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.

A New DNA Test Will Break Down Your Cat's Breed

Basepaws
Basepaws

Modern DNA testing kits can reveal a lot of information about you just by sending your spit off to a lab for analysis. As a result, it's easier than ever to learn about your personal ancestry and health risks. And now, the same goes for your cat, too.

Basepaws is now offering what it calls the "world's first DNA test for cats," which can tell you which breeds your beloved fur baby likely descended from, in addition to other information about their characteristics. The CatKit will reveal whether your little Simba is more similar to an American Shorthair, Abyssinian, or one of the other 30 breeds on record, as well as determining which of the "big cats" (think lions) your kitty has the most in common with.

Here's how it works: After receiving your kit in the mail, you will be asked to collect a DNA sample from your feline friend. The current kit includes adhesives for collecting cat hair, but Basepaws will soon roll out new kits that call for saliva samples instead. (This will provide a more consistent DNA sample, while also allowing staff to process more samples at once, according to a company spokesperson. It also will make it easier to collect samples from hairless cats like Sphinxes.)

A cat DNA test result
Basepaws

Once you collect the sample, just mail it in and wait eight to 12 weeks for your report. Basepaws uses sequencing machines to "read" your kitty's genetic code, comparing it to the sequences of other cats in its network. "More than 99 percent of your cat's genetic sequence will be similar to every other cat; it's the small differences that make your cat unique," Basepaws writes on its website.

In the future, Basepaws will also be able to determine your cat's predisposition for certain diseases, as well as their personality and physical traits. The company holds on to your cat's genetic data, allowing it to provide updates about your cat as the Basepaws database continues to grow.

Order a kit on the Basepaws website for $95. Enter the code "MEOWRCH-I5W3RH" at the checkout for a 10 percent discount.

And don't feel left out if you're a dog lover rather than a cat person—Wisdom Panel offers a similar service for canine companions. Its kit is available for $73 on Amazon.

A Nubian Goat Named Lincoln Was Just Sworn in as the Mayor of Fair Haven, Vermont

iStock.com/Evgeniia Khmelnitskaia
iStock.com/Evgeniia Khmelnitskaia

Lincoln the goat may not be housebroken, but she had no problem winning the race for mayor of Fair Haven, Vermont. The new mayor was officially sworn in on Tuesday, March 12, and before signing the oath of office with her hoof print, she marked the occasion by defecating on the town hall floor, the Boston Globe reports.

Prior to getting into politics, Lincoln the droopy-eared Nubian goat lived a simple life. A local family looking for a way to maintain the unruly vegetation on their property had purchased her two years ago when she was 1 year old. At age 3, Lincoln transitioned from munching grass full-time to running for public office.

Though Lincoln's win is impressive, her election didn't involve beating any human candidates. Town Manager Joseph Gunter came up with the idea to hold an election for honorary pet mayor of Fair Haven as way to raise money for a new playground. For a $5 fee, local kids were allowed to nominate the pet of their choice to be town mayor. Lincoln bested more than a dozen candidates, including a gerbil named Crystal and a pacifier-sucking dog named Stella, for the position.

The stunt didn't raise much money—the town came away with just $100 for the playground—but it did earn Fair Haven international attention. In order to go down in history as world's longest-serving animal mayor, Lincoln has to stick around for a while; Stubbs the cat was mayor of Talkeetna, Alaska for 20 years.

[h/t Boston Globe]

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