Shell Shape Helps Tortoises Get Up

By Matt Benoit | November 30, 2017 8:59 am
tortoise-shell-galapagos-island-fall-get-up

A tortoise’s shell shape can help determine how quickly it can turn right side up after falling on its back. (Credit: YouTube/Bio Insider)

It’s tough being an adult giant tortoise in the Galapagos Islands—they’re always one step away from flipping upside down. Whether it’s from a fight for male dominance or treading over a jagged field of lava rocks, being unable to get back up is among the most common ways these giant tortoises can die.

There is no Life Alert button to press for help. Instead, these animals must rely on their ability to flip over and keep on living. Luckily, many Galapagos tortoises are successful at doing so. It’s referred to as “self-righting,” and is the focus of a new study published Thursday in Nature Scientific Reports.

Ylenia Chiari, an evolutionary biologist at the University of South Alabama, led a group of scientists that tested several tortoise shell varieties to note the differences in how these creatures right themselves. This is the first study of its kind to show two different shell types differing in the energy required for the tortoises to self-right.

Shell Shape Matters

Chiari and her colleagues used 3D shell reconstructions of 89 adult tortoises–three species of domed tortoises and two species of saddleback tortoises–to compare the self-righting potential of the two shell types and see which would require less energy to overturn.

They realized that ones with the same shell shape used similar strategies to get back up. The domed tortoises, with more rounded shell shapes, wave their legs around. Saddlebacks, with flatter shells, also wave their legs, but are thought to use their neck to push against the ground to give them momentum to turn over.

tortoise-shell-shape-turn

The domed shells are more rounded, while the saddlebacks are flatter. (Credit: YouTube/Bio Insider)

Chiari says these two types of tortoises provide an ideal system to study, because when born, the two appear identical. But as they grow, their shell shapes and adaptive traits emerge.

“You have all these different species on the Galapagos, and you have these different shells that basically evolve multiple times,” she says. “So, it’s a very neat system, because it means, probably, these different shells work well for something. The question is: what is this something? And the real answer is we still don’t know.”

Which Came First: The Tortoise or Its Shell

Chiari says they hypothesized that the saddleback, because of their drier, lower-elevation environment, would fall on their backs more often. Because of a higher temperature climate, she says they were expected to flip more easily and more often.

But that wasn’t the case. Instead, the saddlebacks required more energy to right themselves than the domed tortoises, suggesting that several traits with the saddleback shell type could have evolved to help them flip over.

Is that due to the shell itself? Chiari says it may not be, because on data alone, scientists haven’t established which came first: the saddleback’s longer neck, or the shape of the shell itself, which has a taller anterior opening for its neck. This allows the tortoise greater movement, and helps them self-right more quickly.

And Chiari says there is still more data to analyze with regard to tortoise shells.

“We still don’t know how the shells perform differently for a bunch of other functions,” she says.

In the future, Chiari hopes to explore the differences of tortoises on a genetic and molecular level. She compares these shell variations to the variations in the height of people. Some are tall, some are short, but regardless of that fact, each adapts to carry out the same tasks in different ways.

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: animals

Prehistoric Females Were Strong As Hell

By Leah Froats | November 29, 2017 1:00 pm
A Sri Lankan woman grinds flour by hand, similar to how prehistoric women may have. (Credit: By Adam P/Shutterstock)

A Sri Lankan woman grinds flour by hand, similar to how prehistoric women may have. (Credit: Adam P/Shutterstock)

Compared to hunting and gathering, farming can seem like pretty easy work. But the skeletons of Central European women who lived during agriculture’s earliest days would like to tell you otherwise.

An analysis of prehistoric women’s upper arm bones shows they took on formidable tasks of manual labor, likely during the course of tilling, harvesting and otherwise managing farm fields.

And the hard work left them pretty beasty — it was enough to make them stronger even than modern female competitive athletes today, researchers say.

Bad to the Bone 

Cambridge archaeologist Alison Macintosh led a team of scientists who published a study Wednesday in Science Advances comparing the bone structure of modern female athletes to female farmers in the Neolithic period and Bronze and Iron Ages.

Not only is this the first study to compare the bones of ancient women to those of women today, but the research is also notable for not using male skeletons as a comparison point.

Previous bioarchaeological studies of prehistoric behavior compared the skeletons of women directly to the skeletons of men. Because men’s bones bulk up more noticeably in response to strain, these studies made it appear as though women weren’t doing a lot of the heavy lifting — both literally and figuratively.

The researchers say these unequal male-to-female skeletal comparisons have resulted in an underestimation of the physical tasks women took on in ancient times. It’s also obscured some of the differences in how men and women worked.

With laser scans and molds, the researchers analyzed arm and leg bones from female skeletons thousands of years old. Assessing the bones’ shape and rigidity let them ascertain the amount and type of physical strain endured by prehistoric women. Things like tilling soil, harvesting crops, and grinding grain for as much as five hours a day to make flour made them exceptionally strong, the researchers say.

This is in comparison to ancient men, whose leg bones show signs of increased strain, indicating a focus on hunting and gathering.

“By interpreting women’s bones in a female-specific context we can start to see how intensive, variable and laborious their behaviors were, hinting at a hidden history of women’s work over thousands of years,” said Macintosh.

Bone density and content is widely variable depending on factors such as diet and age, so we should be a bit cautious in our interpretations, but the researchers’ findings are clear — prehistoric women shouldered a much greater load than we thought.

A Contemporary Comparison

To get a more accurate picture of how ancient females stacked up, the researchers then compared them to the bones of contemporary female athletes, instead of men.

The researchers took CT scans of modern sedentary women as well as female rowers, endurance runners, and soccer players at Cambridge.

They found that Neolithic women’s leg bones were about as strong as those of modern rowers, but their arm bones were significantly stronger — about 11-16 percent. Compared to sedentary students, the gap was as high as 30 percent.

But other than the fact that these women were quite strong, there are other useful findings as well. Women’s leg bone strength appears to decrease between the Neolithic and the Bronze Age, indicating that men and women’s activities began to increasingly diverge. Women became less mobile as they focused on agriculture, shifting the load to their arms instead.

It’s an indication that women played an integral role in the development of agriculture across Europe. In addition, the study highlights the importance of comparing prehistoric female behavior to that of other females, bringing new light to the lived experience of women through the ages.

CATEGORIZED UNDER: Living World
MORE ABOUT: archaeology

Two Teams Create “Quantum Simulators”

By Bill Andrews | November 29, 2017 12:00 pm
Each horizontal line is a snapshot of a single atom, the dark and light indicating its magnetic state. (Credit: Data: J. Zhang et al.; graphic: E. Edwards)

Each horizontal line is a snapshot of a single atom, whether its lit up or not indicates the atom’s magnetic state. (Credit: Data: J. Zhang et al.; graphic: E. Edwards)

Science, especially these days, can move slowly. The days of big leaps in our understanding are mostly behind us, and the progress of scientists is typically slow, but steady. That’s why something like quantum computers, which you’ve probably heard a lot about, have been so slow to actually arrive. Read More

CATEGORIZED UNDER: Space & Physics, Technology

Patients Say Poop Pills Are Both Effective and Preferable

By Nathaniel Scharping | November 28, 2017 3:32 pm
What fecal transplant pills could look like in the future. (Credit: Marc Bruxelle/Shutterstock)

What fecal transplant pills could look like in the future. (Credit: Marc Bruxelle/Shutterstock)

Swallowing poop is ok.

That’s the conclusion of a recent study assessing the effectiveness of fecal microbiota transplants (FMT) delivered in pill form, versus given by colonoscopy. It sounds a bit off-putting, but validating the safety and efficacy of fecal capsules could give patients with gut diseases a cheaper and less invasive option for treatment.

The study, published Tuesday in the Journal of the American Medical Association, took place in patients suffering from recurring Clostridium difficile infections, a bacterial infection that often takes hold in the gut after courses of antibiotics. Those drugs can wipe out normal gut bacteria, allowing harmful species like C. difficile to flourish. Symptoms include inflammation of the colon, cramping and severe ongoing diarrhea, and FMT aims to undo the damage by restoring the proper species of bacteria to the digestive system.

Bottom-to-Top Solution

A fecal transplant is pretty much what it sounds like. Recipients take poop donated from someone else — containing a dose of healthy gut bacteria — and implant it into their own digestive systems. The goal is to reboot or replenish the colonies of microorganisms essential to digestive processes, kicking out harmful ones like C. difficile.

The usefulness of fecal transplants in treating C. difficile infections has been demonstrated in multiple previous studies, but most of those involved the use of colonoscopies or enemas to get the bacteria where they needed to go. That works, but it also involves swimming upstream, so to speak. Doses of bacteria inside a pill make their way to our digestive systems in a much more natural fashion.

There’s been evidence that pills would accomplish the same thing as a colonoscopy, but reason for caution as well. Preliminary studies from OpenBiome, a non-profit organization that maintains a stool bank and which hopes to market fecal transplant pills, indicated that the pills worked. On the other hand, a study from Massachusetts-based Seres Therapeutics based on a version of the pill containing just bacterial spores failed to show any real benefit.

Helpful Little Pill

Here, researchers from the University of Alberta and the University of Calgary again tested patients suffering from recurrent C difficile infections. Of 116 subject, roughly half got FMT via colonoscopy and the rest took pills containing the same fecal mixture. After 12 weeks of observation, about 96 percent of patients in both groups had recovered from their infections. The pills didn’t affect the quality of the treatment at all, it seems. More patients receiving pills, however, rated their treatment as “not at all unpleasant,” a result that agrees with a 2012 study finding that most patients would choose a pill over other methods of FMT.

The only downside, as one patient noted, was the sheer number of pills. Participants had to down 40 within an hour, or one dose every minute and a half. Even if they tasted like Flintstone multivitamins, that’s a tall order. In reality, the pills actually don’t have any taste or flavor, which is probably best, all things considered. In addition, other studies of FMT pills have used fewer doses, so future treatments may not necessarily require quite so many pills.

As fecal transplants continue to show promise for treating harmful gut diseases, the concept of a poop-filled pill may begin to seem less icky and more routine. After all, we take probiotics to keep our guts happy and healthy. Why not go directly to the source?

CATEGORIZED UNDER: Health & Medicine, top posts

Measuring Vital Signs Just Got Easier

By Nathaniel Scharping | November 27, 2017 3:11 pm
(Credit: toysf400/Shutterstock)

(Credit: toysf400/Shutterstock)

If you’ve ever spent any time at a hospital, you know what it’s like to be under constant supervision. Sensors and monitors keep track of your most basic bodily functions day and night, giving doctors and nurses to-the-second information on how you’re doing. All that supervision comes with wires and sensors taped and stuck all over a patient’s body, though, which is annoying and can throw off some readings.

Now, two Cornell University researchers say they’ve devised a way to monitor vital signs that doesn’t require skin contact. Their technique relies on small radio frequency identification (RFID) sensors, the same technology that’s in key fobs, that can pick up heartbeats, chest movements and even blood pressures, and can keep track of multiple patients at once. The technology could be useful in hospitals where round-the-clock supervision is key. Read More

CATEGORIZED UNDER: Health & Medicine, Technology
MORE ABOUT: medical technology

Watch an Epic Duet Between Human and Robot

By Lauren Sigfusson | November 27, 2017 3:02 pm
robot-dance-human-kuka-huang-yi

Huang Yi rehearses with robot ‘KUKA’ at 3-Legged Dog. (Credit: Jacob Blickenstaff)

Dance can be defined as “a series of movements that match the speed and rhythm of a piece of music.” Notice it doesn’t say dance is specific to humans — and this performance proves it. A Taiwanese choreographer, dancer and inventor named Huang Yi programmed and created a robot to dance with.

This isn’t the first time machines and humans have shared the dance floor — Cirque du Soleil choreographed a magical sequence filled with twirling, flying drones that looked like lampshades. But something’s different about Huang’s and his robot’s (called KUKA) performance. It evokes a sense of intimacy, of struggle, of reliance. Read More

CATEGORIZED UNDER: Technology, top posts
MORE ABOUT: robots

Turtles Survive Frigid Hibernations By Breathing Through Their Butts

By Jacqueline Litzgus, Laurentian University | November 22, 2017 1:58 pm
Turtles can’t head south for the winter, so they hibernate in rivers, lakes and ponds. (F_studio)

Turtles can’t head south for the winter, so they hibernate in rivers, lakes and ponds. (F_studio)

To breathe or not to breathe, that is the question.

What would happen if you were submerged in a pond where the water temperature hovered just above freezing and the surface was capped by a lid of ice for 100 days?

Well, obviously you’d die.

And that’s because you’re not as cool as a turtle. And by cool I don’t just mean amazing, I mean literally cool, as in cold. Plus, you can’t breathe through your butt.

But turtles can, which is just one of the many reasons that turtles are truly awesome.

Cold Weather Slow Down

As an ectotherm — an animal that relies on an external source of heat — a turtle’s body temperature tracks that of its environment. If the pond water is 1℃, so is the turtle’s body.

But turtles have lungs and they breathe air. So, how is it possible for them to survive in a frigid pond with a lid of ice that prevents them from coming up for air? The answer lies in the relationship between body temperature and metabolism.

A cold turtle in cold water has a slow metabolism. The colder it gets, the slower its metabolism, which translates into lower energy and oxygen demands.

When turtles hibernate, they rely on stored energy and uptake oxygen from the pond water by moving it across body surfaces that are flush with blood vessels. In this way, they can get enough oxygen to support their minimal needs without using their lungs. Turtles have one area that is especially well vascularized — their butts.

See, I wasn’t kidding, turtles really can breathe through their butts. (The technical term is cloacal respiration.)

Not Frozen, Just Cold

We are not turtles. We are endotherms — expensive metabolic heat furnaces — that need to constantly fuel our bodies with food to generate body heat and maintain a constant temperature to stay alive and well.

When it’s cold out, we pile on clothes to trap metabolic heat and stay warm. We could never pick up enough oxygen across our vascularized surfaces, other than our lungs, to supply the high demand of our metabolic furnaces.

Turtles will bask in the sun to warm up and ease their crampy muscles. (Credit: Patrick Moldowan)

For humans, a change in body temperature is a sign of illness, that something is wrong. When a turtle’s body temperature changes, it’s simply because the environment has become warmer or colder.

But even ectotherms have their limits. With very few exceptions (e.g., box turtles), adult turtles cannot survive freezing temperatures; they cannot survive having ice crystals in their bodies. This is why freshwater turtles hibernate in water, where their body temperatures remain relatively stable and will not go below freezing.

Water acts as a temperature buffer; it has a high specific heat, which means it takes a lot of energy to change water temperature. Pond water temperatures remain quite stable over the winter and an ectotherm sitting in that water will have a similarly stable body temperature. Air, on the other hand, has a low specific heat so its temperature fluctuates, and gets too cold for turtle survival.

Crampy Muscles

An ice-covered pond presents two problems for turtles: they can’t surface to take a breath, and little new oxygen gets into the water. On top of that, there are other critters in the pond consuming the oxygen that was produced by aquatic plants during the summer.

Over the winter, as the oxygen is used up, the pond becomes hypoxic (low oxygen content) or anoxic (depleted of oxygen). Some turtles can handle water with low oxygen content — others cannot.

Snapping turtles and painted turtles tolerate this stressful situation by switching their metabolism to one that doesn’t require oxygen. This ability is amazing, but can be dangerous, even lethal, if it goes on for too long, because acids build up in their tissues as a result of this metabolic switch.

But how long is “too long”? Both snapping turtles and painted turtles can survive forced submergence at cold water temperatures in the lab for well over 100 days. Painted turtles are the kings of anoxia-tolerance. They mobilize calcium from their shells to neutralize the acid, in much the same way we take calcium-containing antacids for heartburn.

In the spring, when anaerobic turtles emerge from hibernation, they are basically one big muscle cramp. It’s like when you go for a hard run — your body switches to anaerobic metabolism, lactic acid builds up and you get a cramp. The turtles are desperate to bask in the sun to increase their body temperature, to fire up their metabolism and eliminate these acidic by-products.

And it’s hard to move when they’re that crampy, making them vulnerable to predators and other hazards. Spring emergence can be a dangerous time for these lethargic turtles.

Cold Weather Turtle Tracking

Field biologists tend to do their research during the spring and summer, when animals are most active. But in Ontario, where the winters are long, many turtle species are inactive for half of their lives.

Understanding what they do and need during winter is essential to their conservation and habitat protection, especially given that two-thirds of turtle species are at risk of extinction.

X marks the spot. Former graduate student Bill Greaves tracks turtles during a cold Ontario winter. (Credit: Author provided)

My research group has monitored several species of freshwater turtles during their hibernation. We attach tiny devices to the turtles’ shells that measure temperature and allow us to follow them under the ice.

We’ve found that all species choose to hibernate in wetland locations that hover just above freezing, that they move around under the ice, hibernate in groups and return to the same places winter after winter.

Despite all this work, we still know so little about this part of turtles’ lives.

So, I do what any committed biologist would do: I send my students out to do field research at -25℃. We are not restricted to fair-weather biology here.

The ConversationBesides, there is unparalleled beauty in a Canadian winter landscape, especially when you envision all of those awesome turtles beneath the ice, breathing through their butts.

 

[This article was originally published on The Conversation. Read the original article.]

CATEGORIZED UNDER: Living World
MORE ABOUT: animals

How Breathing Links Mind and Body

By Leah Froats | November 22, 2017 1:12 pm
(Credit: Billion Photos/Shutterstock)

(Credit: Billion Photos/Shutterstock)

Whether it’s regulating a burst of anger or calming down a bout of anxiety, taking a deep breath can have a potent effect.

There are compelling hints that controlled breathing can improve overall physical wellbeing, but the neurophysiology — the link between our minds and bodies — of controlled breathing hasn’t been very extensively researched. A new study from researchers at Northwestern University and the Hofstra Northwell School of Medicine begins to delve into the topic by attempting to separate the mechanisms that govern controlled and automatic breathing in the brain. Read More

CATEGORIZED UNDER: Health & Medicine, Mind & Brain

Storms Generate Thunder, Lightning and…Antimatter?

By Charles Choi | November 22, 2017 12:00 pm
lightning

(Credit: Shutterstock)

In the skies above Japan, scientists have detected lightning triggering nuclear reactions. These new findings are clear evidence that thunderstorms are a natural source of radioactive isotopes on Earth.

Thunderstorms are natural particle accelerators, capable of hurling electrons outward at nearly the speed of light. When these electrons strike atoms, they can generate gamma rays, the highest-energy form of light. Read More

CATEGORIZED UNDER: Space & Physics, top posts

PTSD: An Overlooked Consequence of a Cancer Diagnosis

By Nathaniel Scharping | November 21, 2017 4:13 pm
(Credit: Shutterstock)

(Credit: Shutterstock)

Roughly one in five cancer patients struggle with post traumatic stress disorder (PTSD) in the aftermath of diagnosis and treatment.

A recent study from Malaysia indicates that PTSD is a fairly common result of the long and difficult process of living with and treating cancer. Though most commonly associated with soldiers returning from war, PTSD can result from many different forms of trauma. The disorder can sometimes go unnoticed, or be misdiagnosed, causing those suffering to endure psychological distress that can lead to suicide in some situations. Read More

CATEGORIZED UNDER: Health & Medicine, top posts
MORE ABOUT: cancer, mental health, ptsd
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