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DNA of Ancient Cats Traces the Path of Their Global Conquest

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A new study of ancient DNA presented at the 7th International Symposium on Biomolecular Archaeology has revealed the secret story of cats’ spread across the globe.

Cats are mysterious creatures. They’re independent yet social, aloof yet endearing, and very good at getting what they want. Like any organism, the very first cats originated in one place, then spread. They spread, and spread, and continue to spread, becoming beloved pets and conservationists’ worst nightmare, often at the same time.

Exactly how they managed this feat of feline world domination has remained something of a puzzle. How did these small, terrestrial animals make it across the oceans? Cats have no value as livestock (like cows) or transport (like horses). They’re good workers as mousers, but only when they want to be. And we talk about the "domestic" cat, but some scientists think that may be a misnomer—maybe we haven’t really domesticated them at all.

But they may have domesticated us. Look back 12,000 years in time to the Fertile Crescent at the dawn of agriculture, when cats were buried along with people. Look to the millions of sacred cats mummified in ancient Egypt. Every time we find the carefully entombed remains of a cat, we find a clue to how they got to be who (and where) they are today.

Researchers lead by Eva-Maria Geigl, an evolutionary geneticist at the Institut Jacques Monod in Paris, sequenced DNA taken from the remains of 209 cats found at more than 30 archaeological digs across Africa, the Middle East, and Europe. They focused exclusively on mitochondrial DNA, which is inherited maternally. The samples represented an enormous swath of history, from our days as hunter-gatherers up through the 18th century.

The cats’ DNA painted a picture of two distinct bursts of kitty scattering (s-cat-tering, if you will). The first was in the Middle East, where farming began about 10,000 years ago. As farming communities grew out toward the Mediterranean Sea, the cats came with them. The study authors say the farms’ piles of grain likely attracted rodents, which then brought out the wild cats. And once farmers saw the value of having fierce mousers around, they likely tried to find a way to keep them.

Fast-forward several millennia to the second wave, when noble Egyptian cats began to sow their wild oats throughout Eurasia and Africa. A family line found in Egyptian mummy cats from the end of the fourth century BCE to the fourth century CE was also found in cats from Bulgaria, Turkey, and sub-Saharan Africa during roughly the same time.

Then they hit up the Vikings. Seafaring life is a tangle of dangers and threats, including the voracious mouths of rats and mice in a hold full of essential provisions. By around the 8th century, Vikings, too, had seen the value of keeping cats around, as evidenced by feline remains found in Viking settlements.

And still they spread. Cats are something of a contentious topic these days. The hunting skills that made them so attractive to our distant ancestors can today make them a serious threat to wildlife. Some places have banned cats altogether, although it might already be too late—they've already got us thoroughly wrapped around their little paws.

[h/t Nature]

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Big Questions
Why Don't We Eat Turkey Tails?
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Turkey sandwiches. Turkey soup. Roasted turkey. This year, Americans will consume roughly 245 million birds, with 46 million being prepared and presented on Thanksgiving. What we don’t eat will be repurposed into leftovers.

But there’s one part of the turkey that virtually no family will have on their table: the tail.

Despite our country’s obsession with fattening, dissecting, and searing turkeys, we almost inevitably pass up the fat-infused rear portion. According to Michael Carolan, professor of sociology and associate dean for research at the College for Liberal Arts at Colorado State University, that may have something to do with how Americans have traditionally perceived turkeys. Consumption was rare prior to World War II. When the birds were readily available, there was no demand for the tail because it had never been offered in the first place.

"Tails did and do not fit into what has become our culinary fascination with white meat," Carolan tells Mental Floss. "But also from a marketing [and] processor standpoint, if the consumer was just going to throw the tail away, or will not miss it if it was omitted, [suppliers] saw an opportunity to make additional money."

Indeed, the fact that Americans didn't have a taste for tail didn't prevent the poultry industry from moving on. Tails were being routed to Pacific Island consumers in the 1950s. Rich in protein and fat—a turkey tail is really a gland that produces oil used for grooming—suppliers were able to make use of the unwanted portion. And once consumers were exposed to it, they couldn't get enough.

“By 2007,” according to Carolan, “the average Samoan was consuming more than 44 pounds of turkey tails every year.” Perhaps not coincidentally, Samoans also have alarmingly high obesity rates of 75 percent. In an effort to stave off contributing factors, importing tails to the Islands was banned from 2007 until 2013, when it was argued that doing so violated World Trade Organization rules.

With tradition going hand-in-hand with commerce, poultry suppliers don’t really have a reason to try and change domestic consumer appetites for the tails. In preparing his research into the missing treat, Carolan says he had to search high and low before finally finding a source of tails at a Whole Foods that was about to discard them. "[You] can't expect the food to be accepted if people can't even find the piece!"

Unless the meat industry mounts a major campaign to shift American tastes, Thanksgiving will once again be filled with turkeys missing one of their juicier body parts.

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10 Juicy Facts About Sea Apples

They're both gorgeous and grotesque. Sea apples, a type of marine invertebrate, have dazzling purple, yellow, and blue color schemes streaking across their bodies. But some of their habits are rather R-rated. Here’s what you should know about these weird little creatures.


The world’s oceans are home to more than 1200 species of sea cucumber. Like sand dollars and starfish, sea cucumbers are echinoderms: brainless, spineless marine animals with skin-covered shells and a complex network of internal hydraulics that enables them to get around. Sea cucumbers can thrive in a range of oceanic habitats, from Arctic depths to tropical reefs. They're a fascinating group with colorful popular names, like the “burnt hot dog sea cucumber” (Holothuria edulis) and the sea pig (Scotoplanes globosa), a scavenger that’s been described as a “living vacuum cleaner.”


Sea apples have oval-shaped bodies and belong to the genus Pseudocolochirus and genus Paracacumaria. The animals are indigenous to the western Pacific, where they can be found shuffling across the ocean floor in shallow, coastal waters. Many different types are kept in captivity, but two species, Pseudocolochirus violaceus and Pseudocolochirus axiologus, have proven especially popular with aquarium hobbyists. Both species reside along the coastlines of Australia and Southeast Asia.


Sea cucumbers, the ocean's sanitation crew, eat by swallowing plankton, algae, and sandy detritus at one end of their bodies and then expelling clean, fresh sand out their other end. Sea apples use a different technique. A ring of mucus-covered tentacles around a sea apple's mouth snares floating bits of food, popping each bit into its mouth one at a time. In the process, the tentacles are covered with a fresh coat of sticky mucus, and the whole cycle repeats.


Sea apples' waving appendages can look delicious to predatory fish, so the echinoderms minimize the risk of attracting unwanted attention by doing most of their feeding at night. When those tentacles aren’t in use, they’re retracted into the body.


The rows of yellow protuberances running along the sides of this specimen are its feet. They allow sea apples to latch onto rocks and other hard surfaces while feeding. And if one of these feet gets severed, it can grow back.


Sea apples are poisonous, but a few marine freeloaders capitalize on this very quality. Some small fish have evolved to live inside the invertebrates' digestive tracts, mooching off the sea apples' meals and using their bodies for shelter. In a gross twist of evolution, fish gain entry through the back door, an orifice called the cloaca. In addition expelling waste, the cloaca absorbs fresh oxygen, meaning that sea apples/cucumbers essentially breathe through their anuses.


Most full-grown adult sea apples are around 3 to 8 inches long, but they can make themselves look twice as big if they need to escape a threat. By pulling extra water into their bodies, some can grow to the size of a volleyball, according to Advanced Aquarist. After puffing up, they can float on the current and away from danger. Some aquarists might mistake the robust display as a sign of optimum health, but it's usually a reaction to stress.


Sea apples use their vibrant appearance to broadcast that they’re packing a dangerous toxin. But to really scare off predators, they puke up some of their own innards. When an attacker gets too close, sea apples can expel various organs through their orifices, and some simultaneously unleash a cloud of the poison holothurin. In an aquarium, the holothurin doesn’t disperse as widely as it would in the sea, and it's been known to wipe out entire fish tanks.


These invertebrates reproduce sexually; females release eggs that are later fertilized by clouds of sperm emitted by the males. As many saltwater aquarium keepers know all too well, sea apple eggs are not suitable fish snacks—because they’re poisonous. Scientists have observed that, in Pseudocolochirus violaceus at least, the eggs develop into small, barrel-shaped larvae within two weeks of fertilization.


Syzgium grande is a coastal tree native to Southeast Asia whose informal name is "sea apple." When fully grown, they can stand more than 140 feet tall. Once a year, it produces attractive clusters of fuzzy white flowers and round green fruits, perhaps prompting its comparison to an apple tree.


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