Use-wear Archaeologist

‘Amenemhat II’ at Metropolitan Museum - Review

2011-08-29T17:03:00.000-07:00

A giant 4,000-year-old Egyptian visitor looms over the crowd of live humans milling antlike throughout the vast entry hall of the Metropolitan Museum of Art. He is an extraordinary specimen of regal manhood. Carved from a single block of dark gray granodiorite, he sits in a form-fitting kilt on a cubic throne covered by hieroglyphics. He has the broad shoulders, narrow waist and muscular legs of a well-developed athlete. Sporting a headdress of folded striped fabric, he gazes out over the masses with imperturbable self-assurance and open eyes set in a round, youthful face. He is as thrilling as anything in the Met’s great Egyptian collection.

Metropolitan Museum This pharaoh, 4,000 years old and 10 feet tall, comes to the Great Hall from Berlin; he is to stay for 10 years. More Photos »

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Scholars think this 10-foot tall, almost nine-ton monument originally portrayed the 12th-dynasty pharaoh Amenemhat II, who reigned from about 1919 to 1885 B.C. Later artists evidently altered the facial features to make him more like Ramesses II, the king who ruled from about 1279 to 1213 B.C. He has belonged to Berlin’s Egyptian Museum and Papyrus Collection since 1837. But now the courtyard in Germany where he usually presides is under reconstruction, so he will be a guest of honor in New York for the next 10 years.

Ancient Egyptian art has captivated Western imaginations for a long time. It inspired the ancient Greeks and Romans and the artists and intellectuals of the European Renaissance. In the 19th century it caused a veritable epidemic of Egyptomania, which infected Art Deco design in the 20th century, along with scores of scary movies, from “The Mummy” of 1932 to “The Mummy” of 1999.

“Amenemhat II” feels at once deeply familiar and otherworldly. Its tension between geometric abstraction and organic naturalism, its ambition to transform inert material into something that seems to live and breathe, anticipates the basic aesthetic terms that would define Western art from the Greeks to the start of Modernism. Despite its rigid stillness, the statue has an uncanny animated feeling, as if it were inhabited by some eternal consciousness. That, at least, is what the Egyptians wanted their viewers to experience. For them the pharaoh was truly a divine being.

Around the time “Amenemhat II” was created, Egyptian artists achieved something close to perfection in sculpture, and the idea of such exacting excellence as something to aim for — in art and in life — must be counted among the Egyptians’ important contributions to human history. Before then, it seems, people just did the best they could. But the trouble with perfection is that it cannot be exceeded, which may explain why Egyptian art changed so little over its 5,000 years (and why fascists are so fond of it). For a viewer accustomed to the churn of styles in a world of historical flux, “Amenemhat II” seems an emissary from a place where time stands still.

A year from now “Amenemhat II” will be moved into the Met’s Egyptian wing. That should be a good thing. Big as it is, it is dwarfed by the expanse of the Great Hall, and its aura of silent majesty is dampened by the distracting bustle of ordinary mortals. It needs a room of its own to frame its awesomeness properly.

“Amenemhat II” is at the Metropolitan Museum of Art; (212) 535-7710, metmuseum.org.

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Earliest image of Egyptian ruler wearing 'white crown' of royalty brought to light

2011-08-29T13:07:00.000-07:00

ScienceDaily (Aug. 5, 2011) — The earliest known image of an Egyptian ruler wearing the "White Crown" associated with Egyptian dynastic power has been brought to light by an international team of archaeologists led by Egyptologists from Yale University.

Carved around 3200 BCE, this unique record of a royal celebration at the dawn of the Egyptian dynastic period was found at a site discovered almost a half-century ago by Egyptologist Labib Habachi at Nag el-Hamdulab, on the West Bank of the Nile to the north of Aswan.

The site had been partially damaged in recent years, and the Yale-led team -- which also included Egyptologists from the University of Bologna, Italy and the Provinciale Hogeschool of Limburg, Belgium -- relied on Habachi's photos (now stored with the Epigraphic Survey in Luxor) and cutting-edge digital methodology to reconstruct and analyze the images and hieroglyphic text inscribed in several areas within the larger site.

According to Maria Carmela Gatto, director of the project, the group of images and the short inscription represent the earliest depiction of a royal Jubilee, complete with all the identifying elements of the Early Dynastic period known from later documents, such as the so-called Palermo Stone (Egyptian royal annals from the First through the Fifth Dynasties): an Egyptian ruler wearing a recognizable Egyptian crown, and an inscription alluding to "the Following of Horus," i.e., the royal court.

John Coleman Darnell, director of the Yale Egyptological Institute in Egypt, professor of Egyptology, and chair of the Near Eastern Languages and Civilization Department, whose important discovery of a Middle Kingdom city in the Egyptian Western Desert was reported a year ago, says: "The Nag el-Hamdulab scenes are unique, and bridge the world of the ritual Predynastic Jubilee in which images of power -- predominately boats and animals -- are the chief elements, and the world of the royal pharaonic Jubilee, in which the image of the human ruler dominates the events. The Nag el-Hamdulab cycle of images reveal the emergence of the ruler as supreme human priest and incarnate manifestation of human and divine power.

Furthermore, he notes, "The Nag el-Hamdulab cycle is the last of the old nautical Jubilee cycles of the Predyanstic Period, and the first of the pharaonic cycles over which the king, wearing the regalia of kingship -- here the oldest form of the White Crown -- presides. The Nag el-Hamdulab cycle is also the first of such images with a hieroglyphic annotation."

Darnell translated the text, in which a reference to a vessel of the "Following" (from the "Following of Horus") leads him to speculate that the inscription is the earliest record of Egyptian tax collection and the first expression of royal economic control over Egypt and "perhaps at least some portion of northern Nubia."

Darnell, Stan Hendrickx of Belgium and Gatto date the Nag el-Hamdulab cycle of images to the late Naqada period, around 3200 BCE, the time between the beginning of Dynasty 0 and Narmer, first ruler of Dynasty 1. Darnell, who has considerable experience with early Egyptian rock inscriptions, said the latest finding from Nag el-Hamdulab is so important that it already figures in a new documentary series from Germany, which will soon be available worldwide.

The Aswan-Kom Ombo Archaeological Project -- AKAP -- is a joint venture between Yale and the University of Bologna, led by Gatto and Antonio Curci, with an international research team from Europe, America and Egypt that includes Hendrickx and Darnell. Now in its seventh season, the project aims to survey and rescue the archaeology of the region between Aswan and Kom Ombo, in the southern part of Upper Egypt.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Yale University.

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

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AGU Fall Meeting: News media registration opens; book hotels now

2011-08-29T08:56:00.000-07:00

Public release date: 17-Aug-2011
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Contact: Maria-Jos? Vi?as
mjvinas@agu.org
202-777-7530
American Geophysical Union

Contents of this message:

Find out what's new (and important) in the Earth and space sciences U.S. visa regulations for international reporters Book hotel rooms now for the best selection News Media registration information News Media Registration Form

1. Find out what's new (and important) in the Earth and space sciences

The American Geophysical Union's Fall Meeting returns to the Moscone Convention Center, located at 747 Howard St. in San Francisco, California. The dates are Monday?Friday, 5-9 December 2011. More than 19,000 scientists from all over the world are expected to assemble for this premier meeting of the Earth and space sciences. The meeting will take place in the convention center's West, North and South buildings.

For journalists, Fall Meeting is an opportunity to learn about the latest research in fields as diverse as climate change, space weather, planetary exploration, volcanism and seismology, and Earth's magnetic field?just for starters. The preliminary program lists over 880 scientific sessions, which are described at http://sites.agu.org/fallmeeting/scientific-program/session-search/ . Note: Some of these proposed sessions may be dropped or modified, and others added.

For public information officers of universities, government agencies, and research institutions, Fall Meeting is an opportunity to present your research to more than 150 reporters through press releases, participation by your scientists in press conferences, and of course one-on-one contact with the media. Please get in touch with us if you are interested in pitching us press conference ideas.

A link to our online News Media Registration Form for use by both reporters and PIOs is at the end of this message.

A full program of press conferences is in development and will be announced in later advisories.

NOTE: We will not be organizing a field trip for News Media registrants this year.

2. U.S. visa regulations for international reporters

All journalists who are not United States citizens or permanent residents need a visa to cover scientific meetings in the U.S. This applies equally to journalists from "Visa Waiver Program" countries (e.g., Western Europe), who do not normally need visas to enter the U.S. as tourists. This is not a new requirement, but it is now being enforced strictly.

The visa for journalists is an "I" visa, issued by the American Embassy or an American Consulate in your home country. If you are planning to cover Fall Meeting, please apply early for your "I" visa. The procedure is not complicated, but depending on the volume of total visa applications, it may take some time to be issued.

The U.S. Department of State has posted a fact sheet about visas for journalists on its Web site, which you are urged to consult: http://travel.state.gov/visa/temp/types/types_1276.html

3. Book hotel rooms now for the best selection

With over 19,000 scientists and some 200 journalists and press officers expected at Fall Meeting, it makes sense to book your hotel room now at preferential rates. Cancellations are allowed without penalties up to 72 hours prior to arrival. By booking now, you are more likely to get your preferred location or rate, whichever is your top priority.

Thirty-eight hotels offer rooms at rates starting as low as $97 per day, plus tax. Hotel reservations are made on a first-come, first-served basis. Special AGU room rates are subject to availability after the 1 November reservations deadline.

To see the list of available hotels, their rates and amenities, as well as a map (red circle with a white "C" is Moscone Convention Center West and South), and an online booking form, go to https://www.cmrhousing.com/AGU_6U/Welcome.aspx

NOTE: AGU will not be providing shuttle service from the hotels to Moscone Center this year.

4. News Media registration information

News Media registrants receive, at no charge, a badge that provides access to any of the scientific sessions of the meeting, as well as to the Press Room and Press Conference Room. The locations of these rooms have not yet been finalized. No one will be admitted without a valid badge.

Eligibility for press registration is limited to the following persons:

Working press employed by bona fide news media: must present a press card, business card, or letter of introduction from an editor of a recognized publication. Freelance science writers: must present one of the following: a current membership card from NASW, CSWA, ISWA, SEJ, or one of the 38 other associations of science journalists recognized by the World Federation of Science Journalists; or evidence of bylined work pertaining to science intended for the general public and published in 2010 or 2011; or a letter from the editor of a recognized publication assigning you to cover Fall Meeting. Public information officers of scientific societies, educational institutions, and government agencies: must present a business card.

Note: Representatives of publishing houses, for-profit corporations, and the business side of news media must register at the main registration desk at the meeting and pay the appropriate fees, regardless of possession of any of the above documents; they will not be accredited as News Media at the meeting.

Scientists who are also reporters and who are presenting at this meeting (oral or poster session) may receive News Media credentials if they qualify (see above), but must also register for the meeting and pay the appropriate fee as a presenter.

5. News Media Registration Form

The News Media Registration Form is set up for online submission only. Go to: http://registration.experient-inc.com/showagu111?link=press

The last day for advance News Media registration, assuring that your badge will be waiting for you when you arrive, is Monday, 28 November 2011. You may also register onsite at Moscone Center.

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Ancient wild horses help unlock past

2011-08-29T05:50:00.000-07:00

Public release date: 23-Aug-2011
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Contact: David Garner
david.garner@york.ac.uk
44-019-043-22153
University of York

An international team of researchers has used ancient DNA to produce compelling evidence that the lack of genetic diversity in modern stallions is the result of the domestication process.

The team, which was led by Professor Michi Hofreiter from the University of York, UK, has carried out the first study on Y chromosomal DNA sequences from extinct ancient wild horses and found an abundance of diversity.

The results, which are published in Nature Communications, suggest the almost complete absence of genetic diversity in modern male horses is not based on properties intrinsic to wild horses, but on the domestication process itself.

Professor Hofreiter said: "Unlike modern female domestic horses where there is plenty of diversity, genetic diversity in male horses is practically zero.

"One hypothesis to explain this suggests modern horses have little Y chromosome diversity because the wild horses from which they were domesticated were also not diverse, due in part to the harem mating system in horses, implying skewed reproductive success of males. Our results reject this hypothesis as the Y chromosome diversity in ancient wild horses is high. Instead our results suggest that the lack of genetic diversity in modern horses is a direct consequence of the domestication process itself."

The Y chromosome is a valuable tool in population genetics, providing a means of directly assessing evolutionary processes that only affect the paternal lineage. So far mitochondrial DNA studies have failed to discover the origin of domestic horses. However, these new Y chromosomal markers now open the possibility of solving this issue in detail.

As part of the study, researchers sequenced Y chromosomal DNA from eight ancient wild horses dating back from around 15,000 to more than 47,000 years and a 2,800-year-old domesticated horse. The results were compared to DNA sequences from Przewalski horses - the only surviving wild horse population ? and 52 domestic horses, representing 15 modern breeds, which had been sequenced previously.

Domestication of horses dates back approximately 5,500 years. DNA from the skeletal remains of a 2,800-year-old domesticated stallion from Siberia showed that in contrast to modern horses, Y chromosomal diversity still existed several thousand years after the initial domestication event for horses.

Professor Hofreiter said: "This suggests some level of Y chromosomal diversity still existed in domestic horses several thousand years after domestication, although the lineage identified was closely related to the modern domestic lineage."

The study was carried out in Germany by Sebastian Lippold, from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. The results were then independently replicated at the Centre for GeoGenetics at Copenhagen University, Denmark.

Sebastian Lippold said: "Working on ancient Y chromosomal DNA was especially challenging but the only opportunity to investigate Y chromosomal diversity in wild horses. For now we have a first idea of ancestral diversity and therefore a better impression of how much diversity has been lost. Basically this was an important first step and points to the potential the Y chromosomal marker could have in order to further investigate domestication history in horses."

Beth Shapiro, an Assistant Professor in the Department of Biology at the Pennsylvania State University, USA, carried out the analysis and interpretation.

She said: "Most ancient DNA research until now has focused on a different part of the genome ? the mitochondrion ? which is much more abundant in cells and therefore much easier to work with when the DNA is degraded. This has been a serious limitation in ancient DNA research, because we generally only have a good idea what happened along the maternal line. Here, we've been able to look at what happened along the paternal lineage, and, probably unsurprisingly, we see something different going on in males than in females.

"This is exciting stuff, and means we can start getting a much better picture of how events like domestication and climate change have shaped the diversity of organisms alive today."

Researchers had found that Przewalski's horse displays DNA haplotypes not present in modern domestic horses, suggesting they are not ancestral to modern domestic horses. However, while the Y chromosome data supported historic isolation, it also suggests a close evolutionary relationship between the domestic horse and the Przewalski's horse, since the Przewalski Y chromosomal haplotype is more similar to the two domestic ones than any of the ancient wild horse haplotypes.

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ARCHAEOLOGY, September/October 2011

2011-08-29T01:18:00.000-07:00

Editor's Letter: Issues of Scale

This issue of ARCHAEOLOGY makes one thing clear: Anything at all can be regarded as an artifact. Investigation of the past can feature undertakings as outsized as lifting an entire ship from the bottom of the sea—with even the silt surrounding it intact—as in "Pirates of the Marine Silk Road." Here, author Lauren Hilgers gives us a lead on just how quickly marine archaeology and preservation are proceeding in China, and discusses the latest evidence of Ming Dynasty trade.

In "The Edible Seascape," science writer Jude Isabella reports that what once seemed to be random rock formations along the northwest coast of North America are now being understood as technologies engineered by ancient peoples to manage their supply of fish and other seafood. The most significant artifacts? Fish bones no larger than your fingernail.

Much of the evidence gathered in Virginia and North Carolina's Great Dismal Swamp is even more miniscule, but nonetheless poignant testament to the determination of the escaped slaves who built self-sufficient communities in some of the most inhospitable territory imaginable. In "Letter From Virginia: American Refugees," journalist Marion Blackburn tells their story.

"Defending a Jungle Kingdom," by senior editor Zach Zorich, provides new, landscape-wide evidence from the border zone between Mexico and Guatemala of the intensely competitive relationship between the ancient Maya cities of Yaxchilan and Piedras Negras.

Of course, there's much more. Fragile murals offer a new point of view on the ancient Peruvian elite. The Persian Empire's eastern extent is explored. And there are new clues about a long-standing mystery centering on hundreds of broken Bronze Age figurines.

Finally, through the considered work of artist Gary Staab, detailed in "Pompeii's Dead Reimagined" by executive editor Jarrett A. Lobell, we are invited to reflect on the meaning of the word artifact.

I also would like to say a word about a colleague who has been extremely important to us. This is the 65th issue of ARCHAEOLOGY that design director Ken Feisel has helped us produce. Ken was originally brought on board in 1999 to design dig, our former archaeology publication for children, and quickly took on responsibilities here at the "grown up" magazine. He has created countless maps and vivid layouts—all providing the essential visual side of the archaeology story. Ken will be leaving us as we send this issue to press, and I know we will all miss waiting for him to say, as he sorts through images of far-flung sites, exotic landscapes, and artifacts of all shapes and sizes, "Oh...now that's cool."

Claudia Valentino
Editor in Chief

Features

Pirates of the Marine Silk Road
A shipwreck in the South China Sea advances China's emerging field of underwater archaeology
by Lauren Hilgers

Hidden Scenes of a Royal Court
Thirty years after they were first glimpsed, murals reveal a vibrant life in ancient Peru
by Roger Atwood

The Edible Seascape
A reevaluation of evidence along North America's western coast shows how its earliest inhabitants managed the sea's resources
by Jude Isabella

Defending a Jungle Kingdom
Newly uncovered fortifications reveal how ancient Maya rulers struggled for wealth and territory
by Zach Zorich

Pompeii's Dead Reimagined
An artist interprets the ancient city's most evocative artifacts
by Jarrett A. Lobell

Edge of an Empire
An ancient Afghan fortress offers rare evidence of Persia's forgotten eastern territories
by Andrew Lawler

Departments

From the President
The Belitung Shipwreck
by Elizabeth Bartman

From the Trenches

World Roundup
Artifacts track the birth of the African-American middle class, how llama dung sustained the Incas, a fungus in Tut's tomb, and did the Neanderthals meet their end in the Arctic Circle?

Letter from Virginia
Thousands of escaped slaves made a new life in one of the world's most unwelcoming places—the Great Dismal Swamp—for a chance at self-determination

Artifact
A tombstone tells the 1,800-year-old story of a Roman gladiator felled by a ref's bad call

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Indian Ocean pirates impede climate observations

2011-08-28T21:15:00.000-07:00

Public release date: 9-Aug-2011
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Contact: Craig Macaulay
Craig.Macaulay@csiro.au
61-362-325-219
CSIRO Australia

Australian scientists have sought the help of the United States and Australian navies to plug a critical gap in their Argo ocean and climate monitoring program caused by Somali pirates operating in the western Indian Ocean."We have not been able to seed about one quarter of the Indian Ocean since the increase in the piracy and that has implications for understanding a region of influence in Australian and south Asian weather and climate," says CSIRO Wealth from Oceans Flagship scientist, Dr Ann Thresher.

Over 30 nations contribute to the multi-million dollar Argo project, in which 3,000 robotic instruments provide near real-time observations of conditions such as heat and salinity in the top 2,000 metres of the ocean.

Australia, through CSIRO and the Integrated Marine Observing System (IMOS), ranks second among countries based on the number of profilers providing data, with more than 325 profilers reporting to international data centres from the Indian, Pacific and Southern Oceans and the Tasman Sea. At nearly two metres in length the drifting profilers, or 'floats', are programmed to drift at 1000m for 10 days, then fall to 2000m and sample as they ascend to the surface to upload their data to satellites.

Although the Argo project offers shipping and defence benefits, its primary objective is to monitor ocean heat and salinity patterns that drive the climate and monsoonal systems which bring rain to Australia.

Dr Thresher said the program is heavily reliant on commercial shipping and research and chartered vessels to deploy the instruments."With the region north of Mauritius being a no-go area for most vessels due to pirate activity, we have approached the US and Australian navies to assist us in deployments of around 20 profilers, including 10 provided by the United Kingdom Argo project.

"This level of international and military cooperation is tremendously important to us in building a sustainable operating ocean-borne system that is providing the data at the core of current weather and climate observations and prediction," Dr Thresher said.

CSIRO is shipping one profiler to Florida for deployment by the US Navy, and is asking the Royal Australian Navy for help deploy another eight instruments in the area of highest risk.

A 20-metre South African yacht, Lady Amber, is under charter to CSIRO and has successfully deployed seven instruments near Mauritius in the Western Indian Ocean. Her working area, however, was severely restricted by pirate activity in this area and the positions of several profilers had to be changed to accommodate these restrictions. She will deploy another 15 instrument as she transits between Mauritius and Fremantle, where she will pick up another 39 floats for deployment northwest of the Australian North West Shelf ? an area thankfully free of piracy.

The International Argo Steering Team is co-chaired by CSIRO oceanographer, Dr Susan Wijffels and Professor Dean Roemmich from the Scripps Institution of Oceanography (US).

Dr Wijffels said Argo is now an essential climate and ocean-observing infrastructure and researchers are continuing to review its coverage to ensure gaps in the global network do not open us, such as in the western Indian Ocean. In the future Argo measurements might extend below 2,000 metres and reach into the ocean beneath the polar ice, where currently few measurements are routinely made

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Gene study sheds new light on origins of British men

2011-08-28T17:31:00.000-07:00

Public release date: 24-Aug-2011
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Contact: Eleanor Cowie
eleanor.cowie@ed.ac.uk
44-131-650-6514
University of Edinburgh

New genetic evidence reveals that most British men are not descended from immigrant farmers who migrated east 5,000-10,000 years ago ? contrary to previous research.

Instead, scientists from the Universities of Oxford and Edinburgh say that most European men can trace their lineage to people ? most likely hunter-gatherers ? who had settled in Europe long before that time.

The latest study, based on the most common genetic lineage in European males, aims to correct an analysis of genetic data, published last year. It had reported that most British men came from people who migrated west, with the spread of agriculture, from the Near East.

More than 100 million European men have a set of genes called R-M269, including about three-quarters of British men. A key question in understanding the peopling of Europe is when this group spread out across Europe.

Researchers say their work shows that the set of genes chosen to estimate the age of this group of men vary the outcome enormously. They add that the previously reported east-west pattern is not found in their larger and more comprehensive dataset. This, the Oxford ? Edinburgh team says, leaves little evidence for a farmer-led dispersal of this major group.

According to Dr Cristian Capelli, the Oxford geneticist who led the research, the study "resets" the debate on the peopling of Europe. He says, "Our works overturns the recent claims of European Y chromosomes being brought into the continent by farmers."

Co-author, Dr Jim Wilson of the University of Edinburgh's Centre for Population Health Sciences, adds that the paper shows for the first time that certain properties of the genes studied strongly influence the accuracy of the date estimate.

"Estimating a date at which an ancestral lineage originated is an interesting application of genetics, but unfortunately it is beset with difficulties and it is very difficult to provide good dates. Many people assume that the more genes the more accurate the dates, but this is not the case: some genetic markers are more suited to dating than others."

The study also reports multiple subgroups of the R-M269 group that are very common in different parts of Europe, consistent with expansion of these different groups in each place.

The peopling of Europe and the cautionary tale of Y chromosome lineage R-M269 is published online in the Proceedings of the Royal Society.

For more information please contact Eleanor Cowie, Press and PR Office, on Tel: 0131 650 6514 or Eleanor.Cowie@ed.ac.uk

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6 million years of savanna

2011-08-28T12:37:00.000-07:00

Public release date: 3-Aug-2011
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Contact: Lee Siegel
lee.siegel@utah.edu
801-581-8993
University of Utah

SALT LAKE CITY, Aug. 3, 2011 ? University of Utah scientists used chemical isotopes in ancient soil to measure prehistoric tree cover ? in effect, shade ? and found that grassy, tree-dotted savannas prevailed at most East African sites where human ancestors and their ape relatives evolved during the past 6 million years.

"We've been able to quantify how much shade was available in the geological past," says geochemist Thure Cerling, senior author of a study of the new method in the Thursday, Aug. 4, 2011 issue of the journal Nature. "And it shows there have been open habitats for all of the last 6 million years in the environments in eastern Africa where some of the most significant early human fossils were found."

"Wherever we find human ancestors, we find evidence for open habitats similar to savannas ? much more open and savanna-like than forested," adds Cerling, a University of Utah distinguished professor of geology and geophysics, and biology.

Fossils of early humans and their ancestors and extinct relatives have been found in both wooded and open environments in East Africa. Even 4.3-million-year-old Ardipithecus ? which lived in the woods, according to its discoverers ? had a small component of tropical grasses in its diet, Cerling says.

"The fact it had some means it was going into the savanna, unless it was eating takeout food," he says.

Scientists have spent a century debating the significance of savanna landscape in human evolution, including the development of upright walking, increased brain size and tool use.

Part of the problem has been a fuzzy definition of "savanna," which has been used to describe "virtually everything between completely open grasslands and anything except a dense forest," Cerling says. He adds the most common definition is a fairly open, grassy environment with a lot of scattered trees ? a grassland or wooded grassland.

Open Landscapes throughout the Evolution of Humans and Their Relatives

In the new study, Cerling says he and colleagues developed "a new way to quantify the openness of tropical landscapes. This is the first method to actually quantify the amount of canopy cover, which is the basis for deciding if something is savanna."

Cerling does not dispute that East African savannas became more expansive within the past 2 million years, or that human ancestors and relatives likely spent time in narrow "gallery forests" along river corridors.

But he says the new method shows grasslands and wooded grasslands ? in other words, savannas ? have prevailed for more than 6 million years in the cradle of humanity, with tree cover less than about 40 percent at most sites. By definition, woodland has more than 40 percent tree cover, and a forest has more than 80 percent tree cover.

"In some periods, it was more bushy, and other times it was less bushy," he says. "Hardly anything could have been called a dense forest, but we can show some periods where certain environments were consistently more wooded than others. We find hominins (early humans, pre-humans and chimp and gorilla relatives) in both places. How early hominins partitioned their time between 'more open' and 'more closed' habitats is still an open question."

Cerling says even sparse woody canopy provided hominins with shade, some foods and refuge from predators.

Fossil evidence of hominins ? humans, their ancestors and early relatives such as chimps and gorillas ? date back to 4.3 million years and possibly 6 million years, Cerling says. The new method was used to look for and find savanna up to 7.4 million years ago.

"Currently, many scientists think that before 2 million years ago, things were forested [in East Africa] and savanna conditions have been present only for the past 2 million years," Cerling says. "This study shows that during the development of bipedalism [about 4 million years ago] open conditions were present," even predominant.

Cerling conducted the study with biologists Samuel Andanje and David Kimutai Korir of the Kenya Wildlife Service; geologist Michael Bird of James Cook University, Cairns, Australia; University of Utah graduate students William Mace of geology, Anthony Macharia of geography and Christopher Remien of mathematics; and former Utah geology graduate students Jonathan Wynn of the University of South Florida, Naomi Levin of Johns Hopkins University and Jay Quade of the University of Arizona.

The National Science Foundation and the Leakey Foundation funded the study.

Deducing Prehistoric Tree Cover from Soil Isotopes

The new method was developed by correlating carbon isotope ratios in 3,000 modern soil samples with satellite photos of tree and vegetation cover at 75 tropical sites worldwide ? half in Africa ? representing everything from closed forest to open grassland. That allowed scientists to determine the percent of tree and woody shrub cover millions of years ago based on carbon isotope ratios in fossil soils known as paleosols.

"This study is based on the geological axiom that the present is the key to the past," says Cerling. "We assume soils in the past had similar relationships to vegetation as what we observe today."

The researchers collected soil samples at Kenyan and Ethiopian sites and used published data on soil samples collected by others during the past decade at the other sites throughout the tropics. Modern soil samples came from national parks and reserves and non-agricultural areas so that carbon isotope rations reflected natural vegetation.

The ratio of rare carbon-13 to common carbon-12 in decayed plant material in soils reveals the extent to which the landscape was covered by plants that use what is known as the C3 pathway of photosynthesis versus plants that use C4 photosynthesis.

Trees, shrubs, herbs, forbs and cool-season grasses are C3 plants, which include beans and most vegetables. C4 plants are warm-season or tropical grasses that dominate savannas, and plants called sedges. C4 plants have a higher ratio of carbon-13 than C3 plants.

The isotope composition of fossil soil gives a measure of the total makeup of the ecosystem in terms of how much canopy versus how much open landscape, Cerling says. So in a forest, even soil from open gaps shows the C3 signature because of non-woody C3 plants growing there, while on a savanna, soil from under a C3 tree will show the C4 signature because of grasses growing under the tree.

The Findings: A History of Savanna

Cerling and colleagues used the new method to analyze fossil soils and infer plant cover back to 7.4 million years ago, a period that includes when human ancestors and apes split from a common ancestor.

Their analysis of 1,300 fossil soil samples from sites at or near where human ancestors and their relatives evolved shows that more than 70 percent of the sites had less than 40 percent woody cover, meaning they were wooded grasslands or grasslands. Less than 1 percent of the samples reflected sites where tree cover exceeded 70 percent.

"Therefore, 'closed' forests (more than 80 percent woody cover) represent a very small fraction of the environments represented by these paleosols," the researchers write.

"We conclude there have been open savannas all the time for which we have hominin fossils in the environments where the fossils were found during the past 4.3 million years" ? the oldest fossils now accepted as human ancestors, Cerling says.

The researchers also created vegetation chronologies of the Awash Valley of Ethiopia and the Omo-Turkana Basin of Ethiopia and Kenya ? home to many fossils of human ancestors, including Ardipithecus, Australopithecus, Paranthropus and our own genus, Homo.

They found that during the past 7.4 million years, woody cover ranged from 75 percent (closed woodlands) down to 5 percent or less (open grasslands), but significant areas with woody cover below 40 percent (savanna woodlands to savanna grasslands) were consistently present.

University of Utah Public Relations
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The last 3 million years at a snail's pace

2011-08-28T09:31:00.000-07:00

Public release date: 4-Aug-2011
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Contact: David Garner
david.garner@york.ac.uk
44-019-043-22153
University of York

Scientists at the University of York, using an 'amino acid time capsule', have led the largest ever programme to date the British Quaternary period, stretching back nearly three million years.

It is the first widespread application of refinements of the 40-year-old technique of amino acid geochronology. The refined method, developed at York's BioArCh laboratories, measures the breakdown of a closed system of protein in fossil snail shells, and provides a method of dating archaeological and geological sites.

Britain has an unparalleled studied record of fossil-rich terrestrial sediments from the Quaternary, a period that includes relatively long glacial episodes ? known as the Ice Age --interspersed with shorter 'interglacial' periods where temperatures may have exceeded present day values.

However, too often the interglacial deposits have proved difficult to link to global climatic signals because they are just small isolated exposures, often revealed by quarrying..

Using the new method, known as amino acid racemization, it will be possible to link climatic records from deep sea sediments and ice cores with the responses of plants and animals, including humans, to climate change over the last three million years. The research is published in the latest issue of Nature.

The new method was developed by Dr Kirsty Penkman, of the Department of Chemistry, alongside Prof. Matthew Collins of the Department of Archaeology at York, and measures the the extent of protein degradation in calcareous fossils such as mollusc shells. It is based on the analysis of intra-crystalline amino acids ? the building blocks of protein --preserved in the fossil opercula (the little 'trapdoor' the snail uses to shut itself away inside its shell) of the freshwater gastropod Bithynia. It provides the first single method that is able to accurately date such a wide range of sites over this time period.

Dr Penkman said: "The amino acids are securely preserved within calcium carbonate crystals of the opercula. This crystal cage protects the protein from external environmental factors, so the extent of internal protein degradation allows us to identify the age of the samples. In essence, they are a protein time capsule.

"This framework can be used to tell us in greater detail than ever before how plants and animals reacted to glacial and interglacial periods, and has helped us establish the patterns of human occupation of Britain, supporting the view that these islands were deserted in the Last Interglacial period."

In a close collaboration with palaeontologist Dr. Richard Preece in the Department of Zoology at the University of Cambridge, the study examined a total of 470 fossil remains from 71 sites in the UK and three on continental Europe. The method proved highly reliable with more than 98 per cent of samples yielding useful results, resulting in the largest ever geochronological programme of the British Pleistocene.

Professor Collins said: "When we started this work 11 years ago, we thought it was going to be relatively straightforward to identify a good material for dating, but the first 3 years of research on shells showed that the stability of the mineral itself was vital. The tiny trapdoor of a snail proved to be the key to success."

Dr Preece added: "Luckily, fossil opercula are common in Quaternary sediments around the world, so the new technique can be used to build regional Ice Age chronologies everywhere, giving it enormous international scope".

Vital to the study were the inter-disciplinary collaborations with Quaternary scientists, the core team of which involved researchers at the Department of Geography, University of Durham; Institute of Archaeology and Antiquity, University of Birmingham; Institute of Archaeology, University College London; the Netherlands Centre for Biodiversity, Leiden and the Department of Palaeontology, The Natural History Museum.

The analyses were funded by English Heritage, Natural Environment Research Council and the Wellcome Trust. The research is a contribution to the Ancient Human Occupation of Britain (AHOB) project funded by the Leverhulme Trust.

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6 million years of African savanna

2011-08-28T04:46:00.000-07:00

Public release date: 4-Aug-2011
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Contact: Cheryl Dybas
cdybas@nsf.gov
703-292-7734
National Science Foundation

Scientists using chemical isotopes in ancient soil to measure prehistoric tree cover--in effect, shade--have found that grassy, tree-dotted savannas prevailed at most East African sites where human ancestors and their ape relatives evolved during the past six million years.

"We've been able to quantify how much shade was available in the geological past," says University of Utah geochemist Thure Cerling, lead author of a paper titled "Woody cover and hominin environments in the past 6 million years" on the results in this week's issue of the journal Nature.

"It shows there have been open habitats for the last six million years in the environments in East Africa where some of the most significant early human fossils were found.

"Wherever we find human ancestors, we find evidence for open habitats similar to savannas--much more open and savanna-like than forested."

Scientists have spent a century debating the significance of open, savanna landscape in human evolution, including the development of upright walking, increased brain size and tool use.

Part of the problem has been an imprecise definition of "savanna," which has been used to describe "virtually everything between completely open grasslands and anything except a dense forest," Cerling says.

He adds that the most common usage is a fairly open, grassy environment with many scattered trees--a grassland or wooded grassland.

In the study, Cerling and colleagues developed a new way to quantify the openness of tropical landscapes. This is the first method to quantify the amount of canopy cover, the basis for deciding whether something is savanna.

The National Science Foundation (NSF) and the Leakey Foundation funded the study.

"The development of a paleo-shade proxy for soil temperature and woody cover, and its application to ancient fossil sites, reinforces the long-held theory that the roots of human origins are in the open grassland/savanna environments of East Africa," says H. Richard Lane, program director in NSF's Division of Earth Sciences.

Adds Kaye Reed of NSF's Division of Behavioral and Cognitive Sciences, "These investigators have done an amazing job of collecting modern comparative isotope and soil temperature samples to compare with paleosol [fossil soil] samples from hominin localities. Their newly developed method for calculating 'paleo-shade' is very innovative."

Cerling does not dispute that East African savannas became more expansive within the past two million years, or that human ancestors and relatives likely spent time in narrow "gallery forests" along river corridors.

But he says the new method shows that grasslands and wooded grasslands--savannas--have prevailed for more than six million years in the cradle of humanity, with tree cover less than about 40 percent at most sites.

By definition, woodland has more than 40 percent tree cover; forest has more than 80 percent tree cover.

"In some periods, it was more bushy, and other times it was less bushy," he says.

"Hardly anything could have been called a dense forest, but we can show some periods where certain environments were consistently more wooded than others.

"We find hominins in both places. How early hominins partitioned their time between 'more open' and 'more closed' habitats is still an open question."

Cerling says that even sparse woody canopy provided hominins with shade, some foods and refuge from predators.

Fossil evidence of hominins dates back 4.3 million years and possibly 6 million years, Cerling says. The new method was used to look for and find savanna up to 7.4 million years ago.

"Currently, many scientists think that before 2 million years ago, the region was forested, and that savanna conditions have been present only for the past 2 million years," Cerling says. "This study shows that during the development of bipedalism [about 4 million years ago] open conditions were present, even predominant."

Cerling conducted the study with biologists Samuel Andanje and David Kimutai Korir of the Kenya Wildlife Service; geologist Michael Bird of James Cook University, Cairns, Australia; University of Utah graduate students William Mace, Anthony Macharia and Christopher Remien; and Jonathan Wynn of the University of South Florida, Naomi Levin of Johns Hopkins University and Jay Quade of the University of Arizona.

The new method was developed by correlating carbon isotope ratios in 3,000 modern soil samples with satellite photos of tree and vegetation cover at 75 tropical sites worldwide--half in Africa--representing closed forest to open grassland.

That allowed scientists to determine the percent of tree and woody shrub cover millions of years ago based on carbon isotope ratios in fossil soils known as paleosols.

"This study is based on the geological axiom that the present is the key to the past," says Cerling. "We assume soils in the past had similar relationships to vegetation as what we observe today."

The researchers collected soil samples at Kenyan and Ethiopian sites and used published data on soil samples collected by others during the past decade at sites throughout the tropics.

Modern soil samples came from national parks and reserves and non-agricultural areas so that carbon isotope ratios reflected natural vegetation.

The isotope composition of fossil soil gives a measure of the total makeup of the ecosystem in terms of how much was canopy versus how much was open landscape, Cerling says.

In a forest, even soil from open gaps shows the C3 signature because of non-woody C3 plants growing there, while on a savanna, soil from under a C3 tree will show the C4 signature because of grasses growing under the tree.

Cerling and colleagues used the new method to analyze fossil soils and infer plant cover back to 7.4 million years ago, a period that includes the time when human ancestors and apes split from a common ancestor.

Their analysis of 1,300 fossil soil samples from sites at or near where human ancestors and their relatives evolved shows that more than 70 percent of the sites had less than 40 percent woody cover, meaning they were wooded grasslands or grasslands. Less than one percent of the samples reflected sites where tree cover exceeded 70 percent.

"Therefore, 'closed' forests (more than 80 percent woody cover) represent a very small fraction of the environments represented by these paleosols," the researchers write.

"We conclude there have been open savannas all the time for which we have hominin fossils in the environments where the fossils were found during the past 4.3 million years--the oldest fossils now accepted as human ancestors," Cerling says.

The researchers also created vegetation chronologies of the Awash Valley of Ethiopia and the Omo-Turkana Basin of Ethiopia and Kenya--home to many fossils of human ancestors, including Ardipithecus, Australopithecus, Paranthropus and our own genus, Homo.

They found that during the past 7.4 million years, woody cover ranged from 75 percent (closed woodlands) down to 5 percent or less (open grasslands), but significant areas with woody cover below 50 percent (savanna woodlands to savanna grasslands) were consistently present.

Fossils of early humans and their ancestors and extinct relatives have been found in both wooded and open environments in East Africa.

Even 4.3-million-year-old Ardipithecus--which lived in the woods, according to its discoverers--had a small component of grasses or other C4 plants in its diet, says Cerling.

"The fact that it had this means it was going into the savanna," he says, "unless it was eating takeout food."

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Deadly medication?

2011-08-27T23:50:00.000-07:00

Public release date: 19-Aug-2011
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Contact: Michael Hoeveler-Mueller
aegyptisches-museum@uni-bonn.de
49-228-739-710
University of Bonn

The corpus delicti is a plain flacon from among the possessions of Pharaoh Hatshepsut, who lived around 1450 B.C., which is on exhibit in the permanent collection of the Egyptian Museum of the University of Bonn. For three and a half millennia, the vessel may have held a deadly secret. This is what the Head of the collection, Michael H?veler-M?ller and Dr. Helmut Wiedenfeld from the university's Pharmacology Institute just discovered. After two years of research it is now clear that the flacon did not hold a perfume; instead, it was a kind of skin care lotion or even medication for a monarch suffering from eczema. In addition, the pharmacologists found a strongly carcinogenic substance. Was Hatshepsut killed by her medicine?

When Michael H?veler-M?ller became the curator of the Egyptian Museum of the University of Bonn in 2009, it occurred to him to examine the interior of the vessel that, according to an inscription, belonged to Pharaoh Hatshepsut. Its neck had been blocked with what was generally considered "dirt," but H?veler-M?ller suspected that it might also be the original clay stopper. So possibly, some of the original contents might still be inside. In Dr. Helmut Wiedenfeld from the Pharmacy Institute, he found just the right partner, to get to the bottom of this question and of the flacon.

At the Radiology Clinic of the Bonn Universit?tsklinikum, the flacon was subjected to a CAT scan. Here, the Egyptologist's suspicion was confirmed ? not only was the closure intact, but the vessel also held residue of a dried-up liquid. In the summer of 2009, Professor Dr. Friedrich Bootz from the Klinik und Poliklinik f?r Hals-, Nasen- und Ohrenheilkunde (laryngology, rhinology and otology) of the University of Bonn took samples, using an endoscope.

Too greasy for perfume

This allowed Dr. Wiedenfeld and his team to analyze the old substances for their ingredients. And it became obvious very quickly that what they had found was not dried-up perfume. The mix contained large amounts of palm oil and nutmeg apple oil. "I didn't think anybody would put so much grease on her face," said Dr. Wiedenfeld. "That would make her look as greasy as a plate of ribs." Two additional components clued the pharmacologist in to the actual purpose of the mix, "We found a lot of unsaturated fatty acids that provide relief for people with skin diseases." And this is where the Egyptologist was able to add another piece of the puzzle, "It is indeed known that there were cases of skin disease in Hatshepsut's family." Inflammatory skin diseases such as psoriasis have a largely genetic component.

And the third group of ingredients also points to the fact that this substance was not about providing a nice fragrance, but instead, for fighting a big itch ? the pharmacologists found a lot of hydrocarbons derived from creosote and asphalt. To this day, creams containing creosote are used to treat chronic skin diseases. Due to the potentially carcinogenic effects of some of its ingredients, creosote has meanwhile been banned from cosmetics completely, and medications containing creosote are now prescription-only.

What the pharmacologists detected in Hatshepsut's little bottle was in particular benzo(a)pyrene, a hazardous aromatic hydrocarbon consisting of several carbon rings. "Benzo(a)pyrene is one of the most dangerous carcinogenic substances we know," explained Dr. Wiedenfeld. For example, the risk of contracting lung cancer from cigarette smoke results essentially from this substance.

Did the lotion cause the Pharaoh's death from cancer?

Did Hatshepsut maybe poison herself without knowing it? "There is a lot that speaks for this hypothesis," Dr. Wiedenfeld said. "If you imagine that the Queen had a chronic skin disease and that she found short-term improvement from the salve, she may have exposed herself to a great risk over the years." The Egyptologist also thinks that this is very likely. "We have known for a long time that Hatshepsut had cancer and maybe even died from it," said Michael H?veler-M?ller. "We may now know the actual cause."

But at this point, the Bonn scientists can only surmise how Hatshepsut obtained her lotion. "Egyptian physicians were general practitioners and good surgeons, but they were lousy internists," explained Dr. Wiedenfeld. "It is quite possible that they owe their knowledge of certain medications to their contacts with Persia and India where the healing arts were very advanced even in Antiquity."

For photos regarding this press release, please go to: http://www3.uni-bonn.de/Pressemitteilungen/236-2011

Contact:

Michael H?veler-M?ller
?gyptisches Museum der Universit?t Bonn
Tel.: 0228/73-9710
aegyptisches-museum@uni-bonn.de

Dr. Helmut Wiedenfeld
Pharmazeutisches Institut der Universit?t Bonn
(abroad starting on 22 August)
Email: wiedenfeld@uni-bonn.de

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The Sign of an Advancing Society? An Organized War Effort

2011-08-27T20:05:00.000-07:00

A wave of new research is supporting this second view. Charles Stanish and Abigail Levine, archaeologists at the University of California, Los Angeles, have traced the rise of the pristine states that preceded the Inca empire. The first villages in the region were formed some 3,500 years ago. Over the next 1,000 years, some developed into larger regional centers, spaced about 12 to 15 miles apart. Then, starting around 500 B.C., signs of warfare emerged in the form of trophy heads and depictions of warriors, the two archaeologists report in last week’s Proceedings of the National Academy of Sciences.

One of the regional centers, Taraco, was destroyed in the first century A.D., probably by forces from Pukara, the other principal regional center of the area. Pukara enjoyed its status as a pristine state until about 500, when it was absorbed by Tiwanaku, the principal state on the other side of the Lake Titicaca basin.

A similar process of an early state’s arising from warring chiefdoms has been described in the Oaxaca Valley of Mexico by Kent V. Flannery and Joyce Marcus, archaeologists at the University of Michigan. By 4,500 years ago, there were some 80 villages in the valley. As population increased, a period of intense warfare lasted from 2,450 to 2,000 years ago, culminating in the victory of one town over all the others in the valley and the formation of the Zapotec state.

With the same process now documented in both North and South America, “we are coming closer to having a model for pristine state formation that may have worldwide significance,” Dr. Marcus said. “It also shows that our species, when thrust into almost identical circumstances, behaves in almost identical ways.”

Dr. Stanish believes that warfare was the midwife of the first states that arose in many regions of the world, including Mesopotamia and China as well as the Americas.

The first states, in his view, were not passive affairs driven by forces beyond human control, like climate and geography, as some historians have supposed. Rather, they were shaped by human choice as people sought new forms of cooperation and new institutions for the more complex societies that were developing. Trade was one of these cooperative institutions for consolidating larger-scale groups; warfare was the other.

Warfare may not usually be thought of as a form of cooperation, but organized hostilities between chiefdoms require that within each chiefdom people subordinate their individual self-interest to that of the group.

“Warfare is ultimately not a denial of the human capacity for social cooperation, but merely the most destructive expression of it,” the anthropologist Lawrence H. Keeley writes in his book “War Before Civilization” (Oxford, 1996).

Compared with other species, humans are highly cooperative and altruistic, at least toward members of their own group. Evolutionary biologists have been hard pressed to account for this self-sacrificing behavior, given that an altruist who works for the benefit of others will have less time for his family’s interests and leave fewer surviving children. Genes for altruistic behavior should therefore disappear.

Darwin’s solution to this riddle was that groups of altruists would prevail over less cohesive groups. This implies that natural selection can operate on groups, not just individuals, a thesis that many biologists reject.

But group-level selection is more likely to operate the fiercer the competition is between groups. Samuel Bowles, an economist at the Santa Fe Institute, believes warfare between early human groups was intense, and explains the very slow growth of population prior to 20,000 years ago.

Warfare “may have contributed to the spread of human altruism,” he and his colleague Herbert Gintis write in their new book, “A Cooperative Species”(Princeton, 2011). “We initially recoiled at this unpleasant and surprising conclusion. But the simulations and the data on prehistoric warfare tell a convincing story.”

Archaeology lends some support to the idea. “Groups that successfully organize themselves to raid others will acquire external resources and, in the long run, will be at a selective advantage against groups that are less well organized,” Dr. Stanish and Dr. Levine write of their findings in the Central Andes.

“Both war and trade are sources of outside wealth,” Dr. Stanish said in an interview. The leaders of early states had to keep people working. They relied on religious rituals to organize the labor force and material inducements from war and trade to satisfy the elite.

As the population in a region grew larger and richer, regional chiefdoms would form and start raiding one another for plunder. “Once this kicks in, it sets up a dynamic in which it’s hard to be peaceful,” Dr. Stanish said. “You either organize on a regional level or get killed or absorbed.”

Of the regional chiefdoms that start a war for dominance, all but one will perish before the pristine state is formed. So why not form nonaggression pacts rather than take such a gamble?

Dr. Marcus suggests two reasons. One is that human social skills evolved in the small hunter-gatherer groups in which everyone lived until 15,000 years ago. “When humans try to run larger and more complex societies, with hereditary inequality, they are pushing their sociopolitical skills to the utmost,” Dr. Marcus said.

Another reason is that elites who run chiefly societies “are very aggressive and competitive — they assassinate rivals even when they are siblings or half-siblings,” Dr. Marcus said. “Competitive interaction is one of the most powerful driving forces in evolution, whether biological or social.”

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Ancient whale skulls and directional hearing: A twisted tale

2011-08-27T15:30:00.000-07:00

Public release date: 23-Aug-2011
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Contact: Cheryl Dybas
cdybas@nsf.gov
703-292-7734
National Science Foundation

Skewed skulls may have helped early whales find the direction of sounds in water and are not solely, as previously thought, a later adaptation related to echolocation.

Scientists affiliated with the University of Michigan and funded by the National Science Foundation (NSF) report the finding in a paper published online this week in the journal Proceedings of the National Academy of Sciences.

Asymmetric skulls are a well-known characteristic of the modern whale group known as "odontocetes" or toothed whales.

These whales also have highly modified nasal structures with which they produce high-frequency sounds for echolocation--a sort of biological sonar used to navigate and find food.

The other modern whale group, "mysticetes" or baleen whales, has symmetrical skulls and does not echolocate.

These observations led scientists to believe that archaeocetes--the extinct, ancient whales that gave rise to all modern whales--had symmetrical skulls, and that asymmetry later developed in toothed whales in concert with echolocation, according to H. Richard Lane, program director in NSF's Division of Earth Sciences, which funded the research.

But a new analysis of archaeocete skulls by University of Michigan paleontologist Julia Fahlke and coauthors shows that asymmetry evolved much earlier, as part of a suite of traits linked to directional hearing in water.

"This means that the initial asymmetry in whales is not related to echolocation," said Fahlke, who is working with scientist Philip Gingerich at the University of Michigan Museum of Paleontology.

Fahlke intended to study a completely different aspect of whale evolution: tooth form and function.

"Modern whales don't chew their food," Fahlke said. "Toothed whales just bite it and swallow it, and baleen whales filter-feed. But archaeocetes have characteristic wear patterns on their teeth that show that they've been chewing their food."

By studying those wear patterns, she hoped to piece together how and what early whales ate and how their eating habits changed over time.

She started by studying the skull of Basilosaurus isis, a serpent-like, predatory whale that lived 37 million years ago, using a three-dimensional digital model generated from CT scans of the fossil that were acquired at the University of Michigan Medical School D epartment of Radiology.

The actual skull on which the model was based was asymmetrical, but Fahlke and colleagues at first dismissed the irregularity.

"We thought, like everyone else before us, that this might have happened during burial and fossilization," Fahlke said.

"Under pressure from sediments, fossils often deform."

To correct for the deformation, coauthor Aaron Wood of the University of Florida straightened out the skull in the digital model.

But when Fahlke began working with the "corrected" model, the jaws just didn't fit together right. "Finally it dawned on me: maybe archaeocete skulls really were asymmetrical," she said.

Fahlke began examining archaeocete skulls, and to her astonishment, "they all showed the same kind of asymmetry--a leftward bend when you look at them from the top down," she said.

To study the asymmetry in a more rigorous way, Fahlke and colleagues selected six well-preserved skulls that showed no signs of artificial deformation and measured their deviation from a straight line drawn from snout to back of skull.

For comparison, they made similar measurements of the symmetrical skulls of artiodactyls, the group of terrestrial mammals from which whales evolved.

"Taken together, the six skulls deviate significantly from symmetry," Fahlke said. "Taken individually, four of them deviate significantly."

The other two appear asymmetrical, but their measurements fall within the range of the symmetrical comparative sample.

"This shows that asymmetry existed much earlier than previously thought--before the baleen whales and toothed whales split," Fahlke said.

"This means that the earliest baleen whales must have had asymmetrical skulls, which later became symmetrical."

The authors also show in their paper that archaeocete asymmetry is a three-dimensional torsion, or twist that affects the whole skull, rather than only a two-dimensional bend.

Interestingly, archaeocetes have structures similar to those that are known in toothed whales to function in directional hearing in water: fat bodies in their lower jaws that guide sound waves to the ears, and an area of bone on the outside of each lower jaw thin enough to vibrate and transmit sound waves into the fat body.

This adaptation, along with the acoustic isolation of the ear region from the rest of the skull, appears to have evolved in concert with asymmetry.

The link between asymmetry and directional hearing is not unique to whales, Fahlke said.

"Owls have asymmetrical ear openings, which help them discriminate the rustling of leaves from the rustling of a mouse," Fahlke said.

"Such ability would also be helpful when you're trying to detect prey in the water, so we interpret that the same kind of mechanism was operating for archaeocetes."

In addition to Fahlke, Gingerich and Wood, the paper's authors include Robert Welsh of the University of Michigan Medical School.

Funding was also provided by the Alexander von Humboldt Foundation and the National Geographic Society.

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Adovasio continues underwater search for new frontier

2011-08-27T10:46:00.000-07:00

Public release date: 8-Aug-2011
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Contact: Debbie Morton
dmorton@mercyhurst.edu
814-824-2552
Mercyhurst College

After two years of painstakingly searching for targets, a team of dedicated researchers believes it is within striking distance of uncovering cultural evidence of early human occupation in the now submerged continental shelf of the eastern Gulf of Mexico.

The expedition of the National Oceanic and Atmospheric Administration (NOAA) Office of Ocean Exploration and Research commenced off the Florida coast in the summer of 2008 when a distinguished group of scientists led by Mercyhurst College archaeologists James M. Adovasio and C. Andrew Hemmings identified and mapped buried river channels that could potentially help document the late Pleistocene landscape. In the summer of 2009, they further traced the river systems along whose beaches prehistoric people may have populated and identified raw materials that they may have used in tool-making.

This summer, using sophisticated sub-bottom profiling and side-scan sonar technology, divers will return to these previously identified high-potential locations with an airlift dredge to remove the sediment apron and attempt to excavate archaeological materials. The third installment of the NOAA-funded expedition ? "Exploring the Submerged New World 2011" ? is slated for Aug. 9-18. (The underwater expedition did not proceed in the summer of 2010 due to the BP Oil disaster and related concerns.)

"We understand the prehistoric landscape far better than we did when we started and we have fine-tuned our methods and our technology to put us in the best position to recover enough data both artifactually and in plant and animal remains to get a sense of what life may have been like along these now submerged coastlines," Adovasio said. "We stand at the threshold of discovering lifestyles that may not have a parallel in the archaeological record of North America because they are underwater and never before seen."

Adovasio, best known for his work at the pre-Clovis Meadowcroft Rockshelter in southwestern Pennsylvania that revealed human artifacts dating back 14,000 to 16,000 years, has stood at the vanguard of First Americans studies for decades. The opportunity to extend his reach from the terrestrial to the nautical comes with the recognition that as far back as 22,000 years ago a substantial portion of Earth's water was in the form of glacial ice atop the continents. Today, he said, more than 9 million square miles of what used to be coastlines around the world are underwater and may well represent the first chapter in the peopling of the Americas.

Hemmings, one of the leading Paleoindian underwater archaeologists in North America, is optimistic about this summer's project.

"My feeling is, given a little time to probe the sediments with a dredge, we will find human artifacts," he said.

In addition to Adovasio and Hemmings, the research team includes Dr. Thomas Loebel of the University of Illinois-Chicago Circle and six graduate students from colleges and universities across the U.S., among them Ben Wells and Kimberly Smith, who earned their undergraduate degrees at Mercyhurst. The expedition will also include a NOAA Teacher-at-Sea, Steven Allen.

Besides NOAA, the operation is funded by Mercyhurst College, much of the latter institution's commitment in in-kind services. The research vessel and crew are leased through the University of South Florida.

Adovasio has made multiple presentations on the expedition's progress in the past year, including an address to The Smithsonian Associates, Washington, D.C., as part of a program on "Underwater Settlements: Our New Frontier;" and at the 76th Annual Meeting of the Society for American Archaeology, Sacramento, Calif. Adovasio and Hemmings also presented a paper titled "The Inundated Landscape from Florida's West Coast to the LGM Shoreline: Recent Investigations of Buried Features and Potential Early Human Site Locations" at the Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE) meetings in New Orleans, La.

For more information, please visit: http://mai.mercyhurst.edu/new-world/

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Grateley Primary School Aspirations Day

2011-08-27T06:56:00.000-07:00

On Friday 8th July Victoria Cooper from the Wessex Archaeology Coastal and Marine team visited Grateley Primary School to take part in their Aspirations Day.

Aspirations Day included a wide range of demonstrations and activities, from aikido to wood turning and visits from a helicopter pilot and a local farmer, amongst others. The aim was to inspire pupils to think about new hobbies and interests and was a fantastic opportunity to speak to them about seabed archaeology.

From the very youngest children to the top class, they all loved the opportunity to handle real artefacts. However there was some disappointment that archaeologists don’t dig up dinosaurs! Luckily, the mammoth fossils proved sufficient, although some were a bit squeamish at the prospect of holding the bones and teeth. Everyone had a go at guessing artefacts in the water table and the day ended with a number of inspired young archaeologists in the making.

If you’re interested in learning more about seabed archaeology – check out our Explore the Seafloor website.

Water activity table

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Geological Team Lays Claim to Oldest Known Fossils

2011-08-27T03:51:00.000-07:00

Their assertion, if sustained, confirms the view that life evolved on earth surprisingly soon after the Late Heavy Bombardment, a reign of destruction in which waves of asteroids slammed into the primitive planet, heating the surface to molten rock and boiling the oceans into an incandescent mist. The bombardment, which ended around 3.85 billion years ago, would have sterilized the earth’s surface of any incipient life.

The claim is also a new volley in a long-running conflict over who has found the oldest fossil.

The new microfossils are described in Sunday’s issue of Nature Geoscience by a team led by David Wacey of the University of Western Australia and Martin D. Brasier of the University of Oxford. The fossils were found in sandstone at the base of the Strelley Pool rock formation in Western Australia.

The sandstone, 3.4 billion years ago, was a beach on one of the few islands that had started to appear above the ocean’s surface. Conditions were very different from those of today. The moon orbited far closer to earth, raising huge tides. The atmosphere was full of methane, since plants had not yet evolved to provide oxygen, and greenhouse warming from the methane had heated the oceans to the temperature of a hot bath.

It was in these conditions, the geologists believe, that organisms resembling today’s bacteria lived in the crevices between the pebbles on the beach. Examining thin slices of rock under the microscope, they have found structures that look like living cells, some in clusters that seem to show cell division.

Cell-like structures in ancient rocks can be deceiving — many have turned out to be artifacts formed by nonbiological processes. In this case, the geologists have gathered considerable circumstantial evidence that the structures they see are biological. With an advanced new technique, they have analyzed the composition of very small spots within the cell-like structures. “We can see carbon, sulfur, nitrogen and phosphorus, all within the cell walls,” Dr. Brasier said.

Crystals of fool’s gold, an iron-sulfur mineral, lie next to the microfossils and indicate that the organisms, in the absence of oxygen, fed off sulfur compounds, Dr. Brasier and his colleagues say.

Microfossils — the cell-like structures found in ancient rocks — have become a highly contentious field, both because of the pitfalls in proving that they are truly biological and because the scientific glory of having found the oldest known fossil has led to pitched battles between rival claimants.

The honor of having found the most ancient microfossil has been long been held by J. W. Schopf, a paleobiologist at the University of California, Los Angeles. In 1993, Dr. Schopf reported his discovery of fossils 3.465 billion years old in the Apex chert of the Warrawoona Group in Western Australia, about 20 miles from where the new fossils have been found. Those would be some 65 million years older than the new find, but Dr. Schopf’s claim was thrown in doubt in 2002 when Dr. Brasier attacked his finding, saying the fossils were not biological but just mineral artifacts.

With the new discovery, Dr. Brasier has dropped the second shoe, claiming to find microfossils that are or may be the oldest known, if and when Dr. Schopf’s are knocked out of the running.

The Nature Geoscience article published on Sunday does not claim discovery of the earth’s oldest microfossils. That assertion was made in a press release issued by the University of Oxford, where Dr. Brasier is a professor in the department of earth sciences.

Dr. Brasier said the article submitted to Nature Geoscience had made such a claim, but the reviewers questioned the advisability of doing so, and the senior author, Dr. Wacey, “decided to acquiesce on this particular point.”

Dr. Schopf did not respond to an e-mail seeking his comments. “Bill Schopf still very strongly defends his original claim, and is working to validate it,” said Roger Buick, an earth scientist at the University of Washington.

Dr. Buick said there was no consensus on Dr. Schopf’s microfossils, but that “the majority opinion is that they are probably not biological and probably not as old as claimed.”

The team led by Dr. Wacey and Dr. Brasier has made a “pretty good case,” Dr. Buick said, because the many different analytic techniques they have used “lend credence to the argument in a way that many other previously reported discoveries of particularly ancient microfossils have not.”

Does that mean the new microfossils are the oldest known? “If these are valid, and if we discount the Schopf microfossils, these would be the oldest known, though not by much,” Dr. Buick said.

Rocks older than 3.5 billion years have been so thoroughly cooked as to destroy all cellular structures, but chemical traces of life can still be detected. Chemicals indicative of life have been reported in rocks 3.5 billion years old in the Dresser Formation of Western Australia and, with less certainty, in rocks 3.8 billion years old in Greenland.

“This struggle to be the owner of the world’s oldest microfossils is really not the crux of the battle for understanding the early development of life anymore,” Dr. Buick said.

Andrew H. Knoll, an earth scientist at Harvard, said in a brief e-mail from a Moscow airport that the researchers had not proved their point that the fossils, when alive, fed on sulfur compounds. But he did not take sides on the dispute between Dr. Brasier and Dr. Schopf.

Dr. Buick said: “You’ve got to realize how divisive this microfossil war has been over the last decade. Most people just want it to be over. If claim and counterclaim go back and forth for a decade, it sounds like we don’t know what we’re doing.”

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Subsistence Economies of Indigenous North American Societies: A Handbook

2011-08-26T23:26:00.000-07:00

Public release date: 12-Aug-2011
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Contact: John Gibbons
gibbonsjp@si.edu
Smithsonian

Subsistence Economies of Indigenous North American Societies provides a comprehensive and in-depth documentation of how Native American societies met the challenges of adapting to the varied ecosystems of North America during the past 10,000 years. The contributors identify a number of recurrent themes and questions that have shaped debates regarding the nature of Native American interaction with and impact on their local environments throughout the Holocene.

The volume features full ecosystem coverage of North America, detailing the use of wild plant and animal resources in each of eight broadly defined geographical regions.

The independent domestication of eastern North American plants and the subsequent introduction of domesticated crops, first from Mexico and subsequently from Eurasia, are described in detail, as is the introduction of Eurasian domesticated livestock, and the role of the turkey, the dog, and tobacco in indigenous North American societies.

Drawing from this rich analysis, the volume closes by considering the ways in which and the degree to which Native American societies actively shaped their natural environments.

Subsistence Economies of Indigenous North American Societies is edited by Bruce Smith, curator and senior archaeologist in the Department of Anthropology at the Smithsonian's National Museum of Natural History.

The handbook is published by Smithsonian Institution Scholarly Press.

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Forests absorb one-third of our fossil fuel emissions

2011-08-26T18:48:00.000-07:00

Public release date: 9-Aug-2011
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Contact: Craig Macaulay
Pep.Canadell@csiro.au
61-262-465-631
CSIRO Australia

The world's established forests remove 2.4 billion tonnes of carbon per year from the atmosphere ? equivalent to one third of current annual fossil fuel emissions ? according to new research published today in the journal Science. This is the first time volumes of the greenhouse gas absorbed from the atmosphere by tropical, temperate and boreal forests have been so clearly identified.

"This is really a timely breakthrough with which we can now clearly demonstrate how forests and changes in landscape such as wildfire or forest regrowth impact the removal or release of atmospheric carbon dioxide (CO2)," says CSIRO co-author of the paper: A Large and Persistent Carbon Sink in the World's Forests, Dr Pep Canadell.

"What this research tells us is that forests play a much larger role as carbon sinks as a result of tree growth and forest expansion."

Dr Canadell, who is also the Executive Director of the Global Carbon Project, said the international research team combined data from forest inventories, models and satellites to construct a profile of forests as major regulators of atmospheric CO2.

In addition to the large carbon sink, he said scientists now know that deforestation is responsible for emitting 2.9 billion tonnes of carbon per year ? an exchange that had not been known in the past because of a lack of data. For comparison, total emissions from fossil fuels are currently above eight billion tonnes of carbon per year.Dr Canadell said emissions from deforestation are much larger than previously thought, suggesting that the potential benefits of avoiding deforestation through the United Nations-backed Reduced Emissions from Deforestation and Degradation (REDD) scheme, are much larger than previously appreciated.

The REDD scheme aims to formulate a financial value for the carbon stored in forests.

Dr Canadell said a surprising finding was the large capacity of tropical forest re-growth to remove atmospheric CO2. Regrowth takes place following the end of logging and slash-and-burn land clearing projects. and, to a lesser extent, when new forest plantations are planted.

"We estimate that tropical forest regrowth is removing an average of 1.6 billion tonnes of carbon per year. Unfortunately, some countries have not looked on forest regrowth as a component of REDD, and so are missing a very important opportunity to gain even further climate benefits from the conservation of forests.

"Combining the uptake by established and forest re-growth plus emissions from deforestation, the world's forests have a net effect on atmospheric CO2 equivalent to the removal of 1.1 billion tonnes of carbon every year.

"Carbon exchanges from tropical forests have the highest uncertainties in this analysis and this research has required a concerted effort to refine them to our best knowledge," Dr Canadell said.

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MIT: Oxygen's watery past

2011-08-26T14:16:00.000-07:00

Public release date: 16-Aug-2011
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Contact: Caroline McCall
cmccall5@mit.edu
Massachusetts Institute of Technology

CAMBRIDGE, Mass. -- Today, oxygen takes up a hefty portion of Earth's atmosphere: Life-sustaining O2 molecules make up 21 percent of the air we breathe. However, very early in Earth's history, O2 was a rare ? if not completely absent ? player in the turbulent mix of primordial gases. It wasn't until the "Great Oxidation Event" (GOE), nearly 2.3 billion years ago, when oxygen made any measurable dent in the atmosphere, stimulating the evolution of air-breathing organisms and, ultimately, complex life as we know it today.

Now, new research from MIT suggests O2 may have been made on Earth hundreds of millions of years before its debut in the atmosphere, keeping a low profile in "oxygen oases" in the oceans. The MIT researchers found evidence that tiny aerobic organisms may have evolved to survive on extremely low levels of the gas in these undersea oases.

In laboratory experiments, former MIT graduate student Jacob Waldbauer, working with Professor of Geobiology Roger Summons and Dianne Newman, formerly of MIT's Department of Biology and now at the California Institute of Technology, found that yeast ? an organism that can survive with or without oxygen ? is able to produce key oxygen-dependent compounds, even with only miniscule puffs of the gas.

The findings suggest that early ancestors of yeast could have been similarly resourceful, working with whatever small amounts of O2 may have been circulating in the oceans before the gas was detectable in the atmosphere. The team published its findings last week in the Proceedings of the National Academy of Sciences.

"The time at which oxygen became an integral factor in cellular metabolism was a pivotal point in Earth history," Summons says. "The fact that you could have oxygen-dependent biosynthesis very early on in the Earth's history has significant implications."

The group's results may help reconcile a debate within the earth sciences community: About a decade ago, geochemists encountered sedimentary rocks containing fossil steroids, an essential component of some organisms' cell membranes. Making a single molecule of a sterol, such as cholesterol, from scratch requires at least 10 molecules of O2; since the molecular fossils date back to 300 million years before the GOE, some have interpreted them as the earliest evidence of oxygen's presence on Earth. But because other evidence for the presence of oxygen in rocks of similar age is inconclusive, many geologists have questioned whether the fossilized steroids are indeed proof of early oxygen.

Waldbauer and colleagues suggest that perhaps O2 was in fact present on Earth 300 million years before it spiked in the atmosphere ? just at extremely low concentrations that wouldn't have left much of a trace in the rock record. They reasoned that, even at such low levels, this O2 may have been sufficient to feed aerobic, sterol-producing organisms.

To test their theory, they looked to modern yeast as a model. Yeast naturally uses O2, in combination with sugars, to synthesize ergosterol, its primary sterol. Yeast can also grow without O2, so long as a source of ergosterol is provided. To find the lowest level of O2 yeast can consume, the team set up an experiment to identify the point at which yeast switches from anaerobic to aerobic activity.

Waldbauer grew yeast cells with a mixture of essential ingredients, including ergosterol as well as glucose labeled with carbon-13. They found that, without oxygen present, yeast happily took up sterol from the medium but made none from scratch. When Waldbauer pumped in tiny amounts of oxygen, a switch occurred, and yeast began using O2 in combination with glucose to produce its own sterols. The presence of carbon-13 differentiates the biosynthesized sterol from that acquired from the growth medium.

The scientists found that yeast are able to make steroids using vanishingly small, nanomolar concentrations of O2, supporting the theory that oxygen ? and its producers and consumers ? may have indeed been around long before the gas made an appearance in the atmosphere.

Waldbauer and Summons surmise that oxygen production and consumption may have occurred in the oceans for hundreds of millions of years before the atmosphere saw even a trace of the gas. They say that in all likelihood, cyanobacteria, blue-green algae living at the ocean surface, evolved the ability to produce O2 via sunlight in a process known as oxygenic photosynthesis. But instead of building up in the oceans and then seeping into the atmosphere, O2 may have been rapidly consumed by early aerobic organisms. Large oceanic and atmospheric sinks, such as iron and sulfide spewing out of subsea volcanoes, likely consumed whatever O2 was left over.

"We know all kinds of biology happens without any O2 at all," says Waldbauer, now a postdoc at Caltech. "But it's quite possible there was a vigorous cycle of O2 happening in some places, and other places it might have been completely absent."

Written by Jennifer Chu, MIT News Office

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Archaeologists uncover 3,000-year-old lion adorning citadel gate complex in Turkey

2011-08-26T11:15:00.000-07:00

ScienceDaily (Aug. 9, 2011) — Archaeologists leading the University of Toronto's Tayinat Archaeological Project in southeastern Turkey have unearthed the remains of a monumental gate complex adorned with stone sculptures, including a magnificently carved lion. The gate complex provided access to the citadel of Kunulua, capital of the Neo-Hittite Kingdom of Patina (ca. 950-725 BCE), and is reminiscent of the citadel gate excavated by British archaeologist Sir Leonard Woolley in 1911 at the royal Hittite city of Carchemish.

The Tayinat find provides valuable new insight into the innovative character and cultural sophistication of the diminutive Iron Age states that emerged in the eastern Mediterranean following the collapse of the great civilized powers of the Bronze Age at the end of second millennium BCE.

"The lion is fully intact, approximately 1.3 metres in height and 1.6 metres in length. It is poised in a seated position, with ears back, claws extended and roaring," says Timothy Harrison, professor of near eastern archaeology in the Department of Near and Middle Eastern Civilizations and director of U of T's Tayinat Archaeological Project (TAP). "A second piece found nearby depicts a human figure flanked by lions, which is an iconic Near Eastern cultural motif known as the Master and Animals. It symbolizes the imposition of civilized order over the chaotic forces of the natural world."

"The presence of lions, or sphinxes, and colossal statues astride the Master and Animals motif in the citadel gateways of the Neo-Hittite royal cities of Iron Age Syro-Anatolia continued a Bronze Age Hittite tradition that accentuated their symbolic role as boundary zones, and the role of the king as the divinely appointed guardian, or gatekeeper, of the community," says Harrison. The elaborately decorated gateways served as dynastic parades, legitimizing the power of the ruling elite.

The gate complex appears to have been destroyed following the Assyrian conquest of the site in 738 BCE, when the area was paved over and converted into the central courtyard of an Assyrian sacred precinct.

"The stylistic features of the lion closely resemble those of a double-lion column base found in the 1930s in the entrance to one of the temples that formed the Assyrian sacred precinct," says Harrison. "Whether reused or carved during the Assyrian occupation of the site, these later lion figures clearly belonged to a local Neo-Hittite sculptural tradition that predated the arrival of the Assyrians, and were not the product of Assyrian cultural influence as scholars have long assumed."

TAP is an international project, involving researchers from a dozen countries, and more than 20 universities and research institutes. It operates in close collaboration with the Ministry of Culture of Turkey, and provides research opportunities and training for both graduate and undergraduate students. The project is funded by the Social Sciences and Humanities Research Council of Canada and the Institute for Aegean Prehistory (INSTAP), and receives support from the University of Toronto.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Toronto, via EurekAlert!, a service of AAAS.

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

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'Amino acid time capsule': New way to date the past

2011-08-26T06:42:00.000-07:00

ScienceDaily (Aug. 8, 2011) — Scientists at the University of York, using an 'amino acid time capsule', have led the largest ever programme to date the British Quaternary period, stretching back nearly three million years.

Britain has an unparalleled studied record of fossil-rich terrestrial sediments from the Quaternary, a period that includes relatively long glacial episodes -- known as the Ice Age --interspersed with shorter 'interglacial' periods where temperatures may have exceeded present day values.

However, too often the interglacial deposits have proved difficult to link to global climatic signals because they are just small isolated exposures, often revealed by quarrying..

The new method was developed by Dr Kirsty Penkman, of the Department of Chemistry, alongside Prof. Matthew Collins of the Department of Archaeology at York, and measures the the extent of protein degradation in calcareous fossils such as mollusc shells. It is based on the analysis of intra-crystalline amino acids -- the building blocks of protein --preserved in the fossil opercula (the little 'trapdoor' the snail uses to shut itself away inside its shell) of the freshwater gastropod Bithynia. It provides the first single method that is able to accurately date such a wide range of sites over this time period.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of York.

Journal Reference:

Kirsty E. H. Penkman, Richard C. Preece, David R. Bridgland, David H. Keen, Tom Meijer, Simon A. Parfitt, Tom S. White, Matthew J. Collins. A chronological framework for the British Quaternary based on Bithynia opercula. Nature, 2011; DOI: 10.1038/nature10305

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

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Biological communities studied at historical WWII shipwrecks along North Carolina

2011-08-26T03:06:00.000-07:00

Public release date: 25-Aug-2011
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Contact: Vernon Smith
vernon.smith@noaa.gov
301-713-7248
NOAA Headquarters

In the waters off the North Carolina coast, historically-significant World War II submarines and shipwrecks rest on the seafloor, a testament to a relatively unknown chapter in U.S. history. According to a new NOAA report, the shipwrecks are not only important for their cultural value, but also as habitat for a wide diversity of fishes, invertebrates and algal species. Additionally, due to their unique location within an important area for biological productivity, the shipwrecks are potential sites for examining community change.

In June 2010, scientists conducted biological and ecological investigations on four World War II shipwrecks (Keshena, City of Atlanta, Dixie Arrow, EM Clark), as part of NOAA's Battle of the Atlantic research project. At each shipwreck site, fish community surveys were conducted and benthic photo-quadrants were collected to characterize the mobile conspicuous fish, smaller prey fish, and sessile invertebrate and algal communities. In addition, temperature sensors were placed at all four shipwrecks, as well as an additional shipwreck, the Manuela.

The data, which establishes a baseline condition to use in future assessments, suggest strong differences in both the fish and benthic communities among the surveyed shipwrecks based on ocean depth.

The full National Marine Sanctuaries' Conservation Series report, "Fish and Habitat Community Assessments on North Carolina Shipwrecks: Potential sites for detecting climate change in the Graveyard of the Atlantic," can be viewed here: http://sanctuaries.noaa.gov/science/conservation/pdfs/bota.pdf

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Fossil May Evict Archaeopteryx From Avian Family Tree

2011-08-25T23:31:00.000-07:00

Chinese paleontologists reported in the current issue of the journal Nature that a previously unknown chicken-size 155-million-year-old dinosaur with feathers, named Xiaotingia zhengi, “challenges the centrality of Archaeopteryx in the transition to birds.”

Like so many fossil dinosaurs and other life from the late Jurassic period, Xiaotingia was found in Liaoning Province, a happy hunting ground for paleontologists. The skeleton was embedded in shale, along with the clear impressions of feathers. Scientists who studied the specimen said it was not as striking in appearance as several of the 10 known Archaeopteryx remains, but good enough apparently to contradict conventional wisdom about proto-birds.

The discovery team and other scientists emphasized that the new findings, if confirmed by additional research, would not undermine the prevailing theory that modern birds descended from dinosaurs. The question now is, if not Archaeopteryx, which of many feathered dinosaurs or dinosaurlike birds being found is closest to the first bird? Other assumptions about the early evolution of birds, they said, would also need to be re-evaluated.

Xing Xu and his colleagues at the Chinese Academy of Sciences in Beijing said that their examination of Xiaotingia, in comparison with more recognizably bird skeletons from the same period as well as the 150-million-year-old Archaeopteryx, showed that the new fossils fell short of a place in the avian family. Several of its anatomical traits, like the long and robust forelimbs once thought to be diagnostic of birds, were actually common to a group of dinosaurs known as deinonychosaurs.

Dr. Xu’s team concluded that “the most important result of our analysis” is that the anatomies of the Chinese specimen and Archaeopteryx were remarkably similar, meaning that both belonged to the lineage of the meat-eating deinonychosaurs, not the plant-eating early birds. In short, Archaeopteryx presumably was not an ancestral bird. The recent discovery of a tenth Archaeopteryx specimen “greatly improved our knowledge” of its similarities to the dinosaur group and its differences from birds, the paleontologists said.

Several scientists who were not involved in the research said they were not especially surprised by the findings.

“It may seem heretical to say that Archaeopteryx isn’t a bird, but this idea has surfaced occasionally since as far back as the 1940s,” Lawrence M. Witmer, a paleontologist at Ohio University, wrote in a commentary accompanying the journal article. “Moreover, there has been growing unease about the avian status of Archaeopteryx as, one by one, its ‘avian’ attributes (feathers, wishbone, three-fingered hand) started showing up in non-avian dinosaurs.”

Nor was this report likely to be the last word on the subject. The researchers themselves, among the leading dinosaur specialists in China, acknowledged that their interpretation was sure to be controversial. They conceded that some of their conclusions are “only weakly supported by the available data.” At such an early stage in the dinosaur-bird transition, distinctions among species were often subtle, or “rather messy affairs,” as Dr. Witmer said.

Scientists are expected to take another, deeper look at many feathered fossil animals that have been uncovered in China in the last 15 years. Several of these avian dinosaur species, including Epidexipteryx, Jeholornis and Sapeornis, may then take wing as the new early birds. And relentless fossil hunters are certain to turn up new species.

“This will be frustrating and exciting,” Dr. Witmer said in an interview, noting that — who knows? — the next discovery might tempt scientists to restore Archaeopteryx to its place in the proto-bird flock. “Some of these things may never be entirely conclusive,” he said. “It drives us nuts.”

Since “virtually all our notions about early avian evolution have previously been viewed through the lens of Archaeopteryx,” Dr. Witmer said, “the impact of losing Archaeopteryx from the avian clan is likely to rock the paleontological community for years to come.”

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Connecting Archaeological Data and Grey Literature via Semantic Cross Search

2011-08-25T19:21:00.000-07:00

1. Hypermedia Research Unit, University of Glamorgan, Pontypridd CF37 1DL, Wales, UK. Email: dstudhope@glam.ac.uk
2. Strategic Digital Information Archaeologist, English Heritage

Differing terminology and database structure hinders meaningful cross search of excavation datasets. Matching free text grey literature reports with datasets poses yet more challenges. Conventional search techniques are unable to cross search between archaeological datasets and Web-based grey literature.

Results are reported from two AHRC funded research projects that investigated the use of semantic techniques to link digital archive databases, vocabularies and associated grey literature. STAR (Semantic Technologies for Archaeological Resources) was a collaboration between the University of Glamorgan, Hypermedia Research Unit and English Heritage (EH). The main outcome is a research Demonstrator (available online), which cross searches over excavation datasets from different database schemas, including Raunds Roman, Raunds Prehistoric, Museum of London, Silchester Roman and Stanwick sampling. The system additionally cross searches over an extract of excavation reports from the OASIS index of grey literature, operated by the Archaeology Data Service (ADS).

A conceptual framework provided by the CIDOC Conceptual Reference Model(CRM) integrates the different database structures and the metadata automatically generated from the OASIS reports by natural language processing techniques. The methods employed for extracting semantic RDF representations from the datasets and the information extraction from grey literature are described. The STELLAR project provides freely available tools to reduce the costs of mapping and extracting data to semantic search systems such as the Demonstrator and to linked data representation generally. Detailed use scenarios (and a screen capture video) provide a basis for a discussion of key issues, including cost-benefits, ontology modelling, mapping, terminology control, semantic implementation and information extraction issues.

The scenarios show that semantic interoperability can be achieved by mapping and extracting different datasets and key concepts from OASIS reports to a central RDF based triple store. It is not necessary to expose the full detail of the ontological model; the Demonstrator shows that user interfaces for retrieval (or mapping) systems can be expressed using familiar archaeological concepts. Working with the CRM-EH archaeological extension of the CIDOC CRM ontology allows specific archaeological queries, while permitting interoperability at the more general CRM level, potentially extending to other areas of cultural heritage. The ability to connect published datasets with the hitherto under-utilised grey literature holds potential for meta studies, where aggregate patterns can be compared and hypotheses for future detailed investigation uncovered. Connecting the interpretation with the underlying context data via the semantic model facilitates the revisiting of previous interpretations by third parties, the possibility of juxtaposing parallel interpretations, or exposing the data to new research questions.

The STAR and STELLAR projects were supported by the Arts and Humanities Research Council [grant numbers AH/D001528/1, AH/H037357/1].

This article will appeal to: those interested in the archiving and reuse of digital excavation data, grey literature, the integration and comparison of excavation datasetsKeywords: archive; grey literature; semantic interoperability; semantic search; cross search; ontology; thesaurus; natural language processing; CIDOC-CRM; CRM-EH; SKOSFind more publications on interoperability in the British and Irish Archaeological Bibliography (BIAB)

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Archaeologists uncover 3,000-year-old lion adorning citadel gate complex in Turkey

2011-08-25T15:17:00.000-07:00

Public release date: 9-Aug-2011
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Contact: Sean Bettam
s.bettam@utoronto.ca
416-946-7950
University of Toronto

TORONTO, ON ? Archaeologists leading the University of Toronto's Tayinat Archaeological Project in southeastern Turkey have unearthed the remains of a monumental gate complex adorned with stone sculptures, including a magnificently carved lion. The gate complex provided access to the citadel of Kunulua, capital of the Neo-Hittite Kingdom of Patina (ca. 950-725 BCE), and is reminiscent of the citadel gate excavated by British archaeologist Sir Leonard Woolley in 1911 at the royal Hittite city of Carchemish.

MEDIA CONTACTS:

Timothy P. Harrison
Department of Near and Middle Civilizations
University of Toronto
+90 536-589-2443
416-978-6600
tim.harrison@utoronto.ca

Sean Bettam
Communications, Faculty of Arts & Science
University of Toronto
416-946-7950
s.bettam@utoronto.ca

Jessica Lewis
Communications, Faculty of Arts & Science
University of Toronto
416-978-8887
jessica.lewis@utoronto.ca

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