Every PIcture Tells A Story

By analyzing the mix of colors master artists since 1500 chose for painted landscapes, researchers can accurately reconstruct a record of the particulates in past atmospheres. The data may prove useful to refine contemporary climate change models.

"Sunset," c. 1875, by Winslow Homer/National Gallery of Art

Environmental data is turning up in unexpected places. In the April issue of Popular Science, Katie Peek reports on one such source: the journals of Henry David Thoreau. The 19th-century naturalist and writer wrote down such detailed, comprehensive observations on the flora and fauna around him that a Boston University lab was able to chart the impacts of climate change -- how much much earlier leaves appear, flowers bloom and birds migrate in the early 21st century compared to the Concord, Massachusetts of the mid-1800s -- by comparing Thoreau's notes to present-day conditions.

Visual art also carries a climate signal, it turns out. In a new study, scientists in Greece have verified that the relative intensities of red, blue, and green, or “red-to-green ratios,” in the paints mixed and used to depict sunsets by painters in the Northern Hemisphere, are excellent proxies for determining the levels of aerosols (fine dust particles or liquid droplets in the atmosphere) around the times that the paintings were created. 

As part of their analysis, published March 25 in the journal Atmospheric Chemistry and Physics, the scientists set up an experiment in which major Greek landscape artist Panayiotis Tetsis painted sunsets during and after the passage of airborne particulates from Saharan dust storms over the Greek isle of Hydra. Tetsis just painted what he saw, with no knowledge about the dust storms, and his red-to-green ratios matched data on aerosol optical depth gathered by sun photometers at the same times and places. Put another way: The more particulates in the atmosphere, the more they absorbed certain spectra of light, changing the color of the sunset to the artist's eye.

The team's latest work builds on a 2007 study in which they analyzed the red-to-green ratio of 554 painted sunsets, created by artists between 1500 to 2000 before, during, and after volcanic eruptions. In that research, the scientists found that the color ratio (“only the parts of the sky over the field of view of the artist near the horizon avoiding clouds were analysed”) correlated closely with how the volcanic ejecta would affect the appearance of light traveling through the atmosphere, and how long that effect would take to taper off.

The red-to-green ratios in these works also document increasing atmospheric pollution since the beginning of the Industrial Revolution, from around 1850 through the 20th century.

Along with telling us a lot about the past atmosphere, this climate data embedded in the West's fine art heritage may prove useful in refining the computer models that are used to study and predict the pace and effects of climate change.

[LiveScience]

iPhone 4's glass back

John Mahoney

Last June, Craig Federighi, Apple’s senior vice president of software, sneaked something big into his Worldwide Developers Conference keynote. On a slide listing features that would debut in iOS 7, an unfamiliar word appeared: iBeacons. An iBeacon is a small module that makes a spontaneous Bluetooth connection with a nearby smartphone to deliver packets of information. In December, stores, arenas, and other venues began to test the hardware, pushing coupons and other location-based information to customers. Like any technology, iBeacon is not inherently good or bad; it’s how we use it that will make the difference.

To understand iBeacon, it’s important to understand the underlying technology, Bluetooth Low Energy (BLE). Unlike previous Bluetooth devices, BLE ones don’t need to maintain a constant (and battery-draining) connection in order to share data. Instead they ping packets of information from their stationary locations. Only when another device comes into range will the two make a connection and share data. Manufacturers of health and fitness trackers have already put BLE to good use, creating devices that can gather data for days without a recharge. iBeacon makes it even easier to implement such exchanges, but not every company has our best interests as much at heart. 

iBeacon will allow companies to mine and use data about you in real time. With multiple iBeacons in place, stores can pinpoint your precise location, allowing them to monitor your browsing habits and promote products you’re likely to buy. We’re used to Amazon doing this, but soon your local MegaMart will be able to also. Say, for instance, you pick up tuna fish and then some celery. Pling! Your phone lights up: “Making tuna salad? Don’t forget the mayo! 20 percent off MegaMart brand.” While we’re curious about this new era of extreme couponing, it’s easy to see how stores might misuse it. 

That said, there are some helpful uses for location-specific information. Major League Baseball parks, including Citi Field in New York, will use iBeacons to guide you to your seats. (Citi will also use the system to sell you discounted hot dogs.) Radius Networks, a Washington, D.C., company, has released an iBeacon development kit, which individuals can use to build their own apps. Museums are talking about using the technology to push information about artwork to visitors as they move through galleries. And there’s potential for fun: Companies have used iBeacon to set up large digital scavenger hunts, and developers are cooking up games that could allow for spontaneous pickup matches that bridge the real and virtual worlds. 

The trouble is, iBeacon is an all-or-nothing scenario. The only surefire way to turn it off is to turn Bluetooth off altogether—also shutting down the connection to your headset or fitness tracker or smartwatch. But that’s not realistic; we’re attached to Bluetooth. Which means it’s up to individual developers and companies to make the right choices and treat us, our privacy, and our attention with a little respect.

This article originally appeared in the April 2014 issue of Popular Science. 

Terraced Rice Fields in the Yunnan Province, China

Jialiang Gao, www.peace-on-earth.org, CC BY-SA 2.5

Over the past few years, middle-class, urban Chinese folks have started buying organic. Constant news about new food-safety scandals has kindled their demand for what they see as cleaner, healthier food. Meanwhile, at least in one agricultural province, many farmers still aren't familiar with the concept of organic agriculture. But a local journalist has been teaching them, as well as local shoppers, with field trips, workshops, and a documentary supported by the Chinese government.

Li Yuan, a journalist for a newspaper in Kunming, China, produced a 25-minute documentary called "Ecological Growing" to teach shoppers and farmers about what organic produce is. Kunming could use it. It's in the Yunnan province in southwestern China, where the province's largest lake has received so much agricultural runoff that it's pea-green with algae. The government considers its water unfit for human contact.

Chinese farmers use about twice as much fertilizer to produce a ton of grain as U.S. farmers do, according to the Earth Policy Institute. That's in part because U.S. farmers are better aware of exactly how much fertilizer they should use. Li thinks some Chinese farmers use as much as five times as much fertilizer as their American counterparts would because they mistakenly believe they'll get higher yields that way.

Chinadialogue reports Li's "Ecological Growing" is simple enough for kids to understand. "We didn't want to overwhelm viewers with statistics and science. The film is a starting point for many people," Li told the environmental news website.

The idea is that Li's documentary will help catch Yunnanites up with the Beijing and Tianjin residents they feed. Yunnan produce is a "hot commodity" in those cities, Chinadialogue reports. In spite of its environmental troubles, the province is pastoral, pretty, and low in density compared to other areas in China. City-dwellers see it as a source of safe, clean produce. 

[chinadialogue]

Machine Learning

Computer visualizations of tree swallow migration and roosting during fall migration, based on weather radar data, developed by scientists at Cornell, Oregon State and Tulane universities.

BirdCast

Via Alexis Madrigal, we've learned of BirdCast: a project from Cornell University's Lab of Ornithology and other institutions that hopes to create sophisticated predictions of bird migrations in real time. BirdCast aims to bring current advances and innovations in computing power and data analysis to birdwatching on the continental scale, by creating computer models that will "reconstruct and predict the behavior of ~400 species of migrating birds across North America;" creating a standardized and open-source methodology for managing bird-related data (observations, weather data, radar readings, satellite imagery, human population, and more); and translating all this information into web-based visuals that will appeal to and inform the general public about conservation, ecology, and computer science.

Artist's Rendering of (10199) Chariklo and Its Rings

Lucie Maquet

Meet (10199) Chariklo. It's an asteroid-like object that's a little more than 90 miles in diameter. It orbits the sun between Jupiter and Neptune. And like its giant gas neighbors, it has rings. Asteroids have rings, too! (Go and brush your shoulders off.)

This is the first time any object besides a Solar System gas giant—Jupiter, Saturn, Uranus, Neptune—has been found to have rings. Chariklo is technically a centaur, one of many centaurs that orbit between Jupiter and Neptune and have both asteroid-like and comet-like properties, which makes them a bit of a mystery. Asteroids and comets are distinguished by where they were formed and what they are made of; Chariklo, the largest of the centaurs, happens to be is more asteroid-like. 

Astronomers now think Chariklo has two flat, dense, thin rings, about 4.3 miles (7 kilometers) and 2 miles in width, with a 5.5-mile gap between them. The rings likely have ice in them.

An international team of astronomers determined that Chariklo has rings after observing it cross in front of a star on June 3, 2013. Such events, called occultations, are good opportunities for astronomers to learn about celestial bodies because they can see how the object they're studying blocks light from the star behind it.

On June 3, the Chariklo-observing team gathered data from telescopes in Brazil, Argentina, Uruguay and Chile. The astronomers were seeking to determine Chariklo's shape and to measure its size more exactly. They ended up learning much more.

What It Would Look Like To Stand On (10199) Chariklo

ESO/L. Calçada/Nick Risinger

Chariklo blocked light from the star not only during the expected time but also before and after, suggesting there was something surrounding the centaur. Data from the South American telescopes let astronomers determine the shapes of these rings.

The ring hypothesis helps explain a series of unusual observations about Chariklo. Between 1997 and 2008, the centaur appeared to get dimmer. It also gradually stopped reflecting wavelengths of light that astronomers associate with ice. After 2008, it brightened again and the ice seemed to reappear. The team now thinks that during that dimmed decade, Chariklo's ice-containing rings moved so their narrow edges faced Earth. They stopped reflecting light as brightly, making the otherwise dark-colored centaur seem duller. Meanwhile, the ice they contained seemed to "disappear" from the surface of the centaur.

Could other asteroid-like objects have rings, too? In a paper they published today in the journal Nature, the Chariklo-observing astronomers wrote that scientists have observed many occultations involving asteroids in the main asteroid belt between Mars and Jupiter. None found rings. In 1993 and 1994, a series of occultations involving a centaur called Chiron revealed it has material coming off of its surface in a jet-like stream. But astronomers are unsure whether it's just a coincidence that both centaurs have material surrounding them, or whether Chiron and Chariklo might share some physical process that made one's jet and the other's rings.

Meanwhile, the research's lead author thinks there could be more around Chariklo. "So, as well as the rings, it's likely that Chariklo has at least one small moon still waiting to be discovered," Felipe Braga-Ribas of the Observatório Nacional in Rio de Janeiro told the European Southern Observatory.

Pottery

Wikimedia Commons, Courtesy ZSM

For more than 50 years, engineers have built the rods that hold nuclear fuel the same way, out of zirconium-based metal alloys. They maintain structural integrity at high temperatures and allow uranium neutrons to escape in order to produce nuclear reactions. But, as Fukushima demonstrated, they have a very serious drawback: At about 2,000°F, the stuff quickly reacts with steam, releasing heat and hydrogen gas that can easily ignite—and then explode.

1) Silicon carbide (SiC) ceramic rods can do everything that zirconium-based ones do. 

2) But they are far less reactive with hot water.

3) And they’re still strong at 2,900°F and higher. 

4) Several companies have been working on SiC rods, including Maryland-based Ceramic Tubular Products, which tested them under accident conditions last year.

This article originally appeared in the April 2014 issue of Popular Science.

The 3-D Printed Skull

From a video by UMC Utrecht

A woman with a rare bone disorder has had much of the top of her skull replaced with a 3-D printed plastic piece, Wired U.K. reports. Three months later, she's symptom-free and back to work.

The woman's condition made her skull increase in thickness, giving her severe headaches and affecting her eyesight. The surgery, performed at the University Medical Center Utrecht in the Netherlands, gave the woman a replacement that closely matched the original shape of her skull. "It is almost impossible to see that she's ever had surgery," her lead surgeon, Bon Verweij, said in a statement from the university.

Verweij's team has used 3-D printing to replace some portions of skulls before, but never to this extent, Wired U.K. reports.

You might see more such stories in the near future. While researchers are still working on 3-D printing soft tissues that are safe for transplants, 3-D-printed bony parts have already shown up in specific surgeries. As in the Utrecht case, doctors often emphasize how personalized such replacements can be.

Three years ago, a British man who had much of his pelvis removed got a replacement 3-D printed in titanium, the Ottawa Citizen reports. Printed titanium implants are made by spitting out titanium powder that's then fused by a laser beam. The man's doctor thought a printed replacement would fit better than a standard, handmade one. The man now walks with a cane, the Citizen reports.

In June 2011, a patient in Belgium received a 3-D printed titanium jawbone replacement. This was the first total lower jawbone replacement made to match a specific patient, the BBC reports.

And just last year, Livescience reported a Connecticut-based company received U.S. Food and Drug Administration approval to market a plastic replacement for 75 percent of the skull.

[Wired U.K.]

With An Audience

A local health care provider gives a child polio vaccine drops. Northern India, 2000.

CDC/ Chris Zahniser, B.S.N., R.N., M.P.H.

The World Health Organization is officially declaring today that its South-East Asia Region, comprising 11 countries, is polio-free. That means poliovirus—which can cripple or kill infected babies—is no longer endemic there. However, any unvaccinated South-East Asia Region residents may still get sick from polio transferred from other countries.

Among other things, the World Health Organization is having high tea to celebrate. You can see the schedule for the day at the regional office's website. You can also watch a livestream of the official declaration starting at 9:00 am Eastern, or 2:00 pm in India, where the celebration will be held.

Just a few years ago, clearing polio from India was considered a nearly impossible hurdle, as Popular Sciencereported in January. India was the last country in the South-East Asia Region to eradicate polio.

Now, the challenges lie in the Middle East. In Iraq and Syria, violence and the dislocation of refugees make it hard for vaccination campaigns to stay strong and reach all the kids they need to. Earlier this week, international officials confirmed Iraq has one case of polio, its first in 14 years, IRIN reports. Syria is also sustaining a polio outbreak, as the war there has stalled vaccination efforts. Before the war, 99 percent of Syrian kids were vaccinated against polio, NBC News reports. In 2012, only 52 percent of eligible children got the vaccine. Officials are especially worried that Syrian refugees will bring more polio into Iraq. 

Smart goat

A goat pulling a lever (A), lifting a lever (B), and enjoying the "fruit" of its labor (C).

Briefer et al. / Frontiers in Zoology

New research found that most goats tested could quickly figure out how to solve a "mechanical puzzle" that yielded a delicious piece of fruit. In this case they had to pull on and then lift up a lever, a "highly novel cognitive task." Completing this two-step process caused a box to open, within which was a piece of fruit. Of the 12 goats tested, nine of them got it within fewer than a dozen trials on average. Two of them were disqualified for trying to pry open the fruit-box with their horns, which actually might have been a smart idea (and it's not like the goats knew they'd be DQ'ed), and one was dismissed as hopeless upon not showing signs of learning the task after 22 trials.  

The scientists re-tested the goats 10 months later, and this time they solved the puzzle much more quickly, within two minutes. "The speed at which the goats completed the task at 10 months compared to how long it took them to learn indicates excellent long-term memory," co-author Dr Elodie Briefer, at ETH Zurich, said in a statement. 

The study, published this week in Frontiers in Zoology, shows that goats can learn rather quickly, and can also store these lessons in long-term memory. Researchers had suspected that goats are intelligent, based on their ability to colonize new and harsh environments, to find and remember the location of hard-to-reach foods (for example Moroccan goats are known to climb trees to reach sprigs), and their relatively long lifespans, during which time they can build up a repertoire of memories and skills, as reported by Smithsonian.

Mars colony

Mars One

Creating a permanent human settlement on Mars by 2025 will require serious training. To prepare its future astronauts for the task, the Netherlands-based private spaceflight project Mars One announced today its plans to construct Earth-based outposts that replicate the cramped, isolated, crazy-making conditions of a Red Planet colony.

In an email statement this morning, Mars One also named Kristian von Bengston—co-founder of Copenhagen Suborbitals, a private effort to build and launch a crewed suborbital rocket—as leader of the new effort to establish multiple training outposts at yet-to-be-determined locations. For now Von Bengston is seeking out construction companies and courting financial sponsors. The first simulated colonies won't contain actual life-support systems, at least to begin with, but they will be retrofitted with the technology later on, according to the statement.

More than 200,000 people applied for the one-way mission. Late last year, Mars One narrowed the selection pool to 1,058. Their ultimate goal: select 24 to 40 candidates who will travel to Mars in groups of four (two men and two women, ideally from four different continents, says CEO Bas Lansdorp). Mars One wants to send the first group in 2025, with the subsequent crews launching one at a time, every two years thereafter. The organization intends to televise the final rounds of the search. 

Spaceflight contractors Lockheed Martin and Surrey Satellite Technology Ltd. are already working with Mars One to develop a robotic lander and a data-link satellite for an unmanned, exploratory mission to Mars in 2018. Should this initial mission get off the ground, it would test several technologies required to support human life on another world.

Last August, Popular Science spoke with one of the applicants, video game designer Katrina Wolfe, who has since made it to round two of the selection process. Read our interview with Wolfe here.  

Cartoon of a Budding Yeast

Maki Naro

Humans have been engineering yeast "for thousands of years," says Jef Boeke, a researcher with New York University's medical center who is one of the world's top yeast biology experts. At first, I thought he was exaggerating. Yeast has been ubiquitous in science labs for decades now, studied in every possible way, like a microscopic lab rat, and I thought Boeke was referring to that.

But he was referring to a more basic sort of manipulation: humans have been growing yeast for their own ends since they figured out how to brew beer and bake bread. "So we have this ancient industrial relationship with this organism," he says.

Now he has taken the relationship to a whole new level. Boeke recently led a team of biologists in designing and building, from scratch, one chromosome of brewer's yeast's DNA. (A chromosome is an individually-packaged portion of a creature's DNA, like the X or Y chromosomes in humans.) The man-made yeast chromosome represents about three percent of all of the DNA that makes a yeast. This is the first time scientists have been able to assemble a chromosome from a creature as complicated as a yeast.

"The synthesis and design of the first eukaryotic chromosome is obviously an exciting milestone," says Farren Isaacs, a cell biologist at Yale University who was not involved in Boeke's team. "Eukaryotic" refers to the grouping of life that yeast belong to.

You might remember that in 2010, the J. Craig Venter Institute built all of the DNA for a bacterium from scratch. Yeasts are a step up from bacteria. They're single-celled critters like bacteria, but, among other things they do differently, they manage their DNA in a more complicated way. That lets them do more with same building blocks.

Yeast and bacteria are different enough that scientists give them two different designations. Bacteria are called prokaryotic. Prokaryotes are among the world's simplest cells, akin to the very first living things to squiggle on the face of the Earth. Yeasts, on the other hand, are eukaryotic, a group of living things that encompasses everything from them to plants to people.

Microscope Photo of Yeast

The yeast are dyed blue.

CDC

That said, building the DNA of a eukaryote isn't that different from building the DNA of a prokaryote. "When it comes down to the actual synthesis," Boeke says, "DNA is DNA. If you can synthesize prokaryotic DNA, you can basically synthesize eukaryotic DNA."

Four years after the creation of a bacterium genome, the advance this time is that the artificial chromosome Boeke made is meticulously engineered. Boeke's team members didn't just copy Nature. They improved on it. They snipped away some bits of DNA. They added others. They even added some stretches of DNA that give the chromosome a latent superpower that doesn't come into play unless it's triggered. If scientists add a certain chemical to the yeast, specific parts of the artificial chromosome are able to rearrange themselves in new, random combinations. "It's almost akin to being able to trigger evolution," Isaacs says. 

To check that the synthetic chromosome is a workable blueprint for yeasty life, Boeke and his colleagues put it back into yeast from which they had removed the natural version of their artificial chromosome. The natural-artificial hybrid yeast grew and reproduced like its wild cousins. "It looks like it, it behaves like it, it smells like it," Boeke says. "Basically, you wouldn't know the difference unless you take the next step and introduce what we call the genome scrambling system into it."

It's not immediately clear where scientists outside of the team will take this next. Boeke's lab has its own plans, of course. It's long worked on building all of the DNA for a yeast, making steady progress. In 2011, not long after the announcement of the world's first artificial bacterium chromosome, Boeke's lab announced it had made one arm of a yeast chromosome. It hopes to manufacture all 16 of yeast's chromosomes over the next few years.

Beyond that, Boeke hopes the DNA-scrambling technology the team created will become a new bioengineering tool for researchers and biotech companies. Scientists and companies have tweaked yeast DNA to make the creatures produce medicine, biofuels and other chemicals people want. Maybe DNA scrambling will help bioengineers find and create yeast that are a little more efficient, or a little hardier, Boeke says.

Isaacs thinks that in the future, bioengineers will combine editing existing DNA—the type of bioengineering that's most common now—writing new DNA, which is what Boeke did.

Sounds like yeast will be a part of human biotech for many years yet.

Boeke and his colleagues published their work on the yeast chromosome in the journal Science.

Corrected March 27: This post originally said Jef Boeke is a researcher at Johns Hopkins University. Boeke has moved from Johns Hopkins and is now with New York University's Langone Medical Center. 

Eielson Air Force Base, Alaska

Aurora Borealis over Alaskan Air Force Base

Joshua Strang for USAF, via Wikimedia Commons

Here's a roundup of the week's top drone news, designed to capture the military, commercial, non-profit, and recreational applications of unmanned aircraft.

Alaska Bans Drone-Assisted Hunting

Last week, the Alaska Board of Game passed a measure prohibiting hunters from using drones to find game. The underlying principle behind this is one of fairness—drone-aided hunters would have an advantage over hunters without flying robots. Yet there's a bias in this prohibition. As it stands, hunters are allowed to use manned aircraft to look for game, and then hunt that game the next day. Because hunting with drones is now always prohibited, there's no way for a hunter to use a drone to scout for moose one day and then track them without the drone the next, unlike a Cessna-flying rival.

The best part of the proposed regulation is the list of items, in addition to drones, hunters are prohibited from using: "poison, bombs, radio communication or exploding salt licks, among other things."

Alaskan Ice Caves

"Bigger than Life" is a film project showing the inside of ice caves in Alaska. Neat! The excellent cave photography was captured by drones  (DJI Phantoms, specifically), and in the making-of video there's footage of the drone in action.

Watch film of a drone filming below:

Above St. Petersburg

While Russia's actions on the international stage aren't terribly pretty, St. Petersburg remains a gorgeous city. Photographer Amos Chapple used a drone to capture the city from above, using altitude to show shadows running long and catching the faces of angels in snow.

Australian Accident, Almost

Last Saturday, in the skies above Newcastle, New South Wales, a hospital helicopter saw lights. The pilots assumed the lights were from a distant aircraft, but they were actually from a much closer drone. Both helicopter and drone were flying at around 1,000 feet, which is normal for helicopters but rare and, in Australia, prohibited for drones. In the United States, the FAA is currently trying to figure out how low to the ground aviation regulations extend, and it's clear from incidents like these that drones can indeed pose a risk to manned aircraft like planes and especially helicopters.

Altius Drone Unveiled

Last night, Russia's government-owned Channel One Russia revealed a new drone during a segment where Russian Prime Minister Medvedev toured an aircraft factory. The drone is large and two engined, which is unlike any in the American drone inventory.

Altius Drone

Channel One Russia

Did I miss any drone news? Email me at kelsey.d.atherton@gmail.com

Noah's Ark Sculpture in the Netherlands

Photo by Centurion on Wikimedia Commons, CC BY-SA 3.0

This weekend Russell Crowe, as the lead role in Darren Aronofsky​'s $125 million production of Noah, will pile countless animals into a wooden ark in anticipation of a watery apocalypse.

Here at Popular Science, we know that when an animal population gets cut down dramatically, there's a danger they'll suffer from inbreeding. After all, early on in repopulating the world, they may only have relatives to choose from as mates—and mating with relatives increases the risk that offspring will get two copies of dangerously mutated genes, e.g. one from mom, one from dad, and zero alternative copies for a healthy mix.

Animal species differ wildly in their genetic diversity. Fruit flies, for example, have about ten times as much genetic variation as humans do. Individual nematode species are 100 times more varied. So we wondered if that meant nematodes, like this guy, would stay the healthiest after a catastrophic event like, oh, say, the biblical flood.

Brian Charlesworth, an evolutionary biologist at the University of Edinburgh in the U.K. and the editor-in-chief of the evolutionary biology journal Biology Letters, helped us explore which animals would be best protected from inbreeding after an extreme population drop. Charlesworth told us that the most important thing to look for in repopulation success is not genes—but how fast an animal species reproduces.

Biologists know this from studying how animals fare after arriving on remote islands. Their success is determined by their ability to quickly multiply, Charlesworth says, "before they go extinct because of small population size or the failure of individuals to reproduce."

In fact, biologists think that as long as a species reproduces quickly enough, it won't lose too much of its natural diversity from a Noah's Ark-like event. "If the population expands immediately, it doesn't lose that much diversity from a bottleneck of two," Charlesworth says. "It will maintain something like one quarter of variability that was there before." He cited calculations published in the 1965 book The Genetics of Colonizing Species.

On the other hand, species whose population numbers would stay low for a long time are exposed to the risks of inbreeding. That's good news for flies and mice; not so great news for elephants.

Making many babies matters more than inherent genetic variation because even animals with low genetic diversity generally have enough variability to weather a new environment. Charlesworth explained that humans aren't so different from one another, at least genetically. Yet, within the last 10,000 years, different populations evolved the ability to resist malaria infections and to digest dairy products, depending on their needs.

"I don't think there's really compelling evidence to say, 'This organism has low genetic diversity and therefore it's not going to do very well,'" he says. "If so, humans have a bleak future."

Biologists' ability to put a number on species' diversity comes from genetic sequencing technologies that have appeared only in the past decade or so. One cool corollary of that: By looking at how individuals within a species genetically vary from one another, biologists can find evidence of sudden reductions in population sizes in species' past.

Thus, an event like the Biblical flood should leave its mark in most animals' DNA—but Charlesworth says "there's absolutely no evidence of any kind of bottleneck in the very recent past in the vast majority of species."

In Aesop's fable of The Crow and The Pitcher, the thirsty feathered protagonist comes across a pitcher partially filled with water, but cannot reach the delicious liquid with its beak--it's just out of reach. Being very clever, the crow drops stones into the pitcher until the water level rises and the crow can drink. 

But this is no mere fable. Recent studies have shown that New Caledonian crows--native to islands in the southwest Pacific--actually are capable of similarly ingenious feats, and can drop stones into tubes of water to raise the water level and retrieve floating pieces of food.

But do they understand exactly what's going on? In other words, do they grasp that the stones are capable of displacing water? In a study published this week in PLOS ONE, researchers designed a series of tests to find out, and they concluded that the crows "possess a sophisticated, but incomplete, understanding of the causal properties of displacement, rivaling that of 5–7-year-old children."

To reach this conclusion, scientists first caught six wild New Caledonian crows (Corvus moneduloides), and trained them to drop rocks into tubes without water to receive a treat. They then presented the birds with a variety of tubes, some filled with water and others with sand, with treats just out of reach. They also gave them a variety of objects to drop. Here's what they discovered: 

"The results show the crows possess a sophisticated understanding of the causal properties of volume displacement, similar to that of five- to seven-year-old children," study author Sarah Jelbert, from the University of Auckland, told ABC. 

The study further shows what was already known to an extent: that New Caledonian crows are remarkably intelligent. They are, for example, the only non-human animals that fashion their own tools, making hooks out of twigs, something not even primates like chimpanzees can do. 

Cells At 40x Magnification

Source: Louisa Windus, at Griffith University in Queensland, Australia, studies how cancer cells grow and spread.

Courtesy Louisa Windus

Cells live in a three-dimensional world, but until recently, scientists using fluorescence microscopes could see them well in only two dimensions. With advances in confocal microscopes, which use pinhole apertures to focus light on several planes, scientists can now view samples with depth, like these human prostate-cancer clusters.

This article originally appeared in the April 2014 issue of Popular Science.

The astronomical instrument BICEP2 was deployed at the South Pole in 2009 to look for evidence that would support the theory of inflation, which tries to explain how the universe looked a trillionth of a second after the Big Bang.

Why the South Pole? Because there the sky is the cleanest and the clearest – no man-made light or radio pollution and minimal water vapour in the atmosphere. These would absorb the signals that the instrument was developed to record. The regions of sky targeted for observation are known to be particularly clear of contaminating microwave emissions from the galaxy and are always above the horizon.

On March 17, headlines around the world hailed the BICEP2 as having made biggest scientific discovery of the year. So what was it like to work on this historic project?

Where penguins wouldn’t dare

BICEP2 was designed and built at the California Institute of Technology (Caltech), Pasadena. The team was assembled by the late Andrew Lange and then led by Kovac (now at Harvard), Jamie Bock at Caltech, Chao-Lin Kuo at Stanford University and Clem Pryke at the University of Minnesota. I joined the BICEP2 team in 2007, on loan from Cardiff University, as their instrument development scientist. In the autumn of 2009, together with three fellow BICEP2 adventurers (others would follow as the season progressed), we headed out from sunny southern California to the Amundsen-Scott South Pole Station.

Aligning the receiver and camera insert before the telescope tube is lowered onto it. Rashmi Sudiwala

We first flew to New Zealand, to be kitted out with extreme weather clothing. Then onwards for a stopover at McMurdo Station on Ross Island before heading out to the South Pole. The −50 centigrade air stung my eyes and lungs as I got off the plane. The short walk from apron to station left us gasping for breath: the altitude is 10,000 feet above sea level. The BICEP2 telescope location was only a quarter-mile from the station but the hike felt a lot further the first few times.

It was my second time at the South Pole. I had briefly visited the previous season to help decommission the original BICEP. That experience, coupled with my intimate knowledge of BICEP2, meant I was team leader for the first week. Not that the team needed leading – our collective desire to make the project work was by far the greatest motivator.

For the love of science

There were many tasks to be performed in readying the instrument for service. We didn’t have the option of simply fielding a ready-made, pre-calibrated machine. The telescope shell, camera tube, optics, cooling system, cables (so many cables), and the all-important detectors had to be prepared, assembled and calibrated on site whilst control software had to be written or tweaked. Plus, the detector assembly we actually wanted to deploy was still under test in Pasadena in our test system.

Our first tasks were organising the observatory and checking the telescope mount for wear and tear – polar winters are brutal. With brooms, vacuum cleaners and snow shovels, it was all hands on deck. Shovelling snow certainly gets the heart pounding – so much for taking it easy as we acclimatised to the high altitude!

Over the following days and weeks, crates containing what would become the BICEP2 instrument arrived, along with more team members. The workload was huge and the schedule relentless – the clock was ticking.

We played to each other’s strengths. Team specialists and station staff chipped in doing whatever, wherever, whenever. Trained as a physicist and employed as an instrument scientist and systems engineer, my skills were more general. I had particular expertise in cryogenics (handling really cold things), electronics and control systems. At the South Pole, it seemed as if I only made cables, routed cables, and tested cables. How many PhDs does it take to thread a cable? Five, and then some.

The team at Caltech. Rashmi Sudiwala

On December 13, 2009, the BICEP2 instrument was ready for action. Procedures honed over a period of two years in Pasadena had been implemented in just three weeks here. By December 16 the system was fully cold, meaning that experiments could begin. Following initial checks, we were able to take our first measurements: first light.

There was never great doubt that the instrument would work – we had all done our homework. But for me there had been a concern. The detectors in BICEP2 operate at a temperature close to the coldest temperature that we can ever reach. To achieve this, we use a fridge that is colder than liquid helium. Back in Pasadena, we had experienced huge problems with running this fridge, but after many long nights I had stumbled upon a solution which seemed promising. With some tweaking at the South Pole, the fridge held its temperature for 85 hours.

Humour at the pole

It helps to have a sense of humour, although sometimes the humour was against us. Like when a colleague’s flight was forced to circle a few hours above the station only to be turned back to McMurdo (our breakfast meeting notes record, “… Angiola still circling overhead”). Medical health is of paramount concern and this was the year the swine flu virus was all the rage. I dutifully took my jabs, only to go down with the most horrendous aches, pains and fever imaginable. After four or five days, groggy and worse for wear, I managed to drag myself to the galley for some food – to others' amusement.

It was not all work. The station has recreational facilities, including a full-size sports gymnasium and music room. There was a wealth of talent amongst the station staff and scientists from other experiments. You might find yourself attending impromptu classes in everything from photography to flamenco dancing. There are other experiments at the South Pole: IceCube, the South Pole Telescope, meteorology and a self-sufficiency experiment for long-duration space missions. Everyone liked to show and tell, with open-days and seminars. My highlight was one given by a film crew shooting the BBC’s Frozen Planet documentary, and I was thrilled to bits to have met Sir David Attenborough.

By mid-January most systems had come together. There was still much to do in terms of testing and calibration, but on January 18 it was time for me to leave. After lunch, with a stiff upper lip, it was a manly handshake for the men, a warm hug for the ladies, and with that my Polar adventure came to an end.

Fruits of our labour

It was known from the outset that my role was to get the instrument built, tested and deployed. It was thrilling to see the first light data in December 2009. But I’m no theorist or data analyst. I remained on the BICEP2 mailing list, and from a distance, kept in touch with the program as data accumulated. Data analysis started from the outset and there was a long wait for the statistical noise to average down. The mood of the team, rising and falling with every new problem encountered and solved, could be judged from the email traffic.

Rashmi Sudiwala

The BICEP2 data analysis team is a small, tight-lipped group. I knew perhaps a year ago that there was talk of possible primordial gravitational wave detection by BICEP2 but I was taken completely by surprise of news of the imminent media release from the Harvard press office.

To think that this machine, of modest size, located in the harshest of environments, was so sensitive and characterised to such exquisite detail that from it we could extract the faintest of signals from the farthest reaches of the Universe and the tiniest fractions of a second after the Big Bang is amazing. That this signal itself represents compelling evidence for inflation, arguably one of craziest scientific theories describing the birth of our universe, is staggering. And there will no doubt be more revelations to come.

My thanks to the late Andrew Lange, John Kovac and the BICEP2 team for allowing me to work on the program; to the NFS, USAP, JPL, Caltech, the Moore Foundation and the Keck Foundation for funding the program; and to Peter Ade and Cardiff University for granting me leave.

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

Saves the Day

Twitter

“Twitter activity provides a more fine-grained representation of a community’s health than demographics alone,” said Aron Culotta, a researcher at the Illinois Institute of Technology, in a statement. “The reason for this appears to come from the insights Twitter provides into personality, attitudes, and behavior, which in turn correlate with health outcomes.”

Culotta collected 4.3 million tweets from people in the 100 largest counties in the U.S. He then performed a linguistic analysis, and found a few interesting and occasionally counterintuitive things:

Researchers can also look for more obvious signs of illness, like "staying home with a sore throat." 

This is not the only instance of researchers using Twitter to examine public health. A study at the University of California, San Diego, for example, is using the platform to monitor depression and mental illness. Twitter has also been used to track HIV outbreaks and reports of food poisoning. 

Atlantic Spotted Dolphins

So long, and thanks for all the fish.

Wikimedia Commons

"I was like whoa! We have a match. I was stunned," researcher Denise Herzing told New Scientist. At the time, in August of last year, she was wearing a prototype dolphin translator called Cetacean Hearing and Telemetry (CHAT). The device is encased in a waterproof shell and contains hydrophones that detect dolphin whistles, which can be up to 10 times higher than the highest pitch a human can make out. The whistle was one that she and others had taught the dolphins and trained them to associate with seaweed. 

Herzing is quick to point out that the observation has limitations, since it hasn't been repeated. But is a significant moment, other researchers said, and along with improvements in information-processing abilities signals of a new era for understanding--and even possibly participating in--animal communication. 

Herzing and Georgia Tech researcher Thad Starner are using pattern-discovery algorithms that are designed to analyze dolphin whistles and extract meaningful features that a person might not catch or know to look for. They are listening for invented whistles they taught the animals, and are trying to understand the dolphin's natural language as well. 

[New Scientist]

Daniel Hashimoto appears to be a pretty cool dad. The After Effects artist for DreamWorks Studios does his magic on videos of his 3-year-old son, transforming the little guy into a superhero capable of slicing through store shelves with a light-saber and shooting things with a Lego gun. Also, did you ever play the lava game, where you pretend that the ground is molten rock? I sure did. But I don't have a dad that then made it appear as if the ground really were lava in a video. You can check out all of the videos at Hashimoto's YouTube page, Action Movie Kid, and more are below. Happy Friday! 

[via The Independent]