15 Delightful Facts About Dolphins

iStock
iStock

Dolphins are known for being smart, playful creatures that can learn to perform impressive tricks. But you might not know that dolphins are also champion nappers who have helped the U.S. Navy protect nuclear warheads. We're celebrating National Dolphin Day with these 15 facts about the cute, friendly cetaceans.

1. THEY'RE EXCELLENT NAPPERS.

Since dolphins can't breathe underwater, they need to swim up to the ocean's surface to get air. So how do they sleep without drowning? Essentially, dolphins are champion power nappers. Rather than sleep for several hours at a time, they rest one hemisphere of their brain for 15 to 20 minutes at a time, and they take these "naps" several times each day. By resting one hemisphere of their brain at a time, dolphins can continue swimming, breathing, and watching for predators 24/7.

2. THEY COMMUNICATE WITH CLICKS AND WHISTLES …

dolphins underwater
iStock

Dolphins communicate with one another underwater by making a variety of vocalizations. To find prey and navigate the ocean, they make clicking sounds, and they "speak" to other dolphins by whistling. Dolphins also produce loud burst-pulse sounds when they feel excited or aggressive, such as when they need to scare off a nearby shark. Some female dolphins also produce a burst-pulse to reprimand their offspring, called calves, for bad behavior.

3. … BUT THEIR LANGUAGE REMAINS A MYSTERY.

Although marine scientists have studied and recorded dolphin vocalizations for decades, many aspects of the animals’ language and how they communicate are still unknown. Scientists have not yet broken down the individual units of dolphin sounds, and they're still searching for a Rosetta Stone that links the animals' vocalizations to their behavior. By using new technologies—including algorithms and high-frequency recorders that work underwater—scientists hope to finally unlock the mystery of the dolphin language.

4. THEY USE ECHOLOCATION TO NAVIGATE.

To know where they are in relation to other objects and animals, dolphins use echolocation (a.k.a. biological sonar). After emitting a series of high-pitched clicks, they listen for the echoes to bounce off their surroundings. Based on these echoes, dolphins can judge where they are in space and determine the size and shape of nearby objects. Besides helping dolphins evade predators, echolocation allows them to trap, catch, and eat fish and squid.

5. THEY MAKE FRIENDS WITH OTHER DOLPHINS …

spotted dolphins swimming
iStock

Dolphins are highly social, and scientists are still discovering fascinating details about how the aquatic mammals socialize with one another. In 2015, scientists at Florida Atlantic University's Harbor Branch Oceanographic Institute published research in the Marine Mammal Science journal about the social networks of dolphins. After spending over six years tracking 200 bottlenose dolphins in Florida's Indian River Lagoon, the scientists discovered that dolphins have friends. Instead of spending equal time with the dolphins around them, the animals actually segregate themselves into friend groups. Just like humans, dolphins seem to prefer the company of certain peers more than others.

6. … AND EACH DOLPHIN RESPONDS TO ITS OWN NAME.

Dolphins aren't swimming around with name tags, but every dolphin has its own unique whistle. Scientists believe that dolphins use these signature whistles for life, and female dolphins may even teach their calves their whistles before they're born. Dolphins use their signature whistles to call out to one another and may be able to remember other dolphins' whistles after decades apart.

7. THERE ARE 44 DIFFERENT DOLPHIN SPECIES.

an orca jumping out of the water
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Although bottlenose dolphins are the most well-known and recognizable, there are 43 other dolphin species. Most species live in temperate and tropical oceans, but a few live in colder oceans or rivers. Depending on their species, dolphins can vary considerably in their physical attributes and behavior. For example, the largest dolphin species, the Orca (also called Killer Whale), can be 30 feet long—10 times longer than the smallest dolphins.

8. THEY DON'T USE THEIR TEETH TO CHEW FOOD.

two smiling dolphins
iStock

Dolphins have teeth, but they don't use their chompers to chew food. Instead, dolphins use their teeth to catch prey (fish, crustaceans, and squid) and swallow it whole. Since they forgo chewing, digestion occurs in their stomach—or, more precisely, in part of their stomach. Dolphins have multiple stomach chambers, one of which is devoted to digestion, while the other chambers store food before it's digested.

9. THEY TYPICALLY GIVE BIRTH TO JUST ONE CALF.

mother and baby dolphin
iStock

Depending on their species, most female dolphins (called cows) carry their babies for nine to 17 months before giving birth to a calf. Interestingly, calves are born tail first, rather than head first, so they don't drown during the birthing process. After nursing for one to two years, a calf typically stays with its mother for the next one to seven years, before mating and having its own calves.

10. THEIR SKIN CAN BE REGENERATED EVERY TWO HOURS.

If you've ever swum with dolphins, you know their skin looks and feels super smooth and sleek. There's a reason for that—a dolphin's epidermis (outer layer of skin) can be sloughed off and replaced with new skin cells as often as every two hours. Because their skin regenerates so often, it stays smooth and, as most scientists believe, reduces drag as they swim.

11. THE U.S. NAVY TRAINS DOLPHINS TO PROTECT NUCLEAR WEAPONS.

A bottlenose dolphin named K-Dog from the Commander Task Unit jumps out of the water in 2003. Commander Task Unit is comprised of special mine clearing teams from The United Kingdom, Australia, and the U.S.
A bottlenose dolphin named K-Dog from the Commander Task Unit jumps out of the water in 2003. Commander Task Unit is comprised of special mine clearing teams from The United Kingdom, Australia, and the U.S.
Brien Aho, U.S. Navy/Getty Images

Despite dolphins' general friendliness, some of them are trained for combat. The Navy Marine Mammal Program at San Diego's Space and Naval Warfare Systems Command (SPAWAR) trains dozens of bottlenose dolphins (as well as sea lions) to help the U.S. Navy. In the past, the U.S. military has used dolphins in conflicts in Vietnam and the Persian Gulf. Today, thanks to their intelligence, speed, and echolocation skills, dolphins are trained to find enemy swimmers, locate underwater mines, and guard nuclear arsenals.

12. THEY'RE NOT THE SAME AS PORPOISES.

To the untrained eye, dolphins and porpoises look nearly identical, and many people mistakenly think that porpoises are a type of dolphin. But the two species belong to completely different families and differ in their physical attributes. So how can you tell them apart? Dolphins, which are usually bigger than porpoises, typically have longer beaks and curved dorsal fins. Porpoises, on the other hand, have more triangular dorsal fins as well as spade-shaped (rather than conical) teeth.

13. HUNTING, OVERFISHING, AND RISING OCEAN TEMPERATURES THREATEN THEM.

Some dolphin species are endangered or functionally extinct (like China's baiji dolphin) due to hunting, overfishing, and pollution. Although dolphin meat is high in mercury, the animals are still hunted for their meat and eaten in parts of Japan and the Faroe Islands of Denmark. Overfishing means that dolphins' food sources are shrinking, and some dolphins get caught up in fishing nets and die. Additionally, climate change and rising ocean temperatures are driving some fish and squid away from their natural habitats, putting dolphins' main food source at risk.

14. A SUPERPOD CAN CONSIST OF MORE THAN 1000 DOLPHINS.

a pod of dolphins swimming
iStock

Dolphins live in groups, called pods, that typically contain dozens or hundreds of dolphins. By swimming in a pod, dolphins work together to hunt prey, evade predators, and care for sick or injured members. But different pods can also merge, forming a superpod of more than 1000 dolphins. Superpods are typically temporary and occur in parts of the ocean with plentiful food (and less competition for tasty squid).

15. THE OLDEST DOLPHIN IN CAPTIVITY LIVED TO 61 YEARS OLD.

Dolphin lifespan varies greatly by species. Most dolphins in the wild live for a few decades, while those in captivity have a drastically reduced lifespan and may live for only a few years. So it's all the more shocking that the oldest dolphin in captivity lived to be a sexagenarian. Nellie, a bottlenose dolphin who lived in a marine entertainment park in Florida, was born in 1953. She appeared on TV shows and commercials and performed tricks for the park's attendees before passing away in 2014.

‘Soft and Cuddly’ Venomous Puss Caterpillars Have Been Spotted in at Least 3 States

Wayne W G, Flickr // CC BY-NC 2.0
Wayne W G, Flickr // CC BY-NC 2.0

The puss caterpillar is cute, cuddly, and coming to ruin your day.

USA Today reports that the highly venomous creature, also known as the southern flannel moth caterpillar, or asp, has recently been spotted in Florida, Texas, and South Carolina. Underneath its furry coat are tiny, potent spines that break off and attach themselves to your skin, causing excruciating pain and creating a hematoma, a bruise-like wound under your skin where blood has leaked from blood vessels.

According to University of Connecticut entomologist David Wagner, the caterpillar is dangerous partly because the sting of those spines becomes more painful over time. “It builds for a long time in a frightening way. No one expects stings to gain in impact or discomfort, and these will,” he told USA Today. “It packs quite a wallop.”

For one victim in Dade City, Florida, even medically administered morphine didn’t alleviate her agony. “It felt like someone was drilling into my bones,” she wrote in a Facebook post. “I cried and pleaded with God for hours to make it stop.”

puss caterpillar
going on going on, Flickr // CC BY-NC 2.0

If one does happen to inch its way onto you, curb the instinct to flail about or swat at random—trying to brush off the adorable nightmare just increases the possibility of those sinister spines sticking to your skin. Instead, have someone carefully and calmly remove the insect with a twig or a 39-and-a-half-foot pole. Then, take a shower and wash your clothes to minimize further exposure to leftover spines.

As traumatizing as the experience sounds, your chances of meeting one of these fun-sized villains are hearteningly slim. Wagner explains that they’re particularly scarce above the Mason-Dixon line, and not even very common in southern states, where they’re usually spotted.

In short, this is just another scientific reason why you should stick to petting dogs.

[h/t USA Today]

8 Adorable Products You Can Buy for International Sloth Day

Good Luck Socks/Intelex via Amazon
Good Luck Socks/Intelex via Amazon

It’s that time of the year again, folks—the time when we all collectively lose our chill over a slow-moving, two- or three-toed mammal with an adorable squeak and poop that defies physics. That’s right: International Sloth Day is coming on October 20. Here’s a list of must-have coloring books, onesies, and Christmas sweaters that you can pick up to showcase your love of one of the internet's favorite animals.

1. Cuddly Microwaveable Sloth; $23

Microwavable sloth for International Sloth Day.
Intelex/Amazon

Warm your heart and your body with a plush sloth that doubles as a soothing heating pad. The toy is filled with millet grains and dried French lavender, a combination intended to help you get to sleep easier.

Buy it: Amazon

2. Hanging Ceramic Sloth Planter; $19

FattyBee Ceramic Sloth Planter.
FattyBee/Amazon

This flower planter pulls double duty, communicating both your love of sloths and your appreciation for plants. And it makes a tasteful piece of hanging home decor, too.

Buy it: Amazon

3. Sloth Coloring Book; $7

Sloth Coloring Book on Amazon.
CreateSpace Independent Publishing Platform/Amazon

Sloths themselves are already works of art, but you’d be forgiven for wanting a few more sloth-related crafts in your life. Now you can make your own masterpiece with this detailed coloring book. All you'll need are some colored pencils and you'll be ready to go.

Buy it: Amazon

4. Farting Sloth Coloring Book; $7

Sloth Farts Coloring Book on Amazon.
M & L Coloring Books/Amazon

But maybe traditional coloring books aren’t your thing. You’re in luck: Amazon sells a coloring book for the crowd that both loves sloths and laughs a little too much at farts.

Buy it: Amazon

5. Sloth Socks; $14

Sloth Socks on Amazon.
Good Luck Socks/Amazon

These socks are ideal for people who might not want to wear their love of sloths out in the open but are very comfortable showing it off on their ankles.

Buy it: Amazon

6. Sloth Onesie; $60

Tipsy Elves Sloth Onesie on Amazon.
Tipsy Elves/Amazon

No list of sloth-related products would be complete without a cozy onesie, and this one from Tipsy Elves is perfect for either pajamas or a last-minute Halloween costume. This onesie even comes with zippered pockets and cuddly sloth claws!

Buy it: Amazon

7. Sloth-Themed Ugly Christmas Sweater; $45


Tipsy Elves/Amazon

Why not celebrate the upcoming holiday season with this sloth-themed ugly Christmas sweater? You’re sure to be the hit of any holiday pub crawl or office Christmas party.

Buy it: Amazon

8. Sloth Mug; $13


Mika Mugs/Amazon

Really, what says it better than this mug? You just really freaking love sloths, and there’s nothing wrong with that, so be sure to declare your feelings along with your morning cup of coffee.

Buy it: Amazon

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