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<p>
 Archaeological discoveries have changed what we know about tyrannosaurs—they had
 <a href="http://www.pbs.org/wgbh/nova/next/evolution/scientists-find-feathered-dino-tail-inside-99-million-year-old-amber/">
  feathers
 </a>
 and ran like birds. Now, a new species that roamed in Montana 100 million to 66 million years ago has given us our first insight into what these dinosaurs’ faces might have looked like.
</p>
<p>
 A typical
 <i>
  Daspletosaurus hornei
 </i>
 is about 30 feet long and 7 feet tall, with a large skull covered in bony ridges and different skin types, according to Thomas Carr, a paleontologist from Carthage College, and his team.
</p>
<p>
 In their paper in
 <a href="http://www.nature.com/articles/srep44942#s3">
  <i>
   Scientific Reports
  </i>
 </a>
 , they write that
 <i>
  D. horneri
 </i>
 is “critical to understanding the evolutionary transition from non-beak to beak along the line to birds, since beaks are specialized epidermal structures,” meaning the skull gives us a glimpse at the in-between stages between snouts and beaks.
</p>
<p>
 Researchers examined the textures of a well-preserved skull and reconstructed what kinds of tissues and systems of nerves covered them. They also had access to a massive database of tyrannosaur bones that they used for comparison to rule out any damage that might have happened during fossilization.
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 Once the researchers completed their texture analysis, they compared it to modern animals who show nearly identical patterns: birds and crocodiles. Here’s Annalee Newitz reporting for Ars Technica:
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 Immediately, they found that the tyrannosaur’s lower jaw showed evidence of having “neurovasculature that is also seen in birds.” Specifically, it seems that
 <i>
  D. horneri
 </i>
 had a trigeminal nerve, an ancient piece of anatomy found in many animals whose faces are highly sensitive to vibration, infrared radiation, electricity, and even magnetic fields.
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 The trigeminal nerve would have been connected to a highly sensitive flat scale on the dinosaur’s nose and around its mouth. Each of these scales would’ve been densely packed with nerves—integumentary sensory organs (ISOs)—that could transmit “high resolution tactile sensations from the skin, making their snouts more sensitive than human fingerprints.”
</p>
<p>
 According to the researchers, ISOs might’ve helped in a variety of ways. They could have helped tyrannosaurs detect optimal nest temperatures, harmlessly pick up eggs, and even engage in foreplay. During courtship, they might have rubbed their sensitive faces together to stimulate those nerve endings. That such hulking creatures could engage in such subtle sexual behavior is remarkable, and may suggest that we have a lot more to learn about these ancient beasts.
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 Photo credit:
 <a href="https://www.flickr.com/photos/kansasphoto/16507782409/">
  Patrick Emerson / Flickr (CC BY-ND 2.0)
 </a>
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<p>A new tyrannosaur species&#x27; faces might’ve been scaly and densely packed with sensitive nerves.</p>

New Tyrannosaur Species Had a Super Sensitive Face





  
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 <p>
  We’ve known for some time that honey bees are on the decline—an alarming statistic considering that they pollinate many, if not most, of the fruits and seeds we consume. And unfortunately, new research is not bringing any good news.
 </p>
 <p>
  Alexandre Aebi from the University of Neuchatel in Switzerland and his colleges gathered 198 honey samples from every continent but Antarctica and looked for signs of neonicotinoids—the world’s most widely used class of insecticides. Crop seeds are coated in these chemicals, which are then incorporated into the plant’s tissues, reducing the need for spraying. In general, they are considered less harmful to the environment than older products.
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            <figure class="richtext-image full-width"><img alt="bees_honeycomb" class="richtext-image full-width" height="449" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/bees_honeycomb.width-800.jpg"/><figcaption>
  Seventy-five percent of honey sampled from around the world contained trace amounts of popular insecticides.
 <div class="credit"></div></figcaption>
            </figure>
            
 <p>
  Yet the researchers found that 75% of the honey samples contained trace amounts of at least one of these chemicals. The highest concentrations were in honey samples from North America, Asia, and Europe. That European honey contains neonicotinoids is a bit of a mystery considering that there’s been a ban on these products since 2013.
 </p>
 <p>
  Furthermore, of the honey samples that had neonicotinoids, 34% had levels high enough that could be detrimental to bees. Even at the elevated levels, the honey is still safe for human consumption.
 </p>
 <p>
  Neonicotinoids don’t break down easily in the environment, meaning they’re often found in soils, water samples, and wildflowers.
 </p>
 <p>
  Here’s Matt McGrath reporting for BBC News:
 </p>
 <blockquote>
  <p>
   Industry figures though are critical of the study pointing out that it is hard to draw conclusions from just 200 hundred samples.
  </p>
  <p>
   “Setting aside the sample size of the study not being large enough to be representative, the fact that a residue is found is not in itself a cause for concern,” said Graeme Taylor, director of public affairs at the European Crop Protection Association, which represents the manufacturers of neonics.
  </p>
  <p>
   “In relation to the findings of the study more specifically, the reported residue levels are minuscule and well below human safety limits.”
  </p>
 </blockquote>
 <p>
  To protect honey bee populations, the authors of the study are proposing permanent ban, similar to the one that’s been floated in France.
 </p>
</section>
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 Photo credit:
 <a href="https://www.flickr.com/photos/foto_olio/14572174681">
  Riccardo Meneghini / Flickr (CC BY-NC-ND 2.0)
 </a>
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Honey Found to Contain Pesticides Implicated in Bee Population Collapse





  
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  One of Iceland’s most active volcanoes, Bárðarbunga, shook the earth four times in recent weeks, an indication it’s getting ready for eruption. Since part of it sits under an ice cap, an eruption could impact areas beyond the island.
 </p>
 <p>
  The earthquakes—measuring magnitudes of 3.9, 3.2, 4.7, and 4.7—are an ominous sign—pressure in the magma chamber below the volcano is likely building to a breaking point. Geologists warn that the volcano is poised to erupt, though they don’t know when it will happen or how significant it will be.
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            <figure class="richtext-image full-width"><img alt="Bárðarbunga_Volcano,_September_4_2014_-_15146259395" class="richtext-image full-width" height="450" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/bardarbunga_volcano_september_4_2014_-_1514625.width-800.jpg"/><figcaption>
  One of Iceland’s most active volcanoes experienced four large earthquakes, indicating it’s getting ready for eruption.
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 <p>
  Despite Bárðarbunga’s remote location, the effects of its eruption could be felt well beyond Iceland. One-third of the system its a part of is covered by Europe’s largest ice cap, and volcanoes covered with ice can be highly explosive and produce lots of fine ash—which spews into the atmosphere and can affects larger areas. In 2010, when the Eyjafjallajökull volcano erupted, it threw ash miles into the atmosphere. For days, air travel throughout Europe ground to a halt—planes couldn’t risk flying through the engine-destroying ash cloud that stretched from Ireland to Russia.
 </p>
 <p>
  Bárðarbunga poses similar risks. Here’s Elaina Zachos, reporting for National Geographic:
 </p>
 <blockquote>
  <p>
   Eruptions under ice can trigger explosions by turning large volumes of ice into steam, and as magma hits the steam it explodes into fine particles that can shoot high into the atmosphere. Or, lava from an eruption could melt the ice and cause flooding, like that brought on by the Eyjafjallajökull eruption.
  </p>
 </blockquote>
 <p>
  Bárðarbunga’s most recent explosion was from August 2014 through February 2015, and it was the largest the country had seen in 200 years. Pollution—especially fine particulate matter that can be hazardous to breathe—blanketed western Europe.
 </p>
 <p>
  Iceland’s residents aren’t strangers to volcanic eruptions. On average, a volcano in the system erupts once every 50 years.
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  Scientists hunt for a mega-eruption that plunged medieval Earth into a deep freeze.
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</section>
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 Photo credit:
 <a href="https://commons.wikimedia.org/wiki/File:Bárðarbunga_Volcano,_September_4_2014_-_15146259395.jpg">
  peterhartree / Wikimedia Commons (CC BY-SA 2.0)
 </a>
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One of Iceland's Biggest Volcanoes May Be Poised for Eruption





  
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 <p>
  More than 200,000 saiga antelope died suddenly over the course of a couple weeks in 2015. Scientists blamed bacteria called
  <em>
   Pasteurella multocida
  </em>
  type B. But new research suggests the antelope already contained the organism in their bodies, and that unusual heat and humidity released the bacteria, causing them to multiply rapidly in the days leading up to the event.
 </p>
 <p>
  Over several hundreds of miles of central Kazakhstan, antelope began showing symptoms of blood poisoning, called hemorrhagic septicemia. Suddenly, they stopped eating. At first, one or two antelopes would die. But by the end of the seventh day, they were all dead.
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            <figure class="richtext-image full-width"><img alt="Saiga_tartarica (1)" class="richtext-image full-width" height="421" width="748"
            src="https://www.pbs.org/wgbh/nova/media/images/saiga_tartarica-1.width-800.jpg"/><figcaption>
  More than 200,000 saga antelope died suddenly due to bacteria—and warmer weather.
 <div class="credit"></div></figcaption>
            </figure>
            
 <p>
  <em>
   Pasteurella multocida
  </em>
  type B is so toxic that an infected animal doesn’t have time to show many symptoms. It normally lives in the antelope’s tonsils, but during the event, they quickly spread to the bloodstream, causing the hemorrhaging.
 </p>
 <p>
  The presence of bacteria alone is not enough to explain the mass death. So, Richard Kock from The Royal Veterinary College and his team developed models that looked into two other extinctions (1981 and 1988) caused by hemorrhagic septicemia. They analyzed environmental conditions like temperature, rainfall, wind, and vegetation. Here’s Merrit Kennedy reporting for NPR:
 </p>
 <blockquote>
  <p>
   “You have unusually high levels of humidity each day over that 10 day period. And by doing that we could really tease it out and get a significant correlation,” says Kock. That makes sense, he says, “because the bacteria in the tonsils, they’re quite close to the environment of the air and they then basically, presumably, respond to that change in atmosphere. And that triggers them to start growing.”
  </p>
 </blockquote>
 <p>
  Only 30,000 saigas in the region survived, and while they are rapidly recovering and breeding, scientists don’t believe they could survive another event like this.
 </p>
 <p>
  What’s more, evidence suggests that animals like reindeer and musk ox face similar risks due to abnormal weather patterns.
 </p>
</section>
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 Photo credit:
 <a href="https://commons.wikimedia.org/wiki/File:Saiga_tartarica_(cropped).jpg">
  Navinder Singh / Wikimedia Commons (CC BY-SA 4.0)
 </a>
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Unusual Weather May Have Caused Antelope Mass Death in 2015





  
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<p>
 Scientists digging in an Israeli cave uncovered a fossilized jawbone from what they believe is the earliest modern human found outside of Africa. The jawbone includes eight teeth—seven of which are intact. This changes the timeline of when
 <i>
  Homo sapiens
 </i>
 ventured out of Africa by about 50,000 years.
</p>
<p>
 Anthropologists previously believed that modern humans began leaving Africa 90,000 to 120,000 years ago. But the cave where the jawbone was discovered is thought to be occupied between 160,000 and 250,000 years ago. Israel Hershkovitz, a paleoanthropologist at Tel Aviv University, found the jawbone and suspected it was evidence of an earlier African exodus.
</p>
<p>
 To test that suspicion, Hershkovitz and his colleagues sent the jawbone on a world tour. First, it traveled to Austria where it underwent high resolution micro-CT scanning and then was compared with with 30 other specimens—which included Neanderthals,
 <i>
  Homo erectus
 </i>
 , and other
 <i>
  Homo sapiens
 </i>
 . In Australia, France, and Israel, they used dating techniques to determine the jawbone’s age.
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 Their results determined that the jawbone is between 177,000 and 194,000 years old—confirming the scientists’ hypothesis. Here’s Nicholas St. Fleur for The New York Times:
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 “We are now realizing that it was not one big exodus out of Africa in a given time period,” said Dr. Hershkovitz. “Rather, there was a flow of hominins coming in and out of Africa for at least the last half a million years.”
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 This is not the first time Hershkovitz has found modern human fossils. In 2010, he found 400,000-year-old teeth in Israel, and in 2015 he found a 55,000-year-old skull in the Israel.
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      <div class="rich-text">Photo credit: Gerhard Weber/University of Vienna
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Scientists uncover a jawbone between 177,000 and 194,000 years old—making it the earliest modern human anyone has ever found outside of Africa.

<p>Scientists uncover a jawbone between 177,000 and 194,000 years old—making it the earliest modern human anyone has ever found outside of Africa.</p>

Fossilized Jawbone Hints at a Much Earlier Exodus from Africa





  
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 <p>
  In a brief, blocky, but stunning video released recently, scientists have witnessed a powerful gene editing technique in action.
 </p>
 <p>
  CRISPR, also known as CRISPR-Cas9, is a tool that, in conjunction with an enzyme known as Cas9, modifies genes by cutting strands of DNA, allowing traits to be deleted or new ones to be inserted. It has the potential to make malaria resistant mosquitos, treat HIV in mice, and eliminate some genetic diseases, among other things. Like many biological processes, biochemists have had to tease out CRISPR’s details without ever directly seeing it.
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            <figure class="richtext-image full-width"><img alt="CRISPR (1)" class="richtext-image full-width" height="286" width="508"
            src="https://www.pbs.org/wgbh/nova/media/images/crispr-1.width-800.jpg"/><figcaption>
  Scientists use high-speed atomic-force microscopy to witness CRISPR clipping DNA in real time.
 <div class="credit"></div></figcaption>
            </figure>
            
 <p>
  For a molecular-scale video clip, it shows amazingly clear footage in real time of CRISPR breaking DNA in two.
 </p>
 <p>
  Osamu Nureki, author of the paper and accompanying video clip, has previously used X-ray crystallography to study Cas9’s structure. To do that, he and his colleagues would coax Cas9 into a crystalline form and then they bombard them with X-rays, inferring the structure by studying how the rays diffracted. The result was a static, computer-generated image.
 </p>
 <p>
  In this new study, Nureki and his team “filmed” CRISPR-Cas9 using a unique type of microscopy. Here’s Sarah Zhang for The Atlantic:
 </p>
 <blockquote>
  <p>
   His team used a technique called high-speed atomic-force microscopy, in which a tiny needle moves back and forth probing the shape of Cas9. The needle moves so fast that it produces a movie. “The result is fairly easy to understand,” says Hiroshi Nishimasu, one of Nureki’s collaborators on the paper. “People say, ‘Wow!’ It’s very simple.”
  </p>
 </blockquote>
 <p>
  When Nureki presented this video for the first time at a conference in Big Sky, Montana, there was reportedly a gasp from attendees in the room—a rare occurrence at scientific proceedings.
 </p>
</section>
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 Photo credit:
 <a href="https://www.nature.com/articles/s41467-017-01466-8">
  Mikihiro Shibata / Nature Communications
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New Video Shows CRISPR Cutting DNA in Two





  
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 <p>
  Most drugs are designed to latch onto one specific protein in one specific tissue. But that protein, or one close by, may perform a function in a different tissue. That’s one reason why drugs have off-target effects. This is usually a problem but researchers are finding some drugs are surprisingly effective against diseases they were never intended to target.
 </p>
 <p>
  For instance, researchers found that a handful of asthma medications, including one called clenbuterol, seem to lower a person’s risk of getting Parkinson’s disease.
 </p>
 <p>
  Parkinson’s disease occurs when a specific group of neurons die. These neurons help control muscle activity and as they die off, people progressively lose control of their voluntary muscles until they suffer from uncontrolled tremors. Like other neurodegenerative diseases, Parkinson’s has been associated with malformed proteins that become tangled and accumulate in the dying cells.
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            <figure class="richtext-image full-width"><img alt="brains" class="richtext-image full-width" height="499" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/brains.width-800.jpg"/><figcaption>
  Tracking brain changes in people with Parkinson’s: researchers find that drugs that activate the adrenaline receptor seem to lower a person’s risk of getting Parkinson’s disease.
 <div class="credit"></div></figcaption>
            </figure>
            
 <p>
  Researchers have identified that Parkinson’s tangles are made from a protein called α-synuclein. People with extra copies of this gene are more susceptible to developing Parkinson’s later in life. So, researchers decided to look for drugs that may suppress this gene.
 </p>
 <p>
  A large international team of researchers examined over 1,000 drugs and potential drugs, and identified 35 that may lower the expression of the gene. Three of them reduce the activity of α-synuclein.
 </p>
 <p>
  Most of the chemicals in the drugs activate adrenaline receptors, which should also reduce α-synuclein levels. Conveniently, these chemicals are already used in asthma medications since adrenaline helps relax the muscles in our airways.
 </p>
 <p>
  The medications the researchers tracked varied from salbutamol (people who received this medication were two-thirds less likely to be diagnosed with Parkinson’s) to propranolol, which is typically used to calm irregular heartbeats and high blood pressure by blocking activation of adrenaline receptors. People who took this medication were two times more likely to be diagnosed with Parkinson’s.
 </p>
 <p>
  Not only did researchers study the effect of current medications, but they also looked at what happened to stem cells treated with these drugs. Here’s John Timmer reporting for Ars Technica:
 </p>
 <blockquote>
  <p>
   [The] authors obtained cells from an individual that carries an extra copy of the α-synuclein gene, which predisposes them to Parkinson’s. These cells were converted to stem cells, and the stem cells converted to neurons. Treating them with one of the drugs that came through the screen reduced α-synuclein expression, lowered the mortality of the cells, and kept their energy metabolism under better control.
  </p>
 </blockquote>
 <p>
  The researchers urge people not to rush and get prescriptions for these drugs. They’re currently not FDA-approved to treat Parkinson’s and the drugs can actually increase cardiovascular disease.
 </p>
</section>
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 Photo credit:
 <a href="https://www.nih.gov/news-events/news-releases/researchers-examine-how-parkinsons-disease-alters-brain-activity-over-time">
  David Vaillancourt / National Institutes of Health
 </a>
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Ana Aceves

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