15 Delightful Facts About Dolphins

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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
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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
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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
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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
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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
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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.

Elderly Sloths Live Out Their Golden Years at a 'Retirement Home' in Wales Zoo

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iStock.com/TheDman

Where do sloths go when they retire from a cushy career of tree-dwelling and leaf-munching? To Wales, apparently. As The Atlanta Journal-Constitution reports, the Folly Farm in Pembrokeshire operates a retirement home for sloths of advanced age.

By removing older sloths from zoos and bringing them to the new facility in the southwest of Wales, space is freed up for younger sloths to mate. In turn, this helps conservation efforts, while also ensuring that older sloths get the love and care they deserve.

Much like human senior citizens, older sloths prefer to eat softer foods, such as boiled root vegetables. Their caretakers also ensure they get a regular dose of cod liver oil supplements to keep them healthy. The animals are still active, but with limited mobility. If they show any signs of struggling, staff might lower a tree's branches to make it easier for them to get down, according to zoo curator Tim Morphew.

Currently, the Folly Farm—which opened the retirement home last year—has two residents. Lightcap, a two-toed sloth, is one of the oldest sloths in Europe at 34 years old. Her roommate, Tuppee, is 10 years younger, but he’s also more cantankerous.

“Like many older men, Tuppee has been known to be a bit grumpy and even misbehaves at times but we know he’s a softie at heart,” Morphew told the BBC. “We’re hoping some older, female company will be a good influence on him and bring out the softer side of his nature. Sloths aren’t known for being social animals, but as they get older, we’ve found they do like company.”

Considering that sloths are pretty defenseless creatures, the animals live surprisingly long lives. Two-toed sloths live about 20 years in the wild, but can live more than 40 years in a zoo. In 2017, the world’s oldest sloth—a Hoffmann’s two-toed sloth named Miss C—died at an Australian zoo at the age of 43.

Morphew says the zoo may expand its sloth retirement home in the future.

[h/t The Atlanta Journal-Constitution]

These Custom-Made Slippers Are Designed to Look Exactly Like Your Pet

Cuddle Clones
Cuddle Clones

What gift do you get for the friend who’s completely obsessed with their cat or dog? Fluffy slippers that look just like their pet, of course. As Delish reports, Louisville, Kentucky-based company Cuddle Clones lets you upload photos of your pet and decide how you want them to appear—whether it’s in the form of a plush “clone” or furry footwear that you can sport around the house.

Many of the slippers are eerily lifelike and bear an uncanny resemblance to the animal they’re modeled after. “We do our very best to ensure that your Cuddle Clone captures the characteristics and likeness of your pet to the absolute best of our abilities,” the company writes on its website. “We are very proud of our products and how much they resemble the actual pets.”

A woman wears personalized dog slippers
Cuddle Clones

If customers aren’t completely satisfied with their order, Cuddle Clones offers a money-back guarantee. The process of ordering a pair of slippers is simple but takes some time. First, customers are prompted to enter their pet’s name and select its species—dog, cat, horse, and “other” are listed—as well as its breed.

From there, they will be asked to upload multiple photos of their pet’s face, chest, tail, fur color, and physique from various angles (including their right side, left side, and even their backside). They can then choose the eye color, list any distinguishing characteristics, and decide if they want the plush version of their pet to appear in any particular position.

The slippers, which are made in China, take eight weeks to make and ship to the U.S. However, customers can pay extra for expedited orders. They’re a bit pricey at $199, but then again, you’re paying for a handcrafted, personalized product.

Personalized cat slippers
Cuddle Clones

In addition to the “clones” and slippers, Cuddle Clones will also make personalized golf club covers, purses, and holiday stockings with your pet’s face on them. That way, you can take your fur baby with you anywhere, whether you’re on the golf course or out on the town.

[h/t Delish]

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