'Microbial Pompeii' Found on 1,000-Year-Old Teeth

A "microbial Pompeii" has been found on the teeth of 1,000-year-old human skeletons. Just as volcanic ash entombed the citizens of the ancient Roman city, dental plaque preserved bacteria and food particles on the skeletons' teeth.

Researchers analyzed dental plaque from skeletons in a medieval cemetery in Germany, and found that the mouths of these aged humans were home to many of the same bacterial invaders that cause gum disease in the mouths of modern humans.

"One thing that is clear about the population we studied is that they didn't brush their teeth very often, if at all," said study leader Christina Warinner, an anthropologist at the University of Zurich in Switzerland and the University of Oklahoma in Norman.

The discovery of these bacteria also revealed clues to the dental hygiene and diets of these centuries-old humans, according to the study detailed today (Feb. 24) in the journal Nature Genetics.

Plaque is a dentist's worst enemy, but it turns out to be a great time capsule for preserving the bacteria (or "microbiome") and bits of food on the teeth of humans long after they die. The sticky bacteria on teeth trapped particles of food and other debris, and over time, the calcium phosphate in saliva — the same mineral found in bones and teeth — caused the plaque to calcify into tartar.

"We knew that calculus preserved microscopic particles of food and other debris but the level of preservation of biomolecules is remarkable — a microbiome entombed and preserved in a mineral matrix, a microbial Pompeii," another study researcher, Matthew Collins from the University of York, in England, said in a statement.

With their new study, Warinner and her colleagues are the first to sequence the DNA in ancient dental tartar, using a rapid method known as "shotgun sequencing." The team reconstructed the genome of a major bacterial pathogen and recovered some of the first evidence of food molecules from ancient dental plaque.

The DNA in food found in the plaque matched pigs, sheep, bread wheat and vegetables such as cabbage. The researchers also found starch granules that matched cereals and the pea/bean family.

"Amazingly, it's much the same thing you would find at a German restaurant today," Warinner said.

The skeletons had many years' or decades' worth of plaque built up on their teeth, and many of them showed signs of gum disease and tooth decay. While a few individuals had surprisingly healthy teeth, most of the older adults had lost most or all of their teeth due to wearing, decay or dental disease.

The microbe species found in the ancient plaque were remarkably similar to ones found in modern mouths, the researchers said. Gum disease is most often caused by the species Porphyromonas gingivalis, Tannerella forsythia,Treponema denticola and Filifactor alocis, and these microbes were all present on the teeth of the skeletons with dental disease.

Read more at Discovery News

New MERS Virus Widespread in Camels

The majority of camels in Saudi Arabia have been infected with Middle East Respiratory Syndrome (MERS) virus, and the virus has been circulating among the animals there for at least 20 years, a new study suggests.

Researchers tested blood, nasal and rectal samples from dromedary (one hump) camels throughout Saudi Arabia, as well as archived blood samples from camels in the region that were collected as far back as 1992. MERS first appeared in people in September 2012, and since then, 182 people have been infected, most in Saudi Arabia. Seventy-nine people have died from the infection.

The first person known to have MERS was a Saudi Arabian man who owned four pet camels.

The new research found that 74 percent of camels had antibodies against the MERS virus, indicating that they had been infected with MERS virus or a very similar virus in the past. Antibodies were more common in adult camels than young camels: 95 percent of camels older than age 2 had antibodies against the virus, compared to 55 percent of camels younger than 2.

In contrast, younger camels were more likely to have active virus (35 percent of young camels had active virus in their nasal samples, compared to 15 percent of adult camels).

These finding suggest that, for camels, MERS infection "typically occurs in early life, and that if people get the virus from camels, the most likely source is young camels," study researcher Dr. W. Ian Lipkin of Columbia University, New York, said in a statement.

The archived blood samples also contained MERS antibodies, suggesting the MERS or a similar virus has been circulating in camels for at least two decades.

Previously, the researchers found that camels had antibodies against the MERS virus, and that some were infected with active virus. The new study is the first to perform a countrywide survey of camels in Saudi Arabia.

However, the new study does not prove that humans caught the virus from camels, and more studies are needed to rule out other possibilities. For example, it could be that another animal infects both humans and camels. The MERS virus has also been found in bats.

Read more at Discovery News

Advanced Exoplanet Hunter Images Alien Worlds

A planet-hunting project is snapping pictures of alien worlds and other objects orbiting nearby stars in an effort to give scientists a better understanding of these intriguing exoplanets.

Project 1640 is designed to probe the atmospheres of exoplanets to create new, low-resolution images of the planets and their stars. By understanding the atmosphere of the planets and the composition of the stars, scientists working with the project could potentially learn more about how they formed.

Scientists working with Project 1640 — an imaging system at the Palomar Observatory in California — are using the specialized system to survey about 200 stars looking for a range of planets and other objects, project scientist Ben Oppenheimer said at the American Museum of Natural History event on Feb. 5. According to AMNH officials, Project 1640 is "the most advanced and highest contrast imaging system in the world."

"The planets of our own solar system, of course, are planets in and of themselves and in order to understand them — and indeed this planet — I think we need to study other planets," Oppenheimer said. "If you just look at the planets of our own solar system, they're really complicated."

The project is designed to help space scientists get a better sense of the diversity of planets that exist in the universe. Scientists are also looking for mysterious cosmic objects known as brown dwarfs that are too large to be considered a planet, but too small to produce fusion in their cores.

Different chemicals, like carbon dioxide, absorb light differently, allowing scientists working with Project 1640 to take measurements and see where various signatures fall on the spectra.

Oppenheimer and his colleagues using Project 1640 have already peered into the atmospheres of four cloud-covered alien planets around the star HR 8799, 127 light-years from Earth. All four of the planets are more massive than Jupiter and display some odd characteristics.

"These warm, red planets are unlike any other known object in our universe," Oppenheimer said in a statement announcing the discovery in 2013. "All four planets have different spectra, and all four are peculiar. The theorists have a lot of work to do now."

Read more at Discovery News

200-Year-Old Douche Found Under New York's City Hall

While sifting through a 19th-century trash heap buried below Manhattan's City Hall Park, archaeologists found a dirt-caked tube that was finely carved out of bone and had a perforated, threaded screw cap. Only recently did they discover it was actually a vaginal syringe used for douching.

The feminine hygiene device seems to have been tossed out with the refuse of a pretty good party around the time City Hall was being built 200 years ago. Archaeologists say the syringe was unearthed among alcohol bottles, smoking pipes, fine pottery and the bones of sheep, cows, fish and even turtles — then a delicacy — that were likely served for dinner.

"We think the trash deposit feature was from a single event, possibly a celebratory event," said Alyssa Loorya, who heads the Brooklyn-based Chrysalis Archaeological Consultants. She explained the pile didn't have the characteristic layers that would build up over time in a continuously used dump.

The garbage pile was uncovered during excavations in 2010 as part of a project to rehabilitate City Hall, Loorya told Live Science. But the syringe wasn't identified until Chrysalis archaeologist Lisa Geiger, who is a graduate student at Hunter College, made the connection while she was volunteering as a guide at Philadelphia's Mutter Museum.

The museum houses all sorts of medical oddities, and while looking through the back collections, Geiger said she came across vaginal syringes that were the same size and shape as the object found at City Hall.

The device would have been used to irrigate the vagina with different solutions and tonics to treat venereal disease, prevent pregnancy and maintain good hygiene. (Douching is generally discouraged today as research has shown the practice can disturb the natural bacterial ecosystem of the vagina.)

These syringes weren't uncommon, but discussing feminine hygiene openly at the time was taboo. To research 19th-century douching, Geiger turned to historical ads and instructional booklets, which were becoming more prevalent as consumer trade grew and women took charge of family health care.

"There are these advertisements that kind of use creative language to dance around the use of these things," Geiger told Live Science. "It's not written about so overtly in the record, so the physical object in this case gave us an avenue to look at how women conceived of themselves and how they conceived of their hygiene."

Read more at Discovery News

Neanderthals Faced Extinction Before Humans Appeared

Western Europe may have undergone a population crisis during a cold stretch of the Neanderthal era, a new study of mitochondrial DNA sequences suggests.

"The fact that Neanderthals in Western Europe were nearly extinct, but then recovered long before they came into contact with modern humans came as a complete surprise to us," study co-author Love Dalén, associate professor at the Swedish Museum of Natural History in Stockholm, told Phys.org.

"This indicates that the Neanderthals may have been more sensitive to the dramatic climate changes that took place in the last Ice Age than was previously thought."

By analyzing the amount of genetic variation in the DNA from 13 Neanderthals, the scientists pieced together the puzzle of a demographic history. The DNA of Neanderthals from more than 50,000 years ago showed a high degree of genetic variation, in contrast to the DNA of those from less than 50,000 years ago. That group showed much less genetic variation.

Until now, the Neanderthal population was assumed to be stable until modern humans began showing up. Extinction was avoided when Neanderthals from surrounding areas repopulated the region. But the new research suggests that Neanderthals may have been more susceptible to cold than previously thought.

"At the very least, this tells us that without the aid of material culture or technology, there is a limit to our biological adaptation," co-author Rolf Quam of the University of Binghamton said.

Read more at Discovery News

Rare, Polio-Like Disease Found in Calif. Children

A rare, polio-like syndrome that has no known cure has emerged in a small number of children in California, U.S. researchers said.

Five cases of sudden onset paralysis were described by Stanford University experts at the American Academy of Neurology annual meeting in Philadelphia.

"Although poliovirus has been eradicated from most of the globe, other viruses can also injure the spine, leading to a polio-like syndrome," said Stanford neurologist and lead author of the case reports, Keith Van Haren.

"In the past decade, newly identified strains of enterovirus have been linked to polio-like outbreaks among children in Asia and Australia," he said in a statement.

"These five new cases highlight the possibility of an emerging infectious polio-like syndrome in California."

Polio has been largely wiped out across the globe, thanks to the introduction of an effective vaccine in the mid 1950s.

However, outbreaks of the highly contagious disease continue in parts of the world, including Pakistan, Nigeria and Afghanistan.

The California children tested negative for polio, and all had been vaccinated.

The patients showed similar symptoms, such as sudden loss of movement in one or more of their limbs, resulting in paralysis usually within two days.

Three of the five youths had respiratory illness before their symptoms began.

Two have tested positive for enterovirus-68, a rare virus that has been previously associated with polio-like symptoms.

Read more at Discovery News

Peru's Manu National Park sets new biodiversity record

Peru's treasured Manu National Park is the world's top biodiversity hotspot for reptiles and amphibians, according to a new survey published last week by biologists from the University of California, Berkeley, Southern Illinois University in Carbondale (SIU-Carbondale) and Illinois Wesleyan University.

The park, which encompasses lowland Amazonian rain forest, high-altitude cloud forest and Andean grassland east of Cuzco, is well known for its huge variety of bird life, which attracts ecotourists from around the globe. More than 1,000 species of birds, about 10 percent of the world's bird species; more than 1,200 species of butterflies; and now 287 reptiles and amphibians have been recorded in the park.

"For reptiles and amphibians, Manu and its buffer zone now stands out as the most diverse protected area anywhere," said study coauthor Rudolf von May, a post-doctoral researcher in UC Berkeley's Museum of Vertebrate Zoology.

Despite the park's abundant and diverse animal life, von May said, not all is well in the preserve. The devastating chytrid fungus has caused a decline in the number of frogs there, as it has elsewhere around the world, while deforestation for subsistence living, gold mining and oil and gas drilling are encroaching on the buffer zone around the park.

"All of this is threatening the biodiversity in the park and the native peoples who live in settlements in the park," von May said. At least four Amazonian tribes and a nomadic group of hunter-gatherers known as Mashco-Piro live within the confines of Manu National Park and its buffer zone.

Von May, a native of Peru, and coauthor Alessandro Catenazzi, an assistant professor of zoology at SIU-Carbondale, have spent more than 15 years each scouring the park and its surrounding areas for frogs, toads, salamanders and caecilians -- all amphibians -- as well as for reptiles such as snakes, lizards, turtles and caimans. The field work in the park and its buffer zone, augmented by other, more limited surveys published previously, allowed the team to compile a list of 155 amphibian and 132 reptile species, including a handful of species new to science. Taxonomist and coauthor Edgar Lehr, assistant professor of biology at Illinois Wesleyan University, collaborates frequently with von May and Catenazzi on frog taxonomy and studies of amphibian declines and conservation.

Record-breaking biodiversity

The researchers listed the 287 species of reptiles and amphibians in the most recent issue of the journal Biota Neotropica. The previous record for the most diverse protected area for reptiles and amphibians was in Yasuní National Park in Ecuador, which hosts 150 amphibian and 121 reptile species, according to a 2010 study.

"There is no place like Manu where we can preserve such an exceptionally large amount of biodiversity, as well as the evolutionary processes that contribute to maintain and promote biodiversity," said Catenazzi, a former postdoctoral researcher in UC Berkeley's Department of Integrative Biology. "It is our responsibility to make sure this biological legacy is passed on to the next generations."

To assemble the list, the team surveyed multiple elevations and examined hundreds of museum specimens collected at dozens of locations in Manu National Park and its buffer zone. Analysis of DNA sequences and frog calls allowed the team to identify additional species.

World Heritage Site

While the high species diversity can be partially attributed to the large area and steep topographic variation within Manu National Park, the finding is noteworthy, von May said. He and his colleagues estimate that the park represents only 0.01 percent of the planet's land area, but houses 2.2 percent of all amphibians and 1.5 percent of all reptiles known worldwide.

Since its creation 41 years ago, Manu National Park has become recognized as globally irreplaceable: it was designated a UNESCO Biosphere Preserve in 1977 and a World Heritage Site in 1987. Herpetologists -- experts in reptiles and amphibians -- first surveyed the region in the 1970s, primarily along the road that connects the city of Cuzco to villages in the cloud forests of the Kosñipata Valley. Starting in the '80s, research was broadened to include remote lowland rainforest locations, such as Cocha Cashu Biological Station, inside the park. Subsequent expeditions have continued to reveal new species of amphibians and reptiles, especially in the cloud forest and high-Andean grasslands, which are rich in endemic species, Catenazzi said. One of the most recent discoveries was the glass frog Centrolene sabini, the world's 7,000th known amphibian species.

Read more at Science Daily

How Snails, Clams Are the Ultimate Survivors

The most catastrophic mass extinction in the history of Earth had little effect on the lifestyles of the lowliest of beasts living in the “benthic” (bottom-dwelling) muck on the sea floor, according to a new study. This could explain the puzzling fact that even after the worst extinction event of all time, very few new groups of benthic animals -- like snails and clams -- sprung from the wreckage.

Despite the fact that 96 percent of marine species perished in the end-Permian extinctions, some 252 million years ago, only one of the 25 benthic lifestyles that then existed actually disappeared when life struggled on into what's called the Triassic period. That made it harder for new groups of benthic animals to evolve in the aftermath, said William Foster and Richard Twitchett of Plymouth University in the U.K. Their study appears in the Feb. 23 issue of the journal Nature Geoscience.

Put in theatrical terms, it's as if the roles in a play survived despite many changes of actors, making it very hard for the overall plot to change much.

“Globally, the Early Triassic benthic ecosystem functioned much like a ship manned by a skeleton crew. Each post was occupied, but by only a few individual taxa (groups),” Foster said.

That skeleton crew appeared to be enough, however, to keep intact the lifestyles that have defined benthic animals ever since.

To come to that conclusion, Foster and Twichett had the daunting task of sorting through the worldwide benthic fossil record from that pivotal time in Earth's history.

Previous studies have looked at the groups that went extinct, of course, as well as how new lifestyles “went viral” and spread through the world, but this is the first to look at the greatest extinction solely terms of animal roles -- or the “ecospace” -- that animals filled.

“We sort of ignored (the animals') names for this study,” explained Foster. One advantage of this approach, he said, is that when the fossil record lacks evidence of a particular animal for a period of time, you can sometimes follow the lifestyle to fill in the blanks.

“The ecospace occupied by a marine organism is characterized by three ecological variables: mobility, feeding mechanism and living location,” explained Martin Aberhan of the Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity in Germany.

None of this means to suggest that the extinction event, which was accompanied by a severe bout of global warming, went entirely unnoticed by sea-floor inhabitants.

Read more at Discovery News

11,000-Year-Old Settlement Found Under Baltic Sea

Evidence of a Stone-Age settlement that may have been swallowed whole by the Baltic Sea has resurfaced near Sweden, revealing a collection of well preserved artifacts left by nomads some 11,000 years ago.

Dubbed by the local press “Sweden's Atlantis” after the fabled island which according to Greek philosopher Plato sank around 9600 B.C. in the Atlantic Ocean, the newly discovered site was in fact some sort of a dump in which nomadic Swedes discarded objects, according to a report by the Swedish daily The Local.

Buried 52 feet below the surface at Hanö, a sandy bay off the coast of Skane County in Sweden, the items include wood pieces, flint tools, animal horns, ropes, a harpoon carving made from an animal bone and the bones of an aurochs and an ancient cattle which became extinct in the early 1600s.

"There's wood and antlers and other implements that were thrown in there," project leader Björn Nilsson, archaeology professor at Södertörn University, told the Local.

Amazingly, the artifacts have been perfectly preserved because of the abundant oxygen-consuming“gyttja” -- a black, gel-like sediment which is formed when peat begins to decay.

"Around 11,000 years ago there was a build up in the area, a lagoon or sorts ... and all the tree and bone pieces are preserved in it. If the settlement was on dry land we would only have the stone-based things, nothing organic," Nilsson said.

Read more at Discovery News

Oldest Rock Speck Zeros In On Earth's Cooling Date

The oldest remaining grain of early Earth's original solid rock crust has now been confirmed to be a 4.374-billion-year-old old zircon crystal from Jack Hills, Australia.

That age should settle a scientific debate over the accuracy of that mineral's internal clock, and cuts the time from when Earth was hit by a Mars-sized body (which led to the formation of the Moon) and the cooling and creation of Earth's first solid crust from 600 million years to 100 million years.

“This, I believe, is the oldest zircon that's ever been dated on Earth,” said John Valley, of the University of Wisconsin in Madison. He and his colleagues have published their findings in the Feb. 23 issue of the journal Nature Geoscience.

Previous dating of the ancient Jack Hills zircons about ten years ago had arrived at ages of about 4.4 billion years, Valley explained. But there were doubts about whether some of the atomic elements used for the dating had moved about in the crystals and thrown off the age by a few hundred million years.

“Whether a grain is 4.3 or 4.4 billion years old, and whether this reflects a primary age, is not a trivial matter,” explained Sam Bowring of the Massachusetts Institute of Technology.

“In the context of the 4.4- to 4.5-billion-year age of the Earth, a difference in age of 0.1 or 0.2 billion years (100 or 200 million years) is enormous in terms of modeling the geochemical evolution of Earth and the formation and recycling of the first continental crust.”

The element in question is an isotope of lead, which is created by the radioactive decay of uranium in zircons.

The age of a grain is figured by measuring the amounts of the parent uranium isotopes compared to the daughter lead isotopes. This is only accurate if no uranium or lead gets into or escapes the zircon.

Researchers were concerned that the very process of uranium decaying -- which fires out a high-speed alpha particle -- might have kicked around lead atoms in the zircons and messed things up.

“If the lead leaves, it can be concentrated somewhere else,” said Valley. “The apparent age where it goes will appear older and where it has left will appear younger. What we've done is solve the lead mobility problem.”

They did it by laboriously counting and mapping clusters of lead atoms in the zircon using what's called atom-probe tomography.

“It's astonishing to be able to do this,” said Valley, “literally counting atoms with an atomic probe.”

Valley and his colleagues found that the lead was indeed getting kicked around, but it wasn't going far enough to throw off the age of the zircon.

“I think it settles it, as far as it's possible,” said Valley.

It also points the way for techniques that can be used to better study zircons from beyond Earth, said Valley. There are, for instance, zircons from meteorites that are older than the Earth -- up to perhaps 4.6 billion years old.

Read more at Discovery News