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10 Terrific Facts About Trilobites

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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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Scientists Discover 'Octlantis,' a Bustling Octopus City
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Sylke Rohrlach, Wikimedia Commons // CC BY-SA 4.0

Octopuses are insanely talented: They’ve been observed building forts, playing games, and even walking on dry land. But one area where the cephalopods come up short is in the social department. At least that’s what marine biologists used to believe. Now a newly discovered underwater community, dubbed Octlantis, is prompting scientists to call their characterization of octopuses as loners into question.

As Quartz reports, the so-called octopus city is located in Jervis Bay off Australia’s east coast. The patch of seafloor is populated by as many as 15 gloomy octopuses, a.k.a. common Sydney octopuses (octopus tetricus). Previous observations of the creatures led scientists to think they were strictly solitary, not counting their yearly mating rituals. But in Octlantis, octopuses communicate by changing colors, evict each other from dens, and live side by side. In addition to interacting with their neighbors, the gloomy octopuses have helped build the infrastructure of the city itself. On top of the rock formation they call home, they’ve stored mounds of clam and scallop shells and shaped them into shelters.

There is one other known gloomy octopus community similar to this one, and it may help scientists understand how and why they form. The original site, called Octopolis, was discovered in the same bay in 2009. Unlike Octlantis, Octopolis was centered around a manmade object that had sunk to the seabed and provided dens for up to 16 octopuses at a time. The researchers studying it had assumed it was a freak occurrence. But this new city, built around a natural habitat, shows that gloomy octopuses in the area may be evolving to be more social.

If that's the case, it's unclear why such octo-cities are so uncommon. "Relative to the more typical solitary life, the costs and benefits of living in aggregations and investing in interactions remain to be documented," the researchers who discovered the group wrote in a paper published in Marine and Freshwater Behavior and Physiology [PDF].

It’s also possible that for the first time in history humans have the resources to see octopus villages that perhaps have always been bustling beneath the sea surface.

[h/t Quartz]

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Criminal Gangs Are Smuggling Illegal Rhino Horns as Jewelry
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Valuable jewelry isn't always made from precious metals or gems. Wildlife smugglers in Africa are increasingly evading the law by disguising illegally harvested rhinoceros horns as wearable baubles and trinkets, according to a new study conducted by wildlife trade monitoring network TRAFFIC.

As BBC News reports, TRAFFIC analyzed 456 wildlife seizure records—recorded between 2010 and June 2017—to trace illegal rhino horn trade routes and identify smuggling methods. In a report, the organization noted that criminals have disguised rhino horns in the past using all kinds of creative methods, including covering the parts with aluminum foil, coating them in wax, or smearing them with toothpaste or shampoo to mask the scent of decay. But as recent seizures in South Africa suggest, Chinese trafficking networks within the nation are now concealing the coveted product by shaping horns into beads, disks, bangles, necklaces, and other objects, like bowls and cups. The protrusions are also ground into powder and stored in bags along with horn bits and shavings.

"It's very worrying," Julian Rademeyer, a project leader with TRAFFIC, told BBC News. "Because if someone's walking through the airport wearing a necklace made of rhino horn, who is going to stop them? Police are looking for a piece of horn and whole horns."

Rhino horn is a hot commodity in Asia. The keratin parts have traditionally been ground up and used to make medicines for illnesses like rheumatism or cancer, although there's no scientific evidence that these treatments work. And in recent years, horn objects have become status symbols among wealthy men in countries like Vietnam.

"A large number of people prefer the powder, but there are those who use it for lucky charms,” Melville Saayman, a professor at South Africa's North-West University who studies the rhino horn trade, told ABC News. “So they would like a piece of the horn."

According to TRAFFIC, at least 1249 rhino horns—together weighing more than five tons—were seized globally between 2010 and June 2017. The majority of these rhino horn shipments originated in southern Africa, with the greatest demand coming from Vietnam and China. The product is mostly smuggled by air, but routes change and shift depending on border controls and law enforcement resources.

Conservationists warn that this booming illegal trade has led to a precipitous decline in Africa's rhinoceros population: At least 7100 of the nation's rhinos have been killed over the past decade, according to one estimate, and only around 25,000 remain today. Meanwhile, Save the Rhino International, a UK-based conservation charity, told BBC News that if current poaching trends continue, rhinos could go extinct in the wild within the next 10 years.

[h/t BBC News]

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