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Reptiles and birds : a popular account of the various orders; with a description of the habits and economy of the most interesting / by Louis Figuier ; edited by Parker Gillmore
Also available online.
Reptiles and birds. A popular account of the various orders; with a description of the habits and economy of the most interesting. / From the French of Louis Figuier. New edition, revised by Parker Gillmore
Reptiles that live near and feed upon amphibians in the tropics may be spreading the deadly amphibian disease Chytridiomycosis (caused by the chytrid fungus Batrachochytrium dedrobatidis), holding and transporting reservoirs of the fungus on their skin.
The post Reptiles may be spreading deadly amphibian disease in the tropics appeared first on Smithsonian Insider.
Spine title: Report on the reptiles of Massachusetts.
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Reptiles, amphibia, fishes and lower chordata, by Richard Lydekker, J. T. Cunningham, G. A. Boulenger, and J. A. Thomson. With four plates in colour, thirty-three in monotone, a map and many text figures
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Digitization and preparation of these materials for online access has been funded through generous support from the Arcadia Fund.
"The Mind-soothing Address".
Requirement of low oxidation-reduction potential for photosynthesis in a blue-green alga (Phormidium sp.)
Several years ago, an art curator in search of a work by an African-American artist visited the gallery of a leading historically black university. He was anguished by what he discovered. "I saw major works by Romare Bearden, Wifredo Lam, Edmonia Lewis, William H. Johnson, and others stacked cheek to jowl," without benefit of a climate-controlled environment or proper storage. The painting he sought was punctured and torn.
That experience stayed with Jock Reynolds, director of the Yale University Art Gallery, and inspired him and Richard J. Powell, chair of the Department of Art and Art History at Duke University, and a host of their colleagues to launch a project to conserve the art collections at black colleges.
The ambitious undertaking involved the collaboration of six universities, several museums, corporate donors, art experts and student interns, and significant hands-on work at the Williamstown Art Conservation Center in Massachusetts. After five years, the participants had repaired and preserved some 1,400 artworks and assembled an eye-opening touring show of 260 of them titled "To Conserve a Legacy: American Art from Historically Black Colleges and Universities."
Now on view at the Clark Atlanta University Art Galleries and the High Museum of Art in Atlanta through September 24, the exhibition spans more than a hundred years, from mid-19th-century works such as Edmonia Lewis' neoclassical sculptures and Robert Duncanson's pastoral landscapes to more contemporary pieces like the 1960s-era color-drenched Jazz Musician by James Weeks (shown above) and the brilliantly hued Spring Flowers Near Jefferson Memorial, a mosaic-like canvas by Alma Woodsey Thomas.
Such a feast for the eyes should stimulate interest in the artistic treasures at black colleges and encourage support of conservation, Powell said. "Ultimately, we hope we have planted a seed about the importance of preserving one's legacy."
By Marian Smith Holmes
Last May, a Smithsonian researcher traveled to a farming village in Argentina, where documentary filmmaker Jorge Prelorán filmed a movie four decades ago. The researcher brought with him a copy of the film, the only one in existence. No one from the village had ever seen the film, Valle Fértil, but 500 people showed up to its screening at a local gymnasium. Among the crowd were two people who appeared in the film, as well as the children and grandchildren of other people on screen. Chris Moore, the researcher, says many of them had tears in their eyes.
Behind the mission to reintroduce the world to Prelorán's work is the team at the Human Studies Film Archives, part of the anthropology department at the Smithsonian’s National Museum of Natural History. The Archives launched an online hub for its Prelorán project, which has involved preserving his films and screening them around the world. Following the event in Argentina and screenings in Chile last month, Prelorán’s restored Valle Fértil shows for the first time in the United States on December 4 at the Society for Visual Anthropology Film Festival in Washington, D.C. An exclusive clip from the preserved film appears above.
Before his death in 2009, the Argentine-American filmmaker made more than 60 films, some of which have only one remaining print. Once a film student at U.C.L.A., Prelorán took to documentary film in the early 1960s, at a time of renewed interest in the medium, thanks to the cheaper, lighter-weight equipment. “This was a period when there was a lot of excitement about the possibility of anthropological films being used for teaching,” says archives director Jake Homiak. “Prelorán’s films are nested in that same area.”Argentine-American documentary filmmaker Jorge Prelorán donated his life's work to the Smithsonian's Human Studies Film Archives in 2005. (Photo by Lorenzo Kelly. Human Studies Film Archives, Smithsonian Institution ) Prelorán left Argentina and eventually settled in Los Angeles. He's shown here during the filming of Casabindo in 1977. (Photo by Lorenzo Kelly. Human Studies Film Archives, Smithsonian Institution )
At first, the filmmaker took on science subjects, but it wasn’t long before he shifted to more humanistic stories. “He fell in love with the cultures, the people who lived in very remote areas of Argentina,” says his wife, Mabel Prelorán, who lives in Los Angeles. “To him, it was a revelation to see the struggles of these people, the suffering.”
Life as a filmmaker in Argentina wasn't easy. Following the disapeparance of some friends and a family member, Prelorán and his wife decided to leave Argentina. But fearing the military regime, the filmmaker did not want to travel with some of his more political work, and so he asked friends to hide the film reels. The friends buried the reels in a garden, where they remained for a long time until Prelorán's sister-in-law eventually brought them to the filmmaker in Los Angles. “Jorge put in those films all his life,” his wife says.
Unlike other documentary filmmakers, Prelorán didn’t treat his subjects as foreign. In one of the most celebrated documentary films of all time, Nanook of the North, for example, filmmaker Robert Flaherty depicted his Inuit subject as an exotic character to be observed. Prelorán, on the other hand, spent time getting to know his subjects. “He kept in contact with people until the people died. They became part of our extended family,” Mabel Prelorán says about her husband’s subjects.Unlike other anthropological filmmakers, Jorge Prelorán spent time getting to know his subjects. Here, a still from Chucalezna (1968). (Human Studies Film Archives, Smithsonian Institution)
The idea to donate his life work’s to the Smithsonian came around 2005, when Prelorán heard that his film collector friend had recently donated. So he contacted the Smithsonian, and archivist Karma Foley traveled to Los Angeles to collect the materials. Foley spent several days organizing the prints, which the filmmaker had kept in zip-lock bags in his finished attic. At the time, Prelorán was undergoing chemotherapy. “He was being very reflective, thinking about his legacy,” Foley says.
Once the materials arrived at the Archives, archivist Pam Wintle says, “We immediately launched a project to begin to preserve the film.” That effort involved doing photochemical restoration and adding English subtitles.
“Very few people actually got to see his films,” says Smithsonian Fellow Chris Moore, who screened the films in Argentina and Chile. “People generally don’t know very much about who he is, but this is a good first step.”The Human Studies Film Archives has more than 60 of Prelorán's films and is doing preservation work. This image was taken during the filming of Hermogenes Cayo (1970). (Photo by Lorenzo Kelly. Human Studies Film Archives, Smithsonian Institution ) Here, a subject from one of Jorge Prelorán's films, Damacio Caitruz (1995). (Photo by Lorenzo Kelly. Human Studies Film Archives, Smithsonian Institution)
In 2010, bottlenose dolphins (Tursiops truncatus) started washing up on the shores of Mississippi, Louisiana and Alabama. Many were already dead, and some died soon after. This mysterious die-off continued through 2014, reaching numbers never before seen in the Gulf of Mexico.
This week researchers confirmed suspicions that oil from the 2010 BP Spill had contributed to these dolphin deaths. Examining stranded dolphins over the course of two years, the team found lesions linked to petroleum exposure. "No feasible alternatives remain," NOAA's Stephanie Venn-Waston said in a press conference Wednesday.
Occasional cases of dolphins washing ashore and getting stranded are normal. Usually this happens with sick or injured animals. But, the Gulf coast has seen a huge spike in dolphin strandings — 1300 since 2010 — and over 90 percent of the animals have died.Louisiana Department of Wildlife and Fisheries (Louisiana Department of Wildlife and Fisheries)
From June 2010 to December 2012, NOAA researchers collected tissue samples from deceased dolphins in the Gulf. A bit of forensic invetigating revealed that the animals had lesions on their adrendal glands and lungs. Exposure to petroleum compounds causes these types of lesions, and the researchers posit that the petroleum that caused these lesions came from the Deepwater Horizon rig explosion. The dolphins likely inhaled fumes from the surface.
One in five of the dolphins examined had lung lesions caused by bacteria pneumonia. "These dolphins had some of the most severe lung lesions I have seen in the over 13 years that I have been examining dead dolphin tissues from throughout the United States,” Kathleen Colegrove, a researcher at the University of Illinois and the study’s lead veterinary pathologist, said in the press release.
The findings, published May 20 in the journal PLOS ONE, back up a 2011 health assessment of bottlenose dolphins living in Barataria Bay in Louisiana that showed high rates of lung diseases, adrenal problems and general bad health. During the 2010 oil washed into the bay, and the area saw a significan dolphin die-off in 2010 and 2011.
BP spokesperson Geoff Morrell released a statement to several news outlets (Nature, Newsweek, PBS News Hour, among others) denying any connection between the dolphin deaths and their Macondo Well spill: "The data we have seen thus far, including the new study from NOAA, do not show that oil from the Deepwater Horizon accident caused an increase in dolphin mortality."
If, as the research suggests, dolphins did die from the effects of the spill, it's still not clear what additional effects of the spill will ooze to the surface for dolphins in the long term.
Biologists and nanotechnology researchers at Rice University have been working for years on a U.S. Navy-funded project to create a material that can visually adapt to its surroundings in real-time. The goal is to allow ships, vehicles and eventually soldiers to become invisible—or nearly invisible—just like some species of squid and other cephalopods.
With squid skin as their model, the scientists developed a flexible, high-resolution, low-power display that could realistically mimic its environment. The new display technology actually makes individual pixels (the tiny colored dots that make up the image on your television and smartphone) invisible to the human eye. Using aluminum nanorods of precise lengths and spacing, the researchers found they could create vivid dots of various colors that are 40 times smaller than the pixels found in today’s TVs.
How it Works
In a study recently published in the early edition of the Proceedings of the National Academy of Sciences (PNAS), the authors illustrate how they used a technique called electron-beam deposition to create arrays of nanorods and five-micron-square pixels—roughly the size of a plant or mold spore—that produce bright colors without the use of dyes, which can fade over time. The color of each of these tiny pixels can be finely tuned by varying either the distances between the rods in the arrays or the lengths of individual rods.
The color of the pixel is produced when light hits the nanorods and scatters at specific wavelengths. By varying the arrangement and length of the surrounding nanorods, the team is able to precisely control how the light bounces around, narrowing the spectrum of light and, in effect, adjusting the visible light each pixel gives off. The pixels the team created are also plasmonic, meaning they get brighter and dimmer depending on the surrounding light, much like the colors in stained glass. This could be useful in creating lower-power displays in consumer devices, which should also be less stressful on the eyes.
Because the technology relies mostly on aluminum, which is inexpensive and easy to work with, these types of displays shouldn’t be prohibitively expensive or exceedingly difficult to manufacture.
Room for Improvement
Stephan Link, an associate professor of chemistry at Rice University and the lead researcher on the PNAS study, says the team didn’t set out to solve any fundamental problems with existing display technology, but to work toward smaller pixels for use in a wearable, low-power material that is thin and responsive to ambient light.
“Now that we have these nice colors,” he says in an email, “we’re thinking of all the ways we can improve them, and how we can work toward the nano squid skin that is the ultimate goal of this collaboration.”
According to Link, one way to improve the technology would be to partner with experts in the commercial display industry. While the technology for making the pixels is very different, the team expects many of the other display components, like the liquid crystals that determine a display’s refresh rate and pixel response time, will remain the same or similar to those used today.
To make a flexible display, the researchers may try to build the pixels like scales, so that the underlying material can bend, but the liquid crystals and aluminum nano-array can remain flat. But to get to that point, the team may need help.
“It seems kind of funny to say it, but one major hurdle is to scale down the size of the liquid crystal part of our displays,” writes Link. “You see very tiny LCD screens all the time in technology, but we don’t have the fancy industrial machines capable of making those with such high precision and reproducibility, so that’s a major hurdle on our part.”
Another potential hurdle is to replicate the vast array of colors possible in today’s high-end displays. While the researchers aren’t quite there yet, Link seems confident that their technology is up to the task.
“The great thing about color is that there are two ways to make it,” says Link. “For example, the color yellow: The wavelength of light that looks yellow is 570 nanometers, and we could make a pixel that has a nice sharp peak at 570 nm and give you yellow that way. Or, we can make yellow by placing a red pixel and a green pixel next to each other, like what is done in current RGB displays. For an active display, RGB mixing is the way to do it efficiently, but for permanent displays, we have both options.”
RGB mixing has visible drawbacks in existing displays, because the pixels are often visible to the naked eye. But with this technology, you’d need a microscope to see them and to discern which color-creating method is being used.
Applying the Finding to Consumer Technology
The ability to precisely create and manipulate the tiny nano-scale rods plays a large role in the team’s breakthrough. Getting the length or spacing of these tiny rods even slightly off would affect the color output of the completed display. So, scaling manufacturing up to mass-produce these types of displays could also pose a problem—at least at first. Link is hopeful though, pointing to two existing manufacturing technologies that could be used to build these kinds of displays—UV lithography, which uses high-energy light to produce tiny structures, and nanoimprint lithography, which uses stamps and pressure (much like the way the digits on a license plate are embossed, but on a microscopic scale).
“Other than finding the right method so we can pattern larger areas,” says Link, “the rest of the manufacturing process is actually pretty straightforward.”
Link didn’t want to guess as to when we might see these nano-scale pixels used in commercial displays and devices. At this point, he and his fellow researchers are still focused on refining the technology toward their goal of squid-like camouflage. A collaboration with commercial display makers could help the team get closer to that goal though while also leading to new kinds of displays for consumer devices.
Perhaps Link's group at Rice should team up with researchers at MIT, who are also working on replicating the properties of cephalopod skin. The scientists and engineers there recently demonstrated a material that can mimic not only color, but also texture. This will be an important feature for the military's goal of making vehicles invisible. A flexible display could, for example, make a tank look like rocks or rubble from afar. But if its sides are still smooth and flat, it will still stand out on closer inspection.
Sunflowers may be beautiful but there's something that's also a little bit creepy about them. During the growing season, the young sunflowers rotate their bright yellow heads during the day to track the sun's movement across the sky. They reset overnight, swinging their face back to the east. Now, a new study published in the journal Science, suggests how and why the big bloomers do it.
To figure out why the sunflowers rotate, a team of researchers from the University of California, Davis looked at whether the flowers were following the sun or following an internal cue from a circadian rhythm. JoAnna Klein at The New York Times reports that the researchers tested this by placing sunflowers in an indoor room with lights designed to mimic the sun’s daily path. During a 24-hour cycle, they behaved normally. But once they were put on a 30-hour cycle, their rhythm was off. This means the plants likely follow an internal circadian rhythm.
“It’s the first example of a plant’s clock modulating growth in a natural environment, and having real repercussions for the plant,” UC Davis plant biologist and senior author of the study Stacey Harmer says in a press release.
But how do they turn their heads? The researchers found that during the day, genes click on causing the east-facing half of the stem to grow. The lengthening stem causes the flower head to slowly bend to the west during the day. At night, genes causing the west side of the stem to grow activate, causing the head to flip back to the east, explains Klein.
To tackle the question of why, the team studied if there were any benefits to facing the sun all the time—a trait common among older sunflowers. reports Emily Benson reports for New Scientist that the researchers studied sunflowers in pots, restraining some so they could not move their heads and rotating others so they could not follow the sun. What they found is the leaves of those sunflowers were 10 percent smaller than their freewheeling kin. Moving their head, they conclude gives the plants a boost in efficiency.
When the plant fully matures, it faces permanently east, which benefits the aging bloom as well. The researchers found that east-facing flowers heat up more quickly in the morning, attracting five times as many pollinators as west-facing blooms. This find supports previous studies, which suggest that bees and other pollinators prefer warmer flowers in the morning.
“I’m continually astonished at how sophisticated plants are,” Harmer tells Benson. “They’re really masters of coping with the environment.”
The Black Death, an outbreak of bubonic plague that devastated Europe and Asia between 1346 and 1353, is considered one of the greatest cataclysms of all time. The disease, caused by the bacteria Yersinia pestis and transmitted by fleas, wiped out half the population according to contemporary accounts. The famous Italian poet Francesco Petrarch told a friend that he did not think people in the future would even believe their suffering. ‘O happy posterity,” he wrote after watching half the city of Florence die, “who will not experience such abysmal woe and will look upon our testimony as a fable.’
As it turns out, Petrarch was partially right. No one disputes that the Black Death happened or that it was a society-reordering disaster. But, as Sarah Kaplan reports in The Washington Post, researchers haven’t had much to go on to confirm the claims that a quarter to half of Europe’s population perished because of the plague. Compared to modern plagues, like the Spanish flu in the early 20th century, which killed about 3 percent of the world’s population, the number killed by the Black Death seemed high.
That’s one reason archaeologist Carenza Lewis of the University of Lincoln decided to dig a little deeper. She excavated 2,000 one-meter-square pits in 55 rural settlements occupied before and after the plague across eastern Britain, looking for the concentration of pottery shards, broken bits of everyday pottery.
“Under every village, every community, there is a huge reservoir of archaeological evidence just sitting there,” she tells Kaplan. “Evidence of these life-shattering events that people like us would have lived through — or not.”
Her findings, which will appear in Antiquity Journal, show that in many places the pot shards are plentiful in pre-plague layers, while in the time after the disease they seriously diminish. According to Maev Kennedy at The Guardian, the overall decline was about 44.7 percent. The devastation was not equal, though, with places in England like Norfolk showing a 65 percent decline and Gaywood and Paston showing up to 85 percent drops. Kennedy points out that the numbers are likely conservative since villages that were totally wiped out or abandoned because of the Black Death were not sampled.
Lewis tells Kennedy it was devastation on “an eye-watering scale” and that a population boom in later centuries masked the true toll. She points to villages like Great Shelford in Cambridgeshire. Before the plague the village stretched two-thirds of a mile along a main street. After the plague, the survivors all fit into a row of houses next to the church. Emily Reynolds at Wired UK writes that the pottery evidence shows that many of the towns examined remained 35 to 55 percent below pre-Black Death population levels well into the 16th century.
Luckily for us, the strain of Yersinia pestis that caused the Black Death was a novel mutation of the bacteria, and has since disappeared. But Lewis thinks the world should still be cautious. In a line from her upcoming paper that Kennedy shares, Lewis writes, “This disease is still endemic in parts of today’s world, and could once again become a major killer, should resistance to the antibiotics now used to treat it spread amongst tomorrow’s bacteriological descendants of the fourteenth-century Yersinia pestis. We have been warned.”