13 Chill Facts About Sloths

iStock.com/janossygergely
iStock.com/janossygergely

Sloths seem to be everyone's "spirit animal." They get to eat, sleep, and hang out in trees all day, going about their business without a care in the world. Or at least that's how it looks. As it turns out, there are plenty of good reasons why sloths are so sluggish—and laziness isn't one of them. Here are 13 things you should know about the world's slowest animal.

1. TWO-TOED AND THREE-TOED SLOTHS AREN'T ALL THAT SIMILAR.

A baby two-toed sloth
iStock.com/wekeli

The cute little babe pictured above is a two-toed sloth, of which there are two species belonging to the Megalonychidae family. The four species of three-toed sloths, on the other hand, are part of the Bradypodidae family. The two groups are only distant relatives and have a few notable differences between them. While three-toed sloths are active in the daytime, two-toed sloths are nocturnal creatures. Three-toed sloths are also smaller and slower than their two-toed counterparts.

2. BOTH HAVE THREE TOES, THOUGH.

A two-toed sloth
Tim Evanson, Flickr // CC BY-SA 2.0

The names used to distinguish the sloths are somewhat of a misnomer. Both have three toes on each hind limb. The real difference applies to the fingers on their forelimbs; one family has two claws, while the other has three. To avoid confusion, some groups—like The Sloth Conservation Foundation—have starting calling them two-fingered and three-fingered sloths.

3. THEY'RE RELATED TO THE EXTINCT GIANT GROUND SLOTH.

Illustration of a giant sloth
iStock.com/estt

Two-toed and three-toed sloths both evolved from giant ground sloths, the largest of which weighed several tons and stood about 12 feet tall. The animals went extinct about 10,000 years ago, likely due to hunting by early humans.

4. THEY WOULD FAIL AN EYE EXAM.

Close-up of a sloth
iStock.com/BrianLasenby

Sloths aren't exactly known for their sharp senses, and this is especially true for their eyesight. A mama three-toed sloth can't spot her own baby from 5 feet away, and combative male sloths have been observed trying to hit each other from a similar distance. Scientists say a genetic mutation is to blame. Three-toed sloths are born without cone cells in their eyes, which are needed to detect colors. As a result, they see things in black and white, and in poorer resolution, too. They also have a hard time handling bright lights—not the best trait for a diurnal (daytime) creature to have.

5. THEY'RE SURPRISINGLY GOOD SWIMMERS.

Sloths are painfully sluggish on land. Their hind legs are weak, so they have to use their arms and upper body strength to pull themselves forward. Plop them in some water, though, and they can move three times as fast. Their long front arms make them skillful swimmers, and they can hold their breath underwater for up to 40 minutes. If a body of water is nearby, they may jump in and use it as a shortcut to navigate the forest more quickly. In the above clip narrated by David Attenborough, a male sloth swims as fast as he can—which is pretty fast, all things considered—to track down a female sloth's mating call.

6. THEIR "LAZINESS" IS A SURVIVAL TACTIC.

A sloth in a chair
iStock.com/GeorgePeters

It's no secret that sloths are slow. Their reaction time is about a quarter as fast as a human's, and they move at a pace of 6 to 8 feet per minute. Indeed, three-toed sloths are the slowest animals on Earth, beating out other famously slow animals like giant tortoises and snails. When the animals were first documented in 18th-century scientific texts, they were harshly described as "the lowest form of existence." But their slowness is why they haven't died out. Sloths largely subsist on leaves, and it can take up to a month for their four-part stomachs to digest a single meal. The leafy greens aren't very nutritious, so they have to conserve as much energy as possible to survive—and that means moving less. As a bonus, their slow movements help them go unnoticed by predators that rely on sight to hunt down prey, like jaguars, ocelots, and harpy eagles.

7. THEY DO JUST ABOUT EVERYTHING IN TREES …

A baby sloth hangs from a branch
iStock.com/Mark Kostich

Sloths are arboreal creatures, so they spend almost all of their time in trees. They eat, sleep, mate, and give birth while hanging upside-down—a feat made possible by their anatomy. Their internal organs are anchored to their abdomen, which shifts weight away from their diaphragm and lets them breathe more easily, and therefore expend less energy.

Three-inch claws also help them latch onto branches and stay suspended far above the forest floor. In fact, their innate ability to cling to branches is so strong that dead sloths have been found dangling from trees, lending new meaning to the phrase "death grip."

8. … EXCEPT POOP.

A sloth on the ground
iStock.com/Damocean

As a consequence of their slow metabolisms, sloths poop once a week—and sometimes just once a month. Two-toed sloths often let 'er rip from the trees, but three-toed sloths follow a bizarre routine that has baffled scientists. They typically make their way down to the forest floor to relieve their backed-up bowels, and once they get there, they do a little "poo dance" while digging a small hole to defecate inside. Without the camouflage afforded to them by the foliage of the forest canopy, sloths are much more likely to be picked off by predators. About half of all sloth fatalities occur when they're on the ground, most likely doing their business or finishing up. So why do they do it? It might have something to do with sex, and marking a tree for a potential mate to find. "Whatever is going on, it's got to be kind of life or death for survival," sloth biologist Rebecca Cliffe tells The Washington Post. "In my brain, that tells me that it's probably something to do with reproduction because that is the driving fact behind most animals' crazy behaviors."

9. AND THEIR POOPS ARE ENORMOUS.

A man holds a sloth
iStock.com/Ssviluppo

When they do poop, their turds tend to be massive. If you put the contents of a sloth's bowel movement on a scale, they might weigh up to one-third of the animal's body weight. This is 282 percent larger than what scientists would expect to see in an animal of the sloth's size. "You can watch their stomachs physically shrink as they poo," Cliffe tells The Washington Post. Oddly enough, though, sloths don't fart. So there's that.

10. ALGAE OFTEN GROWS ON THEIR FUR.

A sloth covered in algae
iStock.com/dene398

Sloths have a symbiotic relationship with algae. Studies have shown that algae is sometimes passed down from a mother sloth to her baby, and the transfer is mutually beneficial for both animal and plant. The sloth's long fur creates a cozy home for the algae—which readily absorbs the water they need to thrive—and the sloths get a coat of green-tinted fur that doubles as camouflage. Sloths also eat the algae, which provides a much-needed source of nutrients.

11. FEMALE SLOTHS SCREAM WHEN THEY WANT TO MATE.

Females get the courting process started by letting out a loud, high-pitched scream to let male sloths know she's ready to mate. "This call is a loud 'eeeeeh' lasting more or less one second," sloth researcher Adriano Chiarello tells Live Science. Researchers are unsure on the particulars of sloth courting or copulation, or even if males will fight for the right mate with the screeching female (or if any fights are territorial instead). Whatever the details, the ensuing gestation period is between five and six months, and then the female sloth will birth one baby sloth, which is—uninterestingly—just called a baby sloth.

12. THREE-TOED SLOTHS CAN ROTATE THEIR HEADS 270 DEGREES.

A sloth turns its head to look back
iStock.com/MikeLane45

This special talent puts three-toed sloths in the same category as many owls. In both species, this Exorcist-esque ability can be attributed to their bone structure. Sloths have extra vertebrae at the base of their necks that let them look in all directions with ease. Although sloths aren't great at defending themselves, they can at least see when danger is approaching.

13. FOR SUCH DEFENSELESS CREATURES, THEY LIVE FAIRLY LONG LIVES.

A sloth peeks out from behind a tree
iStock.com/Damocean

"Live slow, die whenever"—the unofficial slogan bestowed upon sloths by the internet—pretty much gets it right. On average, sloths live to be about 20 years old, but some species can live longer in captivity. The world's oldest sloth—a female of the Hoffman's two-toed variety named Miss C—died last year at the ripe old age of 43. She was a lifetime resident of Australia's Adelaide Zoo.

10 Rad Gifts for Hikers

Greg Rosenke/Unsplash
Greg Rosenke/Unsplash

The popularity of bird-watching, camping, and hiking has skyrocketed this year. Whether your gift recipients are weekend warriors or seasoned dirtbags, they'll appreciate these tools and gear for getting most out of their hiking experience.

1. Stanley Nesting Two-Cup Cookset; $14

Amazon

Stanley’s compact and lightweight cookset includes a 20-ounce stainless steel pot with a locking handle, a vented lid, and two insulated 10-ounce tumblers. It’s the perfect size for brewing hot coffee, rehydrating soup, or boiling water while out on the trail with a buddy. And as some hardcore backpackers note in their Amazon reviews, your favorite hiker can take the tumblers out and stuff the pot with a camp stove, matches, and other necessities to make good use of space in their pack.

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2. Osprey Sirrus and Stratos 24-Liter Hiking Packs; $140

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Osprey’s packs are designed with trail-tested details to maximize comfort and ease of use. The Sirrus pack (pictured) is sized for women, while the Stratos fits men’s proportions. Both include an internal sleeve for a hydration reservoir, exterior mesh and hipbelt pockets, an attachment for carrying trekking poles, and a built-in rain cover.

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3. Yeti Rambler 18-Ounce Bottle; $48

Amazon

Nothing beats ice-cold water after a summer hike or a sip of hot tea during a winter walk. The Yeti Rambler can serve up both: Beverages can stay hot or cold for hours thanks to its insulated construction, and its steel body (in a variety of colors) is basically indestructible. It will add weight to your hiker's pack, though—for a lighter-weight, non-insulated option, the tried-and-true Camelbak Chute water bottle is incredibly sturdy and leakproof.

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4. Mappinners Greatest 100 Hikes of the National Parks Scratch-Off Poster; $30

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The perfect gift for park baggers in your life (or yourself), this 16-inch-by-20-inch poster features epic hikes like Angel’s Landing in Zion National Park and Half Dome in Yosemite National Park. Once the hike is complete, you can scratch off the gold foil to reveal an illustration of the park.

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5. National Geographic Adventure Edition Road Atlas; $19

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Hikers can use this brand-new, updated road atlas to plan their next adventure. In addition to comprehensive maps of all 50 states, Puerto Rico, Canada, and Mexico, they'll get National Geographic’s top 100 outdoor destinations, useful details about the most popular national parks, and points on the maps noting off-the-beaten-path places to explore.  

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6. Adventure Medical Kits Hiker First-Aid Kit; $25

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This handy 67-piece kit is stuffed with all the things you hope your hiker will never need in the wilderness. Not only does it contain supplies for pain, cuts and scrapes, burns, and blisters (every hiker’s nemesis!), the items are organized clearly in the bag to make it easy to find tweezers or an alcohol wipe in an emergency.

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7. Hiker Hunger Ultralight Trekking Poles; $70

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Trekking poles will help increase your hiker's balance and stability and reduce strain on their lower body by distributing it to their arms and shoulders. This pair is made of carbon fiber, a super-strong and lightweight material. From the sweat-absorbing cork handles to the selection of pole tips for different terrain, these poles answer every need on the trail. 

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8. Leatherman Signal Camping Multitool; $120

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What can’t this multitool do? This gadget contains 19 hiking-friendly tools in a 4.5-inch package, including pliers, screwdrivers, bottle opener, saw, knife, hammer, wire cutter, and even an emergency whistle.

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9. RAVPower Power Bank; $24

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Don’t let your hiker get caught off the grid with a dead phone. They can charge RAVPower’s compact power bank before they head out on the trail, and then use it to quickly juice up a phone or tablet when the batteries get low. Its 3-inch-by-5-inch profile won’t take up much room in a pack or purse.

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10. Pack of Four Indestructible Field Books; $14

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Neither rain, nor snow, nor hail will be a match for these waterproof, tearproof 3.5-inch-by-5.5-inch notebooks. Your hiker can stick one in their pocket along with a regular pen or pencil to record details of their hike or brainstorm their next viral Tweet.

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10 Curious Facts About the Platypus

"Who are you calling a hoax?!"
"Who are you calling a hoax?!"
iStock/JohnCarnemolla

The platypus is arguably one of the most distinct animals on the planet. Here are a few things you might not have known about this quirky creature.

1. Platypuses don’t have stomachs.

Platypuses (platypodes and platypi are technically also correct, but much rarer in use) aren't the only animals to forgo an acid-producing part of the gut; spiny echidnas, and nearly a quarter of living fishes all have a gullet that connects directly to their intestines.

2. Platypus bills give them a “sixth sense.”

A platypus’s bill has thousands of cells that give it a sort of sixth sense, allowing them to detect the electric fields generated by all living things. It’s so sensitive that the platypus can hunt with its eyes, ears, and nose all closed, relying entirely on the bill’s electrolocation.

3. Platypuses used to be giant.

The ancient versions of a lot of modern animals, including penguins, were oversized monsters compared to the animals we know today—and platypuses are no different. In 2013, the discovery of a single tooth helped researchers identify a prehistoric platypus that was more than three feet long—double the size of the modern animal.

4. The platypus is a monotreme—which means “single hole” in Greek.

Platypuses are one of only five species of extant monotremes—just them and four species of echidna—which split from the rest of the mammals 166 million years ago. These egg-laying mammals get their name from the hole that serves as both an anus and a urino-genital opening. In 2008, scientists deciphered the entire DNA of the duck-billed platypus and determined that, in accordance with the animal’s somewhat bizarre appearance, the platypus shared genes with reptiles, birds, and mammals.

5. Platypuses nurse without nipples.

iStock

Although platypuses are born out of leathery eggs, the babies nurse from their mother. Female platypuses, however, don’t have nipples. Instead, their milk is released out of mammary gland ducts on their abdomen. The babies drink it up by sucking it out the folds of their mother's skin, or her fur.

6. Male platypuses have venomous spurs.

Platypuses are one of just a few venomous mammals, which is one of their more reptilian characteristics. But unlike snakes, a platypus’s venom isn’t in his teeth. Instead, males have a hollow spur on each hind leg from which venom is dispensed—but only sometimes. Although the spur itself is always there, the venom gland to which it is connected is seasonally-activated and only produces venom during mating season, indicating that its use is for fending off competing males.

7. Platypuses have retractable webbing.

Although they can only stay submerged in water for a few minutes—they are mammals, after all—platypuses are much better suited to scooting around in water than they are on land. Much like an otter, they prune their thick coat to add air bubbles that act as insulation in the cool rivers where they hunt. Out on land, the platypus's short limbs mean it has to exert 30 percent more energy than a similarly sized land-based mammal just to move around. All that said, they do have one particular adaptation to ease their terrestrial travel: The webbing between their front claws—a boon when paddling through streams—retracts when the platypus ambles up the riverbank to expose sharp claws.

8. Scientists thought the first known platypus was a hoax.

iStock

When the first platypus specimen was sent back to England from Australia in the late 18th century, the scientists who examined it thought that someone was playing a trick on them. "It naturally excites the idea of some deceptive preparation by artificial means," zoologist George Shaw wrote in the first scientific description of the platypus, published in 1799. One of the most remarkable and weird aspects of the platypus—its ability to lay eggs—wasn’t discovered for another 100 years.

9. Platypuses use gravel as makeshift teeth.

Platypuses don’t have teeth inside their bill, which makes it difficult to chew some of their favorite foods—but they have worked out a pretty ingenious solution. Along with worms, insects, shellfish, and whatever else these bottom-feeders scoop up to make a meal out of, the platypus also picks up gravel from the riverbed. The platypus packs it all into pouches in his cheek to carry it up to the surface where it munches away, using the bits of gravel as makeshift teeth to break up tougher food.

10. Platypuses use their tails for all sorts of things.

Unlike beavers, which have very visually similar tails, platypuses don't use their tails to slap the water in warning, or even to move them through the water. Most of the time, the primary function of the platypus's tail is just to store up to nearly half of the animal's body fat in case of a food shortage. A female platypus also uses her tail to hold incubating eggs against her warm body.