‘Lost’ Galapagos Tortoise Species Could Make a Comeback

Score one for the giant tortoise: The descendants of one thought-to-be extinct species have apparently been chilling on the side of a volcano, eating grass for the last few hundred years. Scientists say breeding these animals could bring the species back from the brink. A report on the tortoise surprise was published on the preprint server bioRxiv.

Once upon a time, the Galapagos archipelago was a veritable paradise for 15 different species of giant tortoise. Then, humans showed up and the lumbering slowpokes began to disappear with alarming speed. Three centuries of human depredation wiped out 90 percent of the islands’ tortoises. Four entire species, including Floreana (Chelonoidis elephantopus) and Pinta (C. abingdoni) tortoises, completely disappeared. Or so we thought.

Then in 2008, DNA tests revealed that 105 of the tortoises living on Floreana Island had some C. elephantopus blood in their veins, mingled with ancestry from another species on the island. None of the tortoises were purebred, but scientists’ curiosity was piqued.

Seven years later, a team of 70 field researchers set out to see if they could find more. And there, on the grassy side of a volcano, they did: 144 tortoises with C. elephantopus’s distinctive saddle-shaped shell.

Blood tests from the volcano dwellers and six tortoises already in the islands’ captive breeding program revealed a rich field of Floreana tortoise DNA. Most of the samples included some of the thought-extinct species’ DNA, and two individuals appeared to be 100 percent, uncut C. elephantopus.

The researchers collected 23 of the tortoises, including the two apparent purebreds, and added them to the captive breeding program—after checking to make sure none of them were related. A few generations of baby tortoises would be enough to bring the species back.

Craig Stanford is a tortoise and turtle expert at the International Union for Conservation of Nature. He was not involved with the research but expressed excitement about the possibility of bringing Floreana tortoises back.

“We have the opportunity to restore a critically rare and biologically remarkable species to its natural habitat, which is an amazing chance that doesn’t come along very often,” he told New Scientist. “I’m cautiously optimistic about the odds of success.”

The paper’s authors note that the rogue population on the volcano’s slopes may be the result of the same human interference that obliterated the rest of the species. “Ironically, it was the haphazard translocations by mariners killing tortoises for food centuries ago that created the unique opportunity to revive this ‘lost’ species today.”

[h/t New Scientist]

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'Lime Disease' Could Give You a Nasty Rash This Summer
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A cold Corona or virgin margarita is best enjoyed by the pool, but watch where you’re squeezing those limes. As Slate illustrates in a new video, there’s a lesser-known “lime disease,” and it can give you a nasty skin rash if you’re not careful.

When lime juice comes into contact with your skin and is then exposed to UV rays, it can cause a chemical reaction that results in phytophotodermatitis. It looks a little like a poison ivy reaction or sun poisoning, and some of the symptoms include redness, blistering, and inflammation. It’s the same reaction caused by a corrosive sap on the giant hogweed, an invasive weed that’s spreading throughout the U.S.

"Lime disease" may sound random, but it’s a lot more common than you might think. Dermatologist Barry D. Goldman tells Slate he sees cases of the skin condition almost daily in the summer. Some people have even reported receiving second-degree burns as a result of the citric acid from lime juice. According to the Mayo Clinic, the chemical that causes phytophotodermatitis can also be found in wild parsnip, wild dill, wild parsley, buttercups, and other citrus fruits.

To play it safe, keep your limes confined to the great indoors or wash your hands with soap after handling the fruit. You can learn more about phytophotodermatitis by checking out Slate’s video below.

[h/t Slate]

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Why Eating From a Smaller Plate Might Not Be an Effective Dieting Trick 
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It might be time to rewrite the diet books. Israeli psychologists have cast doubt on the widespread belief that eating from smaller plates helps you control food portions and feel fuller, Scientific American reports.

Past studies have shown that this mind trick, called the Delboeuf illusion, influences the amount of food that people eat. In one 2012 study, participants who were given larger bowls ended up eating more soup overall than those given smaller bowls.

However, researchers from Ben-Gurion University in Negev, Israel, concluded in a study published in the journal Appetite that the effectiveness of the illusion depends on how empty your stomach is. The team of scientists studied two groups of participants: one that ate three hours before the experiment, and another that ate one hour prior. When participants were shown images of pizzas on serving trays of varying sizes, the group that hadn’t eaten in several hours was more accurate in assessing the size of pizzas. In other words, the hungrier they were, the less likely they were to be fooled by the different trays.

However, both groups were equally tricked by the illusion when they were asked to estimate the size of non-food objects, such as black circles inside of white circles and hubcaps within tires. Researchers say this demonstrates that motivational factors, like appetite, affects how we perceive food. The findings also dovetail with the results of an earlier study, which concluded that overweight people are less likely to fall for the illusion than people of a normal weight.

So go ahead and get a large plate every now and then. At the very least, it may save you a second trip to the buffet table.

[h/t Scientific American]

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