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10 Terrific Facts About Trilobites

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iStock

For nearly 300 million years, these ancient mariners dotted our ocean floors—surviving, thriving, and fossilizing beneath the waves.

1. OVER 20,000 SPECIES ARE CURRENTLY KNOWN.

Every single continent has yielded trilobite remains. The biggest species (Isotelus rex) was some 28 inches long, while the smallest measured less than a millimeter from end to end. Some sported defensive spines, while others had smooth, rounded shells. And whereas certain trilobites came with disproportionately large eyes, many deep-sea species were blind.

2. TRILOBITES FIRST APPEARED AROUND 540 MILLION YEARS AGO.

Their debut roughly coincided with the dawn of the Cambrian period. During this game-changing chapter in Earth’s history, multi-celled organisms went through an apparent explosion in diversity, or at least an explosion in life forms that leave fossils. New creatures—including a barrage of mollusks and arthropods—seem to have evolved at an unprecedented rate.

The Cambrian also saw trilobites become the most common and diverse animals on the planet. However, trilobites began to decline when the period ended some 500 million years ago. Though the invertebrates stuck around for another 240 million years, they’d never again be so successful.

3. MANY WOULD CURL UP INTO LITTLE BALLS FOR PROTECTION.

When danger struck, some trilobites could ball themselves up like underwater pill bugs, with their rear end flexed under their head. Specimens dating as far back as the late Cambrian have been found in this defensive position. 

4. AT FIRST, SCIENTISTS DIDN’T KNOW WHAT TO MAKE OF THEM.

Fæ, Wikimedia // Public domain

In a 1679 letter, Welsh linguist and naturalist Edward Lhuyd misidentified one as “the sceleton [sic] of some Flat-fish.” Bishop Charles Lyttleton came a little closer to the mark in 1750 when he wrote London’s Royal Society about a “petrified Ins[e]ct” that he’d dug up a year before. While trilobites were, in fact, arthropods, the creatures appear to have been more closely akin to crustaceans and/or chelicerates (i.e. arachnids and horseshoe crabs) than insects.

5. MOST TRILOBITE FOSSILS ARE ACTUALLY MOLTED EXOSKELETONS.

ellenm1,Wikimedia // CC BY 2.0

Over the course of its life, a trilobite outgrew many shells. During the molting process, these discarded husks would often get preserved for posterity. One trilobite could therefore leave behind several trilobite-shaped fossils. Specimens that represent the actual creature—as opposed to its shuffled-off shell—are comparatively rare

6. THREE STATES HAVE MADE A TRILOBITE THEIR OFFICIAL FOSSIL.

JMCC1, Wikimedia // CC BY-SA 3.0 

In 1985, Ohio chose the entire Isotelus genus and Wisconsin went with Calymene celebra. Three years later, Pennsylvania picked Phacops rana after an elementary school class lobbied for its appointment.

 7. TRILOBITES GATHERED FOOD IN A VARIETY OF WAYS.

Generally speaking, early trilobites seem to have hunted down aquatic worms and eaten them alive. It’s been theorized that a few other species evolved to eat plankton or algae—with some making use of a filter-feeding mechanism.

8. TRILOBITES WERE WIPED OUT BY THE BIGGEST EXTINCTION IN HISTORY.

NASA/JPL-Caltech/UCLA (WISE),Wikimedia Commons

Some call it the "Great Dying”—250 million years ago, 90 percent of all species on earth suddenly perished. Possible causes include everything from increased volcanic activity to exploding supernovas. Regardless, the event—also known as the Permian Extinction—killed off a number of insects, sharks, armored fish, mammal-like creatures, and countless other organisms. Trilobites, however, are by far the most famous lineage to have met their end this way.  

9. NATIVE AMERICANS USED THEM AS AMULETS.

Long before Europeans first set foot on the continent, the Pahvant Ute people, from what is now called Utah, gathered Cambrian trilobites. Believing that the fossils harbored special powers, the natives carried them around as protective charms. These odd, petrified critters were given the name “Timpe-Konitza-Pachuee,” or “little water bug living in a house of stone.”

10. ONE CHINESE TRILOBITE WAS NAMED AFTER A STAR WARS CHARACTER.

Dwergenpaartje, Wikimedia // CC BY-SA 3.0

Around the start of the last decade, paleontologist Samuel Turvey happened upon several new species of trilobites while exploring in China. He gave one new invertebrate the genus name Han, which it shares with China’s biggest ethnic group. When the time came to pick species names, Turvey couldn’t resist bolstering his Star Wars cred, and named one particular trilobite Han solo. (It helped that Han solo was the only species in the genus.)

All photos courtesy of iStock unless otherwise noted. 

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IKEA
IKEA Is Recalling Its New Dog Water Fountain Due to Suffocation Risk
IKEA
IKEA

In late 2017, IKEA released LURVIG, its first-ever line for pets, a collection that included beds, leashes, food bowls, and other staple products for dogs and cats. Unfortunately, one of those products is now being recalled over safety issues, according to Fast Company. If you own the LURVIG water dispenser, you should take it away from your pet immediately.

The automatic water fountain poses a suffocation hazard, the company announced in a recent statement. The retailer has received two reports of pets dying after getting their head stuck in it.

A water fountain for pets sits next to a bowl full of dog food.
IKEA

The $8 water dispenser debuted in U.S. stores in October 2017 with the rest of its LURVIG line. Awkwardly enough, the product description included assurances of the product’s safety standards. It explained that “the LURVIG range was developed with the assistance of trained veterinarian Dr. Barbara Schäfer, who also works with product risk assessment at IKEA,” and went on to say that “the first thing to consider was safety: ‘Dogs will definitely chew on their toys and bring in dirt from their daily walks. Cats will definitely scratch on most surfaces and are sensitive to smell and texture. So safe, durable materials are very important.’”

It seems that smaller dogs are able to get their faces stuck in the dome-shaped plastic reservoir, which only appears to have one hole in it, at the bottom. As a result, dogs can suffocate if they can’t get out of it.

The product has been removed from IKEA’s website, and the retailer recommends that anyone who bought it stop using it and return it to the nearest IKEA store for a refund.

[h/t Fast Company]

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Alamy
10 Facts About the Portuguese Man O' War
Alamy
Alamy

Something a lot scarier than any Jersey Devil has been washing up on beaches in the Garden State lately: This month, the dangerous Portuguese Man O’ War—which has a potentially deadly sting—has been sighted in Cape May and Wildwood, New Jersey, which could lead to problems for beachgoers. Read on to learn more about these unusual creatures.

1. IT'S NOT A JELLYFISH.

The Portuguese Man o’ War may look like a bloated jellyfish, but it’s actually a siphonophore—a bizarre group of animals that consist of colonies made up of dozens, hundreds, or even thousands of genetically-identical individual creatures. A siphonophore starts out as a fertilized egg. But as it develops, it starts "budding" into distinct structures and organisms. These tiny organisms—called polyps or zooids—can’t survive on their own, so they merge together into a tentacled mass. They must cooperate as one in order to do things like travel and catch food.

Though the zooids within a Man O’ War are basically clones, they come in different shapes and serve different purposes [PDF]. Dactylozooids are long hunting tentacles built to ensnare prey; gastrozooids are smaller tentacles which digest the food; and gonozooids are dangling entities whose job is to facilitate reproduction. Every Man O’ War also has a pneumatophore, or “float”—an overgrown, bag-like polyp which acts as a giant gas bladder and sits at the top of the colony. Capable of expanding or contracting at will, it provides the Man O’ War with some buoyancy control. An expanded float also enables the colony to harness winds to move around.

2. A CLOSE RELATIVE IS THE INDO-PACIFIC “BLUEBOTTLE.”

A view of a bluebottle under water.
iStock

When we say “Portuguese Man O’ War,” we’re talking about Physalia physalis, the bizarre siphonophore that’s scaring New Jerseyans right now. Also known as the Atlantic Portuguese Man O’ War, it can be found in warmer parts of the Pacific, the Caribbean, the Indian Ocean, and of course, the Atlantic.

Another kind of siphonophore which regularly stings beachgoers is the so-called bluebottle, Physalia utriculus. It’s sometimes called the Indo-Pacific “Portuguese” Man O’ War and is restricted to the Pacific and Indian Oceans. It’s smaller than the Atlantic species and unlike its bigger counterpart—which has multiple hunting tentacles—it hunts with a single, elongated tentacle.

3. THE NAME “PORTUGUESE MAN O’ WAR” IS PROBABLY A NAVAL REFERENCE.

In the age of sailing, many European navies used tall warships loaded with cannons and propelled by three masts. British sailors took to calling this kind of vessel a “Man of War.”

What does that have to do with Physalia physalias? These colonies spend a lot of time floating at the water’s surface, and when the gas bladder is expanded, it looks—and acts—a bit like a sailboat, hence the “Man O’ War.” As for the Portuguese part, 19th century scientists proposed that sailors encountered it near the Portuguese island of Madeira, while modern etymologists tend to think that it looked like the Portuguese version of the ship.

Or at least that’s one explanation for the creature’s peculiar name. It’s also been suggested that Renaissance-era sailors thought the pneumatophores resembled the helmets worn by Portugal’s soldiers during the 16th century.

4. MAN O’ WAR TENTACLES CAN BE UP TO 165 FEET LONG.

Two Portuguese Man o' War washed up on the beach with their tentacles stretched out.
iStock

At least, that’s the maximum length for the dactylozooids—which are normally around 30 feet long and use venom-spewing cells to deliver painful, neurotoxic stings. When a tentacle is detached from the rest of the colony, it might wash ashore somewhere or drift around for days on end until it decomposes. Be warned: Even a severed tentacle can sting you.

5. ON RARE OCCASIONS, STINGS CAN BE FATAL TO HUMANS.

The odds of being killed by a Portuguese Man O’ War are slim. But just because deaths are rare doesn't mean you should touch one: On February 11, 2018, 204 people in Hollywood, Florida were treated for stings, which can lead to red welts on the skin, muscle cramps, elevated heart rates, and vomiting.

Still, the creatures can kill: One unlucky victim suffered a full cardiovascular collapse and died after getting too close to a Man O’ War in eastern Florida back in 1987. More recently, a woman swimming off Sardinia was stung by one and died of what was believed to be anaphylactic shock.

6. SOME FISH LIVE IN THEM.

Given that tiny fish make up about 70 to 90 percent of the Man O’ War’s diet (it also eats shrimp and other crustaceans), Nomeus gronovii, a.k.a. the Portuguese Man O’ War Fish, is playing a dangerous game: It lives among the siphonophore's tentacles even though it's not immune to its stings, swimming nimbly between the stingers. Young fish eat planktons which wander under their hosts and, as they get older, will sometimes steal the Man O’ War’s prey—or nibble on its tentacles.

7. SEA SLUGS LIKE TO STEAL THEIR TOXINS.

The Man O’ War has a long list of enemies. Loggerhead sea turtles and the bizarre-looking ocean sunfish are thick-skinned enough to eat them. There are also “blue dragon” sea slugs, which not only devour the Man O’ War but actively harvest and appropriate its toxins. After storing Man O’ War stinging cells in their own skins, the blue dragons can use it as a predator deterrent.

8. MAN O’ WAR COME IN PRETTY COLORS.

A pink-tinted Portuguese Man O' War with blue tentacles in the surf at a beach.
iStock

Although it’s translucent, the float is usually tinted with blue, pink, and/or purple hues. Beaches along the American Gulf Coast raise purple flags in order to let visitors know when groups of Man O’ War (or other potentially deadly sea creatures) are at large.

9. EVERY COLONY HAS A SPECIFIC SEX.

The Man O' War's gonozooids have sacs that house ovaries or testes—so each colony can therefore be considered “male” or “female.” Though marine biologists aren’t completely sure how the Man O’ War procreates, one theory is that the gonozooids release eggs and sperm into the open ocean, which become fertilized when they cross paths with floating eggs or sperm from other Man O’ War colonies. This “broadcast spawning” method of reproduction is also used by many species of coral, fan worms, sea anemone, and jellyfish.

10. LOOK OUT FOR MAN O’ WAR LEGIONS.

The Man O’ War isn't always seen in isolation. Legions consisting of over 1000 colonies have been observed floating around together. Because they drift along on (somewhat) predictable winds and ocean currents, it’s possible to anticipate where and when a lot of the creatures will show up. For example, the Gulf Coast’s Man O’ War season arrives in the winter months.

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