New Lightning Detector in Space Could Revolutionize Meteorology

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 Close to midnight on January 3, 2017, Samantha Edgington and a team of scientists gathered to remotely open the door of an instrument on the GOES-16 weather satellite they had spent a decade creating. The tool, a geostationary lightning mapper (GLM) meant to track lightning on Earth from space, was 35,000 kilometers in the sky above Earth onboard a newly-launched satellite.
 

 “To be honest, I didn’t think we were going to see anything very much when we first opened the door,” said Edgington, a system architect at Lockheed Martin, “No one could sit still as we waited for the data to show us how the instrument was working.”
 

 Once the door opened, Edgington’s expectations were wildly exceeded and the team erupted in cheer.
 
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<figcaption>The GOES-16 weather satellite
 
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 “We open the door, we get not only [lightning], but we also get background images every two-and-a-half minutes,” Edgington said, “The first that came in, it was the sunrise over the Atlantic in Brazil, and it was just the most beautiful thing I’d ever seen.”
 

 “We had all invested years of our careers into this moment,” Edgington said, “And it was surprisingly emotional to see the results and share the moment with colleagues we had worked with—for ten years in my case.”
 

 The results Edgington mentioned will be used to help forecasters broadcast earlier warnings about severe weather.
 

 GOES-16, part of a series of GOES weather satellites, was jointly developed by the National Aeronautics and Space Administration and the National Oceanic and Atmospheric Administration (NOAA). Lockheed Martin was contracted to design and build the most recent satellite series, including both GOES-16 and the GLM.
 

 Earle Williams, principal research engineer at MIT, explained what the GOES-16 GLM adds to meteorologists’ toolkits.
 

 While previous satellites could only detect lightning from low Earth orbit for only short bursts of time, he said, GOES-16’s GLM can “map lightning over the entire Western Hemisphere.”
 

 So far, the GLM onboard GOES-16 has sent back to Earth an unprecedented amount of lightning data that will help meteorologists and forecasters gain a better understanding of severe weather phenomena.
 

 “GLM has collected more data on lightning from space so far than all the rest of the lightning mapping missions combined in just the time it’s been in orbit,” Edgington said.
 

 The satellite and its instrument are currently in a test orbit, where scientists have been working to improve the GLM and the data it can provide.
 

 Scott Rudlosky, a physical scientist at NOAA who works on GOES-16 GLM, has been closely monitoring the instrument. He said its performance will continue to improve as scientists optimize the its algorithms. The biggest changes, he said, were incorporated in October and November of 2017, though already, GLM collected valuable data during the recent hurricane season.
 

 “Having the GOES-16 active during the 2017 hurricane season likely doubled the amount of information that we have to help link total lightning activity to hurricane intensity changes,” Rudlosky said.
 

 The instrument tracked increased lightning in the eyewalls of Irma and Maria, and lots of lightning in the outer bands of Harvey, Edgington said.
 

 Lightning sustains an electrical balance between the sky and Earth, and during storms, the frequency of lightning correlates with how quickly a storm intensifies. “[Meteorologists] use lightning data to get a sense of a storm’s intensity, for determining where a forest fire might have been initiated, etc.” said Scott Steiger, an associate professor of meteorology at Oswego State University of New York.
 

 In the planning and creation of the GLM, Edgington said, “the main push was more accurate tornado predictions, but we think it’s going to be able to help with other things as well, like flash flooding or hail.”
 

 Rudlosky hopes the data from the GLM will be available soon once the instrument is in its final position: “With any luck, these data should be available to all [National Weather Service] forecasters by the end of January 2018.”
 
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 Image credit: NASA

Bacterial Tug of War May Cause Acne

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 The causes of acne could be more than skin deep—maybe gut deep, according a new investigative study performed in China.
 

 The recent study detailed in the
 
 Journal of Investigative Dermatology
 
 reports that patients afflicted with acne have distinct differences in the ratios of their gut microbiome compared to patients without acne. These differences may be reflected in the skin microbiome.
 
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<figcaption>Acne may be the result of a link between our skin and gut microbiota.
 
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 “There is clearly a change in the diversity and population of bacteria in those who get acne,” said Dr. Adam Friedman, an associate professor of dermatology at George Washington University who was not affiliated with the study. “It’s not like bacteria are bad or good, it’s that they’re good when everyone is where they’re supposed to be in the right concentration, that communities are in harmony with one another.”
 

 In those with acne, “there’s a decrease in diversity among organisms. There are certain types of bacteria in particular that are implicated in clinical disease,” Friedman said, including
 
 P. acnes
 
 and
 
 Staphylococcus
 
 , the proportions of which vary before, during, and after an infection.
 

 Both
 
 Staphylococcus
 
 and
 
 P. acnes
 
 have the ability to inhibit the growth of the other, leading to a sort of tug of war that can contain or cause acne breakouts.
 

 Years ago, Friedman said,
 
 P. acnes
 
 was considered a “bystander” when it came to acne infections because no one could figure out its role in the infection. It was simply always present during acne breakouts, giving the bacteria its name. Thanks to the recent advances in research, dermatologists and skin researchers now know it’s a main player.
 

 The study of the body’s bacterial harmony and its disruption was enabled by a technique known as 16S RNA sequencing, which is now heavily used in human microbiome research.
 

 Before 16S RNA sequencing, “we weren’t even able to study this,” Friedman said, “A lot of these organisms [in the human skin and gut microbiomes], you can’t even culture.”
 

 Though the sequencing technique was available decades ago, it has only been recently applied to microbiome research, said Nora Richter, a graduate student at Brown University who uses 16S RNA sequencing in her research.
 

 The sequencing technique is “gaining more momentum because sequencing methods are becoming cheaper,” Richter said. And cheaper costs mean more data for researchers to analyze, furthering the science of the skin.
 

 The sequencing method, she said, is used to identify the different bacterial species as well as how closely related those species are in a particular environment. In the case of recent acne research, the environments of the skin and gut.
 

 Though the science behind the pathology of acne is advancing, current acne treatment methods have yet to change. Current common acne treatments involve oral antibiotics or over-the-counter salicylic acid or benzoyl peroxide. For more serious cases, patients may incorporate isotretinoin into their routines, formerly known as Accutane.
 

 These treatments indiscriminately inhibit and prevent bacterial growth and don’t always lead to the restoration of healthy bacterial proportions in those who suffer from chronic acne.
 

 Marie-Ange Dagnelie, a graduate student at the University of Nantes, studies the microbiology of the skin. She thinks the recent advances in skin microbiome research could be used to develop new therapeutic approaches for treating acne.
 

 Understanding the connections between different skin bacteria, she believes, can influence future acne treatments. Dagnelie imagines a therapeutic approach that is able to restore healthy proportions of skin bacteria by using bacteria themselves.
 
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 Bacteria aren't the only cause of pimples—tiny mites may also be to blame.
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 This approach is similar to fecal transplants, where doctors transplant gut flora from healthy patients to those suffering from gastrointestinal infections. Such treatments have restored the healthy balance of bacterial populations.
 

 “I’m really convinced that in future years this will be a new treatment, especially in acne,” she said.
 
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 Photo credit: Public domain

By 2030, Earth’s Climate Could Look Like It Did 3 Million Years Ago

“Those who do not learn history are doomed to repeat it.” It’s an aphorism frequently cited for its relevance to social change—but it may apply to science just as well.In <a href="https://www.pnas.org/content/early/2018/12/05/1809600115">a study</a> published Monday in the Proceedings of the National Academy of Sciences (PNAS), scientists report that a planet-wide cooling trend that began nearly 50 million years ago is reversing due to <a href="https://www.pbs.org/wgbh/nova/video/decoding-the-weather-machine/">climate change</a>. According to the researchers, if current emission trends continue, then by 2030, Earth’s climate may resemble the <a href="https://www.sciencenews.org/article/what-pliocene-epoch-can-teach-us-about-future-warming-earth">mid-Pliocene epoch</a>, which lasted from 3.3 million to three million years ago. During that period, there were no large ice sheets in the Northern Hemisphere and sea levels were about 60 feet higher than present. The epoch also marked the dawn of hominid evolution.
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What’s more, the researchers found that—again, if current emission trends continue—Earth’s climate could plunge further into the past. By 2150, the planet could look something like the Eocene epoch, which began just after dinosaurs went extinct and was characterized by high carbon dioxide levels, gigantic volcanic eruptions, and the advent of the ancestors of modern mammals.In short, if our planet’s history were a movie, we’re currently pressing the “rewind” button.The study’s lead author, Kevin Burke, worked with paleoecologist Dr. John Williams of the University of Wisconsin-Madison to assess the climatic characteristics of several geologic time periods, including the Early Eocene (beginning 56 million years ago), the mid-Pliocene (beginning 3.3 million years ago), the Last Interglacial (beginning 130,000 years ago), the mid-Holocene (beginning 7,000 years ago), the pre-industrial era (beginning in 1750), and the early 20th century.Using several climate scenarios put forth by the IPCC Fifth Assessment (the fifth in a series of reports from the United Nations and the World Meteorological Organization designed to assess scientific information on climate change)—including one known as “Representative Concentration Pathway 8.5” (RCP8.5), which paints a picture of a future sans climate mitigation attempts (what climate scientists call the “business-as-usual” scenario), and RCP4.5, which depicts a future in which we’ve moderately reduced emissions—Burke and Williams compared years-from-now conditions across every inch of the planet to the past.“I think one of the real challenges of 21st century climate change is that it’s very hard for us to imagine what the world looks like when it’s 2 degrees warmer or 4 degrees warmer, or it’s outside of anything we’ve seen in our history,” Williams said. Having this data is therefore helpful—we can better visualize what our home will be like decades and even a century from now. From these past climate conditions, we can start to draw comparisons and analogies to help conceptualize the climates we can expect in the coming decades.
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“One of [our goals] is to place future climates in better context of the past,” said Burke, a PhD candidate at the University of Wisconsin-Madison’s Nelson Institute for Environmental Studies. He says researchers have previously uncovered “climate matches,” but in a more informal, generalized way. In this study, Burke and Williams analyzed all projected decade-by-decade climate simulations for the future and juxtaposed them with simulations of past time periods included in the study. “We’re sort of extending the baseline of what we’re comparing the future to, and we’re doing it in a quantitative manner,” Burke said.They found that under a “business-as-usual” scenario, Earth’s climate starts to become like the Eocene’s beginning around the year 2100. “That’s really striking,” Williams said. “That’s, of course, a long time back—back when whales and horses started to evolve.” However, under moderately reduced emissions, it stabilizes at mid-Piocene-esque climes. The researchers hope to investigate a greater variety of scenarios—beyond just RCP8.5 and RCP4.5—in the future."These are terrifying projections,” said <a href="http://sarahmyhre.com/">Dr. Sarah Myhre</a>, a research associate at the University of Washington’s School of Oceanography and a leading voice in the field of climate science communication. “They show that there are landscapes that are more vulnerable than others—risk is not equally distributed.” She also noted the study’s finding that deep-geological climate matches first appear in the centers of continents and then expand outward. In other words, Madison, Wisconsin warms up more than Seattle, Washington under these projections—despite the fact that they’re at the same latitude.The study also identified that under the “business-as-usual” scenario, so-called “novel” climates with no close matches in the six past time periods would emerge across nearly 9 percent of the planet. Burke said these novel climates are “essentially so different from anything in the baseline that none of the time periods in our assessment provided a close analog for that place in the future.” Many of the climates Burke and Williams classified as novel tended to be in monsoon-prone areas of the globe, like the tropics or other regions that experience extremely high levels of precipitation. “You can imagine things either warming beyond comparison of the already warm climates, or things getting extremely wet or extremely dry, and just not having any similar climates in that baseline,” Burke said.
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Myhre found that particular result compelling. “I think the ‘novel climate’ finding under the ‘business-as-normal’ emission trajectory is a significant finding.”Many of the climates Burke and Williams classified as “novel” tended to be in monsoon-prone areas of the globe, like the tropics or other regions that experience extremely high levels of precipitation. “You can imagine things either warming beyond comparison of the already warm climates, or things getting extremely wet or extremely dry, and just not having any similar climates in that baseline,” Burke said.Believe it or not, 9 percent is actually low compared to prior estimates; other quantitative assessments have compared climate projections to solely the modern era at the exclusion of deep geologic time. Such analyses, according to Burke, “saw a higher prevalence of novel climates for the same types of high-end emission scenarios” because the smaller sample size equated to a lesser chance of finding close matches. By studying a greater number of potential close matches, Burke and Williams saw the number of climates classified as “novel” go down.Does the rarity of these novel climates make them scarier than ever before?“Pliocene and Eocene are quite scary enough,” Myhre said. Plus, “changing temperature and precipitation are physical measurements, but what they produce are vast reorganizations” of biology and culture.Burke agrees that the implications of this study are urgent. “This is a problem we’re facing now,” he said. “This paper is showing us that within the next couple of decades, if we continue to emit greenhouse gases at an unmitigated level, we’re going to be seeing climates that more commonly resemble time period like the Pliocene than the pre-industrial. We’re well on our way toward that future.”

A planet-wide cooling trend that began nearly 50 million years ago is reversing due to climate change, scientists report.

Drone Monitoring of Volcanoes Could Improve Warning Times

After two eruptions in the span of a month, the public is suddenly paying attention to volcanoes. But volcanologists have been watching them for years, and now, a small group is taking volcano monitoring to new heights with the help of drones.


 The team’s efforts couldn’t be more timely. In Guatemala, the death toll has risen to 69 in the wake of a violent eruption of Volcán de Fuego, which sent billowing black clouds of searing-hot gases and rocks into the air and flowing over the land. And over in Hawaii, a magnitude 5.5 earthquake recently rocked the ongoing Kilauea eruption, reminding residents that the disaster is far from over.

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 Knowing in advance what kinds of eruptions will occur and what danger they pose requires diligent work. The Earth currently has approximately 1,500 active volcanoes, dozens of which are actively erupting at any given moment. Drones, also known as unmanned aircraft systems (UAS), can help volcanologists keep closer tabs on the dangerous geologic features.


 For United States Geological Survey volcanologist Angie Diefenbach, Kilauea marks the agency’s first “eruption response using UAS.”


 At Kilauea, Diefenbach and her colleagues use drones to track lava flow paths, produce elevation models of the changing landscapes, take thermal images, and track the gases released at active sites.


 A NOVA producer reports from multiple Kilauea fissures.


 Diefenbach and her colleagues aren’t alone. Scientists around the world are using drones to improve our understanding of volcanoes. Maarten de Moor, a volcanologist at the Observatorio Vulcanológico y Sismológico de Costa Rica studies volcanic gases. Traditionally, volcanologists like de Moor install monitoring instruments at active sites to study how the gases change over time. But this comes with a catch: though they’re great for long-term monitoring, those instruments aren’t quite permanent if the volcano actually erupts.


 “When the volcano erupts, it destroys the instrument,” de Moor said, “and then you can’t go into the crater because it’s too dangerous to put in a new instrument. You don’t know what’s going on because you don’t have any data, and that’s where the drones come in.”


 Flying a drone into a volcano is no easy feat—it takes entire teams of researchers to perform successful flights. Researchers have to consider many technical details such as whether drones can be equipped with lightweight scientific instruments that can measure gases from the sky and successfully fly with the added weight. They also have to consider power: drone batteries tend to lose charge quickly, so scientists have to plan and time their flights carefully.


 “During the flights, things are happening so quickly, with the drone disappearing into clouds of volcanic gas, gusts of wind pushing it around, and weather conditions changing extremely quickly,” de Moor said. “Every minute seems like an eternity because you are always wondering if the drone will make it back.”

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<h2>
 Life-Saving Data
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 Monitoring volcanoes by drones won’t replace traditional monitoring methods, but will supplement them, giving researchers potentially life-saving data during potentially life-threatening situations.


 John Stix, a volcanologist and professor at McGill University in Montreal, Canada, was part of one of the first groups that measured gases emitted by active volcanoes with drones. In 2016, Stix and his colleagues took two drones to Central America to measure gases at actively erupting volcanoes. There, they soon came across the grim reality of flying drones in dangerous conditions.


 “We crashed a drone,” Stix said. “It’s just part of the business.”


 Stix and his colleagues used what they learned from their crash to prepare for the next flight, which involved learning how to better operate the drone in the plume and enhancing the instrumentation they used for gas measurements on the drone. In April 2017, Stix and his colleagues successfully flew a drone at Turrialba, an active volcano in Costa Rica, and the data they gathered adds to the growing research around the volcano.


 “Right now, in 2018, the volcano is probably as active as it has ever been,” Stix says. “The big question is what’s going to happen next.”


 But predicting the activity of volcanoes is very difficult, said Janine Krippner, a volcanologist and postdoctoral researcher at Concord University in Athens, West Virginia.


 “Every volcano has its own kind of personality, and they have different moods,” Krippner said. “A volcano won’t necessarily produce the same kind of eruption over and over…An active volcano is an evolving system, it’s constantly changing.”


 For example, if a volcano starts to emit more gas over shorter periods of time, “the situation is escalating and it’s probably going to lead to an eruption—and the big question is how big that eruption is going to be,” de Moor said. That sort of information, collected by long-term monitoring and drones, could inform warnings and evacuations in the communities around volcanoes, potentially saving lives.

<h2>
 Sharing Information
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 But how quickly that information makes it to those on the ground varies depending on local governments.


 Amy Donovan, a lecturer at the University of Cambridge, studies how volcano research translates to policy. “You can go and fly a drone around a volcano, but if you’re not passing that information on to somebody who can do something about it, then it’s not going to have any impact at all,” she said.


 To ensure data is shared and used, researchers who fly drones might work with local volcano observatories, which, Donovan says, “know better than anybody else what’s going on” with their volcanoes. But, she adds, drones might have an unexpected added benefit: engaging the communities that live around volcanoes.


 “Showing people the volcano through the eyes of a drone can give them a new kind of insight into their home territory,” Donovan said, “And also just a sense that the volcano is maybe a bit more alive than they thought it was.”


 Still, those benefits are limited to a small number right now: “There are plenty of volcanoes globally that are still not really monitored very well,” Donovan says.

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 Loÿc Vanderkluysen, an assistant professor at Drexel University, uses drones in his volcano research and imagines a future in which drones could help fill in missing data about volcanoes around the world—without the need for human operators.


 “[It] sounds like science fiction, but the development of drones as unmanned and autonomous vehicles means that we could potentially program drones to learn [about the] behavior of a volcano and be able to feed the detection,” Vanderkluysen says. “Then the drone would be able to launch by itself, go make the measurements by itself, land back to the base by itself, and upload the data itself without human interaction.”


 Though drones have been used in volcanology research in only the past few years, volcanologists are only just getting started.


 “I think [drones] are going become unavoidable because of the aspect that they can go in hazardous places where volcanologists shouldn’t go and collect data in places where we never have before,” Vanderkluysen says. “I think we’re going to be accessing data about volcanoes that we never dreamed of.”


 Photo credit: Orlando Estrada / Contributor, Getty Images

Drones can go where volcanologists can’t, giving researchers access to potentially life-saving data.

Certain myths about left-handedness persist. What is fact versus fiction?

Inside the mind of a left-hander

Editor’s Note: This article was <a href="http://app.nationalproduction.wgbh.org/e/es.aspx?s=2531&amp;e=1085740&amp;elqTrackId=87bceb0e8d45455b8e6ff9d7c932edc8&amp;elq=ab7340fe4f4649e4a54c3edee23fa2a4&amp;elqaid=5363&amp;elqat=1">originally published</a> in an edition of NOVA’s email newsletter, NOVA Lens, and has now been repurposed for NOVA Next. Sign up for NOVA Lens <a href="http://www.pbs.org/wgbh/nova/newsletters.html">here</a> (select “NOVA Newsletters”).It’s back-to-school season, and, for the first time, some parents will discover that their children are left-handed.Doesn’t sound like a big deal, right? That’s probably because times have changed.
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Until the second half of the 20th century, it wasn’t uncommon to hear about parents and teachers coaxing lefties into using their right hand for daily tasks including writing, eating, and teeth-brushing. In most parts of the world, that’s no longer a standard practice—but <a href="http://app.nationalproduction.wgbh.org/e/er?s=2531&amp;lid=7119&amp;elqTrackId=866958B6497C3E761332AD51357D8B97&amp;elq=ab7340fe4f4649e4a54c3edee23fa2a4&amp;elqaid=5363&amp;elqat=1">certain myths</a> about left-handedness persist. The truth is that left-handedness is much more than a trivial paw preference: It may be a useful lens through which to examine brain development.<h2>About One in Ten</h2>Patricia Cowell, a professor of cognitive neuroscience at the University of Sheffield in the United Kingdom, stresses that though left-handedness is referred to as “atypical” from time to time, there’s no need for concern.“It’s lower prevalence. It’s not an anomaly; it’s not anything negative as such. It’s just different from the majority,” Cowell said. “I think the thing that’s really important is that it is a very constant biological variation within normal development.”Cowell studies handedness and brain lateralization: how different abilities like language or visual processing are organized within the brain. “If someone is left-handed, their brain organization is going to be different than someone [who] is right-handed,” Cowell said.Before the era of the laptop-filled lecture hall, Cowell would sit at the front of the room and count the number of lefties in her classes while students completed five-minute thought experiments. Although the small sample size caused some variation from class to class, around 1 in 10 students were left-handed. This distribution is present in the general population as well—it is thought that around 10% of people around the world are left-handed. “It’s pretty stable,” Cowell said. “You need a fairly big group of people to get a consistent number, but I think that you can always find a few in a big group.”
And there’s some evidence that the distribution of handedness has lasted for thousands of years, with <a href="http://news.bbc.co.uk/2/hi/science/nature/3485967.stm">right-handers in the strong majority</a> and left-handers comprising a mere fraction. To study examples of handedness in history, French researchers examined Western European cave artwork dating back 10,000 to 30,000 years. Ancient artists would hold their non-dominant hands against a rock wall and use their dominant hand to blow colored dust onto it using a blowing tube, creating a negative image of their hand on the rock. The distributions of handedness found in cave art is consistent with what we see today.Other species have demonstrated handedness, as well. Roel Willems is a senior researcher at the Centre for Language Studies and the Donders Institute for Brain Cognition and Behaviour in Nijmegen in the Netherlands.“Other animals also tend to have a handedness preference,” Willems said. “[But] there is no other species [other than humans] that seems at the population level to be so strongly biased.”So far, research hasn’t revealed why the distribution of handedness has stood the test of time. It’s all “one big mystery,” according to Willems.But that could change. Scientists like Willems and Cowell are working to understand lefties’ unique brain structure—and what that could potentially tell us about brain organization and our evolution as a species.
<h2>All in the Head</h2>Handedness is sometimes obvious, and it’s closely tied to our ability to perform complex tasks every day. But to truly study handedness, researchers have to look to the brain.For example, development across the brain’s motor cortex—the part of the brain responsible for voluntary movement—varies in relation to handedness. To study the motor cortex, researchers often look at how much oxygen is being consumed in parts of the brain during tasks via fMRI, or through a different technique that assesses connections within the nervous system called transcranial magnetic simulation (TMS). Using these techniques, researchers have identified connections between cortex development and handedness.
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To truly study handedness, researchers have to look to the brain.
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“The left part of the motor cortex is more developed in right-handers than the right part of their motor cortex,” Willems said. “This imbalance we also find in left-handers. So, in left-handers, the right part of the motor cortex is better developed. But, the imbalance is much less strong.”If motor cortex development differs based on handedness, then what would happen if a person suddenly lost the ability to use his or her dominant hand? In that case, it turns out lefties might have an advantage.“A typical phenomenon that you see with left-handers is that they are much more capable of doing stuff with their non-preferred hands,” William said. “When you break [the dominant] arm, you have to brush your teeth with your non-preferred hand. I don’t know if you’ve ever tried it, but that’s painful. Left handers have the advantage—if they break their left arm, it’s less painful if they have to [brush] with their right arm than for right-handers [brushing with their left arm].”Beyond movement, other brain functions like the ability to recognize faces are also tied to handedness and brain organization. While it was thought that face recognition was strongly right-lateralized, Willems said, his research has shown that it’s also less strongly lateralized in lefties.And some abilities, like language, might have lateralization that can’t always be predicted using handedness. For serious surgeries like tumor removal, “a neurosurgeon will always test the language lateralization before he starts to operate because you cannot simply assume that that lateralization is left or right,” Willems said. But in emergency situations where cortical mapping and fMRI aren’t available, “handedness might clue [surgeons] into a patient’s brain hemisphere dominance,” Abdul-Kareem Ahmed, a neurosurgery resident at the University of Maryland, said.<h2>No Longer Left Out</h2>Historically, some researchers avoided left-handed subjects in neuroscience and psychology studies because the lefties could complicate the results. They’d prefer to have a homogeneous set of right-handers instead. (“It’s almost a mundane reason, but that is why,” Willems said.) <a href="https://www.nature.com/articles/333213b0">One study</a> on left-handers from 1988 contributed to the myth that left-handers have a lower life expectancy than right-handers.“That is probably not true,” Willems says. “The good news is that this has gotten a lot of attention, and in the end, it was very likely that it was based on a statistical error.”
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One study on left-handers from 1988 contributed to the myth that left-handers have a lower life expectancy than right-handers.
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More reputable research began in the late 20th century, and continues today. In addition to examining the connections in the brain to handedness, researchers are now turning to genetics to demystify the origins of handedness in the first place.“Some people seem to be born left-handed, so there is a genetic component,” Willems said. However, he notes that the research on how exactly that works is in progress. Cowell describes the development of handedness as a sort of positive feedback loop: “Presumably, there is going to be some environmental influence early on. It could be prenatal, it could be early postnatal, but once the person is in a position where they’re developing along a trajectory where they have the capacity to become a left-hander, then by virtue of being left-handed, that is in itself an influence on the brain.”Further, if someone is naturally left-handed but forced to use their right hand, then their brain might reflect experience-dependent changes. Although it differs enormously by geographic region, there have been studies in which left-handed subjects were forced to use their right hands. Their resulting brain scans showed something striking. “In terms of lateralization of the motor functions, they are sort of half in between the right and left halves,” Willems said. In other words, their motor cortex development imbalances were in between those of left and right-handers.With the advent of rapid and affordable genome sequencing, researchers may get closer to understanding the genetics and origins of handedness and craft a better understanding of lateralization—all with the help of lefties. By including left-handers in studies with right-handers, genetic differences between the two could be more apparent. “Otherwise, you’re looking at a system which has very minute variations, and it’s hard to find genes that correlate with those variations because they are simply too small,” Willems said.Now, lefty brains are changing the ways scientists think about brain organization. Previous understandings of brain organization based on right-handers only may have set up the illusion that evolution led to a one-size-fits approach to wire the brain.“However, if by-and-large 10% of people do it slightly differently, that tells you that the brain is perhaps more plastic in how it can be wired,” Willems said.This article was written and edited by lefties.
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Photo credit: <a href="https://upload.wikimedia.org/wikipedia/commons/thumb/0/02/Left-handed_writing_with_wristwatch.jpg/2048px-Left-handed_writing_with_wristwatch.jpg">Alejandro Escamilla / Wikimedia Commons (CC0 1.0)</a>

Left-handedness is much more than a trivial paw preference: It may be a useful lens through which to examine brain development.

Molecular Fossils Offer Universal Way to Track Climate Change

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 Lurking beneath the surface of Inner Mongolia’s striking saline lakes are a potential Rosetta stone of paleoclimate.
 

 Jingjing Li and her colleagues from the Nanjing Institute of Geology and Limnology and the University of Bristol studied the lakes and characterized the bacteria that produced branched GDGTs, a fatty record of Earth’s climate history.
 

 So far, scientists have used branched GDGTs to create temperature records for temperate, arctic, and tropical environments. Branched GDGTs are what scientists call temperature proxies—data drawn from them can be used to calculate historical air temperatures. But that hasn’t been quite possible in saline environments until now.
 
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<figcaption>With a record spanning thousands of years, long dead bacteria—from lakes such as this one in Mongolia—may help scientists predict future climate trends around the world.
 
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 While some molecular fossils allow researchers to create climate records only in lakes, oceans, or soils, GDGTs are so prevalent, in fact, that you’d probably find them in a handful of dirt from your neighborhood park. Branched GDGTs found in Mongolia could generate a climate record similarly to the way they would elsewhere on Earth. This allows scientists to draw accurate comparisons of how the temperature changed in different regions over time.
 

 “In order to understand future climate change, scientists look at past climate change to understand the climate system,” said David Naafs, an organic biogeochemist involved in the study. He looks at branched GDGTs and uses molecular fossils to construct past environmental conditions. Li applied his refined mathematical formula to turn data drawn from the branched GDGTs samples into temperature values.
 

 “One of the main challenges is that we do not know [which bacteria are] producing [branched] GDGTs” Naafs said. “This is really a key step that the community needs to make, but it has been very difficult so far.”
 

 Li’s study revealed something that may help elevate efforts to identify the bacteria that produce branched GDGTs.
 

 Previous studies of lakes in different environments showed that branched GDGTs were produced by bacteria that lived in the lake waters. That’s not quite the case in Inner Mongolia, according to the study.
 

 Li and her colleagues found that the branched GDGTs in saline lakes came from bacteria that lived in the soils around the lake. Instead of being produced in the lake waters themselves, most branched GDGTs were deposited into lakes when the surrounding soils were blown, kicked, or washed into the lake.
 

 That sort of information can help researchers interpret the historical temperatures and how they changed over time. This could mean that the salt content of the waters affects how the bacteria grow and produce GDGTs. Even further, it may help climate scientists decide where to sample for branched GDGTs in future efforts involving the previously understudied region.
 

 “When we generate temperature reconstructions, sometimes, [records] look beautiful, [or] sometimes nonsensical. Right now, we don’t know why,” said Jim Russell, a paleoclimatologist at Brown University.
 

 Understanding where the GDGTs were produced may help explain. It also may help scientists predict future temperature trends.
 

 As climate researchers model Earth’s future climate outlook, the pressure is on geoscientists to create reliable climate records that can be used in climate models. The more accurate and plentiful the data available, the more reliable the model.
 
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 Photo credit:
 <a href="https://commons.wikimedia.org/wiki/File:Badain_Jaran_Temple_Reflection.JPG">
 Sjoerd van Oort / Wikimedia Commons (CC BY-SA 3.0)
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Mars’s dusty red surface is awaiting careful scientific analysis—and the results could be incredibly exciting. | Photo credit: NASA/JPL/USGS

In 2020, the Latest Mars Rover Will Land on Jezero Crater

Editor’s Note: This article was <a href="http://app.nationalproduction.wgbh.org/e/es.aspx?s=2531&amp;e=1152702&amp;elqTrackId=87bceb0e8d45455b8e6ff9d7c932edc8&amp;elq=fb21807031e74bc3aea5eaf4fe7f2bda&amp;elqaid=5602&amp;elqat=1">originally published</a> in an edition of NOVA’s email newsletter, NOVA Lens, and has now been repurposed for NOVA Next. Sign up for NOVA Lens <a href="http://www.pbs.org/wgbh/nova/newsletters.html">here</a> (select “NOVA Newsletters”).Today marks the Northern Hemisphere’s winter solstice. Millions of miles away from Earth, Mars’s northern hemisphere is already well into its winter.On the eve of the <a href="http://app.nationalproduction.wgbh.org/e/er?s=2531&amp;lid=7756&amp;elqTrackId=5EBD0E5434E7BF82460E4063D17D399A&amp;elq=fb21807031e74bc3aea5eaf4fe7f2bda&amp;elqaid=5602&amp;elqat=1">Martian solstice</a> this October, scientists from around the world began to gather in Glendale, California, for the fourth and final Mars 2020 Landing Site Workshop. Over the following three days, they discussed the merits and potential scientific opportunities of four candidate landing sites—Columbia Hills, Northeast Syrtis, Midway, and Jezero crater—for the next Mars rover, <a href="http://app.nationalproduction.wgbh.org/e/er?s=2531&amp;lid=7755&amp;elqTrackId=799B715C4FF581283C7E00797AEBE4BD&amp;elq=fb21807031e74bc3aea5eaf4fe7f2bda&amp;elqaid=5602&amp;elqat=1">Mars 2020</a>, which is slated to launch from Earth in July or August of 2020 and will land in February 2021. The latter three were candidates for the Mars Science Laboratory Curiosity Rover, which landed in landed in 2012 at a different site, Gale Crater.
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At the workshop, scientists presented their analyses and opinions of certain sites and engaged in lively debates with workshop participants both in person and online. At the end, 158 scientists in attendance (full disclosure: I was one of them) voted on the four sites, ranking each in accordance to mission criteria. The rankings would help inform the final decision, to be announced before the year’s end.Around lunchtime on November 19th, a month into the Martian winter, a NASA teleconference on the Mars 2020 rover’s landing site was set to begin. Tim Goudge, a planetary scientist and postdoctoral fellow at University of Texas at Austin, had spent the last four years becoming one of Jezero crater’s most well-known advocates in the Mars scientific community. When it came time to listen to the announcement, Goudge opted to lay low, rather than congregate with everyone else in his department who was listening.“I decided I’d rather just sit in my office and listen to the news and try and soak it all in,” Goudge says. When he left the workshop in Glendale a month earlier, he wasn’t sure which way the final decision would go: “I was pretty much 50-50 on whether or not it was going to be Jezero.”When the teleconference began, the decision was announced immediately: Jezero crater would be the landing site for the Mars 2020 rover.The 28-mile-wide crater is located on the western margin of the Isidis Planitia region in the northern hemisphere of the Red Planet and once hosted a lake nearly 820 feet deep, fed by a nearby ancient river delta. The resulting Jezero catchment today may contain a rich archive of the Martian past, including the clay minerals and some of the oldest crustal materials on the surface of Mars.
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“Those materials have been picked up and moved and collected all in one place at this deltaic deposit,” Goudge says, making Jezero a convenient location to study a diverse set of mineral deposits from around the site. Carbonate minerals at the site could also help track the evolution of the Martian atmosphere over the planet’s historyFor the astrobiologically-inclined, Jezero crater is a tantalizing place to search for evidence of ancient life on Mars. “I think that has to be the hands-down most exciting thing that this site has to offer,” Goudge says. In fact, finding out whether Mars hosted life and whether it was ever habitable in the first place is one of the key goals of the new rover’s mission.“Delta environments on Earth are very good at collecting and concentrating organic matter,” Goudge says. “Going to look at those parts of the outcrop to see if there’s any indication of biosignatures from potential ancient Martian biosphere is really, really exciting, and will be an incredible exploration feat.” Earlier this year, the Sample Analysis on Mars instrument, part of the Curiosity Rover, <a href="http://app.nationalproduction.wgbh.org/e/er?s=2531&amp;lid=7757&amp;elqTrackId=86F942649F344C789C8546BAC2163698&amp;elq=fb21807031e74bc3aea5eaf4fe7f2bda&amp;elqaid=5602&amp;elqat=1">detected three-billion-year old organic molecules in Martian mudstones</a>. But their origins—whether they’re derived from living things or not—can’t be determined using Curiosity’s instrumentation.That’s where the Mars 2020 rover comes in. While some of the science analyzing the deposits at Jezero will be done on site, other analyses will occur on Earth. Tiny cores will be drilled from the Martian surface and cached for return to Earth through a later mission. Kennda Lynch, a postdoctoral researcher and astrobiologist at the Georgia Institute of Technology, studies the geobiology of saline-rich paleolake sediments on Earth as analogs for ancient lake systems on Mars."There’s no one smoking gun test that tells us that something’s biogenic,” or produced by living organisms, Lynch says. “That’s exactly the reason why we need to bring samples back, because we can’t do all the tests that we need to do [on Mars].”Analyses of Martian samples in labs on Earth would not only be more detailed and complex, but could also help refine our estimates of the ages of geologic features on planetary surfaces. Currently, the ages of planetary surface features throughout our solar system are determined by a method called crater counting, which assumes that planets begin without impact craters and accumulate them over time. By estimating the rate at which the craters accumulated, scientists calculate ages of features, which are currently calibrated using ages of samples from Luna- and Apollo-era Moon missions. Bringing back samples from Mars could further that calibration.“It will actually help calibrate our understanding of cratering rates for all the planetary bodies in our solar system,” Goudge said.
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Deposits at Jezero also “preserve critical information that can help us reconstruct paleoclimate,” Lynch says—and they could give scientists a glimpse of how climate changed over time on Mars.“I think we’ve chosen a really great site,” Lynch says. “I’m excited for all the work that we’re going to be able to do in the next few years to try to choose the best samples and best data to bring back to Earth to try to understand life on Mars.”

Martian samples from the Jerezo creater could help refine our estimates of the ages of geologic features on planetary surfaces.

Fatima Husain

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