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Did our paleo ancestors sleep better than us?

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San hunter-gatherers from Namibia sleep about 6.4 hours per night on average. Photo by Josh Davimes

San hunter-gatherers from Namibia sleep about 6.4 hours per night on average. Photo by Josh Davimes

In modern society, we leave the lights on and stay up late. We watch Netflix or scroll news stories on our smartphones until the wee hours of the morning.

We blame societal expectations and technology for these sleep habits, but new research suggests keeping awake long past sundown might just be human nature.

A sleep tracker study of three hunter-gatherer populations shows that ‘primitive’ communities sleep as much or even less than modern societies. The findings detail a paleo lifestyle that comes with fewer sleep disorders, but also point to a way to trigger sleep outside of just turning off the lights.

To make these insights, UCLA neuroscientist Jerome Siegel and his colleagues visited three hunter-gatherer populations: the Hadza of Tanzania, the San of Namibia, and the Tsimane of Bolivia.

“Has sleep decreased because of electronics and electricity?” said Siegel, who directs UCLA’s Center For Sleep Research. “There’s no way to go back before artificial light, to the mid-1800s,” he said, but certain hunter-gatherer societies maintain a pre-industrial lifestyle that can give scientists insight into natural sleep patterns.

Location of recording sites (l[caption id=

Location of study sites. Photo by Yetish et al., 2015, Current Biology

The researchers monitored 94 people among these groups by handing out wrist devices that track physical activity but also light levels. There have been thousands of studies using these devices to measure sleep, and they’ve been found to be quite accurate, Siegel said. In this study, the gadgets worked around the clock to log over 1,165 days of data.

Rather than hit the pillow when night fell, these outdoors communities stayed awake up to four hours after sunset. For comparison, the sun will set in Washington D.C. today around 6:30 pm, so these folks would pass out just after most local TV news programs.

But then, instead of sleeping late, these communities often climbed out of bed before sunrise. On average, the three groups only slept between 5.7 and 7.1 hours per night. (Note: The National Sleep Foundation in the United States recommends 7-9 hours for adults.)

“Their sleep is actually on the low end of what’s been recorded in our modern society. There’s been speculation that humans basically used to sleep when it got dark, which would mean they’d sleep 10, 11, even 12 hours. It turns out that that’s not the case,” Siegel said.

But they can nap whenever they want, right?

Nope. They rarely napped. On cold winter days, the team caught napping activity in only seven percent of afternoon recordings among the San. During the warmer summers, nap frequency increased to 22 percent of the days.

This observation was one of many suggesting a seasonal change in sleeping behavior among these hunter-gatherer groups. This pattern led Siegel’s team to conclude that temperature, rather than light, plays a defining role in the sleep-wake cycles of these three groups.

So should you throw off your comforter at night and live the “paleo” way? Maybe.

According to in-person interviews, the San didn’t seem to suffer from sleep disorders, like insomnia. Their fitness levels could be a factor, for instance, the Hazda make long treks to hunt food by bow and arrow. None of the participants in this study had a body mass index over 30, and obesity has been tied to poorer sleep quality.

Alternatively, the differences between western and paleo sleep patterns might be due to culture and societal demands. We may nap and sleep late because of the high-energetic demands of busy work and school schedules. Or central heating and warm apparel in Western culture, like light exposure, might keep people from falling asleep.

“It depends on the demands of that particular society, their climate, what time of year it is,” said Max Hirshkowitz, chair of the National Sleep Foundation. “Actual physiological sleep time probably hasn’t changed that much, if at all [historically]. What has changed over the years is the amount of time people allocate to get their sleep.”

Yet it is apparent that sleep patterns in western culture are often off-kilter for both teens and adults.

“It’s an uphill battle, because for many, many years people have been encouraged to sleep less so they could spend more time doing their other things,” Hirshkowitz said. “Whether it’s by choice or whether or not they’re being urged, or even coerced in that direction, this is a culture. We need to change that culture.”

Editor’s note: Are we more sleep deprived than our ancestors? On tonight’s PBS NewsHour, Hari Sreenivasan reports on questions raised by new sleep research.

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These hunter-gatherer tribes sleep less than you, and sleep better

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Young man sleeping in bed

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HARI SREENIVASAN: But, first, just how much sleep do you really need? There’s been plenty of concern, as people spend more time looking at their screens ever later into the night.

Previous research has shown that a lack of sleep is associated with a series of problems, ranging from lack of concentration to health effects like obesity and heart disease.

But a new study out today finds seven or eight hours a night may not be as essential as we think.

I went to California to learn more.

They are among the last hunter-gatherers in the world, the Hadza of Northern Tanzania, the San of Namibia’s Kalahari Desert, and in the Andean foothills of Bolivia the Chimane.

By studying the sleep habits of these three groups, who still live the way humans have for thousands of years, a team of scientists led by UCLA’s Jerry Siegel is challenging conventional wisdom about how much sleep we need.

JERRY SIEGEL, Director, UCLA Center for Sleep Research: It’s absolutely incorrect to think that the more you sleep, the healthier you’re going to be.

HARI SREENIVASAN: The study, reported today in the journal “Current Biology” says we in the industrialized world sleep as much as our ancestors did.

JERRY SIEGEL: There’s been speculation that humans basically used to sleep when it got dark, which would mean they’d sleep 10, 11, even 12 hours. But it turns out that’s not the case. These groups sleep five, six, seven hours. None of them average over eight hours of sleep.

HARI SREENIVASAN: Just like us, when the sun sets, these people do not go right to sleep.

JERRY SIEGEL: There’s a thin yellow line here that indicates the light level, and you can see also that they remain awake.

HARI SREENIVASAN: In fact, regardless of what time they go to bed, all three groups, on different parts of the planet, wake up exactly when one very specific thing happens. And, no, it’s not the sunrise.

JERRY SIEGEL: They’re sleeping as the temperature falls, and they seem to quite consistently wake up at the lowest point of temperature in the day. So, when the temperature stops falling, that’s when they wake up.

There’s been a lot of emphasis on light and the effects of light, and there’s no question that light affects sleep. But light may have been connected to sleep largely because of its connection to temperature.

HARI SREENIVASAN: Temperature swings are a thing of the past. Now we just have to turn a dial.

The connections between sleep and many things have been thoroughly studied. Thanks to a smartwatch, I have been a student for the past year-and-a-half, trying to figure out ways to get a better night’s rest. Between late-night check-ins at hotel rooms and early-morning flights, I have become a lousy sleeper.
My smartwatch tracks when I’m in deep sleep, light sleep, REM sleep, when I move around, and how many interruptions I have, and it even gives me a score for the night. But there are much more accurate ways to measure sleep in a lab.

So, for the good of the story, I put on a hospital gown and pajamas and got wired up at the UCLA Sleep Disorder Center.

That’s a lot of wires.

(LAUGHTER)

JOEL RECTOR, UCLA Sleep Disorder Center: Yes, I believe 32.

HARI SREENIVASAN: Lab manager Joel Rector placed sensors on specific parts of my head to measure electrical activity in my brain, stuck some near my eyes and on my legs to measure even the slightest twitches, and strapped sensors around my chest and stomach to gauge my breaths.

JOEL RECTOR: I’m going to put this over your shoulder.

HARI SREENIVASAN: Doesn’t feel like the most natural way to go to sleep.

And I did something I have never done at work. I tried to fall asleep on the job.

So, just to run through this, all these are measuring my brain waves. This is measuring my breath and oxygen. This is measuring how much I’m moving here and here and on my legs. And this is measuring my oxygen.

JOEL RECTOR: Yes.

HARI SREENIVASAN: OK.

JOEL RECTOR: All righty. Well, I will get the lights off.

HARI SREENIVASAN: Good night.

While I napped, Rector monitored my patterns.

JOEL RECTOR: He’s in stage two sleep, which is what most people are in for the majority of the night. He’s kind of just sleeping quietly.

HARI SREENIVASAN: When I woke up, I had a chat with neuroscientist Alon Avidan, who runs the sleep disorders lab, to tell me what he saw.

DR. ALON AVIDAN, Director, UCLA Sleep Disorder Center: Typically, when we ask someone to fall asleep, we don’t see them fall asleep in less than eight minutes. You fell asleep in less than a minute, which means that…

(LAUGHTER)

DR. ALON AVIDAN: … you are probably sleep-deprived.

HARI SREENIVASAN: What can happen if you’re chronically sleep-deprived?

DR. ALON AVIDAN: The data shows that in people who are chronically sleep-deprived, the immune system doesn’t work as well. You’re more prone to develop obesity, diabetes. Cognitive function tends to become depressed.

HARI SREENIVASAN: But what constitutes sleep deprivation?

Max Hirshkowitz is chair of the National Sleep Foundation, and a guest lecturer at Stanford Medical School. He recently convened a panel of experts to recommend how much sleep we should get.

MAX HIRSHKOWITZ, National Sleep Foundation: About seven to nine hours. It’s a range. Now, six may be appropriate under unusual circumstances, but, otherwise, seven to nine, somewhere in there.

HARI SREENIVASAN: There is no shortage of pills that try to deliver those seven to nine hours.

NARRATOR: Sleep better, sleep longer.

NARRATOR: There’s a land of restful sleep. We can help you go there.

HARI SREENIVASAN: And that concerns Siegel.

JERRY SIEGEL: The thing that alarms me is this thought that — and this was the motivation for undertaking the study, to find out if this true — that we used to sleep much more, and that we need to increase our sleep from whatever number we get to be closer to 10, 11 hours of sleep. The data that we have gathered indicates that’s not the case.

HARI SREENIVASAN: In fact, these people Siegel studied average less than six-and-a-half-hours, and they seem fine.

JERRY SIEGEL: In general, the adults are more healthy than those in our society. They may for some reason need less sleep, but there certainly doesn’t seem to be any negative consequence resulting from their sleep pattern.

HARI SREENIVASAN: They also don’t appear tired during the day. They hardly nap and they sleep soundly when they do.

JERRY SIEGEL: One thing we found is that these groups have very little insomnia, maybe at a 10th the incidence we have, and so there’s something different there that’s going on.

HARI SREENIVASAN: That something will take more research to figure out.

So, back to the lab, or, in this case, back to bed.

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Robots teach themselves martial arts to avoid smashing into the ground

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ESCHER (Electromechanical Series Compliant Humanoid for Emergency Response) robot takes a tumble at the Defense Advanced Research Projects Agency Robotics Challenge June 5, 2015 in Pomona, California. Photo by Chip Somodevilla/Getty Images

ESCHER (Electromechanical Series Compliant Humanoid for Emergency Response) robot takes a tumble at the Defense Advanced Research Projects Agency Robotics Challenge June 5, 2015 in Pomona, California. Photo by Chip Somodevilla/Getty Images

A few weeks ago, I slipped in the shower, and after a cartoonish sequence of body contortions, I caught myself while landing. Robots aren’t as lucky. As June’s DARPA Robotics Challenge taught us, when machines fall, they tumble terribly and without the ability to brace themselves.

But those days might be over thanks to a computer program created by scientists at the Georgia Institute of Technology in Atlanta.

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A new algorithm from allows robots to fall with style. Video by Georgia Institute of Technology

As IEEE Spectrum describes, the new algorithm uses “techniques adapted from judo,” allowing a robot to learn how to position its appendages while tumbling.

So rather than the full impact being felt by a single part of the robot, the robot can displace the kinetic energy created during the fall over multiple parts of its body. By learning how to tumble, robots reduced impact intensity to the head by 30 to 90 percent.

Robot somersault. Image by Georgia Tech

Robot somersault. Image by Georgia Tech

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New imagery from Pompeii yields surprising findings about ancient humans

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POMPEII, NAPLES, ITALY - 2015/09/29: (EDITORS NOTE: Image contains graphic content.) A working team appointed by the Archaeological Superintendence of Pompeii performs a CAT (Computerized Axial Tomography) scan on one of thirty casts of the victims of the eruption of Vesuvius in 79 AD in Pompeii. (Photo by Ciro De Luca/Pacific Press/LightRocket via Getty Images)

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MEGAN THOMPSON: Two-and-a-half million people visit Pompeii every year, making it one of Italy’s busiest tourist attractions.

The ancient city, close to modern-day Naples, is famous for being frozen in time, preserved as it was when the volcano Mount Vesuvius erupted more than 1,900 years ago, in 79 AD.

Pompeii, buried in tons of volcanic ash, along with the remains of some 2,000 people killed, was first excavated in the 1800s.

Those early discoverers poured plaster on the recovered bodies to better preserve them, but little was known about them.

So, last month, researchers brought in a CAT scan machine, like the one you might find in a doctor’s office.

The machine penetrates the thick plaster and creates a 3-dimensional image of each body. The CAT scans reveal two big discoveries.

First, many victims did not die from suffocation, as previously thought, but from the falling buildings.

MASSIMO OSANNA, DIRECTOR: From the analysis carried out on the bones, we have found a lot of broken skulls. This tells us many died from falling roofs under the pressure of the pumice. The pumice is very light but when it builds up two meters, it can collapse roofs and many died because of this.”

MEGAN THOMPSON: Second, the researchers are finding many of Pompeii’s victims had practically perfect teeth, a reflection, perhaps, of a healthy Mediterranean diet low in sugar and high levels of fluoride in their water supply.

MASSIMO OSANNA, DIRECTOR: From the study, we discovered the absence of cavities in the teeth. This is very interesting, it is not completely surprising because we know about the Mediterranean diet and it’s positive aspects.

MEGAN THOMPSON: The researchers plan to scan all 86 casts of the human remains to help us learn more about not only how the people of Pompeii died, but how they lived.

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The countries where global warming will shrink bank accounts

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A new study from Stanford pinpoints the best annual temperature for getting the job done. Photo by H. Armstrong Roberts/ClassicStock/Getty Images

A new study from Stanford pinpoints the best annual temperature for getting the job done. Photo by H. Armstrong Roberts/ClassicStock/Getty Images

It’s no secret that summer lends itself better to beaches and barbecues than actual work. Yet the instinct to shirk work in hot weather is more than a summer slowdown. It’s a broad phenomena that may cripple some nations as global warming progresses.

A new study from Stanford University has pinpointed the optimal annual temperature for economic productivity, and it’s this: 55.4 degrees Fahrenheit, or 13 degrees Celsius. The researchers show that when the climate exceeds this temperature, the country’s economic output drops precipitously. Based on their model published today in the journal Nature, this pattern has held steady for more than 150 countries, affecting both rich and poor, for more than half a century.

science-wednesday

If global warming isn’t checked, the team expects average global incomes will be slashed by a quarter by 2100. So whether you’re an Indonesian rice farmer baking in the hot sun or a tech jockey sitting in a cool Silicon Valley office, you can expect your economic prosperity to decline.

“The results indicate that societies will need to adapt in ways that are likely to be expensive, or [they will] face even greater damages in terms of lost GDP,” said economist Michael Greenstone of the University of Chicago, who wasn’t involved in the project.

Stanford economist Marshall Burke and his colleagues created this new projection for the future by treating 166 countries like patients getting regular health checkups.
The team isolated the annual temperatures of each country from 1960 to 2010, and then looked at how that country’s economy performed during each of those years. By comparing warm years to normal years, the team was able to chart how individual economies respond to temperature.

A prediction for how gross domestic product (GDP) will change across the globe by 2100. This model assumes a "business as usual" global warming scenario, wherein unmitigated climate changes raises temperatures by 4.3 degrees Celsius (8 degrees Fahrenheit) by the end of the century. Photo by Burke M,  Hsiang SM and Miguel E., Nature, 2015.

A prediction for how gross domestic product (GDP) will change across the globe by 2100. Colder countries, like Canada, will see an economic boost with climate change, while most tropical nations will witness a drop. This model assumes a “business as usual” global warming scenario, wherein unmitigated climate changes raises temperatures by 4.3 degrees Celsius (8 degrees Fahrenheit) by the end of the century. Photo by Burke M, Hsiang SM and Miguel E., Nature, 2015.

Even when accounting for cultural differences, technological innovations, political upheavals, and economic atom bombs like global recessions, these researchers found an optimal temperature — again, 55.4 degrees Fahrenheit — that, in Burke’s words, “is really good at producing stuff around the world.”

“What we see is it matters less if you’re rich or poor now. It matters more if your [annual] average temperature is hot or cold,” Burke said. “If your country’s temperature is cooler than [55 degrees Fahrenheit], then global warming might help you. If your average temperature is hotter, a little bit of warming might hurt you.”

On a small scale, it’s easy to see how temperatures could impair industries like outdoor construction or agriculture. A drought during a growing season can wipe out crops, whether you’re a midwestern farmer in the U.S. or in Sub Saharan Africa.

But by examining the macroeconomics of climate change, the findings by Burke and his companions support a budding phenomena wherein even white collar jobs in air-conditioned offices will feel the burn of global warming. Prior research in India, for instance, suggests that worker productivity in textile mills drops by “1 to 3 percent per degree Celsius,” despite limited heat stress in the factories. Meanwhile, automobile assembly lines in the U.S. slow down when temperatures outside become too hot.

Photo by moodboard/via Getty Images

Photo by moodboard/via Getty Images

“We are already experiencing the economic impacts of climate change — heatwaves, for example, are increasing health costs and employee absenteeism,” economist Thomas Sterner of the University of Gothenburg wrote in accompanying commentary also published today by Nature.

The explanations for the decline in white-collar industries remain unclear, Burke said. What we do know is society gets a little crazy when it’s hot. Fatal car accidents and violence escalate. The rate of heart attacks spikes. Sleep might also be a factor. Burke’s team is currently looking into how sleep quantity and quality dictate economic output on a broad scale.

“It’s an intuitive idea, and we’re searching for quantitative evidence at the moment,” Burke said. Like an itchy, uncomfortable sweater, global warming might simply aggravate society by building collective stress among groups of people.

Until today, the conventional wisdom was that the economic burden of global warming would primarily be felt by poor nations. A seminal study in 2008 drew the relationship between temperature and economic output as a straight line. “The higher temperature, the bigger the costs,” Sterner writes, which meant that low-income nations would be burdened heavily in the future, given most reside in warm climates.

Cornfields during a drought in Tanzania. A 2012 study from MIT predicts that Sub Saharan Africa will witness a decline in the yields of its most common crops over the next century.   Photo by Dennis K. Johnson/via Getty Images

Cornfields during a drought in Tanzania. A 2012 study from MIT predicts that Sub Saharan Africa will witness a decline in the yields of its most common crops over the next century. Photo by Dennis K. Johnson/via Getty Images

Sterner writes that by not assuming a linear relationship, the new model from Burke’s team paints a more accurate picture. It can account for nuanced, micro-level responses between economic productivity and temperature.

As a country’s average temperature gets hotter and extends further past the 55-degree Fahrenheit threshold in Burke’s model, economic productivity fares worse. Poor countries would still suffer the brunt of unmitigated climate change over the next century, but rich countries take a hit too. The annual temperatures for nations like China and the U.S. already hover around the 55 degree-Fahrenheit cliff, so they might witness Overall, 77 percent of the countries surveyed could be poorer by 2100 due simply to global warming.

Temperature effects on GDP over time for nine regions. Black lines are projections using point estimates. Red shaded area is 95% confidence interval, colour saturation indicates estimated likelihood an income trajectory passes through a value. Photo by Burke M,  Hsiang SM and Miguel E., Nature, 2015.

Temperature effects on GDP over time for nine regions. Black lines are projections using point
estimates. Red shaded area is 95% confidence interval, colour saturation
indicates estimated likelihood an income trajectory passes through a value. Photo by Burke M, Hsiang SM and Miguel E., Nature, 2015.

“All told, these estimates equate to much larger economic losses than most leading models suggest…,” Sterner writes. “ The current leading models, referred to as integrated assessment models (IAMs), are already being used as a basis for policy. In the United States, there have been considerable battles, even in Congress, concerning the ‘social cost of carbon’, which is based on the three most prominent IAMs.”

Burke’s study argues that Congress and other policy agencies have based their predictions on the social costs of global warming and carbon pollution on estimates that are off by several hundred percent.

“[This study] is part of a growing literature suggesting that climate change is more harmful than current models indicate,” Greenstone said.

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Do bigger family jewels mean deeper voices (in howler monkeys)?

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A chorus of howler monkeys of the species Alouatta caraya. Photo by Mariana Raño

A chorus of howler monkeys of the species Alouatta caraya. Photo by Mariana Raño

Baby, I’m howlin’ for you. Male howler monkeys make deep and boisterous calls to attract mates, but the deepest-pitched songs may come at cost: the size of their testicles. A new study in the journal Current Biology examines this relationship and reveals the untold story of the sacrifices male howler monkeys make when facing competition for mates.

University of Utah primatologist Leslie Knapp and her colleagues were interested in these howls, not only because they’re so boisterous, but because their sound can vary dramatically between species and individuals.

Knapp told PBS NewsHour:

If you’ve ever been South America, and you hear a loud howl early in the morning, it’s probably a howler monkey. They’re communicating about where they are and what’s going on. Both males and females make the noise, but you can detect small differences between individuals in the social group, in terms of the depth and the pitch and the amount of howling that is done.

In case, you haven’t heard a howler monkey, here’s an example:

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More from Knapp:

You can see how much effort it takes. It’s a rhythmic howl, as it gets closer to the end, you can see this male gets kind of agitated. It makes as much effort as possible to make more noise and get a deeper sound to the surrounding audience. Female may use these signals and others to tell if the male is more fit.

To glean what controls these howls, Knapp sent one of her researchers, Jacob Dunn, to museums across Europe and the U.S. Dunn combed these collections for preserved specimens of howler monkeys, namely their hyoid bones. A hyoid is U-shaped bone in the throat that cages the vocal chamber. Its size is thought to dictate if a primate’s call has a low or high pitch.

Dunn and his colleagues used 3-D laser scans to measure the volumes of 255 hyoid bones from nine howler monkey species.

This photo is of a 3-D laser surface scanning of a howler monkey hyoid bone. Photo by Jacob Dunn

This photo is of a 3-D laser surface scanning of a howler monkey hyoid bone. Photo by Jacob Dunn

Next, researchers read papers or made hand measurements with calipers to collect data on the testicle size of monkeys from five of those species. They also looked at data on the monkey’s social group size, body weight, skull length and canine length. Plus they record vocalizations among different howler monkey species in South America. Their goal: to discern what features might correlate with the sound of a howler monkey’s love call.

They found that there are a number of sexual trade-offs when it comes to howling. First, male hyoids were three to eight times bigger than female hyoids. The biggest males had hyoids were 10 times larger than the smallest males.

“The male monkeys with the deepest- and lowest-pitched howls are giving the impression of having a much bigger body than they actually do,” Knapp said. “Male howler monkeys weigh about 20 pounds or less, but the kins of sounds of the deepest vocalizations compare to what might be made by tigers or red deer.”

One might describe this as the Barry White phenomena.

This photo displays (clockwise) a skull, mandible and hyoid bone of a red howler monkey, indicating the enormous size of the hyoid relative to other body parts and total body size. Photo by  Jacob Dunn

This photo displays (clockwise) a skull, mandible and hyoid bone of a red howler monkey, indicating the enormous size of the hyoid relative to other body parts and total body size. Photo by Jacob Dunn

“Females of our own species tend to find deeper voices, like soul vocalist Barry White’s, more attractive and romantic,” Knapp said in a statement. “Deeper voices are thought to reflect a larger body size, which could represent a good choice for a mate.”

But with howler monkeys, the sexual trade-offs don’t end with voices. Male monkeys with larger hyoids, which make lower-pitched calls, had smaller testicles. They also tended to live in isolation with a community of a few females.

In contrast, males with smaller hyoids had bigger testes and lived in groups where they had to compete with other suitors for female mates.

Given females have more partners to choose from, males living in large groups may have evolved larger testes in order to make more sperm. More sperm means that they can spread their seed further throughout their community, elevating the odds that their genes will be passed onto to the next generation.

“We know that testes size often results as a consequence of male-male competition. For instance, chimps have large testes, so they can produce more sperm,” Knapp said.

The tradeoff appears to be hyoid size and vocal range. A male howler monkey living in a harem community by himself may have evolved to warn off other suitors with deeper calls. At the same time, his balls shrank, since there is less competition.

In future work, Knapp and her colleagues plan to see if these factors — howl pitch and testes — determine mating success in howler monkeys living in Mexico.

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Will you die prematurely? This blood test may contain the answer

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Higher levels of a set of blood markers correlate with premature death, and scientists may have figured out why. People Photo by JGI/Jamie Grill/via Getty Images

Higher levels of a set of blood markers correlate with premature death, and scientists may have figured out why. People Photo by JGI/Jamie Grill/via Getty Images

A blood test claims to provide more information on if, how and why a healthy person will die in the next decade.

Two things in life are ultimately certain: the day you’re born and the day you die. We know one, and the other drives many of our lifestyle choices, even though it’s hard to pinpoint the exact date that we’ll expire.

But what if you could narrow a person’s death date to a precise window? In a study published today in the journal Cell Systems, computational biologists suggest that a simple blood test can tell if an otherwise healthy person is likely to die from pneumonia or sepsis within a decade.

We made the initial discovery of these mortality biomarkers 1.5 years ago, said Johannes Kettunen, who studies “metabonomics” with the University of Oulu and the National Institute for Health and Welfare in Finland. Metabonomics is economics for the human metabolism.

Metabonomicists try to quantify the compounds consumed and produced by our body’s cells. To do so, researchers like Kettunen comb metabolic data from thousands of patients over long periods of time, in order to discern the evolution of our human soup.

In 2011, Kettunen and his colleagues examined blood samples from 10,000 Estonian and 7,000 Finnish subjects, among which 684 patients had died in a five-year follow-up period. They were searching for biomarkers in the samples that might have been an indicator for death, and they found one. A chemical process and byproduct of inflammation, called glycoprotein acetylation (GlycA), predicted whether a person would die from cancer, cardiovascular disease and nonvascular disease. These trends held true even when subtracting for factors like age, weight, smoking, cholesterol levels and preexisting conditions like diabetes and cancer.

“People with a biomarker score in the top 20 percent had a risk of dying within five years that was 19 times greater than that of individuals with a score in the bottom 20 percent (288 versus 15 deaths),” Kettunen wrote in PLOS Medicine.

Yet this information isn’t very useful unless scientists know why these deaths are linked to GlycA. Skeptics might say, “If you look at a large enough group, I’m sure some biological feature will connect their experience.”

This week, Kettunen and his colleague Michael Inouye, a human genomicist at the University of Melbourne in Australia, are back with a sequel. They’ve crunched the data from the original Finnish group as well as a new cohort of 3,500 young Finns that have been monitored since 1980.

By looking at how human genes respond in folks with a spectrum of GlycA levels, the researchers conclude that those with persistently high GlycA exist in a constant state of inflammation. It’s as if they’re fighting a virus or bacterium that isn’t there. Their bodies switch on the production of infection-fighting compounds, called cytokines, and they call upon immune cells — called neutrophils — that typically battle infections.

Chronic inflammation wears at a person’s body and can predispose people to catching infections. Akin to their results from 2011, the researchers found that elevated GlycA levels increased a person’s chances of being hospitalized with or dying from fatal infections. Overall, GlycA blood markers can predict death from infection up to 14 years in the future.

This schematic summary of the  investigation into the biology of GlycA, a known biomarker for short-term mortality. It reveals GlycA's long-term behavior in apparently healthy patients. GlycA levels can be stable for >10 years and are associated with chronic low-grade inflammation. Accordingly, GlycA predicts death from infection up to 14 years in the future. Illustration by Ritchie et al. Cell Systems, 2015

This schematic summary of the investigation into the biology of GlycA, a known biomarker for short-term mortality. It reveals GlycA’s long-term behavior in apparently healthy patients. GlycA levels can be stable for >10 years and are associated with chronic low-grade inflammation. Accordingly, GlycA predicts death from infection up to 14 years in the future. Illustration by Ritchie et al. Cell Systems, 2015

Kettunen suspects high GlycA levels are caused by a low-grade, runaway inflammatory response, but it’s possible that the condition results from a hard-to-detect infection by a virus or bacteria.

Clearing up the mystery behind the GlycA risk could be valuable not only for addressing our morbid curiosity, but also from a public health perspective. However, based on these two studies, it is hard to assign a number on how many people in the general population might have elevated GlycA, Kettunen said.

“We want to short-circuit that risk, and to do that we need to understand what this blood biomarker of disease is actually telling us,” Michael Inouye said in a statement.

But a person’s ability to learn their GlycA profile raises an ethical question, since there’s no known treatment for tweaking it.

“If we can find something that also lowers the health risks indicated by GlycA, then it may be useful to take. Until then, I think it is better not knowing,” Kettunen said.

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Before the bubonic plague wrecked Europe, it was way less contagious

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Scene from "The plague in Marseilles in 1721" by Michel Serre. The Great Plague of Marseilles was the last large-scale European outbreak of the disease. Photo by DEA / G. DAGLI ORTI/via Getty Images

Scene from “The plague in Marseilles in 1721″ by Michel Serre. The Great Plague of Marseilles was the last large-scale European outbreak of the disease. Photo by DEA / G. DAGLI ORTI/via Getty Images

You may know the bubonic plague — an infection caused by Yersinia pestis bacteria — by its medieval name: The Black Death. But thousands of years before this pestilence wiped out 30 to 50 percent of the European population in the 1300s, it potentially circulated among humans as a harmless microbe, according to a study published Thursday in the journal Cell.

The new findings argue that the plague infected humans as early as the Bronze age, nearly 3,300 years before historical records began charting the disease. Researchers made this discovery by examining ancient DNA in human teeth from Asia and Europe. In total, they looked at dental samples from 101 people who lived from 2,800 to 5,000 years ago.

They found the DNA of Yersinia pestis bacteria in seven individuals, the oldest of which walked the earth around 2794 B.C. Until now, the earliest known DNA sample of this bacteria dated to the sixth century Plague of Justinian.

The photo shows a Bronze Age human skull from the Yamnaya culture painted with red ochre. Yamnaya later developed into the Afanasievo culture of Central Asia, one of the cultures that carried the early strains of Yersinia pestis a.k.a. the plague. Photo by Rasmussen et al., Cell, 2015.

The photo shows a Bronze Age human skull from the Yamnaya culture painted with red ochre. Yamnaya later developed into the Afanasievo culture of Central Asia, one of the cultures that carried the early strains of Yersinia pestis a.k.a. the plague. Photo by Rasmussen et al., Cell, 2015.

By comparing this ancient strain of plague with younger specimens, the team was able to build a timeline of the bacteria’s evolution. They learned that the Bronze Age plague didn’t possess a gene called Yersinia murine toxin, which allows the disease to replicate in fleas and ultimately spread like wildfire. However, Yersinia murine toxin does appear in an Iron Age sample, suggesting the bacteria began using fleas as transportation approximately 3,700 and 3,000 years ago.

Based on this evolutionary analysis, two of the oldest Bronze Age Y. pestis bacteria also produced a protein called flagellin. This proteins makes it easier for the human immune system to spot an infection. In later versions of the germ, flagellin is mutated, allowing the bacteria to escape detection in humans.

These findings suggest that the plague wasn’t always such a bad bugger. For more, check out this article in Smithsonian Magazine.

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NASA carefully steers New Horizons mission toward second target

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Artist's impression of NASA's New Horizons spacecraft encountering a Pluto-like object in the distant Kuiper Belt. If NASA approves a proposal to extend New Horizons' mission by 2016, the spacecraft would reach an object named 2014 MU69 in the far reaches of the solar system by 2019. Image courtesy of Alex Parker/NASA/JHUAPL/SwRI

Artist’s impression of NASA’s New Horizons spacecraft encountering a Pluto-like object in the distant Kuiper Belt. If NASA approves a proposal to extend New Horizons’ mission by 2016, the spacecraft would reach an object named 2014 MU69 in the far reaches of the solar system by 2019. Image courtesy of Alex Parker/NASA/JHUAPL/SwRI

After months of beaming back one awe-inducing photo after another of Pluto’s icy landscape, NASA’s New Horizons spacecraft is heading toward a new destination roughly one billion miles away from the dwarf planet.

Flight controllers at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland initiated the first of four maneuvers Thursday that are needed to change the probe’s trajectory toward an object elsewhere in the Kuiper Belt.

Since the spacecraft is three billion miles from Earth, all four commands will take two weeks to complete, the Associated Press reported.

The New Horizons team selected the destination for a secondary mission in August. The target is an object known as 2014 MU69, or “Potential Target 1″ (PT1). The probe is expected to reach the nearly 30-mile-wide object in the far reaches of the solar system by January 2019, though NASA must receive approval from an independent panel before they can fully execute the second mission. NASA’s proposal to fund the flyby and documentation of the 2014 MU69 object is due in 2016.

Little is known about PT1, even though it was discovered in 2014 by the Hubble Space Telescope. NASA scientists have also said a flyby in a largely unexplored region of space would provide clues to understanding the solar system’s birth, which occurred around 4.6 billion years ago.

Hubble discovery images of "PT1," or "Potentially Target" 1. Image courtesy of NASA/ESA/SwRI/JHU/APL

Hubble discovery images of “PT1,” or “Potentially Target” 1. Image courtesy of NASA/ESA/SwRI/JHU/APL

The PT1 object is approximately one percent the size of Pluto, but 10 times larger than a typical comet. NASA said that the New Horizons spacecraft was equipped with excess nuclear fuel to potentially tackle a second flyby. PT1’s location is reachable with the fuel leftover from New Horizon’s historic flyby of Pluto.

Lead scientist Alan Stern told AP that the goal was to get the New Horizons spacecraft closer to PT1 than the distance — 7,770 miles — it came within Pluto.

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The science of how Hurricane Patricia became so colossal

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Hurricane Patricia as viewed from the International Space Station. Photo by Scott Kelly/NASA

Hurricane Patricia as viewed from the International Space Station. Photo by Scott Kelly/NASA

In early July, six cyclones struck the Pacific Ocean at once, marking the first time in a decade that this ocean has hosted five or more weather events with tropical storm strength. The following month, two storms with super-typhoon intensity — Goni and Atsani — marched across the Pacific in the same week — that hasn’t happened since 1997.

Now, Hurricane Patricia, the strongest storm ever recorded in the western Hemisphere, is churning across the Pacific on its way to Mexico, raising a number of questions:

Is El Niño responsible for these storm patterns? Partly, but not totally.

Is Patricia the worst storm ever in the Western Hemisphere? Depends on what you’re measuring.

How bad will Patricia be? By some measures, potentially as bad as hurricane Katrina.

And why is Patricia called a hurricane, not a typhoon, if it’s in the Pacific? Because of an arbitrary decision in 1945.

Let me explain.

Did El Niño cause Patricia?

In a word, no. You can’t attribute a single weather event to global climate change or El Niño.

But El Niño has contributed to the storm’s intensity, said Accuweather meteorologist Dan Kottlowski.

Water temperatures in the Eastern Pacific and along the West Coast are warmer than normal. In fact, Kottlowski said, off the coast of Mexico, the water temperatures are by far some of the warmest that have ever been measured since meteorological buoys and satellites began covering the area in the 1970s.

El Niño has also reinforced Patricia and other storms in the Pacific Basin by lowering wind shear.

Cyclones form when ocean temperatures reach 80 degrees Fahrenheit, which heats the air just above the water. That air rises into the cooler portions of the atmosphere, moving massive amounts of air and creating strong winds. The rising humid air also spawns the giant clouds of a cyclone.

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Wind shear occurs when winds move at different speeds at different heights. For example, if there is no wind on the ground but 100 mile per hour winds at the top of the Empire State Building, then you’d say that location has high wind shear. If winds are moving at the same speed, then there is no wind shear.

Cyclones love conditions when there is little wind shear, and that’s what El Niño has done to the northern Pacific Ocean. One readout for this potency is accumulated cyclone energy, or ACE.

“We use what’s called ACE to calculate the energy expelled by tropical cyclones in a year,” Kottlowski said. “That value has been phenomenal this year, much higher than normal. Right now, it’s near a record amount.”

In fact, according to Slate’s Eric Holthaus, “Patricia is now very close to the theoretical maximum strength for a tropical cyclone on planet Earth.” El Niño is also triggering droughts in eastern Africa.

Ironically, El Niño and wind shear have combined to create a weaker than usual hurricane season in the Atlantic Ocean and Caribbean Sea, according to Kottlowski.

If you’ve ever played with a spinning top, you know that if you tilt the top, it will fall over, Kottlowski said: “It’s the same thing with the atmosphere. What it’s basically doing is all the thunderstorms are getting blown off to the right or the left.”

Spinning top

The fast-moving winds from the west and resulting wind shear are cutting tropical storms to ribbons.

“In the Atlantic Basin, it’s pretty typical when there’s an El Niño that you don’t see as many storms developing. I looked at a graph of the shear across the Caribbean. It’s probably the strongest shear that we’ve seen across the Caribbean. That’s why there have been fewer storms,” Kottlowski said.

Is Patricia the worst storm to ever hit the Western Hemisphere?

The only way to know the true strength of a hurricane is by making measurements inside the storm, which is typically done with weather buoys in the water or by reconnaissance plane.

“It just so happens that [Air Force Hurricane Hunters] had an aircraft into the storm late yesterday,” Kottlowski said.

If you don’t have an aircraft, then you’re using satellite imagery to estimate the wind speeds and the pressure, which is less accurate.

“Patricia is the first hurricane where a reconnaissance aircraft has measured a wind speed of 200 miles per hour and pressure down to 880 millibars in the Eastern Pacific,” Kottlowski said

It’s conceivable that other storms in this region were underestimated. For example, a recon plane wasn’t available for Hurricane Linda in 1997. People estimated a pressure of 902 millibars, but that measurement was made with satellite estimates.

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Conceptual animation illustrates the wind damage associated with increasing hurricane intensity, based on The Saffir-Simpson Hurricane Wind Scale. Video by Climate Central.

So as far as we know, Patricia has set a pressure record, topping Hurricane Wilma from 10 years ago. But why does it matter?

“Lower pressure gives a guesstimate of what the wind is going to be. The pressure doesn’t do any damage,” Kottlowski said. “It just gives a measure of how intense the storm is. The lower the pressure, potentially the stronger the winds.

Wait, is Patricia a hurricane, a cyclone or a typhoon?

All of the above. From a meteorological view, hurricanes, cyclones and typhoons are one in the same. They’re all storms born in tropical waters., Hurricanes, cyclones, typhoons, tropical depressions and tropical storms are all technically known as tropical cyclones.

When did people start using these different terms?

According to an article published in 1880 by the Royal Geographical Society of London, the word “typhoon” was first mentioned in print in 1560 by Portuguese explorer Fernão Mendes Pinto. From the article:

“The history of this word which, at the present day, may be considered the common property of about all European languages, is buried in the first reports of Western travellers on their adventures in Chinese waters.

The earliest print making mention of a typhoon seems to be “Pinto’s Journey,” first published in 1560. Here the word appears in its Portugese form at tufaõ, and Pinto himself says that this storm, which he encounterd on two occasions, is so called by the Chinese…The present spelling, typhoon, may be traced to the end of the 17th century; Lecomte, whose Memoirs first appeared in 1693, describing a Typhon, thus spelt.

This account speaks to the regional legacies of describing these storms. The word hurricane derives from the Spanish word “huracan”. Its roots sprouted among Spaniard colonists, who borrowed it from Hunrakan, the Mayan storm god, and Hurakan, a Taino and Carib god, according to The Weather Channel. Cyclone comes from the Greek word for circle, kuklos, but British merchant Henry Piddington is credited for applying the term toward an Indian Ocean storm in 1845.

How are these storms classified today?

The local derivatives stuck, Kottlowski said.

Hurricane is used for storms in the western Atlantic, Caribbean and eastern Pacific.

In the Northwest Pacific, people use the word “ typhoon”, though when the storms reach Category 4 or above 150 miles per hour, they’re called “super typhoons.”

Around Australia, India and throughout the Indian Ocean, these storms are called cyclones. Cyclon is also used for the rare occasions when a tropical storms hits the Mediterranean Sea, which has only happened five times since 1947.

Forecasters have been naming tropical cyclones since the late 19th century, but the habit didn’t become an official practice until 1945, when U.S. armed servicemen in the Western Pacific started naming the storms after their wives. This naming system became alphabetized two years later, according to the National Oceanic and Atmospheric Administration’s Hurricane Research Division:

“Starting in 1947, the Air Force Hurricane Office in Miami began designating tropical cyclones of the North Atlantic Ocean using the Army/Navy phonetic alphabet (Able-Baker-Charlie-etc.) in internal communications. During the busy 1950 hurricane season there were three hurricanes occurring simultaneously in the Atlantic basin, causing considerable confusion. Grady Norton then decided to use the Air Force’s naming system in public bulletins and in his year-end summary. By the next year, these names began appearing in newspaper articles.”

The Interdepartmental Hurricane Conference and the U.S. Weather Bureau officially adopted the practice of using female names for hurricanes in 1953, which caused an uproar, according to The Weather Channel. Equal rights activists fought for nearly 30 years to change the practice. Male names were finally adopted in 1979.

In 2014, a study in PNAS claimed hurricanes with female names caused more damage because they spur less fear in the general public; however, as Ed Yong highlighted for National Geographic, experts question the statistical methods used in the research.

The reckoning.

Kottlowski expects that Patricia will do serious damage this weekend. The storm is expected to make landfall just to the west of Manzanillo, Mexico and hit the Sierra Madre mountains..

“The low level part of the storm will fall apart, but the upper level structure of the storm will continue to transport deep tropical moisture through central mexico and into the US,” he said.

The storm will drop up to 6-12 inches, though higher terrain could see rainfall totals of up to 2 feet.

Extreme storm surge is expected to hit the coast. Early estimates predict a surge of 10 feet, though Kottlowski said that it could be much worse.

This satellite image from the National Oceanic and Atmospheric Administration shows Hurricane Patricia in the Pacific Ocean headed toward the Mexican coast.

Hurricane Patricia should make landfall in Mexico Friday evening. Image by the National Oceanic and Atmospheric Administration.

“When we look at surges with some of the bigger storms that hit the U.S., such as Hurricane Katrina, we see a storm surge of 25 to 26 feet. It’s conceivable that [Patricia] could create a storm surge that high.”

Once Patricia moves into the mountains, rain will be the biggest threat. Kottlowski said places like Puerto Vallarta, Guadalajara, and Manzanillo, Mexico are going to see a lot of rainfall, flooding and mudslides — all will be life threatening.

The storm will track eastward into the U.S. and develop into big rainstorm near the Texas coast, dumping heavy rain tomorrow, Sunday and perhaps into Monday over Southeast Texas.

The post The science of how Hurricane Patricia became so colossal appeared first on PBS NewsHour.

How the ingredients for a catastrophic storm came together for Hurricane Patricia

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Hurricane Patricia, a category 5 storm, is seen approaching the coast of Mexico in a NOAA satellite image taken by GOES East at 10:45 ET (14:45 GMT) October 23, 2015. Patricia, one of the strongest storms ever recorded, bore down on Mexico's Pacific Coast, prompting the evacuation of thousands of tourists and residents and a mad rush for emergency supplies. The U.S. National Hurricane Center reported on Friday morning Patricia had maximum sustained winds of about 200 miles per hour (321 km per hour) as it moved north at 10 mph (16 kph).   REUTERS/NOAA/Handout via Reuters  THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. IT IS DISTRIBUTED, EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS - RTS5VCC

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JUDY WOODRUFF: Hurricane Patricia has been described as potentially one of the most dangerous storms to ever hit the Western Hemisphere. Meteorologists now say that Patricia is bringing with it winds of 190 miles an hour, down just slightly from earlier.

William Brangham has more on the storm itself and what is fueling it. He recorded this interview a short time ago, as the storm was approaching Mexico.

WILLIAM BRANGHAM: Bob Henson is a meteorologist for Weather Underground, a Web-based weather service that also has a weekday show on The Weather Channel. Henson is also author of five books on weather and climate change.

So, Bob Henson, it seems like meteorologists like yourself have run out of terms to describe the intensity of the storm. Yesterday, it was a Category 1. We wake up this morning, it’s a Category 5. How did this storm get so big so fast?

BOB HENSON, Weather Underground: It’s a true outlier.

You know, there’s only a very, very few hurricanes or typhoons in world history that we know about that have intensified so quickly. They have really only been observing these systems in depth for the last several decades, say, so we can’t really say how strong hurricanes were in 1900 or 1800.

But, certainly in the modern era of hurricane hunting and satellites, for a storm to go to from a tropical storm to a Cat 5 in, say, 24 hours, 30 hours, those kinds of numbers only happen once in a very rare while. So, this is up in the ranks of maybe the top three or four most rapidly strengthening storms.

And, basically, it’s because it was over extremely warm water that went to some depth, so the winds didn’t stir up colder water to weaken it. And upper winds were very weak, which allowed it to intensify rapidly. Really, just all the ingredients came together in just the right way, which, surprisingly, doesn’t happen all that often.

WILLIAM BRANGHAM: You mentioned that calling this a Category 5, which is the top of the Saffir-Simpson scale, is almost an insufficient description of this storm. Can you explain?

BOB HENSON: Yes.

The Saffir-Simpson scale was developed several decades ago, and it breaks hurricanes down into five bins, Category 1 all the way up to Category 5. Now, most of those bins are about 28-to-30-miles-per-hour-wide, you might put it. Category 5 starts at 156 miles an hour, but it has no ceiling. It’s 156 and up.

This storm had peak winds of 200, so it was 45 miles an hour above the Category 5 threshold. You might say that, if we had a Cat 6 and Cat 7, that it would fall in the Cat 7 range, close to that. We don’t parse storms out when they get so strong, in part because once you get to Cat 5, it pretty much destroys everything except a really well-constructed building, so there is not as much operational significance to it.

WILLIAM BRANGHAM: So, at that level of intensity, is that what we’re expecting that is going to just cause some incredible damage on the coast of Mexico?

BOB HENSON: Well, fortunately, it has weakened a little bit as it has approached land. It’s still a very, very powerful hurricane, still a Category 5, as in the most recent observations within the last couple of hours.

Now, the storm surge is going to be pretty significant over a relatively small area. And that’s another blessing with this storm. It’s not a gigantic hurricane. But there will be an area of a few miles where I would expect very, very severe destruction. And, moreover, when it runs into very steep mountains and hillsides just inland, it is going to be dumping gigantic amounts of rain, again, over not a gigantic area, but there could be tremendous amounts of rain along the way. So, mudslides and floods are also going to be a real issue.

WILLIAM BRANGHAM: And then my understanding is that the storm is likely to continue on breaking up somewhat, but then heading into Southern Texas. What are you forecasting for Texas to be looking at?

BOB HENSON: Still pretty stout winds. There will be some high water along the Texas coast, but mainly a lot of rain. Could be six to 12 inches of rain in places like Houston.

And there is an ongoing heavy rain event over Texas already because of a separate storm, so there’s going to be some very, very large local rainfall amounts. And Texas is notorious for October systems that bring in tropical moisture and ex-hurricanes from the Pacific. So this is really something to watch as well.

WILLIAM BRANGHAM: OK.

Bob Henson of Weather Underground, thank you very much.

BOB HENSON: Thank you.

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Bacon, hot dogs and processed meats cause cancer, WHO says

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Barbecue with sausages and hamburger. Photo by JOKER/Erich Haefele/ullstein bild/via Getty Images

Barbecue with sausages and hamburger. Photo by JOKER/Erich Haefele/ullstein bild/via Getty Images

Bacon, sausage and other processed meats are now ranked alongside cigarettes and asbestos as known carcinogens, the World Health Organization announced today. Processed meats cause cancer, and red meat likely causes cancer, the health agency says in a new report.

The new investigation involved 22 scientists who were invited by the WHO’s International Agency for Research on Cancer to assess the association between more than 16 types of cancer and the consumption of red meat and processed meat.

Over the course of seven days in early October, the scientific panel examined more than 800 epidemiological studies from the U.S., Europe, Japan, Australia and elsewhere. The scope covered multiple ethnicities and global diets, according to the report which was published today in the journal Lancet Oncology.

The WHO group “classified consumption of processed meat as ‘carcinogenic to humans’ on the basis of sufficient evidence for colorectal cancer.” Colorectal cancer is the second most lethal form of cancer in the U.S., causing nearly 50,000 deaths per year. Processed meat was also linked to a higher incidence of stomach cancer.

Red meat carries a slightly lower risk, the group says, but is still “probably carcinogenic to humans.” Aside from the “strong mechanistic evidence” related to colorectal cancer, the “consumption of red meat was also positively associated with pancreatic and with prostate cancer.

As a main line of evidence, the group cites one study from 2011, which combed through 28 studies on meat consumption and cancer risk dating back to 1966. That meta analysis found that colorectal cancer risk jumps by 17 percent for every 100 grams (3.5 ounces) of red meat consumed each day. Meanwhile with processed meat, colorectal cancer risk increases by 18 percent for every 50 grams (1.7 ounces) eaten each day.

The International Agency for Research on Cancer keeps a list of compounds or activities with suspected, probable and definitive links to cancer, with each possible item falling into a designated grouping based on whether or not it causes cancer.

Processed meat now falls into “group 1,” meaning it ranks as high as tobacco smoking, the most dangerous variants of human papillomavirus (HPV) and asbestos exposure in terms of causing cancer. Red meat lands in “group 2A” with inorganic lead.

Research in rodents and human tissue shows meat consumption increases the production of chemical compounds, including haem iron and its chemical byproduct N-nitroso-compounds (NOCs). NOCs cause oxidative damage to intestinal tissue that is carcinogenic. Curing meats elevates the levels of NOCs as well as carcinogenic compounds called polycyclic aromatic hydrocarbons. Heating meat leads to the formation of heterocyclic aromatic amines, a known mutagen and cancer-causing agent.

“High-temperature cooking by pan-frying, grilling, or barbecuing generally produces the highest amounts of these chemicals,” the report states.

The new analysis makes a definitive assertion on the connection between eating meat and cancer. In recent years, studies and health policy groups have linked the two activities, but often without explicitly saying meat causes cancer. Take, for example, the American Cancer Society’s position as of this morning:

Because of a wealth of studies linking colon cancer to diets high in red meats (beef, lamb, or liver) and processed meats (hot dogs, bologna, etc.), the Society encourages people to eat more vegetables and fish and less red and processed meats.

As the Guardian reported, the WHO’s new position aligns the views with other health agencies like the World Cancer Research Fund, which has said there is convincing evidence that processed meats cause bowel cancer.

Though a majority of the WHO’s panel agreed to these assessments, the final decision was not unanimous.

The beef industry has been preparing a rebuttal for months to meet the WHO’s announcement, according to The Washington Post:

“We simply don’t think the evidence support any causal link between any red meat and any type of cancer,” Shalene McNeill, executive director of human nutrition at the National Cattlemen’s Beef Association, told The Washington Post.

The post Bacon, hot dogs and processed meats cause cancer, WHO says appeared first on PBS NewsHour.

FAQ: Exactly what processed meat should I avoid, and other questions

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This morning, the World Health Organization revised its health guidelines around the consumption of meat. The report from the WHO’s International Agency for Research on Cancer now labels processed meats as “carcinogenic to humans,” meaning their consumption can cause cancer. The report also classifies red meat as “probably carcinogenic to humans.”

For more on what this finding means for our shopping list and diet choices, we’ve prepared a list of FAQs, as formulated by the collective minds of the PBS NewsHour.

What counts as red meat? What counts as processed meat?

Red meat is any meat that comes from a mammal. That means meat from cows (beef and veal), pigs (pork), sheep (lamb and mutton), horses, goats and bison all count as red meat.

White meats come from fish and poultry. The color difference is dictated by the amount of blood in the tissue, which plays into why red meat is more likely to cause cancer (see below).

Processed meats are any meats that aren’t fresh. People typically think of processed meat as only referring to pork and beef, but this category can also include poultry (chicken, turkey, duck) and fish. A processed meat, according to the panel, has been modified from its natural state, either “through salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation.”

This includes sausages, hot dogs, corned beef, beef jerky, canned meat, meat sauces, lunch meats and bacon.

What does cancer “link” versus cancer “cause” mean?

The word “caused” sounds much more definitive than “linked,” right? Consider the news headlines surrounding this report. Here are two examples:

W.H.O. Report Links Some Cancers With Processed or Red Meat (New York Times)

“Bad Day For Bacon: Processed Red Meats Cause Cancer, WHO Says (NPR)

So which is it?

Technically, meat consumption has been linked to cancer, especially colorectal cancer, for years. It’s a correlation or “link” backed by statistical evidence. Large-scale studies from Europe, Australia, Japan and the U.S. have shown that people who consume more processed and red meat are more likely to develop cancer. Meanwhile, research in the lab has shown scientifically — in rat models and human cells (see below) — how that meat leads to the chemical shifts and genetic mutations that turn healthy cells into cancer cells.

Based on this collective evidence, the WHO panel has concluded today that processed meat can cause cancer, upgrading its threat assessment from correlative to causal.

In contrast, red meat without processing remains a probable cancer-causing agent, because there is less evidence in humans showing that it can spawn cancer.

In a separate Q&A, the WHO wrote:

In the case of red meat, the classification is based on limited evidence from epidemiological studies showing positive associations between eating red meat and developing colorectal cancer as well as strong mechanistic evidence.

Limited evidence means that a positive association has been observed between exposure to the agent and cancer but that other explanations for the observations (technically termed chance, bias, or confounding) could not be ruled out.

How does processed meat compare to smoking and other carcinogens?

The IARC deals in strength of evidence. For this agency, scientific evidence either points to a compound causing cancer in humans or it doesn’t. To classify carcinogenic status, it separates agents into five groups:

Group 1 – carcinogenic to humans

Group 2A – probably carcinogenic to humans

Group 2B – possibly carcinogenic to humans

Group 3- not classifiable

Group 4 – probably not carcinogenic

Of the millions of chemicals in the world, the WHO only only 118 agents fall into group 1. This group includes tobacco smoke, asbestos, aflatoxins (a chemical sometimes found in organic peanut butter), coal emissions from indoor stoves and as of this morning, processed meat.

However, the number of cases caused by each of these agents — or their cancer risk among the general population — varies. That’s because risk, from a public health perspective, is a statistical property. For instance, check out the Cancer Research UK’s breakdown of how smoking and meat consumption contribute to overall cancer rates in the UK:

The risk — the statistical rate in the population — of developing cancer is greater for smoking tobacco than eating processed meat.

Ed Yong’s piece in The Atlantic does a great job of outlining why WHO’s categorical danger versus actual statistical risk can sometimes breed confusion.

My grandpa ate 7 lbs of red meat every day and lived to be 130. Why didn’t he get cancer?

It’s impossible to determine if an individual will get cancer based on a lifestyle choice, whether it’s smoking or eating processed meat. Cancer occurs when a healthy cell acquires enough mutations to start replicating uncontrollably and to spread into new organs away from its site of origin.

Those mutations vary dramatically among the types of cancer (lung, pancreatic, colorectal, etc). They can even differ within a subtype, meaning a pancreatic cancer from one person can be genetically dissimilar than a pancreatic cancer in another. Plus, a malignant tumor in a single individual is constantly evolving, and there is evidence suggesting no two cancer cells in the same tumor are the same.

A cell’s ability to acquire these mutations depends on personal genetics — whether or not you inherited a predisposition from mom and dad — and exposure to compounds that are genotoxic; that is, that can change your DNA.

The IARC is merely concluding today that processed meat can cause cancer if given the chance.

How much processed meat is safe to eat?

On an individual level, it’s hard to say. On a population level, the WHO report cites this epidemiology meta analysis, which examined colorectal cancer studies going back to 1966.

Based on that study, a person who eats 50 grams per day of processed meat has an 18 percent higher chance of developing colorectal cancer. A person who eats 100 grams has a 36 percent higher chance and so on. According to Cancer Research UK, 50 grams per day would be on par with two slices of ham. Two slices of bacon is about 75 grams.

For red meat, cancer risk elevates by 17 percent for every 100 grams per day that is consumed.

When cancer risk levels of both processed meat and red meat were modeled together, the relationship maxed out at 140 grams per day.

Are organically raised meats as dangerous as industrial-produced?

In the context of this WHO report, yes. The danger posed by processed meat and red meat comes from chemical properties inherent to all forms of meat (see below). Organic meat labeling, at least according to the USDA, tackles issues like antibiotic use, hormone use, and access to exercise for domestic animals, which falls outside the scope of the WHO’s report.

What about white meats (chicken and fish) that are processed? Like smoked salmon? What about nitrate-free meats?

The scientific connection between smoked, salted, or cured meats comes down to how these preservation processes influence the chemistry of these foods.

Curing meats involves adding salt, sugar, nitrates like saltpeter or nitrites to preserve foods against bacteria-induced rot and maintain flavor, though the most validated suspects in the cancer drama are nitrites. Enzymes in meat convert nitrites into nitrogen oxide and nitrous acid. Both of which can chemically react with amino acids found in our proteins to form N-nitroso-compounds (NOCs), a class of carcinogenic compounds also sometimes described under the banner nitrosamines. Though saltpeter and other nitrates are a somewhat antiquated way of curing meats, these compounds can become nitrites thanks to chemical reactions mediated by our own cells, by bacteria in our guts, or by bacteria naturally found in meat. NOCs are also spawned by chemical reactions with heme, the red pigment/compound responsible for binding oxygen in blood cells.

“For the red meat, they think it is the HEME iron that is damaging,” said Alice Bender, director of Nutrition Programs at American Institute for Cancer Research.

NOCs can physically bind to genetic material — forming what are called DNA adducts — which can initiate the transformation of healthy cells into a cancer cells.

Grilling, barbecuing, frying, broiling or any form of cooking contributes to the carcinogenic potential of meat due to the accumulation of polycyclic aromatic hydrocarbons (PAHs). How this accumulation happens isn’t completely understood, but this 2005 review paper offers a general overview of the current thinking. In sum, it states that heat breaks down complex organic compounds naturally found in muscle tissue — like fats and sugars — into smaller compounds that react to form PAHs:

At high temperatures, organic compounds are easily fragmented into smaller compounds, mostly free radicals, which may then recombine to form a number of relatively stable PAHs. At temperatures below 400 °C, only small amounts of PAHs are formed. However, the amounts of PAHs increase linearly in the range 400–1000 °C.

Excessive heat can also introduce carcinogens to meat in the form of heterocyclic aromatic amines, which the WHO report abbreviates as HAAs. (The term HCA is also used and means the same thing.) Heterocyclic aromatic amines are formed when naturally-occurring compounds like creatine (found in high quantities in muscle meats), amino acids in protein and sugars become too hot. Like NOCs, heterocyclic aromatic amines are genotoxic and can yield mutations that cause cancer. Here’s what the 2005 review had to say about the formation of heterocyclic aromatic amines:

In general pan-frying and grilling produce high yield of HCAs at cooking temperatures from 200 °C and above, boiling yields little or no HCAs, and deep-fat frying, roasting, and baking procedure give variable yields. Extremely high yield of HCAs have been reported in pan residues….from frying, roasting or baking, while most commercial bouillon cubes contain modest amounts.

PAHs are also thought to be produced when fat and juices from meat hit flames over open grills. These PAHs then float up and “adhere to the surface of meat,” according to the National Cancer Institute.

Smoking introduces carcinogens to meat in the form of polycyclic aromatic hydrocarbons created in the fumes of burning wood or by heat.

These food prep processes increase the amounts of these carcinogenic chemicals in meat, regardless of whether the original animal was a mammal, a bird or a fish. However, the WHO panel primarily made their assessment based on research into processed red meats.

However, given the limited number of studies that have independently examined the influence of different preservation methods on cancer risk among the general population, the WHO can’t state yet if one is worse than another:

Different preservation methods could result in the formation of carcinogens (e.g. N-nitroso compounds), but whether and how much this contributes to the cancer risk is unknown.[Also] there were not enough data for the IARC Working Group to reach a conclusion about whether the way meat is cooked affects the risk of cancer.

Should you give up meat?

Not necessarily. Alice Bender, director of Nutrition Programs at American Institute for Cancer Research, said it’s important to remember the distinction that the WHO report makes between processed meat and red meat.

“Processed meats even in small amounts were increasing risk — a little less than 2 ounces [which is equivalent to] a hot dog or few slices of cold cuts,” Bender told the NewsHour. “For red meat, what is important to keep in mind isn’t so much that you shouldn’t eat it at all, but more the amounts. It’s large amounts that become harmful.”

Oncologist John Schoenfeld of Harvard Medical School agreed.

“There are benefits to red meat, and the findings don’t say that a balanced diet that includes red meat is bad,” Schoenfeld said. “[The report] gives pause to the part of the American diet that is high in meat consumption and red meat. There needs to be broader discussion on [red meat], weighing the benefits and the risks.”

For more of our conversation with John Schoenfeld, check out his interview with PBS NewsHour correspondent William Brangham.

If you have a question, leave it in the comments. We’ll address them ASAP.

Rhana Natour contributed to this report.

Still have questions about Monday’s news from World Health Organization? Join us at 1 p.m. EDT Wednesday for a Twitter chat. Joining us to take your questions will be Alice Bender from the American Institute for Cancer Research (@aicrtweets) and NPR Food and Culture Correspondent, Alison Aubrey (@AubreyNPRFood).

Leave your questions for these experts in the comments below, or on Twitter using the hashtag #NewshourChats.

The post FAQ: Exactly what processed meat should I avoid, and other questions appeared first on PBS NewsHour.

Flying through an icy plume to test a moon’s hospitality

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NewsHour shares web small logoIn our NewsHour Shares series, we show you things that caught our eye recently on the web. What about you? Leave your suggestions in the comments below, or tweet to @NewsHour using #NewsHourShares. We might share it on air.

GWEN IFILL: And now to our NewsHour Shares of the day, something that caught our eye which might be of interest to you, too.

A NASA spacecraft today flew into an icy spray coming off one of Saturn’s moons. The mission? To figure out whether that moon has what they call hydrothermal vents that could support life. This NASA video explains the science behind the theories.

The post Flying through an icy plume to test a moon’s hospitality appeared first on PBS NewsHour.

7 times that science explained aliens

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Actors dressed as martians for their roles in the show 'The Man in the Moon', at the London Palladium in January 1964, walk across Regent Street as two policemen watch them. Photo by Chris Ware/via Getty Images

Actors dressed as martians for their roles in the show “The Man in the Moon,” at the London Palladium in January 1964, walk across Regent Street as two policemen watch them. Photo by Chris Ware via Getty Images

Human interest in unidentified flying objects (UFOs) dates back thousands of years. In the winter of 214 BC, ancient historian Livy reported phantom ships in the skies of Rome. Ancient stargazers believed the neighboring planets in our solar system housed the gods.

Just this month, scientists published data on an unusual spectral pattern coming from the star KIC 8462852 — or Tabby’s Star. In an article, the Atlantic highlighted one scenario that might explain the pattern: the possibility of alien megastructures. Despite follow-up stories describing more logical scenarios — a giant cloud of comets or a jelly bean-shaped star — much of the mainstream fervor focused on possibilities of alien life. Even two days after the Atlantic piece dropped, one of the scientists behind the KIC 8462852 study told Business Insider that the media coverage had gotten “a bit out of hand” and the probability that the signal comes from aliens is “very low.”

“Just to clarify, neither [my colleague] Jason [Wright] or myself … are advocating that it is an alien megastructure, but we also can’t completely rule it out,” Penn State astronomer Kimberly Cartier told Business Insider.

science-wednesday

Smart people believe in aliens too. Renowned Harvard University psychiatrist and Pulitzer-prize winner John E. Mack believed in alien abductions until his death in 2004. (Vanity Fair wrote a great profile of Mack two years ago). Thirty years ago, the famed psychoanalyst C.G. Jung blamed the fear of the unknown, and with it, the human preoccupation with aliens, on our innate search for meaning in places where none exists. In a 2010 essay, clinical psychologist Stephen Diamond described the mental phenomenon this way:

…it is precisely the profoundly mysterious and mythic nature of UFO’s that, like dreams, makes them so psychologically powerful. As with all natural or metaphysical phenomena, once science dissects, analyzes and mechanistically explains such mysteries, their numinous, spiritual, potentially healing power is deadened or lost.

In the spirit of the profoundly mysterious (and Halloween!), PBS NewsHour brings you seven bizarre events originally linked to aliens but then ultimately explained by science. Readers are free to believe what they want, but in these cases, a logical explanation seems more plausible…or at least that’s what THEY want us to tell you.

Phone calls from E.T.

Man dressed in alien costume looking at mobile. Photo by Tara Moore

Man dressed in alien costume looking at mobile. Photo by Tara Moore

In 1967, a 24-year-old astronomer and graduate student named Jocelyn Bell detected rhythmic pulses among data collected by her radio telescope. As the American Physical Society describes:

Working at the Mullard Radio Astronomy Observatory, near Cambridge, starting in 1965 Bell spent about two years building the new telescope, with the help of several other students. Together they hammered over 1,000 posts, strung over 2,000 dipole antennas between them, and connected it all up with 120 miles of wire and cable. The finished telescope covered an area of about four and a half acres.

Within a few weeks Bell noticed something odd in the data, what she called a bit of “scruff.” The signal didn’t look quite like a scintillating source or like manmade interference. She soon realized it was a regular signal, consistently coming from the same patch of sky.

Bell and her mentor Anthony Hewish initially thought the signals were a phone call from an extraterrestrial civilization. But further investigation revealed a previously unknown celestial object: a neutron star. Bell’s initial data had caught focused beams of electromagnetic radiation, which would come to be called pulsars. The work would share the 1974 Nobel Prize in Physics. Bell’s name wasn’t included in the award, but her work inspired the detection protocols for scientific institutes that work in the search for extraterrestrial intelligence.

The SETI Detection Protocols aren’t legally binding, but they dictate how scientists will verify a communication from aliens and the suggested practices for informing the public.

Radio signals represent one of our best bets for spotting extraterrestrial life, and they’ve led to multiple false alarms over the years, such as The Wow! Signal in 1977.


However, a study published this April reported that a search of the 100,000 closest galaxies has come up empty handed with regards to detecting the electromagnetic signals that would indicate advanced technology. That doesn’t eliminate the possibility of alien life using modes of technology beyond our means of detection, but for now, we’re still waiting for E.T.’s call.

Face on Mars

NASA's Viking 1 Orbiter spacecraft shot this image of Mars on July 25, 1976. Can you make out a face from the eroded rock? Image courtesy of NASA/JPL

NASA’s Viking 1 Orbiter spacecraft shot this image of Mars on July 25, 1976. Can you make out a face from the eroded rock? Image courtesy of NASA/JPL

While circling Mars in 1976, NASA’s Viking 1 spacecraft snapped photos of the Red Planet’s landscape. Among the images it beamed back was a picture of a mile-wide landform that resembled a face.

Known as the “Face of Mars,” the image prompted arguments that the site was evidence of an ancient civilization on the planet.

NASA, in its caption for the image, said the mesa-like formation looked like a human head, “giving the illusion of eyes, nose and mouth.” And while the space agency never said the photo captured anything other than a rocky landform jutting from Mars, it left conspiracy theorists wondering whether NASA was hiding something.

But the “face” is not a sign of intelligent Martian life. It’s your brain tricking you. Or, rather, it’s your brain perceiving a meaningful stimulus, like a face, out of everyday objects or sounds. This is a phenomenon called pareidolia, and these moments usually appear in the Weird News section, such as a face in a cliff, the Man in the Moon, or the Virgin Mary on a burnt tortilla.

A 2014 study published in the journal Cortex concluded that the phenomenon was a healthy, common occurrence.

“Most people think you have to be mentally abnormal to see these types of images, so individuals reporting this phenomenon are often ridiculed,” said lead researcher Kang Lee of the University of Toronto. “But our findings suggest that it’s common for people to see non-existent features because human brains are uniquely wired to recognize faces, so that even when there’s only a slight suggestion of facial features the brain automatically interprets it as a face.”

The study added that the brain’s ability to glean faces from ambiguous information is “highly adaptive” because of the “supreme importance of faces in our social life and the high cost resulting from failure to detect a true face.”

This is a hi-res image of the same "face" that NASA captured in 1976. There's not a human face there anymore. Image courtesy of NASA/JPL/University of Arizona

This is a hi-res image of the same “face” that NASA captured in 1976. There’s not a human face there anymore. Image courtesy of NASA/JPL/University of Arizona

NASA, equipped with modern technology, reshot the “Face of Mars” in 1998. In the higher resolution, the face disappeared. NASA was right in its original caption: The “face” is an illusion.

Alien engineering

Tourists ride camels in front of Giza pyramids in 2006. Humans were perfectly capable of building these ancient wonders. Photo by Goran Tomasevic/Reuters

Tourists ride camels in front of Giza pyramids in 2006. Humans were perfectly capable of building these ancient wonders. Photo by Goran Tomasevic/Reuters

The Great Pyramid of Giza, one of the original Seven Wonders, is such a paragon of human achievement, that people have questioned whether the ancient, man-made structure was actually constructed with the help of aliens.

But give the ancient Egyptians some credit.

According to architect Jean-Pierre Houdin and Egyptologist Bob Brier, the ancient Egyptians hauled 2.5 ton limestone blocks using an internal ramp that snaked up the pyramid like a parking garage.

In 1986, a French team failed to find any hidden spaces in the Giza pyramid that suggested an internal ramp. But, as documented in this National Geographic TV special, one of the French researchers met with Houdin 15 years later to reveal a diagram left out of that 1986 study. The diagram showed a hollow spiral shape within the pyramid that appeared to support Houdin’s theory.

Despite the mounting evidence to the contrary, people also continue to believe that primitive cultures were not able to erect pyramids in Nigeria, China or Indonesia without extraterrestrial assistance.

“It’s these suggestions that are really denigrating the people whose names, bodies, family relationships, tools and bakeries we actually find,” Egyptologist Mark Lehner, who studied the pyramids for years and wrote “The Complete Pyramids,” told NOVA in 1997.

“Everything that I have found convinces me more and more that indeed it is this society that built the Sphinx and the Pyramids,” he said. “Every time I go back to Giza, my respect increases for those people and that society, that they could do it.”

Flying Saucers

Nevada Governor Bob Miller presides over the unveiling of a new road sign for Nevada State Highway 375 on April 18, 1996, about 150 miles north of Las Vegas. The highway has been the location for numerous UFO sightings, possibly related to the close proximity of the secret U.S. airbase Area 51. Photo by Reuters

Nevada Governor Bob Miller presides over the unveiling of a new road sign for Nevada State Highway 375 on April 18, 1996, about 150 miles north of Las Vegas. The highway has been the location for numerous UFO sightings, possibly related to the close proximity of the secret U.S. airbase Area 51. Photo by Reuters

“I have no doubt that UFOs exist,” science writer and longtime investigator of unusual phenomena Benjamin Radford wrote for Space.com.

That’s because an Unidentified Flying Object is any vision in the sky that a person’s mind can’t immediately explain. But that doesn’t mean it’s piloted by alien life. The Earth’s atmosphere is bombarded by roughly 100 tons of space rock every day, and who hasn’t seen a saucer-shaped cloud in their lifetime?

The origins of the term “flying saucer” can be traced to a single, misquoted source.

The Eastern Oregonian reported on June 24, 1947, that Idaho pilot Kenneth Arnold saw nine “flying objects” or flashes that flew past Mount Rainier, according to this Atlantic report. But when Arnold’s story got picked up by other news outlets, the description of the objects morphed into “flying saucers.”

Years later, Arnold said he had told the Oregonian that the objects “flew like a saucer would if you skipped it across the water.” In other words, Arnold said he used “saucer” to describe the movement — and not the shape — of the UFOs.
In a 1950 interview with journalist Edward R. Murrow, Arnold repeated his claim that reporters had misquoted him.

“[W]hen I told the press, they misquoted me, and in the excitement of it all, one newspaper and another one got it as ensnarled up that nobody knew just exactly what they were talking about, I guess,” he told Murrow.

Kenneth Arnold submitted this letter, complete with rough sketches of the flying objects he saw, to the Army Air Force on July 12, 1947. Image courtesy of Wikimedia Commons

Kenneth Arnold submitted this letter, complete with rough sketches of the flying objects he saw, to the Army Air Force on July 12, 1947. Image courtesy of Wikimedia Commons

Either way, the era of UFO sightings had begun, and the flying saucer became a mainstay in science fiction.

Only weeks later, rancher William Brazel discovered a wreckage near Roswell, New Mexico and assumed a flying saucer had crashed. That Roswell incident would become America’s best known experience with UFOs. On July 8, military officials claimed the debris came from a weather balloon, but decades later the incident would resurface as a centerpiece in a government alien cover-up, as detailed by the Committee of Skeptical Inquiry.

The government was covering up the true reason for the wreckage, but it wasn’t aliens. The real reason involved Project MOGUL, a spy balloon built to detect long-range soundwaves from possible Soviet nuclear weapons.

Researchers believe the Cold War continued to fuel UFO hysteria, as the Guardian reported in 2002:

Many of the early UFO sightings were seemingly confirmed by Britain’s fledgling radar system, often scrambling fighter planes into the sky to investigate sightings. But, as the new technology improved, the number of incidents appearing on radar quickly dwindled to zero. ‘That cannot be a coincidence. Those early confirmations were just a product of a primitive radar system,’ Clarke said.

Missiles continue to be identified as UFOs, as do things like Chinese lanterns, oddly-shaped clouds, lightning sprites and the planet Venus.

There should be an embedded item here. Please visit the original post to view it.

UFO sightings often involve hole-punch clouds like this one, which typically occur when an airplane creates small snowstorm while passing through a cloud.

Crop circles

A crop circle appeared in London's Kew Gardens on Sept. 19, 2002. Photo by Reuters

A crop circle appeared in London’s Kew Gardens on Sept. 19, 2002. Photo by Reuters

No one disputes that crop circles are real. But who created them?

Appearing first in the late 1970s in the English countryside, conspiracies often pointed to aliens sending messages to humans in fields of flattened crops. Instead, it was an Earthbound hoax.

After years of crop circle reports in southern England in the 1980s, crop circles began popping up in Canada and Australia too. But then, two pranksters in their 60s came forward in 1991 as the originators of a massive hoax.

WHEN David Chorley and Doug Bower told the London tabloid Today in 1991 that they made the circular designs overnight by using wooden planks, a ball of string, and a piece of wire attached to a baseball cap that worked as a sighting device.

In the video below, Chorley and Bower explained how they could make a circle 80 to 90 feet wide in 10 minutes, adding that they didn’t see news reports of their crop circles until three years after their initial creation.

Video by YouTube user mdftrasher

The hoaxers said they decided to confess when Bower’s wife became suspicious of the high mileage on the couple’s car. She suspected her husband was having an affair.Bower explained that he and Chorley flattened crops in southern England as many as 30 times a year. And the crop circles spotted outside their home country? That was the work of copycats.

The confessions, however, didn’t dissuade M. Night Shyamalan from featuring the crop circles in his 2002 movie “Signs.”

Area 51

Area 51 border and warning sign stating that "photography is prohibited." Photo by Flickr user X 51

Area 51 border and warning sign stating that “photography is prohibited.” Photo by Flickr user X 51

For decades, conspiracy theories painted the hyper-exclusive, top secret military base near Groom Lake, Nev., as a storage bin for U.S. scientists to study little green men and their alien spacecraft.

Then in 2013, the CIA, prompted by a public records request by the National Security Archive, declassified a 400-page 1992 document that specifically acknowledged the existence of Area 51.

Or, as one UFO enthusiast told NBS News: “They say Area 51 is real? Duh!”

In fact, Annie Jacobsen, author of “Area 51: An Uncensored History of America’s Top Secret Military Base,” told National Geographic that only one page of the declassified report was new information. That one page literally put Area 51 on a map.

But a lot remains unknown about the remote government facility. The declassified report goes on about the U-2 spy planes used during the Cold War that were being tested at the site. There’s no mention of Roswell aliens, spaceships and the like.

The report, however, does mention UFOs, but only that the U-2 planes “led to an unexpected side effect — a tremendous increase in reports of unidentified flying objects, UFOs.”

Alien Abductions

Alien abduction warning signs are posted in the AlienVault booth during the Black Hat USA 2015 cybersecurity conference in Las Vegas. Photo by Steve Marcus/Reuters

Alien abduction warning signs are posted in the AlienVault booth during the Black Hat USA 2015 cybersecurity conference in Las Vegas. Photo by Steve Marcus/Reuters

Alien abductions have been reported across the globe, and these claims may have a neuroscientific explanation.

Our memories are prone to change and susceptible to the inclusion of false facts, which is known as false memory recall. False memory recall is common. This mental behavior can muck up eyewitness testimony and gets worse as we age. Just within the last two years, scientists have shown that they can artificially implant a false memory into the brains of mice.

A 2003 Harvard study showed that people who claim alien abductions are more susceptible to false memories. Plus their memory recall is often so strong and so physically disturbing that it is comparable to war veterans remembering battle.

Sleep paralysis is a possible explanation for how these memories form in the first place. Sleep paralysis occurs when someone’s brain wakes up before the rest of the body. During REM sleep, the body releases a chemical that prevents it from moving while you sleep. During a sleep paralysis episode, a person can become conscious before the chemical wears off. Cue the monsters that emerge from the dreams that occur somewhere in that accidental space.

“Sleep paralysis is common and no more indicative of mental illness than a hiccup, the researchers point out. But when the hallucination and paralysis occur together, many people find the combination frightening, and they attempt to find a meaning in it,” William Cromie wrote in the Harvard Gazette.

According to a 2011 study by Pennsylvania State University, as many as 7.6 percent of the general population will experience at least one instance of sleep paralysis in their lifetime.

When falling asleep or waking up, people have reported faceless shadowy figures or a dark presence in their bedrooms. Horrifically, these harbingers of doom would sometimes advance toward them while they’re unable to move.

While it’s not the work of supernatural beings, it is a brain glitch that produces some serious fuel for nightmares.

The post 7 times that science explained aliens appeared first on PBS NewsHour.






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