Scientists Devise Clever Way to Test Old Manuscripts’ DNA

Jim Forest, Flickr Creative Commons // CC BY-NC-ND 2.0
Jim Forest, Flickr Creative Commons // CC BY-NC-ND 2.0

When encountering an obstacle, some people stop and give up, some force their way through, and others find another way around. That's what scientists in the United Kingdom have done with a delicate manuscript from the Dark Ages. Barred from taking parchment samples, the resourceful researchers instead analyzed the eraser crumbs left behind after archivists cleaned the paper. They describe their findings in an article on the prepress server bioRxiv.

Co-author and archaeologist Matthew Collins of the University of York did not start out a manuscript man. Collins had been trying to extract DNA from animal bones unearthed at a Viking settlement to learn more about the culture's use of livestock. But the bones had decayed too far to offer much in the way of genetic material. "You can imagine the frustration," Collins said in an interview with The Atlantic.

Then he realized that animal remains can be more than just bones. There are skins, too—and those, at least, we've taken some pains to preserve. At least the ones we've written on.

"You look at [archive] shelves," Collins said, "and every one of them has a skin of an animal with a date written on it."

Collins's excitement at discovering this untapped bounty of data was soon tempered when he and his collaborator, biochemist Sarah Fiddyment, learned that sampling the manuscripts was completely off-limits.

But they weren't about to give up that easily. Fiddyment spent weeks following the conservators as they worked with the fragile animal-skin paper, learning their process and watching for possible openings. Finally, she saw it: eraser crumbs.

Conservators routinely use PVC erasers to lift stains, grime, and damage from historic documents. The friction created by gently rubbing the eraser against the paper creates an electric charge that pulls in molecules of dirt and oil. And probably other things, too, Fiddyment thought.

Fiddyment, Collins, and their colleagues began collecting eraser crumbs from manuscript conservators around the world. They analyzed each document's chemical makeup and were even able to compare proteins to identify the livestock species responsible for the skin.

The next step was to look at the DNA itself. The researchers turned to the York Gospels, a leatherbound Bible with pages dating back to the year 990. By collecting another tiny pile of eraser crumbs from cleanup of eight pages, they were able to collect enough of a sample to run thorough DNA tests.

Those pages had quite a lot to say about their creation and history. The tests revealed 1000-year-old genetic material from the cows and sheep that gave the book its parchment pages. Remarkably, the DNA was so intact that the scientists could identify the cows' ancestry (something close to our modern-day Norwegian reds and Holsteins) and sex (mostly female).

The pages also contained human DNA and even bacteria, most likely from the hands and saliva of the people who made, wrote, and used the book.

Speaking to The Atlantic, parchment expert Bruce Holsinger of the University of Virginia called the findings "an exciting breakthrough."

[h/t The Atlantic]

No Venom, No Problem: This Spider Uses a Slingshot to Catch Prey

Courtesy of Sarah Han
Courtesy of Sarah Han

There are thousands of ways nature can kill, and spider species often come up with the most creative methods of execution. Hyptiotes cavatus, otherwise known as the triangle weaver spider, is one such example. Lacking venom, the spider manages to weaponize its silk, using it to hurl itself forward like a terrifying slingshot to trap its prey.

This unusual method was studied up close for a recent paper published in the Proceedings of the National Academy of Sciences by researchers at the University of Akron in Ohio. They say it's the only known instance of an animal using an external device—its web—for power amplification.

Hyptiotes cavatus's technique is simple. After constructing a web, the spider takes one of the main strands and breaks it in half, pulling it taut by moving backwards. Then, it anchors itself to a spot with more webbing in the rear. When the spider releases that webbing, it surges forward, propelled by the sudden release of stored energy. In the slingshot analogy, the webbing is the strap and the spider is the projectile.

This jerking motion causes the web to oscillate, tangling the spider's prey further in silk. The spider can repeat this until the web has completely immobilized its prey, a low-risk entrapment that doesn’t require the spider to get too close and risk injury from larger victims.

The triangle weaver spider doesn’t have venom, and it needs to be proactive in attacking and stifling prey. Once a potential meal lands in its web, it’s able to clear distances much more quickly using this slingshot technique than if it crawled over. In the lab, scientists clocked the spider’s acceleration at 2535 feet per second squared.

Spiders are notoriously nimble and devious. Cebrennus rechenbergi, or the flic-flac spider, can do cartwheels to spin out of danger; Myrmarachne resemble ants and even wiggle their front legs like ant antennae. It helps them avoid predators, but if they see a meal, they’ll drop the act and pounce. With H. cavatus, it now appears they’re learning to use tools, too.

[h/t Live Science]

Bad News: The Best Time of the Day to Drink Coffee Isn’t as Soon as You Wake Up

iStock.com/ThomasVogel
iStock.com/ThomasVogel

If you depend on coffee to help get you through the day, you can rest assured that you’re not the world's only caffeine fiend. Far from it. According to a 2018 survey, 64 percent of Americans said they had consumed coffee the previous day—the highest percentage seen since 2012.

While we’re collectively grinding more beans, brewing more pots, and patronizing our local coffee shops with increased frequency, we might not be maximizing the health and energy-boosting benefits of our daily cup of joe. According to Inc., an analysis of 127 scientific studies highlighted the many benefits of drinking coffee, from a longer average life span to a reduced risk for cancer, heart disease, type 2 diabetes, and Parkinson’s disease.

Sounds great, right? The only problem is that the benefits of coffee might be diminished depending on the time of day that you drink it. Essentially, science tells us that it’s best to drink coffee when your body’s cortisol levels are low. That’s because both caffeine and cortisol cause a stress response in your body, and too much stress is bad for your health for obvious reasons. In addition, it might end up making you more tired in the long run.

Cortisol, a stress hormone, is released in accordance with your circadian rhythms. This varies from person to person, but in general, someone who wakes up at 6:30 a.m. would see their cortisol levels peak in different windows, including 8 to 9 a.m., noon to 1 p.m., and 5:30 to 6:30 p.m. Someone who rises at 10 a.m. would experience cortisol spikes roughly three hours later, and ultra-early risers can expect to push this schedule three hours forward.

However, these cortisol levels start to rise as soon as you start moving in the morning, so it isn’t an ideal time to drink coffee. Neither is the afternoon, because doing so could make it more difficult to fall asleep at night. This means that people who wake up at 6:30 a.m. should drink coffee after that first cortisol window closes—roughly between 9:30 a.m. and 11:30 a.m.—if they want to benefit for a little caffeine jolt.

To put it simply: "I would say that mid-morning or early afternoon is probably the best time," certified dietitian-nutritionist Lisa Lisiewski told CNBC. "That's when your cortisol levels are at their lowest and you actually benefit from the stimulant itself."

[h/t Inc.]

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