15 Things You Might Not Know About Rhinos

iStock
iStock

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.

This Wall Chart Shows Almost 130 Species of Shark—All Drawn to Scale

Pop Chart Lab
Pop Chart Lab

Shark Week may be over, but who says you can’t celebrate sharp-toothed predators year-round? Pop Chart Lab has released a new wall print featuring nearly 130 species of selachimorpha, a taxonomic superorder of fish that includes all sharks.

The shark chart
Pop Chart Lab

Called “The Spectacular Survey of Sharks,” the chart lists each shark by its family classification, order, and superorder. An evolutionary timeline is also included in the top corner to provide some context for how many millions of years old some of these creatures are. The sharks are drawn to scale, from the large but friendly whale shark down to the little ninja lanternsharka species that lives in the deep ocean, glows in the dark, and wasn’t discovered until 2015.

You’ll find the popular great white, of course, as well as rare and elusive species like the megamouth, which has been spotted fewer than 100 times. This is just a sampling, though. According to World Atlas, there are more than 440 known species of shark—plus some that probably haven't been discovered yet.

The wall chart, priced at $29 for an 18” x 24” print, can be pre-ordered on Pop Chart Lab’s website. Shipping begins on August 27.

Can You Really Suck the Poison Out of a Snakebite?

iStock
iStock

Should you find yourself in a snake-infested area and unlucky enough to get bitten, what’s the best course of action? You might have been taught the old cowboy trick of applying a tourniquet and using a blade to cut the bite wound in order to suck out the poison. It certainly looks dramatic, but does it really work? According to the World Health Organization, approximately 5.4 million people are bitten by snakes each year worldwide, about 81,000 to 138,000 of which are fatal. That’s a lot of deaths that could have been prevented if the remedy were really that simple.

Unfortunately the "cut and suck" method was discredited a few decades ago, when research proved it to be counterproductive. Venom spreads through the victim’s system so quickly, there’s no hope of sucking out a sufficient volume to make any difference. Cutting and sucking the wound only serves to increase the risk of infection and can cause further tissue damage. A tourniquet is also dangerous, as it cuts off the blood flow and leaves the venom concentrated in one area of the body. In worst-case scenarios, it could cost someone a limb.

Nowadays, it's recommended not to touch the wound and seek immediate medical assistance, while trying to remain calm (easier said than done). The Mayo Clinic suggests that the victim remove any tight clothing in the event they start to swell, and to avoid any caffeine or alcohol, which can increase your heart rate, and don't take any drugs or pain relievers. It's also smart to remember what the snake looks like so you can describe it once you receive the proper medical attention.

Venomous species tend to have cat-like elliptical pupils, while non-venomous snakes have round pupils. Another clue is the shape of the bite wound. Venomous snakes generally leave two deep puncture wounds, whereas non-venomous varieties tend to leave a horseshoe-shaped ring of shallow puncture marks. To be on the safe side, do a little research before you go out into the wilderness to see if there are any snake species you should be particularly cautious of in the area.

It’s also worth noting that up to 25 percent of bites from venomous snakes are actually "dry" bites, meaning they contain no venom at all. This is because snakes can control how much venom they release with each bite, so if you look too big to eat, they may well decide not to waste their precious load on you and save it for their next meal instead.

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