iStock
iStock

10 Trippy Facts About Triops

iStock
iStock

Try to picture a tiny, transparent crustacean that looks like a hybrid of a centipede and a horseshoe crab with a zillion writhing legs. While they’re not likely to win any beauty contests, triops are impressive little critters. The genus Triops has been around for as long as 300 million years—that’s about 200 million years older than T. Rex—making them the oldest known animals on the planet. Here are some other fun facts about these resilient creatures.

1. TRIOPS ARE OFTEN CALLED "LIVING FOSSILS,” BUT THAT'S A MISNOMER.

Commonly known as tadpole shrimp, they appear to be almost identical physically to their fossilized ancestors. But appearances can be deceiving. Recent research shows that their DNA and reproductive techniques are constantly evolving.

2. THEY OFTEN HAVE A VARIETY OF WAYS TO REPRODUCE.

In addition to sexual reproduction, some eggs are capable of developing without fertilization. Other triops are hermaphrodites. This means an entire population can develop from just one egg. No wonder they’ve survived for so long.

3. THERE ARE MORE THAN A DOZEN TRIOPS SPECIES.

Wikimedia Commons // CC BY-SA 3.0 

They're found in seasonal ponds, pools, and puddles all over the world. Triops were around before the break-up of the last supercontinent, which helps explain why they live on every continent except Antarctica. Triops longicaudatus, a rather fancy critter with a long tail, frequents all but the colder regions of North America, while Triops newberryi prefers the milder climate of the Pacific Northwest and parts of California. Triops granarius is found throughout much of Africa, the Middle East, and parts of Asia. Triops Australiensis calls, you guessed it, Australia home. Triops cancriformis, the oldest species, hails from Europe, the Middle East, and India, and is considered endangered in the UK.  

4. TRIOPS MEANS "THREE EYES" IN GREEK.

They Might Be Giants wrote a song about this helpful feature. Sing along with the kids:

Two eyes on a face
Are usually enough
But triops has got
One that looks up
And one that looks around
And one to keep an eye
On the other pair of guys
Triops has three eyes

5. THEY CAN HAVE AS MANY AS 140 (SURPRISINGLY MULTIPURPOSE) LEGS.

What what they do with them is far more impressive than walking or swimming. Some legs act as antennae that help them find food, while others create a water current to direct food toward their mouth. Females have capsules on some of their legs to carry eggs. Some triops have lobe or leaf-like extensions on their legs that function similarly to gills, allowing them to breathe.

6.THEY EAT A LOT—INCLUDING EACH OTHER.

iStock

Triops have a varied diet, from mosquito larvae to aquatic plants and tiny invertebrates to, um, other triops. Yes, to support their rapid growth, larger triops will cannibalize smaller ones if food supplies run low. Hey, when your home is perpetually in danger of drying up, you have to eat as much as you can so you can grow and breed before it’s too late.

7. THEY GROW QUICKLY—AND THAT CAN BE DEADLY.

Many reaching maturity in one to two weeks—but their exoskeletons do not. That requires them to molt regularly as they outgrow their exoskeletons. Young triops grow so quickly that molting is a daily experience, and a dangerous one: They can die if they don’t successfully shed the old exoskeleton.

8. TRIOPS EGGS CAN LAY DORMANT FOR DECADES, AND THEN HATCH IN WATER.

Wikimedia Commons // Public Domain

They achieve this by laying something called cysts, or resting eggs, that are eggs with a special structure that protects the interior from extreme temperatures, drought, and even radiation. These cysts allow triops to move into new territory by hitching a ride with some pretty far-out modes of transportation, including inside migrating birds and in the feet and poop of animals that pick them up from puddles and pools.

9. THEY CAN SURVIVE IN OUTER SPACE FOR 18 MONTHS.

Tests on the International Space Station (ISS) prove this hardiness. Those findings led to a NASA high school experiment last year that sent Triops Longicaudatus back to the ISS to test whether it could be grown in space and serve as a high-protein food source for astronauts on future long-term missions.

10. CHARMED? YOU CAN HAVE YOUR OWN!

There is a wide assortment of triops starter kits out there to choose from. They’re low-commitment, too: Triops only live for 1–3 months (less if they eat each other). And when one batch dies out, you can dry out the soil or sand in the tank and transfer it to fresh water. If resting eggs are in the sand, with the proper care, you'll soon have another group of triops. 

nextArticle.image_alt|e
iStock
arrow
Animals
14 Bold Facts About Bald Eagles
iStock
iStock

Bald eagles are powerful symbols of America—but there’s a whole lot more to these quirky birds.

1. YOUNG BALD EAGLES AREN'T BALD.

A young bald eagle with a brown head on a beach.
iStock

So obviously adult bald eagles aren't really bald, either—their heads have bright white plumage that contrasts with their dark body feathers, giving them a "bald" look. But young bald eagles have mostly brown heads. In fact, for the first four or five years of their lives, they move through a complicated series of different plumage patterns; in their second year, for instance, they have white bellies.

2. BALD EAGLES SOUND SO SILLY THAT HOLLYWOOD DUBS OVER THEIR VOICES.

A red-tailed hawk.
A red-tailed hawk's screech is usually dubbed over the bald eagle's weaker scream.
iStock

It's a scene you’ve probably seen countless times in movies and on TV: an eagle flies overhead and emits a rough, piercing scream. It's a classic symbol of wilderness and adventure. The only problem? Bald eagles don't make that sound.

Instead, they emit a sort of high-pitched giggle or a weak scream. These noises are so unimpressive that Hollywood sound editors often dub over bald eagle calls with far more impressive sounds: the piercing, earthy screams of a smaller bird, the red-tailed hawk. If you were a fan of The Colbert Report, you might remember the show's iconic CGI eagle from the opener—it, too, is making that red-tailed hawk cry. Listen for yourself and decide who sounds more impressive.

3. THEY EAT TRASH AND STOLEN FOOD.

Two bald eagles guard their prey against two magpies on a snowy field.
iStock

Picture a majestic bald eagle swooping low over a lake and catching a fish in its powerful claws. Yes, bald eagles eat a lot of fish—but they don't always catch it themselves. They've perfected the art of stealing fish from other birds such as ospreys, chasing them down until they drop their prey.

Bald eagles will also snack on gulls, ducks, rabbits, crabs, amphibians, and more. They'll scavenge in dumpsters, feed on waste from fish processing plants, and even gorge on carrion (dead, decaying animals).

4. BALD EAGLES USUALLY MATE FOR LIFE.

Two bald eagles perched on a tree.
iStock

Trash and carrion aside, they're pretty romantic animals. Bald eagles tend to pair up for life, and they share parenting duties: the male and the female take turns incubating the eggs, and they both feed their young.

5. … AND THEY LIVE PRETTY LONG LIVES.

Two bald eagles sitting on a rock.
iStock

Those romantic partnerships are even more impressive because bald eagles can survive for decades. In 2015, a wild eagle in Henrietta, New York, died at the record age of 38. Considering that these birds pair up at 4 or 5 years of age, that's a lot of Valentine's Days.

6. THEY HOLD THE RECORD FOR THE LARGEST BIRD'S NEST.

Two bald eagles in their large nest.
iStock

Bald eagles build enormous nests high in the treetops. The male and female work on the nest together, and this quality time helps them cement their lifelong bond. Their cozy nurseries consist of a framework of sticks lined with softer stuff such as grass and feathers. If the nest serves them well during the breeding season, they'll keep using it year after year. And, like all homeowners, they can't resist the thought of renovating and adding to their abode. Every year, they'll spruce it up with a whopping foot or two of new material.

On average, bald eagle nests are 2-4 feet deep and 4-5 feet wide. But one pair of eagles near St. Petersburg, Florida, earned the Guinness World Record for largest bird’s nest: 20 feet deep and 9.5 feet wide. The nest weighed over two tons.

7. FEMALES ARE LARGER THAN MALES.

Two bald eagles in their large nest.
iStock

In many animal species, males are (on average) larger than females. Male gorillas, for example, dwarf their female counterparts. But for most birds of prey, it's the opposite. Male bald eagles weight about 25 percent less than females.

Scientists aren't sure why there's such a size difference. One reason might be the way they divide up their nesting duties. Females take the lead in arranging the nesting material, so being bigger might help them take charge. Also, they spend longer incubating the eggs than males, so their size could intimidate would-be egg thieves.

If you're trying to tell male and female eagles apart, this size difference may help you—especially since both sexes have the same plumage patterns.

8. TO IDENTIFY THEM, LOOK AT THE WINGS.

A bald eagle flies across the water.
iStock

People often get excited about a big soaring bird and yell "It's an eagle!” just before it swoops closer and … oops, it's a vulture. Here's a handy identification tip. Bald eagles usually soar with their wings almost flat. On the other hand, the turkey vulture—another dark, soaring bird—holds its wings up in a shallow V shape called a dihedral. A lot of large hawks also soar with slightly raised wings.

9. THEY'RE COMEBACK KIDS.

Baby eagle chicks in a nest.
iStock

Before European settlers arrived, bald eagles were abundant across the U.S. But with settlement came habitat destruction, and the settlers viewed the eagles as competition for game and as a threat to livestock. So many eagles were killed that in 1940 Congress passed an act to protect the birds.

Unfortunately, another threat rose up at about that time. Starting after World War II, farmers and public health officials used an insecticide called DDT. The chemical worked well to eradicate mosquitos and agricultural pests—but as it traveled up the food chain, it began to heavily affect birds of prey. DDT made eagle eggshells too thin and caused the eggs to break. A 1963 survey found just 471 bald eagle pairs in the lower 48 states.

DDT was banned in the early 1970s, and conservationists began to breed bald eagles in captivity and reintroduce them in places across America. Luckily, this species made a spectacular recovery. Now the lower 48 states boast over 9700 nesting pairs.

10. THEY'RE UNIQUELY NORTH AMERICAN.

An African fish eagle flies over the water.
The African fish eagle is a relative of the North American bald eagle.
iStock

You've probably heard of America's other eagle: the golden eagle. This bird lives throughout much of the northern hemisphere. But the bald eagle is only found in North America. It lives across much of Canada and the U.S., as well as northern parts of Mexico.

Though it may be North American, the bald eagle has seven close relatives that are found throughout the world. They all belong to the genus Haliaeetus, which comes—pretty unimaginatively—from the Latin words for "sea" and "eagle." One relative, the African fish eagle, is a powerful symbol in its own right. It represents several countries; for example, it's the national symbol of Zambia, and graces the South Sudanese, Malawian, and Namibian coats of arms.

11. THEY'RE AERIAL DAREDEVILS.

A bald eagle carries a fish off in its talons.
iStock

It seems too weird to be true: While flying, bald eagles sometimes grab each other's feet and spin while plummeting to the Earth. Scientists aren't sure why they do this—perhaps it's a courtship ritual or a territorial battle. Usually, the pair will separate before hitting the ground (as seen in this remarkable set of photographs). But sometimes they hold tight and don't let go. These two male bald eagles locked talons and hit the ground with their feet still connected. One subsequently escaped and the other was treated for talon wounds.

12. THEIR EYES ARE AMAZING.

Close-up of a bald eagle's face.
iStock

What if you could close your eyes and still see? Besides the usual pair of eyelids, bald eagles have a see-through eyelid called a nictitating membrane. They can close this membrane to protect their eyes while their main eyelids remain open. The membrane also helps moisten and clean their eyes.

Eagles also have sharper vision than people, and their field of vision is wider. Plus, they can see ultraviolet light. Both of those things mean the expression "eagle eye" is spot-on.

13. THEY MIGRATE … SORT OF.

A bald eagle sits in a snowy tree.
iStock

If you're a bald eagle that nests in northern Canada, you'll probably head south for the winter to avoid the punishing cold. Many eagles fly south for the winter and return north for the summer—as do plenty of other bird species (and retired Canadians). But not all bald eagles migrate. Some of them, including individuals in New England and Canada's Maritime provinces, stick around all year. Whether or not a bird migrates depends on how old it is and how much food is available.

14. THEY CAN SWIM … SORT OF.

A bald eagle
iStock

There are several videos online—like the one above—that show a bald eagle swimming in the sea, rowing itself to shore with its huge wings. Eagles have hollow bones and fluffy down, so they can float pretty well. But why swim instead of soar? Sometimes, an eagle will swoop down and grab an especially weighty fish, then paddle it to shore to eat.

Note that the announcer in the video above says that the eagle's talons are "locked" on a fish that's too heavy to carry. In fact, those lockable talons are an urban legend.

nextArticle.image_alt|e
iStock
arrow
Animals
How Bats Protect Rare Books at This Portuguese Library
iStock
iStock

Visit the Joanina Library at the University of Coimbra in Portugal at night and you might think the building has a bat problem. It's true that common pipistrelle bats live there, occupying the space behind the bookshelves by day and swooping beneath the arched ceilings and in and out of windows once the sun goes down, but they're not a problem. As Smithsonian reports, the bats play a vital role in preserving the institution's manuscripts, so librarians are in no hurry to get rid of them.

The bats that live in the library don't damage the books and, because they're nocturnal, they usually don't bother the human guests. The much bigger danger to the collection is the insect population. Many bug species are known to gnaw on paper, which could be disastrous for the library's rare items that date from before the 19th century. The bats act as a natural form of pest control: At night, they feast on the insects that would otherwise feast on library books.

The Joanina Library is famous for being one of the most architecturally stunning libraries on earth. It was constructed before 1725, but when exactly the bats arrived is unknown. Librarians can say for sure they've been flapping around the halls since at least the 1800s.

Though bats have no reason to go after the materials, there is one threat they pose to the interior: falling feces. Librarians protect against this by covering their 18th-century tables with fabric made from animal skin at night and cleaning the floors of guano every morning.

[h/t Smithsonian]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios