males or breeding-age females. Other rhinos also spray urine: For males this is typically for marking territory, while female Sumatran rhinos [PDF] have been observed spray urinating 69 times in a 12 hour period before giving birth, and continued this behavior even after the calf was weaned, likely to mask the scent of the calf.

8. THEY COMMUNICATE THROUGH POOP.

rhino sniffing poop

White rhino droppings are unique identifiers, meaning that a rhino can take one whiff of a dung heap and instantly know the animal's age, sex, and reproductive status, according to one study. All white rhinos in a particular area head to the same spot to defecate, called a midden, which is essentially a communal dumping ground.

"We think of dung as just a waste product, but it's really a good way for animals to communicate," Courtney Marneweck, the head of the study, told National Geographic. "There's a lot of information there that we haven't taken advantage of."

9. THEIR FARTS SMELL LIKE SULFUR.

rhino sniffing another rhino's butt

Rhinos are notorious for passing particularly noxious gas, according to the book Does It Fart? The Definitive Field Guide to Animal Flatulence:

"Rhino farts also smell really bad, so much so that they have even given rise to a piece of brewing terminology; when the yeast used to make alcohol through fermentation produces hydrogen sulfide it gives off a horrible sulfur smell, known as a rhino fart."

10. THE MALES CAN GET AGGRESSIVE.

two male rhinos fighting with their horns

Rhinos aren't afraid to use their horns when it comes to matters of the heart. Male black rhinos are particularly aggressive in their pursuit of a mate, and the rate of "mortal combat" among these horned lovers is higher than any other mammal on the planet. About half of males and 30 percent of females die from injuries sustained while fighting.

11. THEY'RE RELATED TO ZEBRAS.

rhinos gathering with zebras

The closest living relatives to rhinos are not elephants or hippos, but rather horses, tapirs, and zebras, all of which are classified as odd-toed ungulates. Rhinos and tapirs walk on three toes, while horses walk on one (which we know as a hoof).

12. THEY HAVE SENSITIVE FEET.

rhino's feet

Speaking of toes, rhinos do have one weak spot. Rhinos typically put most of their weight on their toenails when they walk to avoid wearing out their sensitive feet. This is easy to do in the wild, where marshes and mushy wetlands abound, but when they're brought to zoos, their toenails tend to wear down on hard surfaces like concrete and asphalt. This can lead to swollen, sore, and cracked feet, making them more susceptible to infection. To tackle this issue, one zoo glued modified horseshoes onto a rhino's toes, which you can read about in the book The Rhino With Glue-On Shoes.

13. THEY'RE WALLOWERS.

But not because they're depressed. For a rhino, a nice mud bath is like a day at the spa. It not only helps the animals cool down in hot weather, but it's also great for their skin, helping to ward off pesky insects. Although the animals have a pretty thick dermis, they're surprisingly vulnerable when it comes to bug bites and sunburn.

14. THEIR HORNS ARE MADE OF THE SAME PROTEIN FOUND IN HUMAN FINGERNAILS.

close-up on a rhino's horns

Rhino horns are made up of nothing but keratin, but that doesn't stop poachers from killing thousands of the animals each year and selling their horns on the black market. The horns are fashioned into jewelry and figurines, and in some parts of Asia they're believed to hold healing properties (they don't).

15. THEY RISK EXTINCTION.

man with binoculars in the wild

Just a century ago, there were more than half a million rhinos around the world. Now, around 30,000 survive in the wild, largely due to poaching. All five species of rhino are in danger, but three are considered critically endangered: Sumatran, Javan, and black rhinos. Today, there are about 60 remaining Javan rhinos, fewer than 100 Sumatran rhinos, and about 5000 black rhinos.

There is some good news, though. Thanks to conservation efforts, black and white rhino numbers have increased in recent years, with the white rhino having been "brought back from the brink of extinction," according to the World Wildlife Fund. The organization Save the Rhinos is taking a multi-pronged approach to the issue, working to deploy more field rangers to protect the animals, reduce demand in Asia, and breed rhinos that are currently in captivity.

A Team of Cigarette Butt-Collecting Birds Are Keeping a French Theme Park Litter-Free

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The six rooks pecking at litter within the Puy du Fou theme park in Les Epesses, France, aren't unwelcome pests: They're part of the staff. As AFP reports, the trained birds have been dispatched to clean up garbage and cigarettes butts from the park grounds.

Rooks are a member of the corvid family, a group of intelligent birds that also includes ravens and crows. At Puy du Fou, an educational amusement park with attractions inspired by various periods from French history, the rooks will flit around park, pick up any bits of litter that haven't been properly disposed of, and deliver them to a receptacle in exchange for a treat. At least that's how the system is set up to work: The full team of six rooks has only been on the job since August 13.

Employing birds as trash collectors may seem far-fetched, but the experiment has precedent. The Dutch startup Crowded Cities recently started training crows to gather cigarette butts using a vending machine-like device. Once the crows were taught to associate the rig with free peanuts, the machine was tweaked so that it only dispensed food when the crow nudged a cigarette butt resting on a ledge into the receptacle. The cigarette butts were eventually removed, and the birds figured out that they had to find the litter in the wild if they wanted to continue receiving their snacks.

Crowded Cities had planned to conduct more research on the method's effectiveness, as well as the potentially harmful effects of tobacco on crows, before bringing their vending machines to public spaces. Puy du Fou, meanwhile, has become one of the first—if not the first—businesses to fully implement the strategy on a major scale.

Even if it doesn't prove to be practical, Puy du Fou president Nicolas de Villiers told AFP that cleaning up the park is only part of the goal. He also hopes the birds will demonstrate that "nature itself can teach us to take care of the environment."

[h/t AFP]

Wasps Are Getting Drunk and Terrorizing People in England

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Go home, wasps. You’re drunk.

Thousands of “boozy wasps” are terrorizing the UK after imbibing the nectar of fermented fruit and cider left behind at pub gardens, Travel + Leisure reports. Experts warn that there’s a greater risk of getting stung at this time of year, especially while boozing outdoors or eating sweet foods.

The sudden change in diet highlights an issue with the insects' food supply: Wasps typically drink a kind of sugar-spit produced by larvae, but the hive queens have already stopped laying larvae by this time of year, and wasps have been unable to get their fill. They also carry a genetic trait that makes them go crazy for sugary foods and alcohol, and other factors have escalated the problem. For one, last year's cold winter translated to an early wasp season, which allowed them to build larger-than-normal nests.

"Wasps have built absolutely massive nests and, now that all the larvae have grown up and the queen has stopped laying eggs, the colonies have a workforce with nothing to do—and nothing to eat," pest control expert Shane Jones told the Daily Mail. "So they go down to the pub, obviously."

What they really want is sugar, which can be found in fermented fruit, cider, and fruity beers. Because wasps are lightweights, just one sip will get them drunk—and you don’t want to see them when they’re tipsy. "Wasps can't handle their booze, so they get tanked-up and fighty—like lager louts,” Jones says. Alcohol can make the insects more irritable and more likely to sting people.

The best way to avoid the problem, according to Dee Ward-Thompson, technical manager at the British Pest Control Association, is to keep the sugary goodies they're craving out of sight. “Maybe the most influential factor on wasp numbers is when people do not dispose of their waste properly, especially food with a high sugar content, such as fruit," Ward-Thompson told the Nottingham Post. “We always advise waste to be securely bagged and held within a clean container, away from where young children might play.”

[h/t Travel + Leisure]

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