Tuesday, March 31, 2015
Unbelievably Cute Mammal With Teddy Bear Face Rediscovered
By Carrie Arnold, National Geographic
You could call it one of the world's longest games of hide and seek.
For more than 20 years, the Ili pika (Ochotona iliensis), a type of tiny, mountain-dwelling mammal with a teddy bear face, had eluded scientists in the Tianshan Mountains (map) of northwestern China.
People have seen the furry critter only a handful of times since it was discovered by accident in 1983. In fact, people have spotted only 29 live individuals, and little is known about the animal's ecology and behavior. (Also see "Newly Discovered Carnivore Looks Like Teddy Bear.")
Then, in summer 2014, researchers rediscovered the pika.
Weidong Li, the species' original discoverer and a scientist at the Xinjiang Institute for Ecology and Geography, had gathered a group of volunteers in the Tianshan Mountains for some pika searching. At noon one day, as they were setting up camera traps, the team spotted their prize.
A curious pika emerged from a gap in the cliff face, and Li snapped a few photos (including the one above).
"They found it hiding behind a rock, and they realized they had found the pika. They were very excited," said Tatsuya Shin, a naturalist in China who works with the pika's discoverers.
Mountain High
In 1983, the Chinese government sent Li to the mountainous Xinjiang Province to study natural resources and infectious diseases. As Li explored a valley by Jilimalale Mountain, he saw a small, gray head sticking out from a crack in the rock. As he edged closer, Li got a look at its whole body.
The animal was about 8 inches (20 centimeters) long, with large ears and several small brown spots in its gray fur. Li wasn't familiar with the species, nor were nearby herdsmen. Li caught a specimen and sent it to a scientist at the Chinese Academy of Sciences, who said he believed the pika was a new species.
Although Li couldn't find any more pikas on a second trip to the area in December 1983, a third trip in 1985 was more successful, and the additional specimens allowed academy researchers to confirm that the Ili pika was new to science.
Tiny and in Trouble
Like other species of pika found in North America, the Ili pika lives at high elevations—between 9,200 and 13,450 feet (2,800 to 4,100 meters)—and subsists mainly on grasses, herbs, and other mountain plants.
Like other high-dwelling creatures, the pika is sensitive to changes in its environment. A 1990s estimate put its population at about 2,000 individuals, and it's believed to be decreasing in number, according to the International Union for Conservation of Nature.
Grazing pressure from livestock and air pollution have likely contributed to the decline in the Ili pika, which IUCN lists as vulnerable to extinction. China considers the species endangered. (Related: "Tiny, Rabbit-Like Animals Eating 'Paper' to Survive Global Warming.")
Even so, there are no concerted efforts under way to help the Ili pika. Li said he hopes to change that, and use the rediscovery of the animal to create conservation areas for the species.
How could anyone turn down a face like that?
Monday, March 30, 2015
Energy Drinks Raise Blood Pressure, Study Finds
by Christopher Wanjek
Energy drinks might give you some pep — but they might also be priming you for heart problems, a new study finds.
Researchers found that energy drinks can raise blood pressure to potentially unhealthy levels. The effect was far more prominent in young adults who did not consume caffeine regularly, according to the study, presented March 14 at an American College of Cardiology meeting in San Diego.
In this study, the research team — led by Dr. Anna Svatikova, a cardiovascular-diseases fellow at the Mayo Clinic in Rochester, Minnesota — gave a can of a commercially available energy drink to 25 healthy volunteers, whose ages ranged from 19 to 40. On a different day, the participants drank the same amount of a placebo drink. The researchers measured the participants' heart rate and blood pressure before and after the drinks.
The participants experienced a more marked rise in blood pressure after consuming the energy drink than after drinking the placebo, according to the findings. The participants' average systolic blood pressure (the top number in a blood pressure reading) increased by 3 percent more after they drank an energy drink, compared with after they drank the placebo drink. [5 Health Problems Linked to Energy Drinks]
The effect was most dramatic in people who did not typically consume more than a small cup of coffee or other caffeinated drink daily. In this so-called "caffeine-naive" group, the blood pressure increase was twice as high as the increase seen in the people who drank at least the equivalent of a cup of coffee on a daily basis, the researchers said in a statement.
Even a small increase in blood pressure can have deadly consequences, depending on your age and resting blood pressure, said Sachin Shah, an associate professor of pharmacy at the University of the Pacific in Stockton, California, who was not involved in the study.
"An acute, moderate increase in blood pressure is typically not a cause of worry in healthy subjects," said Shah, who has done research on the effects of energy drinks. However, in older people or those with hypertension, a moderate increase may be a cause for concern, he said.
At a population level, an increase of three or four points on a systolic blood pressure reading could mean a significant increase in deaths from stroke, he told Live Science.
Scientists do not know whether it is the caffeine, taurine or other ingredients found in energy drinks — or a combination of ingredients — that can adversely affect the heart.
In a separate study, presented last year at an American Heart Association meeting by Maj. Emily Fletcher of the David Grant Air Force Medical Center, healthy volunteers experienced a greater increase in blood pressure after they consumed an energy drink compared to after they drank a coffee drink that had an equal amount of caffeine. This result, Fletcher said, suggests that ingredients in the energy drink other than caffeine were conspiring to raise blood pressure.
According to the Mayo Clinic, consuming up to 400 milligrams of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks.
Previous studies have associated the consumption of energy drinks with poor memory and learning, anxiety, hallucinations, abnormal heart rhythm, substance abuse, and risk-taking behaviors. A study published in the journal Pediatrics in 2011 found that children, in particular, are at high risk of cardiac abnormalities from consuming energy drinks because of their smaller body size.
Follow Christopher Wanjek @wanjek for daily tweets on health and science with a humorous edge. Wanjek is the author of "Food at Work" and "Bad Medicine." His column, Bad Medicine, appears regularly on Live Science.
Sunday, March 29, 2015
Mystery of the 'Vampire Crabs' Solved
by Agata Blaszczak-Boxe
The mystery of the origin of two strange-looking species of "vampire crabs" is finally solved. The crabs come from the island of Java in Indonesia, according to the scientists who officially describe the species in a new report.
Vampire crabs owe their name to their spooky appearance, as they have bright-yellow eyes contrasting sharply with purple or orange abdomens.
People in the aquarium trade have known of the two crab species described in the report for at least a decade, said Peter Ng, a biology professor at the National University of Singapore and an author of the report. Ng said he saw the crabs for the first time in aquaria in Singapore, where the crustaceans were being sold as pets.
The problem for scientists was that it was not clear where the crabs originally came from, which made it difficult for researchers to actually name and describe the traits of the species in the wild. [The 7 Weirdest Glow-in-the-Dark Creatures]
"For a species to be formally and properly described and named, its provenance should be known," Ng told Live Science. "Of course, it is perfectly legal to name a species without knowing where it comes from, but that would be bad science and irresponsible."
Crab dealers have pointed to a number of possible places of origin for the crabs, from Java to Krakatoa, Borneo, Sulawesi and even New Guinea. But all of those sites were suspicious, Ng said.
With a good deal of detective work, study coauthor Christian Lukhaup, a German carcinologist (crab expert), traced the crabs' origins from dealers in Germany all the way back to Java, Ng said. Lukhaup persuaded businessmen and traders to connect him to the people in Java who were actually collecting the crab. These collectors then passed specimens of the animals on to the researchers.
The two new species have been named Geosesarma dennerle and Geosesarma hagen. There are now 53 species of Geosesarma genus known to science, said Ng, who himself has named 20 of the species. He said he currently has another half a dozen or so newly collected Geosesarma species from Southeast Asia in his lab, and these species still need to be named and described.
"So there are more to come as we explore and discover them," he said.
But the two newly described species may already be under threat from potential over-collecting for the aquarium trade, the researchers said. "Any species that is over-exploited — be it for food, or as a pet — stands [to be] threatened," Ng said. "More so for a small freshwater crab like this, which has a relatively restricted range."
The researchers said they are also worried about "the potential loss of [the crabs'] pristine habitat," Ng said. If this habitat becomes polluted or changed by human activity, the crabs' populations may collapse, he said.
"The nightmare for biodiversity researchers is that we are always working against the clock — too many species to discover and too little time," Ng added.
The study was published online Jan. 16 in the journal Raffles Bulletin of Zoology.
Saturday, March 28, 2015
Humans Butchered Elephants 500,000 Years Ago, Ancient Tool Suggests
by Tia Ghose
Stone tools that are half a million years old have been unearthed in Israel — and they still have traces of elephant fat clinging to them.
The new discovery shows that ancient humans used tools to process and butcher large animals, researchers say.
Though anthropologists had strongly suspected that early humans used tools to break down a carcass for its muscle, fat and marrow, "there was no smoking gun to show that the stone tools were, indeed, used for these kinds of tasks," said study co-author Ran Barkai, a professor of archaeology at Tel Aviv University in Israel.
Ancient toolmaking
Between 1.8 million and 1.5 million years ago, early humans underwent two dramatic changes. First, the brains of Homo erectus got much bigger. Then, soon after, the ancient hominins stopped using a toolmaking method in which they'd bash hard rocks against other stones that could form an edge. Instead, these early humans began to use a more sophisticated toolmaking method known as Acheulean technology, in which the two faces of hand axes or scrapers are flaked off to form a blade, archaeological evidence shows.
Many scientists say these two developments are linked; the greater caloric needs of brainy humans would have required them to hunt or scavenge animals, and then butcher them to get at their meat and fat — and that required more advanced toolmaking technology, scientists have hypothesized.
Early humans used Acheulean technology of roughly the same size and shape for more than a million years, and very similar-looking tools have been found throughout the world. Archaeologists often find the tools at sites alongside animal bones, such as mammoth and elephant bones discovered at Paleolithic sites in the Levant in southwestern Asia, with cut marks and signs of breakage to extract marrow. But in these instances, the evidence that the humans used the tools to butcher animals was still circumstantial.
Well-preserved site
In 2004, Barkai and his colleagues were excavating a quarry in Revadim, Israel, that held tens of thousands of well-preserved flint tools and thousands of animal bones from species such as wild aurochs, goats, gazelles and deer. But the site also contained bones from the straight-tusked elephant, a now-extinct pachyderm similar to the modern-day Asian elephant. The newest remains at the site were at least 300,000 to 500,000 years old.
In one spot, the team discovered three small hand axes and scrapers not far from a neatly cut elephant tusk. A chemical analysis of a mysterious residue on the hand axes revealed it was fat from a straight-tusked elephant.
The team also analyzed the wear on the surfaces of the tools, and even created replicas of the blades, to determine how they would have been used. Based on those recreations, the team determined that the hand ax made an excellent multipurpose tool that would have been good for cutting bones, sinew and hide. The scraper, with its slimmer and more fragile blade, was ideal for separating the fur, fat and muscle, they found.
Perfect tools
The new discovery supports the notion that tool development was a key factor in humans' ability to eat more meat at this point in human history.
"In order to be able to use animal resources, they needed to have tools in order to cut and butcher," Barkai told Live Science.
The results may also help to explain why tools didn't change for such a long period: They didn't need to, Barkai said.
"These tools enabled them to survive and thrive for over 1 million years," Barkai said. "They fit the needs of these hominins."
Friday, March 27, 2015
Can You Really Freshen Up Women's 'Aging' Eggs?
by Tia Ghose
Can you teach an old egg new tricks?
One fertility treatment company claims it can, by rejuvenating women's aging eggs. The company, called OvaScience, says its method aims to improve the health of an egg's mitochondria, which are the tiny powerhouses that give cells the energy to divide and grow.
But experts advise caution over those claims. Although some early evidence suggests aging mitochondria could reduce a woman's fertility, expert say, there are no studies that prove the new method will work. In addition, the company isn't forthcoming with details of its process.
"They're quite private and secretive about what they're doing," said Dr. Aimee Eyvazzadeh, a San Francisco Bay Area ob-gyn and fertility specialist who has no affiliation to OvaScience. "If you were to call as a consumer, they wouldn't tell you anything." [Future of Fertility: 7 Ways Baby-Making Could Change]
What's more, the Food and Drug Administration (FDA) hasn't approved the method that the company says it uses, so the treatment is not available in the United States, just in a few other countries.
Fertility and age
The method is based on the idea that time takes its toll on women's eggs. When a woman is born, she has all the follicles, or immature eggs, she will ever have. At birth, baby girls have millions of follicles in their ovaries, but throughout a woman's life, the follicles die, said Kateryna Makova, a genomicist at Pennsylvania State University in State College, who is not associated with Ova Science.
Once a girl reaches puberty, she begins to ovulate. During ovulation, hormonal spikes spur one egg at a time to mature, after which it is released from the ovary into the fallopian tubes. But by the time a girl starts menstruating, she may have only a few hundred thousand eggs left, and a woman at menopause has almost no follicles left.
Though follicles in the ovary are somewhat protected from damage, various factors can cause genetic mutations that rack up over time, Makova said. Mutations can result from the passage of time, ultraviolet radiation and even inflammation due to illness. These genetic changes occur not only in the nuclear DNA, but also in the DNA found inside the mitochondria.
The older women get, the less likely they are to ovulate, and the eggs they do release are less likely to divide properly and develop into a healthy baby.
"Fertility peaks before age 30," Eyvazzadeh told Live Science. "Very few women have a chance of pregnancy in our 40s."
Refurbished eggs?
Some very early evidence suggests that mitochondria, which are tiny organelles inside the cytoplasm of the egg cell, do change with age. As a result, these cellular power plants may no longer have the right machinery to fuel cell division after fertilization, Eyvazzadeh said.
For instance, a 2014 study by Makova and her colleagues found that children born to older mothers have more mutations in their mitochondria, although she noted that the study didn't directly show that older oocytes have more mitochondrial mutations.
So the treatment has at least some logical basis, Makova said.
"In theory, this might be helpful," she told Live Science. "But how to do this in practice, and how to do this right in practice is difficult to address."
OvaScience claims it has identified a pool of "precursor cells," essentially a kind of stem cell, that can be extracted from a woman's ovary and inserted into her eggs to improve the condition of the mitochondria.
Each oocyte contains many copies of mitochondria, and mitochondria have just 37 genes. So it's possible that during fertility treatment or IVF, some immature eggs in the ovary could be tested to see if they contain healthy mitochondrial DNA free of harmful mutations. Implanting cells from those immature follicles, with their healthy mitochondria, could then provide a power boost to rejuvenate aging eggs, Makova said. [7 Ways Pregnant Women Affect Babies]
But there are still problems with the idea; for example, the follicles in the ovary are unlikely to be in any better condition than those in the old eggs that mature, Makova said.
"They are also not young," Makova said.
In addition, Eyvazzadeh hasn't seen any published studies proving the existence of the precursor cells the company claims to use.
And even if the mitochondrial DNA could be improved, it's likely there are other factors that make aging eggs a problem, Eyvazzadeh said.
But if the procedure does work, it would be extremely exciting news, Eyvazzadeh said.
"They've said they've discovered this precursor cell in humans and this cell can somehow mature into healthy, young fertilizable eggs? Well, that's awesome, let me at that cell!" Eyvazzadeh said.
Thursday, March 26, 2015
Weird 'Water Tongue' Lets Fish Feed on Land
by Charles Q. Choi, Live Science Contributor
A fish that uses water as a sort of tongue to feed on land could shed light on how animals with backbones first invaded land, researchers say.
One of the most pivotal moments in evolution occurred when a few pioneering fish left the waterabout 350 million to 400 million years ago. These fish evolved into the first tetrapods (four-legged land animals), which ultimately gave rise to amphibians, reptiles, birds and mammals.
To figure out how ancient animals made this shift to land, scientists typically investigate how the limbs of the first tetrapods evolved over time. However, biomechanistKrijn Michel at the University of Antwerp in Belgium and his colleagues suggest that investigating how early tetrapods learned to eat on land is equally important to understanding this key point in evolution.
In the water, fish generate suction with their mouths to help draw in food with the help of a neck bone known as the hyoid. On land, sucking in air to swallow food proved impractical, so tetrapods instead evolved tongues supported by the hyoid that help guide food down their throats. However, much remains unknown about how tetrapod hyoids and tongues evolved.
To learn more about the evolution of tetrapod feeding, the scientists investigated modern amphibious fish known as mudskippers that dine on land. Mysteriously, these fish emerge onto land with their mouths filled with water.
Now, Michel and his colleagues have found that mudskippers use their mouthfuls of water "like a tongue to capture and swallow food on land, a finding that may give us a glimpse into how the very first land vertebrates evolved from fish 400 million to 350 million years ago," Michel told Live Science.
The researchers experimented with five mudskippers from Nigeria, using high-speed video cameras and X-ray scanners to record the fish feeding on shrimp.
Results showed that the mudskippers fed by first exuding water from their mouths and then quickly sucking it back up once it submerged the food. Essentially, the water acted like a tongue.
When using this "hydrodynamic tongue," the mudskippers moved their hyoids upward, "more or less the opposite of what fish do to feed underwater," Michel said. However, the mudskipper hyoids behaved much like how those of primitive tetrapods such as newts do during feeding.
The researchers suggest that early tetrapods may have used hydrodynamic tongues when first moving onto land, and evolved fleshy tongues later to gain further independence from the water.
Michel and his colleaguesdetailed their findings online March 18 in the journal Proceedings of the Royal Society B.
Wednesday, March 25, 2015
Ancient Egyptian Mummy Found With Brain, No Heart
An ancient Egyptian mummy found with an intact brain, but no heart, has a plaque on her abdomen that may have been intended to ritually heal her, say a team of researchers who examined the female body with CT scans.
The woman probably lived around 1,700 years ago, at a time when Egypt was under Roman rule and Christianity was spreading, according to radiocarbon dating. Her name is unknown and she died between age 30 and 50. Like many Egyptians, she had terrible dental problems and had lost many of her teeth.
The use of mummification was in decline as Roman culture and Christianity took hold in the country. But this woman and her family, apparently strong in their traditional Egyptian beliefs, insisted on having the procedure done. [See Images of the Ancient Egyptian Mummy & Weird Plaque]
To remove her organs, the scans show, the embalmers created a hole through her perineum and removed her intestines, stomach, liver and even her heart. Her brain, however, was left intact. Spices and lichen were spread over her head and abdomen, and she was wrapped and presumably put in a coffin; her final resting place was likely near Luxor, 19th century records say.
Before the embalmers were finished they filled the hole in the perineum with linen and resin. They also put two thin plaques similar to cartonnage (a plastered material) on her skin above her sternum and abdomen, something that may have been intended to ritually heal the damage the embalmers had done and act as a replacement, of sorts, for her removed heart.
"The power of current medical imaging technologies to provide evidence of change in ancient Egyptian mortuary ritual cannot be understated," writes the research team in an article to be published in the "Yearbook of Mummy Studies." While the technology is powerful it does have some limits. The presence of spices and lichen on the head were first found in the 19th century when the head was unwrapped. The CT scans revealed that they are likely also located on the mummy's abdomen, a determination aided by this unwrapping.
An ancient Egyptian mummy found with an intact brain, but no heart, has a plaque on her abdomen that may have been intended to ritually heal her, say a team of researchers who examined the female body with CT scans.
The woman probably lived around 1,700 years ago, at a time when Egypt was under Roman rule and Christianity was spreading, according to radiocarbon dating. Her name is unknown and she died between age 30 and 50. Like many Egyptians, she had terrible dental problems and had lost many of her teeth.
The use of mummification was in decline as Roman culture and Christianity took hold in the country. But this woman and her family, apparently strong in their traditional Egyptian beliefs, insisted on having the procedure done. [See Images of the Ancient Egyptian Mummy & Weird Plaque]
To remove her organs, the scans show, the embalmers created a hole through her perineum and removed her intestines, stomach, liver and even her heart. Her brain, however, was left intact. Spices and lichen were spread over her head and abdomen, and she was wrapped and presumably put in a coffin; her final resting place was likely near Luxor, 19th century records say.
Before the embalmers were finished they filled the hole in the perineum with linen and resin. They also put two thin plaques similar to cartonnage (a plastered material) on her skin above her sternum and abdomen, something that may have been intended to ritually heal the damage the embalmers had done and act as a replacement, of sorts, for her removed heart.
"The power of current medical imaging technologies to provide evidence of change in ancient Egyptian mortuary ritual cannot be understated," writes the research team in an article to be published in the "Yearbook of Mummy Studies." While the technology is powerful it does have some limits. The presence of spices and lichen on the head were first found in the 19th century when the head was unwrapped. The CT scans revealed that they are likely also located on the mummy's abdomen, a determination aided by this unwrapping.
Tuesday, March 24, 2015
Siats meekerorum WAS BIGGER THAN THE T REX
Before T. rex, This dinosaur was king: Researchers have discovered another top dino that lived before Tyrannosaurus rex. About 98 million years ago — 31 million years before tyrannosaurs — there was Siats meekerorum, whose bones were found in Utah. The onetime top predator walked on two legs and may have weighed four tons.
Monday, March 23, 2015
DEPRESSION AND YOU
Depressed? Tackling your insomnia first could help: That depressed people often suffer from insomnia isn't news. This part is: New research suggests that treating the insomnia first with talk therapy might ease the symptoms of depression. If the research holds up, it could be the biggest milestone for depression treatment since Prozac, says one report.
Sunday, March 22, 2015
An Incredible Discovery
Ancient ocean found beneath Chesapeake Bay: The remains of a salty ocean ancient enough for dinosaurs to have drowned in it have been found deep in the sediment under the Chesapeake Bay. The seawater — believed to be 100 to 150 million years old — was isolated, trapped a half-mile underground, and preserved with the help of an asteroid. The find suggests that the oceans of yore were twice as salty as today's.
Saturday, March 21, 2015
One of most incredible discoveries ever
Egyptian mummies got meat dishes for eternity: Those ancient Egyptian mummifiers thought of everything, it seems. Even eternal snacks. Scientists have for the first time analyzed what they call "meat mummies," the cuts of meat stashed alongside the mummies themselves. One aspect of the preservation technique proved especially surprising.
Friday, March 20, 2015
Neutrinos discovery at the South Pole
Neutrinos discovery may mean 'new era for astronomy': Scientists at the South Pole have found visitors from outside our solar system, but instead of little green men, think "ghostly neutrino particles." Suffice to say that physicists are very excited — think "new era of astronomy" excited — because some of the universe's secrets might be in danger. One scientist thinks this is a Nobel prize in the making.
Thursday, March 19, 2015
Should Marijuana Be a Medical Option?
In 1970, the US Congress placed marijuana in Schedule I of the Controlled Substances Act because they considered it to have "no accepted medical use." Since then, 23 of 50 US states and DC have legalized the medical use of marijuana.
Proponents of medical marijuana argue that it can be a safe and effective treatment for the symptoms of cancer, AIDS, multiple sclerosis, pain, glaucoma, epilepsy, and other conditions. They cite dozens of peer-reviewed studies, prominent medical organizations, major government reports, and the use of marijuana as medicine throughout world history.
Opponents of medical marijuana argue that it is too dangerous to use, lacks FDA-approval, and that various legal drugs make marijuana use unnecessary. They say marijuana is addictive, leads to harder drug use, interferes with fertility, impairs driving ability, and injures the lungs, immune system, and brain. They say that medical marijuana is a front for drug legalization and recreational use.
Tuesday, March 17, 2015
Monday, March 16, 2015
ANNA ATKINS
Anna Atkins was an English botanist and photographer. She is often considered the first person to publish a book illustrated with photographic images. Some sources claim that she was the first woman to create a photograph.
Wednesday, March 11, 2015
SERA QUE CONOCES A ESTA MUJER
Solicitamos tu ayuda... ésta mujer de aproximadamente 30 años de edad, se encuentra en calidad de desconocida en la cama 112 de terapia intensiva del Hospital General, fue localizada en Rosamorada severamente golpeada y trasladada a Tepic, con traumatismo craneoencefálico severo, fractura de pelvis y golpes en todo su cuerpo... si la identificas o conoces a alguno de sus familiares, por favor comunícate a Derechos Humanos al Tel. 213-89-86 o lada sin costo 01 800 503-77-55.
Las imágenes no son agradables, pero por favor comparte, alguno de tus contactos podría ayudar a identificarla... gracias.
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