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Yes, Vaccines Work [Infographic]

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Some numbers before and after the introduction of common childhood vaccines

Do vaccines really work? Over the past decade, some parents in the U.S., Canada and Europe have started refusing to give their kids the recommended childhood vaccinations. They worry about safety, believing vaccines may cause autism or other disorders. Denial that the vaccines have any benefit at all has been a part of this particular type of refusal. (Parents in other parts of the world oppose vaccines for other reasons.)

Although no vaccines are 100 percent effective, they can have a big impact on the health of a population. Toronto's public health department put together this visual of the rates at which Canadians got different infections before and after the advent of some common childhood vaccines.

You can learn more about studies of vaccine safety and efficacy with Popular Science's new guide.

Impact of Vaccines in Canada

[Visually]

    



Big Pic: Goodnight Moons

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Two Moons

NASA/JPL-Caltech/Space Science Institute

Cassini snaps two of Saturn's moons through the rings

NASA's Cassini spacecraft has been hanging out near Saturn since 2004, studying the planet's icy moons. In this image taken in mid-May, Mimas and Pandora, two of Saturn's 62 confirmed moons, hang out around 730,000 miles away from Cassini's narrow-angle camera.

Little Pandora doesn't have enough gravitational pull to whip itself into a spherical shape, which is why it kind of looks like a jelly bean. Scientists think its shape could be a clue as to how Saturn's rings formed. And though it looks huge in comparison, Mimas isn't so large itself. It's the smallest astronomical object that's been rounded by its own gravity.

Cassini has had its mission extended twice since it first launched in 1997. Its current mission, the Solstice Mission, is mainly focused on studying Saturn's larger moons, Titan and Enceladus.

[NASA]

    


Why People Love Tipping Waiters

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Mazzini's

By Peggy Bacon

Smithsonian Institution

As an economic phenomenon, tipping is really weird. As a psychological phenomenon, it's something else entirely.

When the Linkery, a small San Diego restaurant, shuttered its doors this summer, it ended a fascinating social experiment. The Linkery had instituted a standard 18 percent service charge in lieu of tips, and had refused to accept anything on top of that. Meanwhile, its sister restaurant down the street, El Take It Easy, operated under a traditional tipping model. The upshot, as owner Jay Porter points out in a series on his blog called "Observations From A Tipless Restaurant": people totally resented the Linkery for taking away the power to tip. ("You, sir are a douche," read an email from one unhappy patron.) It's a phenomenon academic research has borne out. But why? Why do we love tipping waiters?

First, the argument for banishing tips: Many states have laws allowing waitstaff to be paid as little as $2 an hour because they will make up the revenue in tips, and prohibiting tips from being distributed among members of the kitchen staff. Ofer Azar, an economist who has written extensively about tipping, explains the cyclical phenomenon this way: "[P]eople start to tip certain workers, the employers of these workers reduce their wages (they can do so because the worker receives part of his reservation wage from tips), people feel more obligated to tip because they know that the worker depends on tips to complement his wages, more people tip and possibly each tip becomes higher, and so on." No wonder some, like Porter, just want to take tips out of the equation.

Problem is, people like tipping. Which is weird, because it doesn't make much economic sense. Tips are paid after the service has been provided, and the quality can't be changed after the fact. People tip even when they aren't planning on returning to the restaurant, so the underlying motivations for tipping can't be all about ensuring a good experience in the future.

A 2010 paper Azar published in Applied Economics found that rather than being a strategic move to ensure quality service, tipping is largely the result of psychological motivations--like feeling social pressure, or wanting to preserve a self-image of generosity. Another study found that tipping is a risk sharing method between a waiter and a customer, ensuring people don't lose too much money on food that could be terrible: "when the meal is unusually bad the diner can choose to withhold a tip and reduce the loss of utility that would otherwise occur," the researcher theorized.

The preference to tip isn't exclusive to Americans. In a study comparing tipping in the U.S. and Israel, Azar found that people in both countries would rather tip than pay service charges, despite the fact that people usually tip more than the fixed amount of a service charge. There's not a definitive conclusion as to why, though one reason might be that "a person who tips because he wants to show his gratitude, will no longer be able to show gratitude when the tip becomes a compulsory service charge." The study found people who tip to show gratitude were 14 percent more likely to prefer tipping.

Porter, for his part, thinks diners' preference for tipping has something to do with power. In his first post, he presents this gem of an observation:

A certain small number of very vocal men (and it was always men) resented that we were not letting them try to exercise additional control over our team members. This was true even though compelling research has shown that servers do not adjust quality of service as a result of tips; instead the idea that the restaurant was not offering our servers up as objects of control, was heresy. For these people, the primary service they wanted from the restaurant was the opportunity to pay for favors from the server - much like the patron at a strip club pays the club for the opportunity to dangle bills in front a dancer for individual attention.

There's some research to back up his idea of tipping being a type of control. As sociologist Zachary Brewster writes in a paper in the International Journal of Hospitality Management, "As a result of management's limited ability to directly control the behaviors of servers at the point of service delivery they attempt to do so indirectly by delegating control responsibilities to consumers who leave tips in accordance with the quality of service they received." Servers have a certain amount of autonomy in tailoring their service to the customer, but in turn, the customer controls the situation through tipping. The study found that tipping can lead to better service, if the waiter perceived that the customers would tip well. The servers made strategic decisions about who to allocate better service to based on their prediction of how certain groups would tip.

To add extra complexity to the tipping game, a new study, out this month in the Journal of Consumer Behaviour, suggests that when servers express gratitude, it can backfire. Though previous work found that adding a "thank you" to the back of a receipt could increase tips, the latest research found that tip percentages actually fell when wait staff added personalized messages to receipts, like drawing smile faces or writing "thank you."

"If a typical server's customers spent a total of $2,000 over the course of one work week, then our results suggest that servers who personalize bills would lose $42 in tips if their service exceeded expectations and $59 in tips if their service failed to exceed expectations," the researchers write.

It seems like you just can't win when it comes to tips.

[Jay Porter]

    


10 Robots That Are Way More Athletic Than You

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Oh, you're a pro swimmer? Well, Swumanoid's an Olympian.

Maybe you're really athletic. You're, say, a great basketball player, or you can do those fingertip push-ups the heroes do in kung-fu movies. That's great. But whatever you can do, our future machine-overlords can do better. For example...

GYMNASTICS


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You can either start training to do gymnastics when you're six years old, or you can just have this robot, created by YouTube user Hinamitetu, do all the hard work for you. Here, you can witness it do a quadruple-backflip--and stick the landing. Offscreen: robot judges holding up scorecards that all say 10.
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BALANCING


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You could spend years walking around with books on your head but the second someone hits you with a wrecking ball, you'll fall over. (Happens every day.) Not so with ATLAS, Boston Dynamics' humanoid robot with impressive poise.
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RUNNING


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If you're not as fast as Usain Bolt, then you're not as fast as this other Boston Dynamics creation, the Cheetah Robot, which can dash along at an impressive 28.3 mph, besting Bolt's 27.78 mph record.
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WEIGHT LIFTING


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FANUC Robotics America created the M-2000iA robot to pick up heavy stuff. It is very good at picking up heavy stuff. Like, for example, this 2,550-pound train wheel--basically, more than a Volkswagen Beetle. Plus, the robot lifts the wheel over the equivalent of its head.
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JUMPING


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The Sand Flea took home one of our Best of What's New awards for being able to jump really freakin' high--up to 26 feet in the air. Impressive. Also, in addition to jumping on to buildings, you can see the robot has a proclivity for jumping off buildings, which generally doesn't turn out well for people.
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BASKETBALL


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Yes, this robot seal thing created by Taiwanese researchers is a little weird, but you won't be saying that when its sinking 99 percent of all shots on you. (Only within a three-meter range, but you try to do that dressed in a seal costume.) You can even move the basket on it, and it'll still ball like a pro.
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DEXTERITY


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You know that game ex-cons play in movies, where they stab the knife on a table in between their fingers? ABB Robotics' industrial 'bots would be very good at that game if they were stuck in robot jail or something. Here it navigates a pin between Fanta cans, consistently staying within a 30-micron range.
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BASEBALL


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Researchers built an entire 100,000-neuron "brain" to make this robot, which expertly swats away ball after ball. If the robot misses a swing, the faux-neurons fire in a different sequence until they begin hitting the ball every time. Even in the robot league, 1.000 is impressive.
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SWIMMING


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Swumanoid is a 12-pound, three-foot-tall Olympian. Researchers in Japan used a 3-D scanner to model the body of a former Japanese Olympic swimmer, then made the robot based on the scan. (Swumanoid is half-scale. There was not a three-foot-tall world-class swimmer you somehow failed to hear about.) The 'bot can't break record speeds--at half-size it travels at a relatively sluggish .64 meters per second--but that's mighty impressive for such a small robot. Plus: its freestyle form is consistently flawless.
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SOCCER (AGAINST LIONEL MESSI)


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Ah, at last. A showdown between robot and human athlete. Barcelona superstar soccer player Lionel Messi went toe-to-toe with a robot goalie, John Henry-style, for a Japanese game show. After two failed attempts [WEIRD JAPANESE GAME SHOW SPOILER ALERT] Messi scores. So there's hope yet for the athletic future of humanity.

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The Goods: August 2013's Hottest Gadgets

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Silencer

The Chrome extension Silencer blocks spoilers from social networks by filtering out posts with words that could ruin a TV episode or sporting event. A user enters a keyword or chooses a list; for example, the Arrested Development list weeds out 38 trigger words. Free

Courtesy Silencer

A spoiler-blocking web extension, Nerf's farthest-firing gun, and more


    


How Realistic Is The Sci-Fi Space Thriller 'Europa Report'?

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Europa Report

Wayfare Entertainment

We chat with Kevin Hand, an astrobiologist who consulted on the film, about realism in space thrillers, why actors are better than robots, and more.

It's rare that a great space movie breaks the Hollywood traditions of big budgets, blatant abuse of physics, over-the-top special effects, factitious characters, and hokey one-liners. Successfully straddling the line between fact and reality, as these space oddities strive to do, is extraordinarily difficult.

Stanley Kubrick and Arthur C. Clarke's 2001: A Space Odyssey easily sets the highest standard in this department. However, we recently screened the new movie Europa Report, and were taken aback by its respect for audience intelligence while still offering a thrilling, edge-of-your-seat story [watch the trailer below]. It's clear director Sebastián Cordero and writer Philip Gelatt did their science homework. Their characters behave like real people on a believable mission to search for life on Europa -- an icy moon of Jupiter that astrobiologists yearn to explore.

Here, we pick the brain of Kevin Hand, an astrobiologist and expert on Europa at NASA's Jet Propulsion laboratory in Pasadena, Calif., and one of the film's volunteer science consultants, on how to create a truly realistic space film that won't bore viewers to tears.

Spoiler alert: Key scenes and plot elements are mentioned here, so bookmark this article if you want to watch the movie first.

How and why did you get involved with Europa Report?

Through the Science & Entertainment Exchange. They connect moviemakers with scientists, catalyze those relationships, and, if one works, we go off on our own to consult.

The leadership and writing team for Europa Report was very keen on learning as much as they could about the moon. They wanted a compelling story that adhered to science to make it believable. They constantly emailed and called us to talk through ideas and see if they had gotten it right. To me it seemed refreshingly out of the ordinary.

Anyway, both myself and my colleague, Steve Vance, had a pretty heavy hand in making sure they got some of the big-picture brushstrokes correct.

What concerned you the most?

Something we talked about early on was the feasibility of getting humans to Europa. It's an icy moon of Jupiter, and not a desirable place to be. The surface is incredibly cold and bathed in dangerous radiation -- and it would take a very long time to get there. But it could still happen.

Filmmakers are always about putting the story first. We here at JPL think robots make great characters, but it often takes human actors to make a film work. So that was something I had to get over.

Once we got past getting to Europa, we played around with what it would be like on the surface. They listened to us, and I was quite impressed with the final product's attention to detail, including, for example, how harsh the radiation environment is and how it'd manifest itself. They committed some errors here and there -- a wrong turn of phrase or incorrect geological term -- but overall, I was impressed.

Where does the nasty radiation come from?

The magnetic field of Jupiter has all of these electrons, protons, and ions stuck within it. So as Jupiter rotates, Europa is kind of like a slow jogger in a windy rainstorm. The wind -- the magnetic field in this analogy -- comes sweeping from behind and throws raindrops (the particles) on the back side of the jogger (Europa).

Jupiter has a 10-hour rotation and 3.5 Earth days for Europa, which makes the same face always showing to Jupiter. So the backside is always exposed to this intense electromagnetic radiation. The leading hemisphere, meanwhile, we think gets less radiation. Even on the front side, there's a fair amount of radiation -- broadly equivalent to Earth's upper atmosphere during a solar storm, which is a pretty dangerous amount. They did get that right.

Each second on the surface, without any shielding, would be about the dose of a chest CT scan. Even with shielding, you would get severe radiation poisoning in about an hour that might be fatal.

Landing on Europa is key to this movie. How good was their descent vehicle?

Well, the engineering sequence that they present is as well-fleshed out as any manned mission to Europa has ever been -- and of course there haven't been any. They had lot of creative license, considering a human mission to Europa is nowhere on the books.

The renderings of Europa's surface certainly looked incredible, but I'm curious what you thought about them.

We worked in considerable depth with the artist both on the landing region and the small canyon in which they land. What they came up with was wonderful. I think they really gave the viewer a sense of what it'd be like to stand on surface of Europa.

My motivation here was to open up a window into this beautiful, fascinating world. That, to me, is the first step in getting an audience fascinated with a place like this, and reeling them into the possibility and excitement of exploring it -- even though I think robots are a better way. It seems like such a small thing, but can have a big influence.

What science fiction influenced your career as an astrobiologist?

Definitely Close Encounters of the Third Kind. It had the dual effect of captivating and scaring the heck out of me as a young kid. And then of course the kinder, gentler ET came along and was a heavy influence on my boyhood fascination with extraterrestrial beings. The fascination with microbial life came later, once I gained a scientific appreciation for the variability of life.

I also read Arthur C. Clarke in high school and have watched [2001: A Space Odyssey] and [2010: Odyssey Two] over and over again.

The movie gets really interesting when they get close to a weak point in Europa's icy crust. Do those actually exist?

We can't be certain if Europa is still geologically active today, or has just been in the recent past. It could be that the fissures we see on the surface are relics from a million or 10 million years ago. We have no smoking gun like we do with Enceladus [a moon of Saturn]; it's spraying water and other material into space, and the Cassini spacecraft flew through that and analyzed it. We don't have anything like that for Europa.

One thing we do have is remote observations of surface chemistry. We think Europa is recombining salts from the ocean below with ions spewed out by its neighboring moon, Io. We also know that Europa's surface has been active within the recent past -- hundreds of thousands or millions of years ago. That is a short timeframe, geologically speaking. We think the surface of Europa is the same age as its seafloor, and few impact craters tell that story.

Still, we've only really had two spacecraft visit Europa, and barely: The Voyagers in the late 1970s and early 1980s, and Galileo, which launched in 1989 and orbited Jupiter and performed flybys. Here we are, in 2013, and we have yet to go back to Europa -- even though it's an incredibly compelling world in which to search for life beyond Earth.

There's some of that search in the movie -- a female scientist scoops up colored ice. What did you think of that sequence?

The sample she got was on the surface, and she determined it was living right away. We don't expect to find anything alive on surface of Europa. The harsh cold and radiation make that a losing proposition. That's not the way it'd happen. We could, however, find complex organic molecules or maybe dead, frozen life on the surface.

And what about the thing under the ice?

To have something that interesting right below the surface is not realistic. The filmmakers took some license with how thick the ice is. Our knowledge of the ice's thickness is more of a global average, but it's still a few kilometers to tens of kilometers thick.

That said, I liked how they ended it with just enough to intrigue you about what they found, but not go over the top with it all. I found the ending refreshing. That kind of discovery is my dream of dreams.

How would you rate the overall scientific accuracy of the movie?

There are a few mistakes here and there, but I have to say it's well above average in terms of scientific accuracy. I love that this sort of documentary-from-the-future way of framing the movie. The Europa Report is singularly believable film, from the conflicts within and among characters, to the premise of the mission and what it might look like.

There's a balance the writers and directors tried to achieve: They wanted enough realism to make it believable, but needed to advance the stories and characters to make the movie enjoyable. I thought they did a good job of developing characters you could get emotionally invested in. They were multidimensional, and I could identify with them. That's hard to do.

At the end of the day, though, I'm just thrilled anyone is making a movie about Europa. It's such a fascinating yet little-known world out there in our Solar System. I hope this movie brings a little bit of spotlight onto the moon.

The film premieres today in New York, and Popular Science will be on hand to moderate a panel with the filmmakers. Stay tuned on PopularScience.com for a video recap.

    


A 3-D Printer Can Pay For Itself In Less Than A Year

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Makerbot Bot Farm

Dan Nosowitz

Routine questions for the makers of desktop 3-D printers: "what do you do with this thing?" and "why would you want one?" A study from Michigan Technical University answered that with some math: the researchers found that you could recoup the up-front cost of a 3-D printer in less than a year.

The researchers used a RepRap printer and printed about 20 household items, from shower rings to iPhone cases, and found that the total cost of material swas about $18. (It's a bit of a change from this cool stuff.) The "lowest retail cost we could find for the same items online was $312 and the highest was $1,943," said Joshua Pierce, one of the researchers. The study projected that a 3-D printer could could save consumers between $300 and $2,000 a year.

They're assuming that you're using one of the cheapest RepRap printers, rather than a RepRap-based printer like the MakerBot that can cost a few thousand dollars, and also assuming that you have a lot of need for plastic items, and also assuming that you like the quality of items printed with this kind of printer. With a 100-micron resolution, you're getting a rougher sort of product than you'd buy from Amazon; you can see the layers, for example. But the benefit is that you can modify the items to your preference, with different colors or patterns or sizes.

"The unavoidable conclusion from this study is that the RepRap [3D printers] is an economically attractive investment for the average U.S. household already," concludes the paper, published in Mechatronics.

[via Slashdot]

    


Learn Japanese Calligraphy From A Robot

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Calligraphy Robot

Screenshot via YouTube

Technology could preserve the waning skill.

As smartphones and computers become more prevalent in people's daily lives, many in Japan fear that the ancient art of shodo, Japanese brush writing, will die out. In a 2012 survey by Japan's Ministry of Education, more than 60 percent of respondents said they believed they were losing the ability to write kanji characters, one of the three types of script used in modern Japanese writing.

Seiichiro Katsura, a professor at Keio University in Tokyo, aims to preserve the classic art form with the help of a deft robotic arm programmed with the skills of a master calligrapher, 90-year-old Juho Sado. It guides Japanese children in the correct calligraphy techniques, helping them learn the right wrist movements, angles and brush strokes orders.

"When you take the brush, it's as if the master himself is holding your hand and guiding you," Ayaka Matsui, one of Katsura's assistants, told AFP.

Katsura told the news service he hopes similar technology could one day help people learn mechanical or surgical techniques.

[Phys.org]

    



The Simplest Periodic Table We've Ever Seen

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The Periodic Table of the Elements, by electronic structure

Alison Haigh

No numbers, just dots

In this beautiful, easy-to-read periodic table, created by London-based graphic designer Alison Haigh, each element is represented by a visualization of its electronic structure, rather than by numbers and letters.

The dots each represent electrons-so, hydrogen, which has an atomic number of 1, is the single dot in the upper lefthand corner.

Here is the radioactive synthetic element Copernicium, which has an atomic number of 112 (and was first created in 1996 by scientists in Germany):

You can purchase a print of this periodic table here. Or, check out the periodic table of humanity's worst vices.

    


New Evidence: When Did Humanity's Last Common Male And Female Ancestors Live?

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Sardinian Fishermen

Two men go fishing the traditional way off the coast of the Italian island of Sardinia. One new study of human ancestry used the genetic diversity of Sardinian men to determine the dates of the last common male ancestor of modern humans.

Photo by Gianluca Dedola

Sadly, Adam and Eve probably didn't date each other.

Hundreds of thousands of years ago-when people still lived in small hunter-gatherer bands, when it's not even clear they were totally anatomically modern (though they probably were)-something happened in the human genome.

Somewhere in Africa, a man carried a Y chromosome that would turn out to be the only surviving Y chromosome in humans today. This man lived around plenty of other people, perhaps with their own Y chromosomes, but chance whittled away his peers' contributions until only his was left.

In a totally independent event, a woman carried mitochondria-tiny structures contained inside cells-that would become the only mitochondria people have today. Like the Y-man, she lived around other people, but over thousands of years, luck struck down all others' mitochondria save her own.

Now, in a pair of newpapers published today, two separate research groups say they've determined the dates during which the last common Y-chromosome ancestor lived. One of the groups also came up with dates for when the last common mitochondrial ancestor lived. The dates vary from previous estimates-and from each other-which is sure to set off healthy debates about when these seminal genetic events occurred.

As geneticists improve their understanding of these last common ancestors, the times they find may help scientists better understand when other important events in human evolution occurred, such as the spread of people from Africa. Where the archaeological record is sparse or conflicted, genetics can help, says Brenna Henn, who researches genetics and human evolution at Stony Brook University in New York. Henn was part of one of the two teams publishing today.

One of the teams, led by Paolo Francalacci of the University of Sassari in Italy, determined that everybody's last common male ancestor lived 180,000 to 200,000 years ago. Another team, led by Carlos Bustamante of Stanford University, concluded that the modern human Y chromosome first appeared on Earth 120,000 to 156,000 years ago. Bustamante also found that modern mitochondria appeared in people beginning 99,000 to 148,000 years ago. (Henn worked with Bustamante's team.)

Both Francalacci and Bustamante graciously say that their estimates for the Y chromosome are not that far apart from each other. Researchers not involved in their work more readily acknowledge the two's discrepancy. "It's not a big difference," University of Arizona anthropologist Michael Hammer tells Popular Science. "But it is different." Hammer has long worked on dating Y chromosomes and mitochondria.

Previous estimates of the date of the last common Y ancestor varied from about 50,000 years ago to 340,000 years ago, a broad range. Previous estimates of when the last common mitochondrial ancestor live were more precise, ranging from 150,000 to 240,000 years ago.

One big advantage that Bustamante and Francalacci had was that they worked with much more of the Y chromosome than anybody had before them. Time and technology have made DNA sequencing more affordable, with lots of consequences. One of them is having much more DNA available for studies like this.

"It's great to see large-scale sequencing being applied to the Y chromosome," says Chris Tyler-Smith, who studies genetics and human evolution with the U.K.'s Wellcome Trust. "I think this is the future of Y chromosome study."

* * *

Archaeologists look at unearthed ancient artifacts, while anthropologists often work with fossils to help them reconstruct prehistory. Geneticists interested in human evolution, however, have only modern DNA to look at. Francalacci, Bustamante and others like them make their last common ancestor estimates by gathering DNA samples from men and women walking around today.

The keys are two parts of the genome, the Y chromosome-which only men have, and only men pass on-and the mitochondrial DNA-which everybody has, but only women pass on. (So if you're a man, all your mitochondrial DNA come from your mother. Your sister's mitochondrial DNA also come from your mom.)

These two parts of the human DNA are special because they're the only parts that children inherit from their parents with perfect accuracy. Every other part of the DNA gets remixed and reshuffled in every new baby, which is how you can have your mom's hair and your dad's eyes, while your sister got Mom's eyes, Dad's hair and Dad's flat ears.

The Y chromosome's and the mitochondria's straightforward inheritance patterns make them comparatively easy to trace through time, so geneticists often focus on them. Because the two bits had to come from a man and a woman, respectively, the people who gave all modern humans these parts of their genome are often called something like the "Y-chromosome Adam" and the "mitochondrial Eve," which is a fun way to think about them. However, it's vanishingly unlikely the two ever met each other and mated, and they didn't live in an unpeopled Eden.

* * *

Now, it's been a long time since this Adam and Eve walked the Earth, so the inheritance they left us has changed over time. Theoretically, fathers pass on their Y chromosomes with perfect accuracy to their sons, and mothers pass on their mitochondrial DNA with perfect accuracy to all their children. In reality, mistakes happen. Over time, random mutations work their way in.

Geneticists theorize that such mutations occur at a regular rate, with X number of mutations spontaneously appearing in the genome over Y number of years. So when geneticists make their estimates of last common ancestors, they take DNA samples from a large number of people, see how different those people's DNA are from each other, and then use some outside information to help them calculate how long it should have taken for those differences to arise. "It's basically distance equals rate times time," says David Poznik, the Stanford University scientist who did much of the dating work in his the paper with Bustamante.

Different geneticists calculate this rate of change differently. There's no standard way to do it. That's why people have come up with different times for the last common Y-chromosome and mitochondrial ancestors.

Francalacci and Bustamante used a relatively new way of calculating the rate of DNA change. They used dates determined by archaeology as mile markers. Francalacci and his lab, for example, used the spread of people over the Italian island of Sardinia 7,700 years ago as their mile marker. They sampled DNA from 1,204 Sardinian men, calculated how different those men's Y chromosomes were from each other, and then calculated the mutation rate required for Sardinian diversity to have arisen over 7,700 years. Bustamante and his colleagues did something similar with the peopling of the Americas 15,000 years ago.

Others calculate the human mutation rate in other ways, including dating from the time humans and chimpanzees branched away from each other and simply checking the mutation rate between modern parents and their children. Every researcher, of course, argues the way he or she has chosen is best; we won't get into that. "The diversity of views and results is healthy," Tyler-Smith says. "It's a really exciting time in the field."

Suffice it to say this isn't the last word on when the Y-chromosome Adam and the mitochondrial Eve lived. Given the range in recent estimates, it's not even necessarily true that the two folks were anatomically modern, which is kind of cool to think about. But as long as modern humans carry in them these relatively unchanged pieces of DNA, the keys are there for us to find out.

    


This Must Be The Best Ruler Ever Invented

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It looks pityingly on rulers that just "measure" things

If you're still using a basic ruler--the kind that's a stick with notches on it--allow us to introduce you to the future, where our rulers will be crazy interactive devices that measure the angles on hand-drawn triangles and allow us to create our own Plinko games on the backs of receipts.

Glassified, a project from the MIT Media Lab, is a ruler with a transparent screen on one end. A camera in the ruler can pick up on lines drawn on a sheet of paper, and the ruler can project light that interacts with those lines. That can can make for a fun game, or be used to track more complex measurements (the ruler can apparently measure the angles on a hand-drawn triangle).

Oh, and all the lines you draw will be so straight.

[Creative Applications Network]

    


The New Google/Motorola Moto X Smartphone Is A Quiet Delight

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Motorola Moto X

Dan Bracaglia

The difficulty and virtue of quiet is too often overlooked.

The new Moto X smartphone, Motorola's first start-to-finish project after its acquisition by Google last year, is here.

"Motorola's Moto X Must Be Game-Changing -- Or Else," writes Tim Stenovec, threateningly, at the Huffington Post. "With Moto X, Google Android is about to have its iPhone moment," writes Kevin Tofel at GigaOm. Christina Warren at Mashable asks if the Moto X can "revive Motorola's brand." Motorola is the fourth-biggest phone manufacturer in the U.S.; they've been around for 85 years and have twice in the last ten years completely changed the landscape of mobile phones (the RAZR, in 2004, and the original Droid, in 2009), which is more than most companies can say. They're owned by Google, a company with seemingly endless coffers. They're doing fine, guys.

This is all ridiculous. Not everything has to be revolutionary. Sometimes it's best to just step back, in both hardware and software, and do what feels right. It's an approach that's actually much harder than, say, Samsung's (which is a throw-everything-at-the-wall strategy); Motorola says they actually figured out the idea average volume of a phone's physical size. That takes time! But the end result is something that feels right not something that shouts at you.

I have a Moto X in front of me, and what's sort of refreshing about it is how it doesn't feel like a big deal at all. In a joint press conference, Google and Motorola presented the Moto X to small groups of journalists, 10 or 15 at a time, earlier this morning. They encouraged us to ask questions, even to interrogate them. It was friendly and intimate in a way that couldn't be more opposed to the bombastic Michael-Bay-goes-Broadway absurdity of the last big Samsung launch. And the phone is like that, too. It's just...nice.

The screen, at 4.7 inches, is big, but the body is not; the bezels are very small on the sides and the top and bottom borders are about half the height of the iPhone's. It is the first phone with a screen anywhere near that size that I can actually use one-handed, since the smaller overall size allows my little tiny ballerina hands to actually reach the top corners. It's thicker than an iPhone 5 or Galaxy S4, but it's rounded in the back and comfortable to hold. (The battery, Motorola tells us, had to use a unique "stepped" design to fit into that curve.)

"We're trying not to add complexity," says Rick Osterloh, Motorola's senior vice president of product management. "On an average Android phone, the homescreen is filled with stuff." They didn't entirely succeed; new features include "Active Display," which provides you with notifications when you flip the phone from face-down to face-up; "Quick Capture," which boots you into the camera app if you "give the phone a twist like a screwdriver"; and a camera that does not tap-to-focus like every other camera with a touchscreen ever made. If you're on AT&T, you can get the Moto X is a variety of colors, from tasteful to absurdly garish. Want a poop-brown back with neon pink volume buttons and an engraved message on the back that says "IM W/ GRUMPYCAT"? No problem.

Still, it's clear what Osterloh means. The camera app has two visible buttons: one to switch the camera from rear to front, and one to switch to video. It automatically begins taking video when you hit the video button. It automatically decides whether you should use HDR. It automatically decides where you want to focus.

The phone is at least as fast and responsive as the HTC One or Nexus 4, the two fastest Android phones I've tested. The screen, at 1280 x 720, is super sharp and clear. The battery is about as big as the HTC One's, but the phone itself is smaller. All is as it should be.

That "Active Display" mode automatically decides what your most important notification is, thanks to a hierarchy of notifications Google has compiled. There's a group of features called Motorola Assist that automatically adjust your settings when you're in a meeting (based on appointments in your Google calendar), when you're in a car (based on GPS location), or when you're sleeping. Google Now automatically does, well, everything. And now to use Google Now or Google's excellent voice command feature, you don't even have to unlock your phone. Just say "OK Google Now," a similar command to the "OK Glass" command that wakes up Google Glass. Then you can say "wake me up at 6a.m.," or "call Steve," or "did the Mets win last night?" (I saw the latter demonstrated; Google said "no, the Mets lost to the Marlins." It was pretty cool.) The whole point is to do less. Fewer button presses, fewer trips to the settings menu, fewer taps and swipes and clicks and holds and pinches.

The whole point of the Moto X isn't to be a "game-changer," it's to be a very good cellphone that you'd like to use. And it is! The hardware isn't as eye-catching as the HTC One, but it's more comfortable to use day-to-day. It's available on all major U.S. carriers at $199 on contract, starting in late August or early September, depending on your carrier (we weren't given specifics on this). It's probably the phone I'd recommend, because like the iPhone, the Moto X just feels comfortable. It's not doing anything crazy. It's just good. And that's a very mature place for Google to be.

    


Could There Be A Planet Hidden On The Opposite Side Of Our Sun?

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Transit Begins

SDO image in extreme ultraviolet.

NASA

We ask a scientist who has peered around it.

The sun might seem like a pretty huge galactic blind spot, but we've already managed to glimpse behind it, and there's nothing there in the way of another Earth, says NASA scientist Michael Kaiser, "unless it's awfully tiny."

Kaiser is the project scientist for NASA's Solar Terrestrial Relations Observatory (STEREO) mission, which in 2006 sent two golf-cart-size satellites into orbit around the sun to study the explosions on the solar surface that are a major factor in space weather. A few months after their launch, the two probes were angled such that they could see beyond the sun, but they found no planets lurking behind the big star.

Even if we couldn't see behind the sun, the gravitational pull of a roughly 100-mile-wide planet hiding there would noticeably affect the orbits of the other planets. And if astronomers had somehow missed that detail, Kaiser says, an unaccounted-for tug of gravity in the solar system would have disrupted the orbit of man-made satellites circling the Earth or interfered with intra-solar-system spacecraft. That hasn't happened, so unless beings on a hidden planet have invented both an invisibility cloak and a gravity-masking device, the other side of the sun is almost certainly just empty space.

This article originally appeared in the May 2009 issue of Popular Science magazine.

    


Aw: The World Through A Polar Bear's Eyes [Video]

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A camera-collar lets you vicariously swim and frolic and eat raw fish.

Meet Tasul, a polar bear at the Oregon Zoo taking part in a research project to help zoologists understand polar bear behavior (and maybe, by extension, strategies for preserving the species). Tasul wears an accelerometer, which reports on the bear's movements, along with a collar that has an Go-Pro attachable camera, giving researchers a first-person view of what Tasul sees. The researchers want to measure how Tasul reacts to environmental changes and, after this in-zoo trial run, will try out the project on wild bears, which we sincerely hope they release video of, too.

[Laughing Squid]

    


U.S. Forest Service Solves Mystery Of Exploding Baseball Bats

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Batter Up

Keith Allison via Wikimedia Commons

Major League Baseball has teamed up with the U.S. Forest Service to make baseball players' favorite bats safer to use.

Maple is the unofficial wood of baseball. Thanks to good old Barry Bonds, who used maple bats in his 2001 marathon home-run season, players increasingly favor the lighter wood, which according to one collector, just has "more pop" than other bat materials like ash.

Unfortunately, maple bats have a tendency to explode, sending sharp fragments of wood shooting in all directions, injuring fans and players alike.

More than half of all baseball bats sold to major-league teams last year were maple, and the MLB wants to make sure every batter stepping up to the plate isn't wielding a ticking wooden time bomb, so they've teamed up with U.S. Forest Service scientists to figure out how to make maple bats safer.

The scientists found that the more the cut of the wood strayed from the original grain, the more likely the bat was to shatter, The New York Timesreports. The baseball league altered regulations to require that the grain in the bat not deviate from the original grain of the wood by more than 3 percent, as well as adding minimum densities and weight-to-length ratios. Black ink was added to the wood to make the grain easier to follow.

It seems to be paying off. The rate of shattered bats has dropped for the past four years. Around 1,200 bats shattered in players' hands last year, compared to 2,500 in 2008. The average "multipiece failures per game," i.e. the number of bats that shatter into a million shrapnel pieces, has gone down from 1.0 in 2008 to 0.47 to 2013.

    



Evolution Punishes Selfish People, Game Theory Study Says

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Evolution punishes meanies

Dreamstime/ Joey Carmichael

How long can you get ahead by screwing other people over?

Contrary to our Darwinian inclinations, evolution may not be as dog-eat-dog of a world as we thought it was. The selfish can survive for a while, but according to new game theory research, long-term survival requires cooperation.

Game theorists were taken aback last year when a paper in the Proceeding of the National Academy of Sciences presented a new breakthrough strategy for the Prisoner's Dilemma, a classic game theory situation that presents two prisoners with the opportunity to either cooperate or betray each other in exchange for lesser sentences, widely studied as a model for economics, psychology and evolutionary biology.

Using a strategy called zero-determinant, or ZD (meaning that in the mathematical model, the value called the determinant is set to zero), the paper argued that selfish players could be guaranteed to beat cooperative players, enforcing "a unilateral claim to an unfair share of rewards." Since the Prisoner's Dilemma is used to explain biological phenomena, it raised the question: Does evolution favor jerks?

Selfishness isn't evolutionarily sustainable.Michigan State University microbiology and molecular genetics professor Christoph Adami and his research associate Arend Hintze immediately had doubts about whether ZD strategies could prove that evolution favors the selfish over the cooperative. In a paper published today in Nature Communications, they argue that according to their simulations, ZD strategies aren't evolutionarily stable, and that eventually, selfish players would have to become cooperative to survive.

"We found evolution will punish you if you're selfish and mean," Adami said in a press statement, vindicating every 8-year-old with a schoolyard squabble.

"For a short time and against a specific set of opponents, some selfish organisms may come out ahead," he explained. "But selfishness isn't evolutionarily sustainable."

That's because the selfish strategy only works when ZD players compete against players that aren't using the same strategy, and don't know that they're being manipulated. Against other ZD opponents, the strategy isn't viable, and so eventually, when the pool of players narrows to only ZD strategists, they need to adapt other strategies to win. According to Adami, "in the long run they would have to evolve away from being ZD and become more cooperative. So they wouldn't be ZD strategists anymore."

I can't do justice to the researchers' complicated math here, but their methods are detailed in full in Nature Communications. (Open access!)

    


Watch The Mars Rover Curiosity's First Year In Only 2 Minutes

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A busy, if slow-moving, year in the life of a robot we crashed onto an alien world.

The Mars rover Curiosity has spent the past year driving around the surface of of its new home, drilling and digging and collecting samples and every once in awhile drawing inappropriate body parts for fun.

It's not a speed demon, so we don't follow it minute-by-minute, but JPL just published a video shortening the past year in Curiosity's life down to 548 images, taken with the fish-eye lens mounted on the rover's front. The pics are great, a first-person look at Curiosity as it collects its first scoop of Martian soil and drills through cool extraterrestrial rocks. Hi Curiosity! Your year looks like it was fun.

[YouTube]

    


How Tom West Built A Pirate-Proof Yacht

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Pirate-Proof Yacht

Chris Cone

The 30-ton vessel, Faith, is armored to keep out unwanted guests.

Tom West has tackled some impressive builds over the years, including telescopes, a sawmill, and his house in Poland, Indiana. But West, a retired teacher, recently completed his swan song: a 30-ton, 56-foot-long sailboat named Faith. The one-mast vessel is longer than a double-decker bus, outfitted with wind turbines, and armored with a hull and cabin doors made from steel to thwart pirates on global voyages. "Everything you see, we did," West says, standing next to the craft in his yard. "This all started out in pieces-the whole damned boat."

West had little sailing experience, let alone boat-building know-how, before deciding to construct a huge ship in a landlocked farm town. He'd simply seen a lot of sailboats on a Hawaiian vacation and wanted to make one big enough to live on. West eventually settled on plans for a Bruce Roberts 532 vessel-a design sometimes used for charter boats-and refined them into his dream.

Most recreational cruisers are fiberglass boats measuring 26 to 40 feet long. Faith dwarfs these. It has two bathrooms, a full kitchen, lounging and dining areas, and room to sleep 12 people. A door with a ¼-inch-thick steel core protects the master cabin, which has the only access to the rudder controls, should pirates attempt a raid.

Building Faith took West, his wife, Martha, her brother Lloyd, and Tom's late brother, Frank, five years-three more than they'd anticipated. They started work in West's front-yard tennis court (another one of his custom creations). Using a plasma torch, the team welded steel beams together over concrete blocks to support the skeleton of the upside-down hull. Next they built two gantries to flip the hull upright. Anything that West could make, he did-including stainless-steel handrails, rope tie-offs, and the 65-foot-tall mast.

Getting Faith into water proved nearly as challenging as building the boat. The Ohio River, located about 150 miles away, was the nearest suitable connection to waterways leading to the Gulf of Mexico. It took the Wests a month to find a towing company able to execute a hair-raising one-day slog along highways and back roads. "The trailer was about an inch off the ground," West says. "It rubbed the ground every so often."

West says he named the craft Faith because he had to believe that one day he'd actually complete it (and it wouldn't sink). The moment of truth arrived in late April, at a Cincinnati marina. "There was a whole bunch of guys pushing on the boat," West says. "But the current was so fast that the ramp scratched the bottom." Then, after West started the engine, it blew a head gasket. Leaky pipes also plagued the maiden voyage, but the Wests successfully repaired their ship and headed downriver toward the ocean. They hope to pilot Faith to several continents, but their exact route is open to the winds of chance and curiosity. "This has added years to my life," West says. "I think that's the secret to life: get out and do something."

HOW IT WORKS

Crafting part of a 56-foot-long yacht is one thing. Learning to build Faith and install, maintain, and repair all of its parts is another. Here are just a few of the nautical systems West mastered during his five years of toil.

Power
A 100hp diesel motor and 500 gallons of diesel fuel give Faith 1,000 miles of range without wind.

Navigation (A)
A computer autopilot, radar system, sonar scanner, GPS unit, and a gyroscopic compass all work together to get Faith to its destination-with or without a captain.

Safety
To guard against pirates, West made the core of the master cabin's door from steel and incorporated a thick metal lock bar. The only access to the rudder controls is through the master cabin, so if there's a raid, the Wests can hunker down inside and disable the ship's steering. (A gun cabinet in the master cabin holds last-resort countermeasures.)

Electricity (B)
Two wind turbines on the back of the boat provide power for lights, electronics, and other systems. Faith also has a 10kW diesel generator, which fulfills most of its electrical needs.

Interior (C)
West harvested walnut trees from 50 acres of forest that he owns, cut the timber in his homemade sawmill, and used it to build the boat's cabinets, control panel, and tables.

Water
Faith's water-treatment system converts seven to nine gallons of seawater into tap water every hour, using carbon filters and a bacteria-killing ultraviolet light to get the job done.

WARNING: We review all our projects before publishing them, but ultimately your safety is your responsibility. Always wear protective gear, take proper safety precautions, and follow all laws and regulations.

This article originally appeared in the August 2013 issue of Popular Science. See more stories from the magazine here.

    


How To Make A DIY Anti-Surveillance Spray

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CCTV Blocking Spray Apparatus

Ai Weiwei

It's illegal, but that's kind of the point.

Incendiary Chinese artist Ai Weiwei, known for his highly political art, isn't exactly a fan of surveillance cameras. When Swiss art curator Hans-Ulrich Obrist asked Ai to contribute to a Do-It-Yourself compendium full of projects from artists, Ai designed an anti-surveillance camera apparatus, made from everyday objects.

Seizing on both its functionality and street culture significance, Ai's design is centered around a can of spray paint. The rest of the device works to get the spray paint into difficult-to-reach places, like the lofty perches where security cameras normally rest.

What You'll Need

Can of spray paint
Stick, ideally a collapsible tree pruner, but others are fine
Nylon rope
Bicycle break bar
Bottle cage from a bicycle
A wing corkscrew
Screws

Attach the bottle cage to the side of the stick near the top, to hold the spray paint can. Atop the stick sits the wing corkscrew, with one wing resting on the spray button on top of the can. Tie a string to the other corkscrew wing, and then stretch it down the length of the stick and attach it to the bicycle break bar. Squeeze the handle of the bicycle break bar, and it pulls the string, which pulls the corkscrew arm, which depresses the button on the spray can, which then sprays paint all over the offending camera.

(Full instructions are available at Brainpickings.)

This is illegal and unsubtle, which is largely the point of Ai's work. Distributing instructions for provocative DIY projects could even be considered the art itself.

The design comes from Hans-Ulrich Obrist's compendium "Do It," published in April.

This is almost as good as that time when Dutch artists put party hats on surveillance cameras for George Orwell's birthday.

    


X-Rays Of Spacesuits And Other Amazing Images From This Week

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Spacesuit X-Rays

What happens when an astronaut breaks a bone in space? Uh, almost certainly not this, actually… But! These x-rays of spacesuits dug up by The Atlantic, including this helmet from 1964, are great.

Mark Avino and Roland H. Cunningham, Smithsonian Institution via The Atlantic

Plus: a cake that looks like Jupiter, North Korea's next airport, and more


    


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