Ancient Amazon civilisation laid bare by felled forest

Uncovering civilisation (Image: Edison Caetano)

by Linda Geddes

Signs of what could be a previously unknown ancient civilisation are emerging from beneath the felled trees of the Amazon. Some 260 giant avenues, ditches and enclosures have been spotted from the air in a region straddling Brazil’s border with Bolivia.

The traditional view is that before the arrival of the Spanish and Portuguese in the 15th century there were no complex societies in the Amazon basin – in contrast to the Andes further west where the Incas built their cities. Now deforestation, increased air travel and satellite imagery are telling a different story.

“It’s never-ending,” says Denise Schaan of the Federal University of Pará in Belém, Brazil, who made many of the new discoveries from planes or by examining Google Earth images. “Every week we find new structures.” Some of them are square or rectangular, while others form concentric circles or complex geometric figures such as hexagons and octagons connected by avenues or roads. The researchers describe them all as geoglyphs.

Garden villages

Their discovery, in an area of northern Bolivia and western Brazil, follows other recent reports of vast sprawls of interconnected villages known as “garden cities” in north central Brazil, dating from around AD 1400. But the structures unearthed at the garden city sites are not as consistently similar or geometric as the geoglyphs, Schaan says.

“I firmly believe that the garden cities of Xingu and the geoglyphs were not directly related,” says Martti Pärssinen of the Finnish Cultural and Academic Institutes in Madrid, Spain, who works with Schaan. “Nevertheless, both discoveries demonstrate that [upland] areas of western Amazonia were heavily populated much before the European incursion.”

The geoglyphs are formed by ditches up to 11 metres wide and 1 to 2 metres deep. They range from 90 to 300 metres in diameter and are thought to date from around 2000 years ago up to the 13th century.

Human habitation

Excavations have unearthed ceramics, grinding stones and other signs of human habitation at some of the sites but not at others. This suggests that some had purely ceremonial roles, while others may also have been used for defence.

Unusually for defensive structures, however, earth was piled up outside the ditches, and they are also highly symmetrical. “When you think about defence you’re just building a wall or a trench,” says Schaan. “You don’t have to do calculations to make it so round or square.” Many of the structures are oriented to the north, and the team is investigating whether they might have had astronomical significance.

“Many of the great early civilisations had a riverine basis and the Amazon has long been underestimated and overlooked in that sense,” says Colin McEwan, head of the Americas section at the British Museum in London.

Successful societies

Though there is no evidence that the Amazonians built pyramids or invented written language as societies in ancient Egypt or Mesopotamia did, “in terms of a trend towards increasing social complexity and domestication of the landscape, this wasn’t just a pristine forest with isolated nomadic tribes”, McEwan adds. “These were substantive, sedentary and in the long term very successful cultures.”

While some Inca sites lie just 200 kilometres west of the geoglyphs, no Inca objects have been found at the new sites. Neither do they seem to have anything in common with Peru’s Nasca geoglyphs.

“I have no doubt that this is only scratching the surface,” says Alex Chepstow-Lusty of the French Institute for Andean Studies in Lima, Peru. “The scale of pre-Columbian societies in Amazonia is only slowly coming to light and we are going to be amazed at the numbers of people who lived there, but also in a highly sustainable fashion. Sadly, the economic development and forest clearance that is revealing these pre-Columbian settlement patterns is also the threat to having enough time to properly understand them.”

Journal reference: Antiquity, vol 83, p 1084

http://www.newscientist.com/article/mg20427383.800-ancient-amazon-civilisation-laid-bare-by-felled-forest.html

Ancient Tablets Decoded; Shed Light on Assyrian Empire

Brian Handwerk
for National Geographic News

December 9, 2009

Meticulous ancient notetakers have given archaeologists a glimpse of what life was like 3,000 years ago in the Assyrian Empire, which controlled much of the region between the Mediterranean Sea and the Persian Gulf.

Clay tablets inscribed with cuneiform, an ancient script once common in the Middle East, were unearthed in summer 2009 in an ancient palace in present-day southeastern Turkey.

(Related: “Ancient Assyrian Treasures Found Intact in Baghdad.”)

Palace scribes jotted down seemingly mundane state affairs on the tablets during the Late Iron Age—which lasted from roughly the end of the ninth century B.C. until the mid-seventh century B.C.

But these everyday details, now in the early stages of decoding, may open up some of the inner workings of the Assyrian government—and the people who toiled in the empire, experts say.

“You’re really getting at the nitty gritty of the management of the empire through these kind of records,” said Melinda Zeder, director of the archaeobiology program at the National Museum of Natural History in Washington, D.C., who was not involved in the research.

“And that does what history really should do—creates a connection between our lives and the lives of people [many] years ago,” added Zeder, a member of the National Geographic Society’s Committee for Research and Exploration. (The National Geographic Society owns National Geographic News.)

Fortified City

A team led by University of Akron archaeologist Timothy Matney has been excavating the massive mud brick palace, once inhabited by the governor of the empire’s Tushhan Province, for more than a decade.

The palace is located in Ziyaret Tepe, one of three fortified cities that the Assyrians built in the northern reach of their empire on the banks of the Tigris River.

These urban administrative centers allowed Assyrians to exploit timber, stone, and metal resources from the mountains of eastern Turkey, materials that were relatively scarce in the empire’s heartland near present-day Al Mawsil (Mosul), Iraq, Matney said.

Mystery Women

So far, the team has deciphered lists of names of 144 women on the tablets who were likely employed by the palace as agricultural workers or laborers at its granary. Yet while the tablets were written in the Late Assyrian language, the women’s names are not Assyrian, Matney said.

That means the women may have been from local indigenous populations, or part of a mass relocation of people conquered by the Assyrians in another part of the empire, Matney said.

“The Assyrians deported large numbers of people—hundreds of thousands—from one part of the empire to another in order to break up local power structures and to move agricultural workers where they needed them,” he said.

“It’s an intriguing possibility that these women may have been one group that was involved in these deportations.”

The National Museum of Natural History’s Zeder said the Assyrians were one of the very earliest empires to leave behind extensive written records.

The files can help explain how, as a political entity, the empire controlled and administrated their large territories, she said.

“It will be very interesting to see what the role of women in this economy was, and also [perhaps] what the hierarchy was—were there Assyrian overlords, or was it all locally managed?”

Race Against the Clock

But those questions may never be fully answered.

When Matney and colleagues return to Ziyaret Tepe in 2010 to look for more tablets, they’ll be racing against the clock: A planned hydroelectric dam project will swamp the region as early as 2013.

Nevertheless, Matney said, the Turkish government is supporting digs at places such as Ziyaret Tepe to discover as much as possible while such sites remain above water.

http://news.nationalgeographic.com/news/2009/12/091209-ancient-tablets-decoded.html

Feline ‘pawprint’ found in HIV genome

Jessica Hamzelou, reporter

African lions living over a million years ago may have carried an early form of HIV. Now, American microbiologists reckon they’ve found a feline genetic “pawprint” in the modern-day form of the virus.

Robert Bambara and his team at the University of Rochester in New York found a genetic sequence in the HIV genome that they think descended from an ancient gene.

The group reckon that, because the feline version of HIV – FIV – is an old virus, the newly discovered sequence might have been taken up by FIV from host lions or tigers over a million years ago.

The idea that the virus started in cats is not a new one. In 1998, virologist Jaap Goudsmit argued that ancient cats could have transmitted the virus to monkeys by licking or biting them.

Goudsmit pointed out that members of the cat family have shared their habitat with monkeys both in the East African wild and in Egyptian captivity, where monkeys were kept by the males of the household while women kept cats, both being signs of fertility.

Bambara and his team agree that it’s likely the virus was passed from ancient felines to monkeys, before being passed onto humans.

Matthew Portnoy of the National Institute of General Medical Sciences told HealthDay that the research could have ramifications for understanding the swine flu virus, which has also picked up genetic information from hosts of different species.

http://www.newscientist.com/blogs/shortsharpscience/2009/12/feline-paw-print-found-in-hiv.html

Undocumented Volcano Contributed to Extremely Cold Decade from 1810-1819

SDSU Professor Jihong Cole-Dai and his colleagues studied ice cores from Antarctica and Greenland and found evidence of a previously undocumented volcanic eruption exactly 200 years ago that contributed to the record cold decade of 1810-1819. (Credit: Image courtesy of South Dakota State University)

South Dakota State University researchers and their colleagues elsewhere in America and in France have found compelling evidence of a previously undocumented large volcanic eruption that occurred exactly 200 years ago, in 1809. The discovery helps explain the record cold decade from 1810-1819.

Researchers made the finding by analyzing chemicals in ice samples from snow-capped Antarctica and Greenland in the Arctic. The year-by-year accumulation of snow in the polar ice sheets records what is going on in the atmosphere.

“We found large amounts of volcanic sulfuric acid in the snow layers of 1809 and 1810 in both Greenland and Antarctica,” said Professor Jihong Cole-Dai of SDSU’s Department of Chemistry and Biochemistry, the lead author in an article published Oct. 25, in the scientific journal Geophysical Research Letters.

Cole-Dai said climate records show that not only were 1816 — the so-called “year without a summer” — and the following years very cold, the entire decade of 1810-1819 is probably the coldest for at least the past 500 years.

Scientists have long been aware that the massive and violent eruption in 1815 of an Indonesian volcano called Tambora, which killed more than 88,000 people in Indonesia, had caused the worldwide cold weather in 1816 and after. Volcanic eruptions have a cooling effect on the planet because they release sulfur gases into the atmosphere that form sulfuric acid aerosols that block sunlight. But the cold temperatures in the early part of the decade, before that eruption, suggest Tambora alone could not have caused the climatic changes of the decade.

“Our new evidence is that the volcanic sulfuric acid came down at the opposite poles at precisely the same time, and this means that the sulfate is from a single, large eruption of a volcano in 1809,” Cole-Dai said. “The Tambora eruption and the undocumented 1809 eruption are together responsible for the unusually cold decade.”

Cole-Dai said the Tambora eruption was immense, sending about 100 million tons of sulfur gas into the atmosphere, but the ice core samples suggest the 1809 eruption was also very large — perhaps half the size of Tambora — and would also have cooled the earth for a few years. The researchers reason that, because the sulfuric acid is found in the ice from both polar regions, the eruption probably occurred in the tropics, as Tambora did, where wind patterns could carry volcanic material to the entire world, including both poles.

Cole-Dai said the research specifically looked for and found a special indicator of sulfuric acid produced from the volcanic sulfur gas in the stratosphere.

The special indicator is an unusual make-up of sulfur isotopes in the volcanic sulfuric acid. Isotopes are different types of atoms of the same chemical element, each having a different number of neutrons, but the same number of protons. The unique sulfur isotope composition is like a fingerprint of volcanic material that has reached the stratosphere, said Cole-Dai.

The stratosphere is the second major layer of the Earth’s atmosphere, reaching from about six miles to about 30 miles above the Earth’s surface at moderate latitudes. To impact global climate, rather than local weather, the sulfur gas of a volcanic eruption has to reach up into the stratosphere and once there, be spread around the globe.

Cole-Dai’s co-authors of the article are SDSU post-doctoral researcher David Ferris and graduate student Alyson Lanciki; Joël Savarino of the Laboratoire de Glaciologie et Géophysique de l’Environment in Grenoble, France; Mélanie Baroni of CEREGE (Le Centre Européen de Recherche et d’Enseignement des Géosciences de l’Environnement) at L’Université Paul Cézanne in Aix-en-Provence, France; and Mark H. Thiemens of the University of California, San Diego.

The National Science Foundation funded the research.

Story Source:

Adapted from materials provided by South Dakota State University, via Newswise.

http://www.sciencedaily.com/releases/2009/12/091205105844.htm

Vint Cerf: Connecting with an Internet Pioneer, 40 Years Later

VINT CERF © JOI ITO, VIA WIKIPEDIA

Cerf reflects on the cobbling together of four network nodes, a moment that helped usher in the invention that changed life as we know it

By Larry Greenemeier

Forty years ago—on December 5, 1969—the U.S. Department of Defense’s Advanced Research Projects Agency (ARPA) connected four computer network nodes at the University of California, Los Angeles, (U.C.L.A.), the Stanford Research Institute in Menlo Park, Calif., U.C. Santa Barbara, and the University of Utah for the first time. This doubled the size of the embryonic ARPANET, the network that would grow over the years into the global nexus of interconnected computers we know today as the Internet.

Vint Cerf has been there from the beginning, from with his work co-developing TCP/IP (the communications protocols that the Internet uses to route information across different networks and hubs) to his present position as Google’s chief Internet evangelist.

We sat down with Cerf, who is often called “the father of the Internet,” to talk about why the ARPANET was built and how it grew to become the Internet, not to mention the pros and cons of social networks.

[An edited transcript of the interview follows.]

While we’re honoring the 40th anniversary of the first time the four-node ARPANET was connected, what in your opinion was the single most important “event” in the development of the Internet?
Choosing a single most important development is incredibly hard to do because a lot of different things had to happen before the Internet could be deployed in the fashion it is today. ARPANET validated packet switching, which was important, because without that we wouldn’t have gone down the path of toward the Internet. The idea was that you could grow a system like the Internet one network at a time and then interconnect them. In some sense the most important thing was the invention of the architecture protocols that enabled the Internet. Then came the implementation [on November 22, 1977] that interconnected different packet networks together. This included a radio network and a satellite network connected as well as the ARPANET. The most important thing in this three-network test was to show the TCP/IP protocol would link all three together.

What were your thoughts at the time, as a U.C.L.A. graduate student, when you realized ARPANET was going to be a successful endeavor? In which direction did you think the technology would go?
We could see how useful this was going to be almost immediately. The absolute first asset was remote access to people’s computers. Remote access to someone else’s time-share computer (most computers at the time were connected to mainframe servers and access was shared) was a very powerful tool. For the first time, you could use someone else’s applications rather than just the ones you wrote yourself.

The impetus for this came out of the Advanced Research Projects Agency (ARPA), which was looking to make computer technology more relevant to the military. In the late 1960s every computer science department sponsored by ARPA said they needed the most advanced computers to do this work. So ARPA came up with the idea to connect computers for resource sharing. We immediately recognized the utility of that.

Although ARPANET was initially designed for the military (and only later on became available to defense labs, university labs and the general public), was it designed with an eye toward potential commercial applications, as well?
ARPA was responsible for developing systems for military command and control, but ARPA was also interested in pushing boundaries of computer usage for military applications. ARPA wanted to solve its immediate research problems, which led to remote access. By 1985, the National Science Foundation realized the utility of this for all research institutions supported by the NSF around the United States and built the NSFNET backbone for those institutions. (In 1988 the U.S. Federal Networking Council approved the interconnection of the NSFNET with MCI’s mail system, a move that kicked off the commercialization of the Internet.)

Story Continues – http://www.scientificamerican.com/article.cfm?id=internet-pioneer-cerf

Antarctica Served as Climatic Refuge in Earth’s Greatest Extinction Event

The illustration shows the geographic location of Kombuisia antarctica in Antarctica with a reconstruction of how the animal probably looked like in life. (Credit: Jörg Fröbisch, Kenneth D. Angielczyk, and Christian A. Sidor)

The largest known mass extinction in Earth’s history, about 252 million years ago at the end of the Permian Period, may have been caused by global warming. A new fossil species suggests that some land animals may have survived the end-Permian extinction by living in cooler climates in Antarctica. Jörg Fröbisch and Kenneth D. Angielczyk of The Field Museum together with Christian A. Sidor from the University of Washington have identified a distant relative of mammals, Kombuisia antarctica, that apparently survived the mass extinction by living in Antarctica.

The new species belongs to a larger group of extinct mammal relatives, called anomodonts, which were widespread and represented the dominant plant eaters of their time.

“Members of the group burrowed in the ground, walked the surface and lived in trees,” said Fröbisch, the lead author of the study. “However, Kombuisia antarctica, about the size of a small house cat, was considerably different from today’s mammals — it likely laid eggs, didn’t nurse its young and didn’t have fur, and it is uncertain whether it was warm blooded,” said Angielczyk, Assistant Curator of Paleomammology at The Field Museum. Kombuisia antarctica was not a direct ancestor of living mammals, but it was among the few lineages of animals that survived at a time when a majority of life forms perished.

Scientists are still debating what caused the end-Permian extinction, but it was likely associated with massive volcanic activity in Siberia that could have triggered global warming. When it served as refuge, Antarctica was located some distance north of its present location, was warmer and wasn’t covered with permanent glaciers, said the researchers. The refuge of Kombuisia in Antarctica probably wasn’t the result of a seasonal migration but rather a longer-term change that saw the animal’s habitat shift southward. Fossil evidence suggests that small and medium sized animals were more successful at surviving the mass extinction than larger animals. They may have engaged in “sleep-or-hide” behaviors like hibernation, torpor and burrowing to survive in a difficult environment.

Earlier work by Fröbisch predicted that animals like Kombuisia antarctica should have existed at this time, based on fossils found in South Africa later in the Triassic Period that were relatives of the animals that lived in Antarctica. “The new discovery fills a gap in the fossil record and contributes to a better understanding of vertebrate survival during the end-Permian mass extinction from a geographic as well as an ecological point of view,” Fröbisch said.

The team found the fossils of the new species among specimens collected more than three decades ago from Antarctica that are part of a collection at the American Museum of Natural History. “At the time those fossils were collected, paleontologists working in Antarctica focused on seeking evidence for the existence of a supercontinent, Pangaea, that later split apart to become separate land masses,” said Angielczyk. The fossils collected in Antarctica provided some of the first evidence of Pangaea’s existence, and further analysis of the fossils can refine our understanding of events that unfolded 250 million years ago.

“Finding fossils in the current harsh conditions of Antarctica is difficult, but worthwhile,” said Angielczyk. “The recent establishment of the Robert A. Pritzker Center for Meteoritics and Polar Studies at The Field Museum recognizes the growing importance of the region,” he said.

This research is part of a collaborative study of Dr. Jörg Fröbisch (Department of Geology, Field Museum, Chicago), Dr. Kenneth D. Angielczyk (Department of Geology, Field Museum, Chicago), and Dr. Christian A. Sidor (Burke Museum and Department of Biology, University of Washington), which will be published online December 3, 2009 in Naturwissenschaften.

Funding for this research was provided through a Postdoctoral Research Fellowship of the German Research Foundation (Deutsche Forschungsgemeinschaft) to J. Fröbisch and grants of the National Science Foundation to C. A. Sidor.

Story Source:

Adapted from materials provided by Field Museum, via EurekAlert!, a service of AAAS.

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Journal Reference:

1. Jörg Fröbisch, Kenneth D. Angielczyk, Christian A. Sidor. The Triassic dicynodont Kombuisia (Synapsida, Anomodontia) from Antarctica, a refuge from the terrestrial Permian-Triassic mass extinction. Naturwissenschaften, 2009; DOI: 10.1007/s00114-009-0626-6

http://www.sciencedaily.com/releases/2009/12/091202205621.htm

How Did Flowering Plants Evolve to Dominate Earth?

Colorful tulips and other spring flowers in the Keukenhof Gardens, the Netherlands. How did flowering plants come to dominate plant life on earth? (Credit: iStockphoto/Monika Lewandowska)

To Charles Darwin it was an ‘abominable mystery’ and it is a question which has continued to vex evolutionists to this day: when did flowering plants evolve and how did they come to dominate plant life on earth? A new study in Ecology Letters reveals the evolutionary trigger which led to early flowering plants gaining a major competitive advantage over rival species, leading to their subsequent boom and abundance.

The study, by Dr Tim Brodribb and Dr Taylor Field of the University of Tasmania and University of Tennessee, used plant physiology to reveal how flowering plants, including crops, were able to dominate land by evolving more efficient hydraulics, or ‘leaf plumbing’, to increase rates of photosynthesis.

“Flowering plants are the most abundant and ecologically successful group of plants on earth,” said Brodribb. “One reason for this dominance is the relatively high photosynthetic capacity of their leaves, but when and how this increased photosynthetic capacity evolved has been a mystery.”

Using measurements of leaf vein density and a linked hydraulic-photosynthesis model, Brodribb and Field reconstructed the evolution of leaf hydraulic capacity in seed plants. Their results revealed that an evolutionary transformation in the plumbing of angiosperm leaves pushed photosynthetic capacity to new heights.

The reason for the success of this evolutionary step is that under relatively low atmospheric C0₂ conditions, like those existing at present, water transport efficiency and photosynthetic performance are tightly linked. Therefore adaptations that increase water transport will enhance maximum photosynthesis, exerting substantial evolutionary leverage over competing species.

The evolution of dense leaf venation in flowering plants, around 140-100 million years ago, was an event with profound significance for the continued evolution of flowering plants. This step provided a ‘cretaceous productivity stimulus package’ which reverberated across the biosphere and led to these plants playing the fundamental role in the biological and atmospheric functions of the earth.

“Without this hydraulic system we predict leaf photosynthesis would be two-fold lower then present,” concludes Brodribb. “So it is significant to note that without this evolutionary step land plants would not have the physical capacity to drive the high productivity that underpins modern terrestrial biology and human civilisation.”

Story Source:

Adapted from materials provided by Wiley-Blackwell, via EurekAlert!, a service of AAAS.

http://www.sciencedaily.com/releases/2009/12/091201100221.htm

Decoding an Ancient Computer: Greek Technology Tracked the Heavens ( Preview )

Ancient Greeks knew how to calculate the recurring patterns of lunar eclipses thanks to observations made for centuries by the Babylonians. The Antikythera mechanism would have done those calculations for them—or perhaps for the wealthy Romans who could afford to own it. The depiction here is based on a theoretical reconstruction by the author and his collaborators. Jean-Francois Podevin and Tony Freeth

New explorations have revealed how the Antikythera mechanism modeled lunar motion and predicted eclipses, among other sophisticated tricks

By Tony Freeth

Key Concepts

• The Antikythera mechanism is a unique mechanical calculator from second-century B.C. Greece. Its sophistication surprised archaeologists when it was discovered in 1901. But no one had anticipated its true power.
• Advanced imaging tools have finally enabled researchers to reconstruct how the device predicted lunar and solar eclipses and the motion of the moon in the sky.
• Inscriptions on the mechanism suggest that it might have been built in the Greek city of Syracuse (now in modern Sicily), perhaps in a tradition that originated with Archimedes.

If it had not been for two storms 2,000 years apart in the same area of the Mediterranean, the most important technological artifact from the ancient world could have been lost forever.

The first storm, in the middle of the 1st century B.C., sank a Roman merchant vessel laden with Greek treasures. The second storm, in A.D. 1900, drove a party of sponge divers to shelter off the tiny island of Antikythera, between Crete and the mainland of Greece. When the storm subsided, the divers tried their luck for sponges in the local waters and chanced on the wreck. Months later the divers returned, with backing from the Greek government. Over nine months they recovered a hoard of beautiful ancient Greek objects—rare bronzes, stunning glassware, amphorae, pottery and jewelry—in one of the first major underwater archaeological excavations in history.

http://www.scientificamerican.com/article.cfm?id=decoding-an-ancient-computer

Big Freeze Plunged Europe Into Ice Age in Months

New research shows that switching off the North Atlantic circulation can force the Northern hemisphere into a mini ‘ice age’ in a matter of months. Previous work has indicated that this process would take tens of years. (Credit: iStockphoto/Trevor Hunt)

In the film The Day After Tomorrow, the world enters the icy grip of a new glacial period within the space of just a few weeks. Now new research shows that this scenario may not be so far from the truth after all.

William Patterson, from the University of Saskatchewan in Canada, and his colleagues have shown that switching off the North Atlantic circulation can force the Northern hemisphere into a mini ‘ice age’ in a matter of months. Previous work has indicated that this process would take tens of years.

Around 12,800 years ago the northern hemisphere was hit by a mini ice-age, known by scientists as the Younger Dryas, and nicknamed the ‘Big Freeze’, which lasted around 1300 years. Geological evidence shows that the Big Freeze was brought about by a sudden influx of freshwater, when the glacial Lake Agassiz in North America burst its banks and poured into the North Atlantic and Arctic Oceans. This vast pulse, a greater volume than all of North America’s Great Lakes combined, diluted the North Atlantic conveyor belt and brought it to a halt.

Without the warming influence of this ocean circulation temperatures across the Northern hemisphere plummeted, ice sheets grew and human civilisation fell apart.

Previous evidence from Greenland ice cores has indicated that this sudden change in climate occurred over the space of a decade or so. Now new data shows that the change was amazingly abrupt, taking place over the course of a few months, or a year or two at most.

Patterson and his colleagues have created the highest resolution record of the ‘Big Freeze’ event to date, from a mud core taken from an ancient lake, Lough Monreach, in Ireland. Using a scalpel layers were sliced from the core, just 0.5mm thick, representing a time period of one to three months.

Carbon isotopes in each slice reveal how productive the lake was, while oxygen isotopes give a picture of temperature and rainfall. At the start of the ‘Big Freeze’ their new record shows that temperatures plummeted and lake productivity stopped over the course of just a few years. “It would be like taking Ireland today and moving it up to Svalbard, creating icy conditions in a very short period of time,” says Patterson, who presented the findings at the European Science Foundation BOREAS conference on humans in the Arctic, in Rovaniemi, Finland.

Meanwhile, their isotope record from the end of the Big Freeze shows that it took around two centuries for the lake and climate to recover, rather than the abrupt decade or so that ice cores indicate. “This makes sense because it would take time for the ocean and atmospheric circulation to turn on again,” says Patterson.

Looking ahead to the future Patterson says there is no reason why a ‘Big Freeze’ shouldn’t happen again. “If the Greenland ice sheet melted suddenly it would be catastrophic,” he says.

This study was part of a broad network of 38 individual research teams from Europe, Russia, Canada and the USA forming the European Science Foundation EUROCORES programme ‘Histories from the North — environments, movements, narratives’ (BOREAS). This highly interdisciplinary initiative brought together scientists from a wide range of disciplines including humanities, social, medical, environmental and climate sciences.

Story Source:

Adapted from materials provided by European Science Foundation.

http://www.sciencedaily.com/releases/2009/11/091130112421.htm

3-D Renderings Bring Ancient Hominids to Life

By Brandon Keim

For decades, paleoartists have told the story of human evolution through sculpture and drawing. Now their tools have evolved, too.

Computers allow a level of detail and control that isn’t possible with other media. Their creations can come closer than ever to bringing our ancestors to life.

“What’s driven my work has always been, ‘I want to see that thing alive. I want to see that world,” said paleoartist Viktor Deak, who provided the reconstructions used in the Becoming Human documentaries, which aired in November on PBS. “Computer graphics is developing to the point where, in movies like “Benjamin Button,” you don’t know what parts are not digital.”

Deak still begins his reconstructions in traditional fashion, sculpting bodies from clay. Like other paleoartists, he doesn’t know what his fossil interpretation will look like when complete, but comes to an understanding of anatomic nuances, of tissue and muscle thickness and how it might have linked to ancient bone, while working with his hands in three dimensions.

 

Once he’s done, he converts the work to digital format. For a 78-foot-long mural now traveling with Lucy’s Legacy, a touring exhibition featuring the famous 3.2 million year old fossils, he photographed his sculptures and imported them to Photoshop. There he added hundreds of layers of texture and light, tweaking them for maximum combinatorial realism.

That was the old way. For Becoming Human, he worked with ZBrush, a 3-D modeling program that lets him work with the sculpture in even greater detail. “The nuances of the skin, the way light scatters underneath it, they figured all that out,” he said of the program’s naturalism. “There’s no limitation on what you can do, as long as your machine can handle it.” He poses his sculptures in desired position, then renders it with different materials and lighting. The renderings are then sent to Photoshop, layered and tweaked for maximum realism.

“They look realer to me,” said Deak. “For a couple seconds, people might say, ‘What’s that a photo of? Where’d you get that picture? There’s that moment of belief when they’re not looking at it as a painting or sculpture, but as a living thing.”

“He does wonderful stuff,” said Rick Potts, curator of anthropology at the Smithsonian’s National Museum of Natural History. Potts described the digital transition as something that many artists have greeted reluctantly if at all, but is necessary.

“I’m excited about it, because it means you’re not just dealing with static appearance,” he said. “One of the great challenges of science communication is taking dead, dusty things we find in the ground, and helping people understand that these were part of a living world. Our ancestors were living and dying, just as we do. Bringing things to life in the digital world can really help.”

The ultimate form of resurrection is as animation, which was done in Becoming Human by mapping Deak’s models onto the motion recordings of suited human actors. But no human can ever move quite like a creature with a different skeleton, and relying on other people to realize his ideas of how ancient hominids moved adds an extra layer of separation.

“Learning animation is my goal right now. That would cross out any ambiguity between the science and the final depiction of it. Once I get the software down, then I can do the whole thing and create the vision of human evolution I have banging around in my brain,” said Deak.

Of course, whatever the tool, the task is still poised at what Potts called “the edge of science and art.” Even for scientists, fossils are heavily interpreted — Lucy, the most complete ancient hominid skeleton, is only 40 percent complete — and Deak immerses himself in the field’s literature, taking in every new find and revision.

“I’m an anthropologist who happens to do art. I don’t write that well and would get bored doing 30-page papers on mandible synthesis,” said Deak. “In my mind I have a tree of skulls that I’m always repositioning and thinking about. As much thinking and analysis as possible goes into each work. I’ve taken it upon myself to be a voice for these fossils.”

Images: 1) A finished Homo ergaster, from Becoming Human. 2) Detail from the mural for Lucy’s Legacy. 3) Early- and late-stage renderings of Homo heidelbergensis. 4) Viktor Deak in his studio.
See Also:

• Nov. 24, 1974: Humanity, Meet Lucy. She’s Your Mom
• Lucy 2.0: Famous Fossil Hominid Goes Digital
• Humanity Has New 4.4 Million-Year-Old Baby Mama
• Vote for Your Favorite Dinosaur Illustration

Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecosystem and planetary tipping points.

http://www.wired.com/wiredscience/2009/11/viktor-deak-paeoartist/