Social Networks Shape Monkey 'Culture' Too

Of course Twitter and Facebook are all the rage, but the power of social networks didn't start just in the digital age. A new study on squirrel monkeys reported in Current Biology, a Cell Press publication, on June 27 finds that monkeys with the strongest social networks catch on fastest to the latest in foraging crazes. They are monkey trendsters.

The researchers, led by Andrew Whiten of the University of St Andrews, made the discovery by combining social network analysis with more traditional social learning experiments. By bringing the two together, they offer what they say is the first demonstration of how social networks may shape the spread of new cultural techniques. It's an approach they hope to see adopted in studies of other social animals.

"Our study shows that innovations do not just spread randomly in primate groups but, as in humans, are shaped by the monkeys' social networks," Whiten said.

Whiten, along with Nicolas Claidière, Emily Messer, and William Hoppitt, traced the monkeys' social networks by recording which monkeys spent time together in the vicinity of "artificial fruits" that could be manipulated to extract tempting food rewards. Sophisticated statistical analysis of those data revealed the monkeys' social networks, with some individuals situated at the heart of the network and others more on the outside. The researchers rated each of the monkeys on their "centrality," or social status in the network, with the highest ratings going to monkeys with the most connections to other well-connected individuals.

The artificial fruits could be opened in two different ways, either by lifting a little hatch on the front or by pivoting it from side to side. The researchers trained the alpha male in one group of monkeys on the lift technique, while the leader in another group was trained on the pivot method. They then sent them back to their groups and watched to see how those two methods would catch on in the two groups.

More central monkeys with the strongest social ties picked up the new methods more successfully, the researchers found. They were also more likely than peripheral monkeys to learn the method demonstrated by their trained alpha leaders.

Whiten said the squirrel monkeys are a good species for these studies because of their natural inquisitiveness. They also lead rather intense social lives.

The researchers now hope to extend their studies to focus on the squirrel monkeys in different contexts -- while foraging, moving, and resting, for example -- and how those contexts might influence the spread of innovations. They suspect they might even find evidence for different monkey subcultures.

Read more at Science Daily

How Earth Heals Itself After an Earthquake

For the first time, scientists have watched the Earth heal itself after an earthquake.

The process is similar to the body repairing a cut, researchers from China and the United States reported this week in the journal Science. During an earthquake, the ground tears apart along a fault, leaving a jagged series of fractures. After China's devastating magnitude 7.9 Wenchuan earthquake in 2008, fluids filled the fractured fault, like blood gushing into a wound, the team found by drilling into the fault.

Within two years — a blink of the eye in geologic time — the fault was speedily knitting itself back together, closing gaps through a combination of processes. But the gashes occasionally reopened when damaged by shaking from distant earthquakes, the study reports.

No one knows for sure how faults heal, and the observations from the Wenchuan drilling project offer more questions than answers. But the project's long-term monitoring of fractures opening and closing on a fault offers a series of fascinating puzzles for scientists to solve, said Chris Marone, a geophysicist at Penn State University who was not involved in the study.

"These are new observations. Unraveling exactly what's going on here could have serious implications for a lot of really important technical things," Marone said. Models based on the results could impact any place where water flows underground, such as in faults or aquifers or wells, he said.

Rapid response drilling

The Wenchuan project team tracked the healing process through a series of deep boreholes drilled through the fault. The study is part of an ongoing global effort to examine faults immediately after earthquakes, in hopes of checking the results of decades of laboratory experiments and computer modeling.

"We already know there are a lot of reasons real faults may not behave the way we think they do," said Emily Brodsky, a study co-author and geophysicist at the University of California, Santa Cruz. "If we're going to gain some actual new insights or go well beyond where our imaginations went before, we need the real deal," she said.

The Chinese-sponsored Wenchuan earthquake Fault Scientific Drilling project began 178 days after the May 12, 2008, earthquake. The massive temblor killed more than 80,000 people. Five boreholes pierced through the messy fault zone, finding 0.4 inches (1 centimeter) of fresh fault gouge, a type of pulverized rock.

For 18 months, the team monitored the fault's permeability, a measure of how quickly water flows through the rock. Permeability is a stand-in for damage on the fault, Brodsky said — as the fault heals, the area should become less permeable to fluids. The experiment tracked the ebb and flow of fault fluids from tidal forces, the same tugs from the sun and moon that create ocean tides.

The researchers saw a steady decrease in permeability at the boreholes. As the gaps and fractures along the fault zone filled in with new minerals deposited by the fluids, or squeezed shut, the permeability drops, the researchers think.

The overall permeability drop was significantly faster than predicted by laboratory experiments, Brodsky told LiveScience's OurAmazingPlanet. The likely reason is rapid fault healing, but Brodsky said she doesn't have a good explanation for how that happens yet. "I don't know why it's faster," she said. "This sort of begs us to work out the process."

Remote triggering
But they did solve another puzzle: Six short-term jumps in the permeability, random events with no link to local aftershocks or equipment problems. The team eventually realized shaking from big but distant earthquakes broke open healed sections of the fault, Brodsky said. Some of the remote culprits include the March 2011 Japan earthquake and a magnitude-7.8 earthquake in Sumatra in April 2010.

"We expected to see some sort of healing effect, but we did not expect to see this re-damaging effect, so that was sort of a surprise," Brodsky said. "This interplay is a much more complicated process than we anticipated seeing."

Read more at Discovery News

How 'Parrot Dinosaur' Switched from Four Feet to Two as It Grew

Tracking the growth of dinosaurs and how they changed as they grew is difficult. Using a combination of biomechanical analysis and bone histology, palaeontologists from Beijing, Bristol, and Bonn have shown how one of the best-known dinosaurs switched from four feet to two as it grew.

Psittacosaurus, the 'parrot dinosaur' is known from more than 1000 specimens from the Cretaceous, 100 million years ago, of China and other parts of east Asia. As part of his PhD thesis at the University of Bristol, Qi Zhao, now on the staff of the Institute for Vertebrate Paleontology in Beijing, carried out the intricate study on bones of babies, juveniles and adults.

Dr Zhao said: "Some of the bones from baby Psittacosaurus were only a few millimetres across, so I had to handle them extremely carefully to be able to make useful bone sections. I also had to be sure to cause as little damage to these valuable specimens as possible."

With special permission from the Beijing Institute, Zhao sectioned two arm and two leg bones from 16 individual dinosaurs, ranging in age from less than one year to 10 years old, or fully-grown. He did the intricate sectioning work in a special palaeohistology laboratory in Bonn, Germany,

The one-year-olds had long arms and short legs, and scuttled about on all fours soon after hatching. The bone sections showed that the arm bones were growing fastest when the animals were ages one to three years. Then, from four to six years, arm growth slowed down, and the leg bones showed a massive growth spurt, meaning they ended up twice as long as the arms, necessary for an animal that stood up on its hind legs as an adult.

Professor Xing Xu of the Beijing Institute, one of Dr Zhao's thesis supervisors, said: "This remarkable study, the first of its kind, shows how much information is locked in the bones of dinosaurs. We are delighted the study worked so well, and see many ways to use the new methods to understand even more about the astonishing lives of the dinosaurs."

Professor Mike Benton of the University of Bristol, Dr Zhao's other PhD supervisor, said: "These kinds of studies can also throw light on the evolution of a dinosaur like Psittacosaurus. Having four-legged babies and juveniles suggests that at some time in their ancestry, both juveniles and adults were also four-legged, and Psittacosaurus and dinosaurs in general became secondarily bipedal."

The paper is published in Nature Communications.

From Science Daily

Evidence of 2000-Year-Old Famine Found in Jerusalem

Three intact cooking pots and a small ceramic oil lamp have provided Israeli archaeologists with the first evidence for the famine and terror that spread throughout Jerusalem during the Roman siege nearly 2,000 years ago.

The items belonged to Jewish residents who took shelter in the underground water channel. They were found in a cistern near the Western Wall, not far from Robinson’s Arch in the Jerusalem Archaeological Park.

According to Eli Shukron, excavation director at the Israel Antiquities Authority (IAA), people went down into the cistern to secretly eat the food that was contained in the pots, hiding from the Roman soldiers and the Jewish rebels who would have tried to take away the frugal meal.

“This is the first time we are able to connect archaeological finds with the famine that occurred during the siege of Jerusalem at the time of the Great Revolt,” Shukron said in a statement.

Beginning in 66 A.D., the Great Revolt was the first of several Jewish rebellions against the Roman rule.

Despite remarkable resistance, the Jewish people were ultimately crushed. In 70 A.D., the Romans under Titus sacked the city and destroyed the second Temple, which, according to Jewish tradition, was built by King Herod the Great on the site of King Solomon’s temple. This was razed by the Babylonians around 587 B.C.

The Romans plundered tons of gold, silver trumpets and gold candelabra from Herod’s magnificent white and gold temple. Then they paraded the treasure, which also helped finance the building of the Colosseum, through the streets of Rome in triumph.

The new finding, said Shukrun, matches the vivid account of the historian Titus Flavius Josephus (37 – about 100). He reported the dramatic events and widespread starvation in Jerusalem, claiming that 1,100,000 people, mainly Jewish, were killed during the siege.

In his dramatic description of the famine, the historian recounted that Jewish rebels sought food in the homes of their fellow Jews. They concealed and ate whatever they had in hidden places in their homes.

“For as nowhere was there corn to be seen, men broke into the houses and ransacked them,” Josephus wrote in his book “The Jewish War.”

“If they found some, they maltreated the occupants for saying there was none; if they did not, they suspected them of having hidden it more carefully and tortured them,” he added.

Read more at Discovery News

Cave Art Reveals Ancient View of Cosmos

Some of the oldest art in the United States maps humanity's place in the cosmos, as aligned with an ancient religion.

A team of scientists has uncovered a series of engravings and drawings strategically placed in open air and within caves by prehistoric groups of Native American settlers that depict their cosmological understanding of the world around them.

"The subject matter of this artwork, what they were drawing pictures of, we knew all along was mythological, cosmological," Jan Simek, an archaeologist at the University of Tennessee said. "They draw pictures of bird men that are important characters in their origin stories and in their hero legends, and so we knew it was a religious thing and because of that, we knew that it potentially referred to this multitiered universe that was the foundation of their cosmology."

Simek and his team studied art from 44 open-air locations and 50 cave sites. The earliest depiction of this kind of cosmological stratification dates to around 6,000 years ago, but most of the art is more recent, from around the 11th to 17th centuries.

The researchers noticed that certain kinds of drawings and engravings only appear in specific areas of the plateau. For instance, open-air spots in high elevations touched by the sun feature "upper world" artistic renderings that include depictions of weather forces, heavenly bodies and characters that can exert influence on humans.

"Lower world" drawings and engravings are found in dark areas like caves that are hidden from the sun. Usually, this layer of the world is associated with death, darkness and danger.

The "middle world" is representative of the reality that surrounded prehistoric humans on a daily basis. These drawings were found in both open-air environments and caves, but for the most part, they were found in the middle elevations of the plateau.

"This layered universe was a stage for a variety of actors that included heroes, monsters and creatures that could cross between the levels," Simek said in a statement.

Although depictions of many of the actors were found in low, high and middle elevations, color relates the overall cosmological structure of the universe, Simek said. Characters drawn in red — the color of life — are found in higher elevation sites, while black was used to draw figures found in the lower world.

"The dominant things we see all together are human images, what we call anthropomorphs," Simek told LiveScience. "They're not all human; some of them are clearly mythological people or people who blend animal and human characteristics."

Read more at Discovery News

New Hooter From the Past Found Fossilized

Scientists have found a new fossil of an owl species that lived 2,000 years ago in the remote São Miguel Island off Portugal. It was likely wiped out by the arrival of human settlers in the archipelago in the 1400s.

Scientists were digging in a cave near the volcano Água de pau when they found the bones of the bird. They put the bones together like a jigsaw to figure out what the bird must have looked like.

The species, christened the São Miguel scops owl (Otus frutuosoi), adds a new species to the Otus family of owls, commonly known as scops owls. The tarsi bones of the São Miguel scops, its stick-like connections between the thighs and feet, were weak. Coupled with short wings, the owls were likely not great fliers, but rather lived on the floor of the island’s laurel forests eating insects. The work was published in the journal Zootaxa.

It was possible for the birds to live on or close to the ground because there would have been few predators on the island 2,000 years ago.

The São Miguel Island is part of the Azores Islands archipelago, located about 900 miles west of Portugal. These are volcanic islands that jut out of the ocean floor at the tectonic triple juncture where the North American Plate separates from the Eurasian Plate and the African Plate along the mid-Atlantic ridge.

At the beginning, São Miguel Island was nothing more than rock.

Over time, a very few plants, insects and birds would have crossed the ocean by chance and stumbled onto the Azores. And they would have found it difficult to fly back, given the vast ocean separating the island from the main land. The immigrant birds would have instead adapted to their new home. Over time, they would occupy niches and evolve into new species of birds unique to the island – such as a flightless owl species that feeds on insects.

Given its remoteness and size, the Azores Islands should have many endemic bird species, but it has only two. Compare that against the Madeira Islands, which has four, the Canary Islands, which has five endemic bird species, and Cape Verde which has six. Scientists have suggested that the Azores had more species that then died out.

The São Miguel scops owl, which is the first fossil discovered on the island of an extinct bird species, suggests this might be true.

The trigger of extinction is likely to be humans, the scientists suggest. That’s not an unreasonable claim given that most volcanic islands witnessed rapid extinctions once mariners took to the oceans.

Mariners settled on the Azores Islands in the 15th-century. The impact of their arrival can be indirectly surmised by examining the historical record of the nearby Canary and Madeira Islands. There, human settlers caused extinctions of a number of bird species, by hunting, introducing new species that would compete for resources, and by changing ecosystems.

Read more at Discovery News

Ancient African Coins Spark Treasure Hunt

Can a handful of ancient African coins, discovered almost 70 years ago by a lone soldier on a remote island, rewrite history?

A weathered, hand-drawn map, with an "X" marking the spot on the Australian island where the African coins were discovered, might help an international team of researchers, who will travel to the island this summer, answer that question.

The story begins over a thousand years ago, when the city of Kilwa was the richest trading center on the eastern coast of Africa.

A bustling harbor, a glittering mosque decorated with Chinese porcelain and the Husuni Kubwa palace (famed for its octagonal swimming pool) made Kilwa a premier destination for wealthy merchants, who traded African gold and ivorty for spices and perfume from the Far East.

A dazzling era ends

But the city's eminence ended when Portuguese traders, intent on controlling commerce throughout the Indian Ocean, sacked the port in the 16th century.

"The Portuguese destroyed Kilwa in the 1500s, burnt it to the ground and looted everything," Ian McIntosh, a professor of anthropology at Indiana University-Purdue University Indianapolis (IUPUI), told Australian broadcaster ABC.

The deserted, crumbling ruins of Kilwa — now a UNESCO World Heritage site located near Zanzibar in modern-day Tanzania — are all that remains of the city's former splendor.

A handful of coins

Centuries later and thousands of miles away, an Australian soldier named Maurie Isenberg was operating a World War II radar station on one of the uninhabited Wessel Islands off Australia's northern shore, CNN reports.

One day, during his off-hours, Isenberg went fishing down at the remote island's beach, where he discovered a few old, copper coins with exotic markings embedded in the sand. Isenberg tossed the coins in a tin container, where they stayed for decades.

But before he forgot about his discovery, on a map of the island hand-drawn by a fellow soldier, Isenberg drew an "X" showing where he found the coins.

In 1979, Isenberg sent the coins off for appraisal. He was astonished to discover their origin: Four of the coins were from the Dutch East India Company -- a trading company founded by the Dutch in the early 17th century -- and one of those coins dated from the late 1600s, according to CNN.

But five of the coins were minted in Kilwa and are believed to be about 1,100 to 1,200 years old (from about A.D. 900), ABC reports.

"It's a very fascinating discovery," McIntosh told CNN. "Kilwa coins have only ever been found outside of the Kilwa region on two occasions.

"A single coin was found in … Zimbabwe, and one coin was found in the Arabian Peninsula, in what is now Oman, but nowhere else," McIntosh said. "And yet, here is this handful of them in northern Australia — this is the astonishing thing."

Will 5 coins rewrite history?

The Eurocentric view of history holds that Australia, populated by Aboriginal settlers for some 60,000 years, was "discovered" by European explorers in 1606.

But since the discovery of the ancient coins, which came to the attention of McIntosh before Isenberg died in 1991, that history may need to be rewritten. McIntosh also has the old map showing where the coins were discovered.

This July, McIntosh will carry that map back to the Wessel Islands, where he's leading an international team of researchers intent on solving the mystery of how the coins found their way to a remote beach in Australia.

"We have five separate hypotheses we're looking to test about how these coins got there — each one quite different from the other," McIntosh told CNN.

Some speculate that the Portuguese sailed along Australia's northern shores much earlier than was previously known. Another hypothesis suggests that African sailors from Kilwa were hired by merchants from the Far East to navigate the seas of China.

"Once you shift from the Eurocentric focus -- and this is how it could change Australian history -- you start seeing north Australia as part of this ancient trading network which links southern Africa, Arabian Persia, India, the Spice Islands and China," McIntosh told ABC.

Read more at Discovery News

Amazingly Untouched Royal Tomb Found in Peru

A rare, undisturbed royal tomb has been unearthed in Peru, revealing the graves of three Wari queens buried alongside gold and silver riches and possible human sacrifices.

Though the surrounding site has been looted many times, this mausoleum has managed to evade grave robbers for hundreds of years, archaeologists say.

Long before the Inca built Machu Picchu, the Wari empire flourished between A.D. 700 and 1000 throughout much of present-day Peru. At a time when Paris had just 25,000 residents, the Wari capital Huari was home to 40,000 people at its height, according to National Geographic, which reported the find. (In Photos: Amazing Ruins of the Ancient World)

Despite their reach, the Wari have remained somewhat mysterious, and it is rare for archaeologists to find burials that have not been ravaged by grave robbers. In hauling away treasures, looters destroy archaeological context and information, leaving researchers grasping for answers about how ancient people lived.

But a team led by Polish and Peruvian archaeologists discovered an underground mausoleum that's being billed as the first unlooted Wari imperial tomb, sealed for centuries under 30 tons (27 metric tons) of loose stone fill.

The 1,200-year-old chamber was found in El Castillo de Huarmey, north of Lima. Milosz Giersz, an archaeologist at the University of Warsaw in Poland, told National Geographic that he first saw a faint outline of the mausoleum in aerial photographs of the site.

In digging through to the "temple of the dead," the team reportedly discovered rows of human bodies buried in a seated position (some of them suspected to be human sacrifices). They also found three Wari queens in small side chambers among valuable grave goods, such as gold tools for weaving, brilliantly painted ceramic vessels and a drinking cup carved from alabaster.

The queens may not have been laid to rest for good after they died. National Geographic also reported that there were traces of insect pupae found in the queens' bodies, suggesting that their mummies may have been periodically put out on display, left exposed to the open air, to be venerated by the living Wari people.

Read more at Discovery News

Bizarre 500-Million-Year-Old Creature Unearthed

A new fossilized, cigar-shaped creature that lived about 520 million years ago has been unearthed in Morocco.

The new-found species, Helicocystis moroccoensis, has "characteristics that place it as the most primitive echinoderm that has fivefold symmetry," said study co-author Andrew Smith, a paleontologist at the Natural History Museum in London, referring to the group of animals that includes starfish and sea urchins. Modern echinoderms typically have five-point symmetry, such as the five arms of the starfish or the sand dollar's distinctive pattern.

The primitive sea creature, described today (June 25) in the journal Proceedings of the Royal Society B, could even change its body shape from slender to stumpy. Researchers say it is a transitional animal that could help explain how early echinoderms evolved their unique body plans, Smith said.

Cambrian explosion

In 2012, Smith and his colleagues were excavating in sediments dating to about 520 million years ago in the Anti-Atlas Mountains in Morocco, when they uncovered several specimens of the strange fossil.

The creature lived on the ancient supercontinent called Gondwana during the Cambrian Explosion, a period when all creatures inhabited the seas and life on the planet diversified dramatically.

One of the oldest known echinoderms, Helicoplacus — first unearthed in the White Mountains in California — had a spiral but asymmetrical body plan. And all modern echinoderms start off as larvae with bilateral symmetry, raising the question of how and when the creatures' distinctive five-point body plan originated.

New creatures

H. moroccoensis, named after the country where it was found, had a cylindrical body that extended up to 1.6 inches (4 centimeters) long. The echinoderm's mouth was on the top of its body, and it sported a cup made of checkered plates with a small stem at its base. It had a lattice-like skeleton made of calcite.

"It's a cigar-shaped beast, and it was able to expand and contract that cigar shape," Smith told LiveScience. "Sometimes it could be short and fat, and sometimes it could be long and thin."

The tiny sea creatures changed shape using a spiraling arrangement of five ambulacra, or grooves coming from the mouth that opened and closed to capture bits of food floating in the water.

The newly discovered species is the oldest known echinoderm with five ambulacra, and could shed light on how echinoderms evolved their unique body plans, Smith said.

H. moroccoensis was also found in sediments containing several other bizarre echinoderms, many of which had wacky body plans, ranging from completely asymmetrical to bilaterally symmetrical. That wide variety suggests the creatures were going through a period of dramatic diversification around that time period, Smith said.

Read more at Discovery News

Tomatoes' Genetic History from Wild to Salad

The fruit synonymous with summer, plump tomatoes, descended from tiny wild ancestors. The genetic footprints left by that journey recently were traced by an international team of plant biologists. The deciphered DNA map of the tomato and its wild relatives points to ways that the fruit could be bred to survive in harsh, desert conditions, which may become more common as climate change reshapes the world.

Domesticated tomatoes’ (Solanum lycopersicum) DNA showed signs of the artificial selection and breeding efforts that  brought about their significantly larger, redder fruit compared with wild relatives. However, the domestication of the tomato came with genetic drawbacks.

Centuries ago, the tomato appeared on European tables after Spanish conquistadors brought the plant from its Western Hemisphere homeland. Only a few plants and seeds made the journey across the Atlantic, which created what geneticists call a bottleneck, or a serious reduction in population that resulted in lower genetic diversity.

Many of tomato genes stayed in the Aztec gardens and wilderness of the Western Hemisphere. The imported plants grown in Europe ended up with a number of potentially damaging genes, which became widespread in the cultivated plants, according to the recent study published in Proceedings of the National Academy of Sciences (PNAS). These genes may have made the domesticated tomato slower-growing and frailer than their wild kin.

Plant breeders have tried for decades to improve the domesticated tomato by cross breeding it with wild relatives. The new maps of three wild tomato relatives’ DNA (Solanum pennellii, S. habrochaites and S. pimpinellifolium), may help breeders focus on specific traits more efficiently. Genetic testing of new tomato hybrids can now look for DNA markers from wild traits that could make domestic tomatoes as hardy as their wild kin.

In particular, one desert-dwelling tomato, S. pennellii, contains genes that give it a thicker waxy coating on fruits and leaves that prevent water loss, according to the PNAS study led by University of California – Davis biologists. The leaves of the desert tomato grow smaller and have fewer openings, called stomata, used for respiration. Also, the plant has hardy roots that can tolerate saltier soil.

Read more at Discovery News