The 500 million years ocean history

Brachiopod Paraspirifer bownockeri from the Middle Devonian of Ohio (USA); Width: 5.6 cm. Picture: U. Jansen, Senckenberg Museum, Frankfurt am Main.

GEOMAR coordinates European research and education project BASE-LiNE Earth
02.03.2015 / Kiel. As the history of the oceans can be reconstructed in the past 500 million based on calcareous shells of fossil marine life, busy to date with the research project BASE-LiNE Earth. At the same time it enables talented young scientists and scientists a doctorate in an international research environment. The European Union supports the at GEOMAR Helmholtz Centre for Ocean Research Kiel coordinated project with a total of 3.8 million euros.

Almost all life on earth would be extinct - and that at least five times in the past 500 million years. The environmental changes that have each led to the mass extinction, the oceans play an important role in almost all cases. How did it happen that was phased so hostile to life as a life-giving force sea? And why have some species still survive? These are fundamental questions that will be examined in the next three years as part of the European research project BASE-LiNE Earth with innovative technologies and methods. In addition to answering the research questions BASE LiNE Earth serves as the training of talented young scholars and scientists who are recruited by means of a demanding selection process from all over the world and doctorate within the scope of the project. 

The EU promotes the GEOMAR Helmholtz Centre for Ocean Research Kiel coordinated project under a Marie Skłodowska-Curie Action in Horizon2020-Pogramm with a total of 3.8 million euros. The challenge for the future BASE-LiNE Earth-doctoral students, is to provide information to gain from distant epochs of earth's history. "When historians want to know about events 100 or 200 years ago, they visit libraries or archives where there is written evidence from these times," says project coordinator Prof. Dr. Anton Eisenhauer from GEOMAR. "We also use archives. 
However, they see something different. It is, for example, the calcareous shells of fossil brachiopods in which the relevant data on the chemical history of ocean water are stored reliably, "explains the Kiel geochemist on. 

The information is in the calcite shells of course not writing before, but encrypted in the chemical and mineralogical composition. "If we precise the ratios of elements such as strontium, magnesium, boron, or measure of the isotopic to each other, we can decrypt the information," says Professor Eisenhauer.

This then the age of the shell, as well as the chemical composition of the previous ocean and prevailing environmental conditions such as water temperature and the acidity of the water can be reconstructed. We know, for example, know that during the greatest mass extinction 251 million years ago, the ocean contained no oxygen and was acidified to a large extent. 

"This is similar to some scenarios that we expect for the future of our ocean," explains Professor Eisenhauer. Model calculations are carried out within the framework of the project should show how far the former changes in the environment are transferable to the present day. The challenge is to gain this information and to make it usable. In collaboration with industry partners modern analytical methods for obtaining information in cooperation with business partners in this area in the context of BASE-LiNE Earth therefore be generated and developed. The project involves a total of 21 scientific institutions from eight European countries and partners from Canada, Israel, Palestine and Australia involved. 15 PhD positions will announce the project this spring, two of them for the GEOMAR in Kiel. 

The Integrated School of Ocean Sciences (ISOS) provides at the University of Kiel for a comprehensive training program in which the scholars not only pursue their academic goals, but also learn more professional qualifications, skills and interact with each other.  In the coming years, the parties want to do their topic also by means of exhibitions and school supplies to a wider audience. "Of course we also bind the doctoral students, which thus also learn to communicate their work understandable," says the project coordinator. For more information on the project website www.baseline-earth.eu.

Source: Geomar

A Long dry spell doomed Mexican city 1,000 years ago

Ruins of the city of Cantona in the Mexican state of Puebla, with the mountain Cerro Pizarro in the background. The city was abandoned almost 1,000 years ago, probably as a result of a prolonged dry spell. (Ines Urdaneta image courtesy of Wikimedia Commons.)

A UC Berkeley study sheds new light on this question, providing evidence that a prolonged period of below-average rainfall was partly responsible for the abandonment of one such city, Cantona, between A.D. 900 and A.D. 1050.

At its peak, Cantona, located in a dry, volcanic basin (La Cuenca Oriental) east of today’s Mexico City, was one of the largest cities in the New World, with 90,000 inhabitants. The area was a major source of obsidian, and the city may have played a military role alongside an important trade route from the Veracruz coast into the highlands.

To assess the climate in that area before and after Cantona’s collapse, UC Berkeley geographers analyzed sediment cores from a lake located 20 miles south of the former city. They found evidence of a 650-year period of frequent droughts that extended from around A.D. 500 to about A.D. 1150. This was part of a long-term drying trend in highland Mexico that started 2,200 years ago, around 200 B.C. The climate became wetter again in about A.D. 1300, just prior to the rise of the Aztec empire.

“The decline of Cantona occurred during this dry interval, and we conclude that climate change probably played a role, at least towards the end of the city’s existence,” said lead author Tripti Bhattacharya, a UC Berkeley graduate student.

Surprisingly, the population of Cantona increased during the early part of the dry period, perhaps because of political upheaval elsewhere that increased the importance of the heavily fortified city, she said. Teotihuacan, less than 100 miles to the west, was in decline at the time, also possibly because of more frequent droughts. 

Lake Aljojuca, Mexico
The maar lake Aljojuca, 20 miles south of Cantona, yielded sediments that recorded a lengthy series of droughts between A.D. 500 and 1150. (Tripti Bhattacharya photo)

“In a sense the area became important because of the increased frequency of drought,” said UC Berkeley associate professor of geography Roger Byrne. “But when the droughts continued on such a scale, the subsistence base for the whole area changed and people just had to leave. The city was abandoned.”

Bhattacharya, Byrne and their colleagues report their findings in an article appearing this week in the early edition of the journal Proceedings of the National Academy of Sciences. The UC Berkeley researchers analyzed lake cores provided by scientists at the National Autonomous University of Mexico in Juriquilla, Querétaro, Mexico and the German Research Centre for Geosciences in Potsdam, Germany.

Political upheaval and climate change

Byrne emphasized that the area’s typical monsoon weather with wet summers and dry winters did not stop, but was interrupted by frequent short-term droughts, no doubt affecting crops and water supplies. Today the area is close to the northern limit of maize production without irrigation, and would have been particularly vulnerable to drier conditions, he said.

Byrne, a member of the Berkeley Initiative on Global Change Biology (BiGCB) and curator of fossil pollen in the Museum of Paleontology, has studied sediment cores from many lakes in Mexico and California, and is particularly interested in possible links between climate change and human activities.

Nearly 20 years ago, he learned of Cantona and traveled with students to the areas three times to obtain cores from lakes near the site, most of which are maar lakes created by magma explosions. They are deep and often contain undisturbed and regularly layered sediments ideal for chronological studies.

Tripti Bhattacharya
Tripti Bhattacharya analyzed carbonates in lake sediments to explore the climate history of the Cuenca Oriental east of Mexico City. (Ellie Broadman photo)

German colleagues cored this particular lake, Aljojuca, in 2007, and Bhattacharya traveled to Potsdam to collect sediment samples. Oxygen isotope ratios in carbonate sediments are correlated with the ratio of precipitation to evaporation and thus indicate aridity. Organic material in the sediments was used for accelerator mass spectroscopy carbon-14 dating.

“We can show that both the growth and decline of the site took place during a time period of frequent drought, which forces us to think in more nuanced ways about how political and social factors interact with environmental factors to cause social and cultural change,” Bhattacharya said. “That makes the study particularly interesting.”

Bhattacharya noted that more studies are necessary to reconstruct the prehistoric climate of highland Mexico. Such studies could reveal the causes of prehistoric climatic change and whether they were similar to the factors that regulate the region’s climate today, such as the El Niño/Southern Oscillation.

Co-authors include Harald Böhnel and Kurt Wogau of UNAM, Juriquilla; Ulrike Kienel of the German Research Center for Geosciences in Potsdam; B. Lynn Ingram of UC Berkeley; and Susan Zimmerman of Lawrence Livermore National Laboratory. The work was funded by the National Science Foundation.

Source: UC Berkeley

Researcher uncovers surprising cause of the demise of Easter Island indigenous population

Easter Island Credit: Yale

A new paper by a team of researchers including a Virginia Commonwealth University anthropology professor sheds new light on what led to the downfall of the indigenous population of Easter Island — also known as Rapa Nui — prior to European contact in 1722.

The study, "Variation in Rapa Nui (Easter Island) Land Use Indicates Production and Population Peaks Prior to European Contact," published in the Proceedings of the National Academy of Sciences, found that the population's demise likely had more to do with pre-existing environmental conditions than with environmental degradation by the indigenous people.

Christopher Stevenson, Ph.D., an assistant professor of anthropology in the School of World Studies in the College of Humanities and Sciences, recently discussed his team's findings with VCU News.

Your paper explores what led to the collapse of the prehistoric population of Rapa Nui. What did you conclude?

Our paper evaluates a longstanding debate and examines whether the prehistoric population of Rapa Nui experienced a significant islandwide demographic collapse prior to European contact in A.D. 1722. We have used dates from hydrated obsidian artifacts recovered from habitation sites as a proxy for land use over time. The analysis suggests region-specific dynamics that include abandonment of western coast and interior locations. These temporal land-use patterns correlate with rainfall variation and soil quality. The environmental stresses are regionally specific rather than islandwide. Significant erosion around the entire island generated by deforestation has been hypothesized by other researchers as a cause for economic failure. This does not hold up to scrutiny.

How would you characterize the significance of your findings?

This analysis demonstrates that the concept of a sudden "collapse" is a misleading characterization of prehistoric human population dynamics. As a result, we see our approach as useful in the study of other prehistoric societies for which a very rapid demographic collapse has been proposed in prehistory.

Although small, islands can be complex ecosystems that are structured by climatic variation and underlying geology. Human activities are constrained by these parameters and can even cause the ecosystem conditions to change appreciably through their manipulation of the landscape.

Were you surprised by what you found? In what ways?

The results of our research were really quite surprising to our team. Indeed, in the past we’ve published articles about how there was little evidence for pre-European contact societal collapse. When we proposed the [National Science Foundation-funded] project we were expecting that we would gather data supporting the notion that change did not occur until after European contact. In contrast our research suggests that significant changes in land use occurred prior to European contact. The connection between those changes in land use and notions of environmental degradation and subsequent societal collapse are limited.

There is no evidence that massive physical erosion took place on Rapa Nui before European contact and it is unlikely that physical erosion caused productivity decline and societal collapse. While we do not have direct population data, it is clear that people were reacting to regional environmental variation on the island before they were devastated by the introduction of European diseases and other historic processes. In short, our research does not support the suggestion that societal collapse occurred prior to European contact due to physical erosion and productivity decline, but it does indicate that use of less optimal environmental regions changed prior to European contact.

What did your research methodology entail?

We used a method called obsidian hydration dating to date the human creation of volcanic glass tools found at habitation sites. These dates were a proxy for the relative number of people on the island throughout prehistory. We also used an analysis of soil nutrients to look at the fertility of various landforms (e.g., coastal vs. upland) at different elevations up to 500 meters above sea level.

You've written several books on Rapa Nui. What led to your interest in this topic?

This is a continuation of my interest in looking at the development of agricultural systems in small island societies and how that impacts social and economic decisions made in prehistory.

What will you be working on next?

We will be applying some of the same concepts to the Canary Island agricultural systems which have a much higher diversity of geological ages and climatic conditions.

Source: Vcu

Skull sheds light on human-Neanderthal relationship

Retrieved from a cave in northern Israel, the partial skull provides the first evidence that Homo sapiens inhabited that region at the same time as Neanderthals. (Reuters: Nikola Solic)

A partial skull, found in a cave in Israel, is shedding light on the pivotal moment in early human history when our species left Africa and encountered our close cousins the Neanderthals.

Anthropologist Israel Hershkovitz, from Tel Aviv University, called the skull "an important piece of the puzzle of the big story of human evolution."

The findings of the research, led by Hershkovitz, are published today in the journal Nature.

The upper part of the skull - the domed portion without the face or jaws - was unearthed in Manot Cave in Israel's Western Galilee.

Scientific dating techniques determined the skull was about 55,000 years old, a time period when members of our species were thought to have been marching out of Africa,

The researchers say characteristics of the skull suggest the individual was closely related to the first Homo sapiens populations that later colonized Europe.

They also say the skull provides the first evidence that Homo sapiens inhabited that region at the same time as Neanderthals, our closest extinct human relative.

Previous genetic evidence suggests our species and Neanderthals interbred around the time the skull is dated to, with all people of Eurasian ancestry still retaining a small amount of Neanderthal DNA as a result.

"It is the first direct fossil evidence that modern humans and Neanderthals inhabited the same area at the same time," says palaeontologist Bruce Latimer of Case Western Reserve University in Cleveland, another of the researchers.

"The co-existence of these two populations in a confined geographic region at the same time that genetic models predict interbreeding promotes the notion that interbreeding may have occurred in the Levant region," Hershkovitz says.

The robust, large-browed Neanderthals prospered across Europe and Asia from about 350,000 to 40,000 years ago, going extinct sometime after Homo sapiens arrived.

Scientists say our species first appeared about 200,000 years ago in Africa and later migrated outwards. The cave is located along the sole land route for ancient humans to take from Africa into the Middle East, Asia and Europe.

Latimer says he suspects the skull belonged to a woman, although the researchers could not say definitively.

The cave, sealed off for 30,000 years, was discovered in 2008 during sewage line construction work. Hunting tools, perforated seashells perhaps used ornamentally and animal bones have been excavated from the cave, along with further human remains.

Source: ABC

First study of 'Golden Age' mandolins unlocks secrets of their beauty

Mandolins made by G. Filano 1765 (a), A. Vinaccia 1785 (b), G.B. Fabricatore 1789 (c) and G. Gagliano 1799 (d). Credit: Image courtesy of Springer Science+Business Media

Analyzing varnishes and decorations could provide a new way to identify mandolin "Old Masters."

Some of the most elaborately decorated instruments in history were produced in 18th century Naples. The materials for varnishes and decorations used by individual mandolin masters, honed for wealthy clients in the ancient city's labyrinthine artisan quarter, have been kept secret for over 200 years. Details are disclosed for the first time by Tommaso Rovetta from the Università degli Studi di Pavia and colleagues at the Laboratorio Arvedi Research Group in Springer's journal Applied Physics A -- Materials Science & Processing.

Italian conservation scientists studied ten instruments from some of the most important dynasties of the "Golden Age" of Neapolitan mandolins. Advanced high-resolution imaging techniques shed light on some of the most jealously guarded decorative secrets and could provide a new way to accurately identify mandolins from specific workshops.

The Neapolitan mandolin was set apart by the deeper bowl of its body, producing a more resonant sound heard in works by Beethoven and Verdi. The style was developed by the Vinaccia family and adopted by other leading luthiers such as the Filano, Fabricatore and Gagliano families.

The scientists obtained mandolins from each of these makers courtesy of the National Museum of Musical Instruments in Rome and a private collector. Given their rarity and excellent state of conservation, only microscopic samples could be analysed from already-damaged areas. Nevertheless, the team was able to see that different workshops used different techniques and materials to achieve the same aesthetic effect.

"For mandolins of unknown origin, our results could represent a new way to identify where they were made and therefore their historic and economic value," says Tommaso Rovetta.

In particular, the resin used between patterns of pearl, ivory, bone or possibly horn around the sound hole contain a mixture unique to each workshop. Shellac, a resin from the lac beetle popular today in nail varnish, seems to be the only substance which formed a common base to which pigments and minerals were added. In a 1796 Fabricatore, a mineral found only in the volcanic lavas of Mount Vesuvius was detected. The mixtures in Vinaccia instruments were particularly complex and the scientists were surprised to find the fossilised remains of diatoms, a type of algae.

"We assume there were intense exchanges of technical know-how between masters and their apprentices but, with no written records, this knowledge was taken to the grave," says Rovetta. "We hope the rediscovery of ancient recipes will provide inspiration to today's luthiers."

Source: Springer Science+Business Media

Viking fortress discovery: Archaeological dating results

Two carbon-14 dating results have removed all doubt regarding the authenticity of the Viking fortress.
Credit: Image courtesy of Aarhus University

In September 2014, archaeologists from the Danish Castle Centre and Aarhus University announced the discovery of a Viking fortress in a field belonging to Vallø Manor, located west of Køge on the east coast of Sealand. This was the first discovery of its kind in Denmark in over 60 years. Since then, archaeologists have been waiting impatiently for the results of the dating of the fortress. Now the first results are available, and they will be presented at a seminar at Aarhus University on 18 November.

"When the discovery was published back in September, we were certain that we had found a Viking ring fortress, but since then there have been intense discussions online and amongst archaeologists about whether we were right. Now we know without doubt that we have found a fortress from the 10th century," says archaeologist Nanna Holm, curator of the Danish Castle Centre.

Two carbon-14 dating results have removed all doubt regarding the authenticity of the Viking fortress. The carbon-14 dating was performed by the AMS 14C Dating Centre at the Department of Physics and Astronomy at Aarhus University in close collaboration with Accium BioSciences' laboratories in Seattle.

"The two samples were both taken from the outermost tree rings of charred logs that were found in the northern gateway of the fortress. The results of the two samples are almost identical: The fortress was built in the period between the year 900 and the beginning of the 11th century," explains Marie Kanstrup, an employee at the AMS 14C Dating Centre at the Department of Physics and Astronomy, Aarhus University.

Dating is important in determining the role of the fortress in the history of the Viking age

Søren Sindbæk, a professor of medieval archaeology at Aarhus University, explains that archaeologists are still working to date the fortress more precisely.
"We would like to determine a specific year. The carbon-14 method can't provide that, but we are working on different methods that can help us date the fortress even more precisely."

Dating the fortress will be an important step towards understanding its role in the history of the Viking age.

"We can't say whether or not it's Harald Bluetooth's fortress yet, but now that we've dated it to the 10th century, the trail is getting hotter. The things we've discovered about the fortress during the excavations all point in the same direction. We already know that there's a good chance that we'll find conclusive evidence next year," says Sindbæk.

A structure meant to symbolise power

Even though the excavations have closed for this year, the finds bode well for future efforts. The archaeologists' investigations have also revealed that the Viking fortress was built right next to the open sea.

"The excavation showed that there was a basin of fresh or brackish water right next to one side of the fortress -- presumably a quite narrow inlet leading out to Køge Bay. When the fortress was built, hundreds of tonnes of the heavy clay subsoil would have had to have been dug out into the sea basin," explains Nanna Holm.

According to Nanna Holm, this work was undertaken for no other reason than to give the fortress an impressive location. The structure was meant to signal power.

The same master builder may be responsible

The excavation has also shown that the construction of the fortress is closely related to other Viking fortresses such as Fyrkat near Hobro, Aggersborg near the Limfjord and Trelleborg near Slagelse. These fortresses were undoubtedly built during the reign of Harald Bluetooth, and still more evidence suggests that Borgring, as the fortress has been named, might have belonged to the same building programme.

"There are a lot of similar details in these structures. And it's been wonderful to see the same things coming to light at Borgring. In addition to the structure of the rampart and the gates, we have also found traces of a street with wood paving running along the inside of the rampart -- just like in Fyrkat, Aggersborg and Trelleborg. The most striking thing, however, is the measurements of the fortress. The rampart of Borgring is 10.6 metres wide. That is exactly the same width as the rampart of Fyrkat. So it's hard to avoid the sense that the same master builder was responsible," says Sindbæk.

Source: Aarhus University

Findings at viking archaeological site show power trumping practicality

Baylor archeologist Davide Zori and assistant at Viking farmstead. Credit: Image courtesy of Baylor University

Vikings are known for raiding and trading, but those who settled in Iceland centuries ago spent more time producing and consuming booze and beef -- in part to gain political clout in a place very different from their Scandinavian homeland, says a Baylor University archaeologist.

The seafaring warriors wanted to sustain the "big man" society of Scandinavia -- a political economy in which chieftains hosted huge feasts of beer and beef served in great halls, says Davide Zori, Ph.D., a Denmark native and archeological field director in Iceland, who conducted National Science Foundation-funded research in archeology and medieval Viking literature.
But instead, what Zori and his team discovered is what happened when the Vikings spent too long living too high on the hog -- or, in this case, the bovine. 

"It was somewhat like the barbecue here. You wanted a big steak on the grill," said Zori, assistant professor in the Baylor Interdisciplinary Core. He co-edited the book Viking Archaeology in Iceland: Mosfell Archaelogical Project with Jesse Byock, Ph.D., professor of Old Norse and medieval Scandinavian studies at the University of California, Los Angeles.

"It made it really showy -- if you could keep it up." The Viking chieftains used such wealth and cultural displays to flex political muscle with equals or rivals -- plus to cement good relations with local laborers, Zori said.

Zori and Byock's team excavated a farmstead called Hrísbrú in Iceland's Mosfell Valley. The farm -- inhabited by some of the most famous Vikings of the Icelandic sagas -- included a chieftain's longhouse nearly 100 feet long with a "feast-worthy" great hall, a church and a cemetery of 26 graves indicating a mix of pagan and Christian traditions. Males sometimes were buried with ship remnants rather than in the simpler Christian manner of leaving earthly possessions behind.

Carbon dating and studies of volcanic layers indicate the longhouse was built in the late ninth or early 10th century and abandoned by the 11th. The archeological team uncovered 38 layers of floor ash, including refuse dumped atop the abandoned house, also discovering bones, barley seeds and valuable glass beads imported from Asia. "By applying anthropology and medieval texts, we can excavate and compare," Zori said.

Viking sagas, first written in the 13th century and based on oral accounts, included such details as where people sat at feasts, "which shows your ranking . . . These texts read almost like novels. They're incredible sources. They talk about daily life," Zori said.

"Yes, the Vikings may have put axes to one another's heads -- but these accounts also describe milking cows."

High Times and Hard Times

When the Vikings arrived in uninhabited Iceland, they found forested lowlands, ample pastures and sheltered sea inlets. Excavations show that choice cattle were selected for feasts, with ritual slaughter and display of skulls, according to research published by Zori and others in the journal Antiquity. Barley seeds unearthed from floors or refuse heaps indicate barley consumption, and pollen studies demonstrate barley cultivation. Barley could have been used for bread or porridge, but beer's social value makes it very likely barley was used mainly to produce alcohol, Zori said.

Over centuries, as temperatures in the North Atlantic dropped during the "Little Ice Age," being a lavish host got tougher. "Nine months of winter -- and three months that are only a little less than winter," Zori said.

While sheep could find food free range most of the year and were suited for cold, prized cattle had to be kept indoors in large barns during the winter. Savvy supply-and-demand reckoning was crucial to be sure the food lasted -- both for cattle and humans -- and could be preserved.

"They had to decide how many to slaughter and store," Zori said. "They didn't have salt, so they had to use big vats of curdled milk as a preservative." As the landscape changed due to erosion, climate shifts and cleared forests, it became harder to rear larger numbers of cattle.

High-status households also struggled to grow enough grain for beer-making, based on historical accounts and confirmed by a growing body of archeological data. With a shorter growing season and colder climate than in their homelands, Icelandic Vikings would have needed more laborers to improve the soil -- and as the chieftains' power waned, they would have had trouble attracting workers. As barley cultivation stopped, the local chieftains are no longer mentioned in the Viking sagas.

Changing Directions

"You can see in the archeological evidence that they adjusted their strategy and gave it up eventually," Zori said. "It got harder and harder to keep up that showiness -- and when that collapsed, you didn't have that power, that beer and big slabs of beef to show off."

When barley was abandoned, the pollen record shows native grasses for grazing increased. Archeological findings show that the proportion of cattle to sheep bones declined, as Hrísbrú residents shifted to more practical, less laborious sheep-herding.

"You wonder what came first for the chieftains at Hrísbrú: Were they no longer powerful and didn't need barley and beef? Or could they just not keep it up and so they lost power? I favor the second explanation," Zori said.

"What we're doing now is to let the archaeology speak, both for itself and for proof to verify (the texts)," he said. "Investigating politics breathes life into it, instead of just saying, 'Here are three rocks.' You can ask deeper questions."
Zori argues that Viking chieftains' drive to produce expensive beef and beer caused them to put their political aspirations above the greater good of the community.

"Maybe we don't need the Vikings to prove this," he said. "But it shows you that politics can become more important than creating a productive society."

Source: Baylor University

Major Viking hall identified in Sweden

Using ground-penetrating radar. Credit: Martin Rundkvist

A Viking feasting hall measuring almost 50 metres in length has been identified near Vadstena in Sweden. Archaeologists from Stockholm University and Umeå University used ground-penetrating radar, a non-invasive geophysical method, to locate and map the house foundation. The study was published today in the journal Archaeological Prospection.

The Aska barrow, where the hall has been found, was long seen as a burial mound. But archaeologists have now revealed that it is a foundation platform for a large building, most likely dating from the Viking Period. The hall was probably the home of a royal family whose rich graves have previously been excavated nearby.

"Parallels are known from several of the era's elite sites, such as Fornsigtuna near Stockholm and Lejre near Roskilde. The closest similarities are however seen in a recently excavated feasting hall at Old Uppsala near Stockholm. Such close correspondences suggest intensive communication between the two sites," says Martin Rundkvist of Umeå University

The building was about 14 metres wide and was equipped with double walls and four entrances. The measurements also indicate a large fireplace at the centre of the floor.

"Our investigation demonstrates that non-invasive geophysical measurements can be powerful tools for studying similar building foundations elsewhere. They even allow scholars to estimate the date of a building without any expensive excavations," says Andreas Viberg of the Archaeological Research Laboratory at Stockholm University who directed the fieldwork.

Source: Stockholm University

Archaeologists reveal layout of medieval city at Old Sarum

Old Sarum -- aerial photo. Credit: Image courtesy of University of Southampton

Archaeologists from the University of Southampton have revealed for the first time the plan of a network of buildings in a once thriving medieval city at the historic site of Old Sarum, near Salisbury.

A research team of students and academics carried out a geophysical survey of the ancient monument, scanning ground at the site with state-of-the-art equipment to map the remains of buried structures. They concentrated their survey around the inner and outer baileys of what was once a fortification, with its origins in the Iron Age and the Roman conquest.1

Their investigations reveal the layout of a settlement including structures from the late 11th century, contemporary with the construction of a cathedral and castle. The city was inhabited for over 300 years, but declined in the 13th century with the rise of New Sarum (Salisbury).

The project findings mainly concentrate on the medieval period and highlight:

* A series of massive structures along the southern edge of the outer bailey defensive wall, perhaps suggesting large buildings of a defensive nature.
* An open area of ground behind these large structures, perhaps for mustering resources or people, or as part of a circular route through the city..
* Residential areas in the south east and south west quadrants of the outer bailey alongside the inner bailey ditch.
* Evidence of deposits indicating industrial features, such as kilns or furnaces.
* Features suggesting quarrying at the site after the 1300s and following the city's decline -- indicating a later period of habitation at the site..

Archaeologist Kristian Strutt, Experimental Officer and Director of Archaeological Prospection Services at the University of Southampton, says: "Archaeologists and historians have known for centuries that there was a medieval city at Old Sarum, but until now there has been no proper plan of the site.

"Our survey shows where individual buildings are located and from this we can piece together a detailed picture of the urban plan within the city walls."

The research was conducted as part of the Old Sarum and Stratford-Sub-Castle Archaeological Survey Project, directed by Kristian Strutt and fellow Southampton archaeologists Timothy Sly and Dominic Barker. Old Sarum is under the custodianship of English Heritage, who kindly granted permission for the investigation to take place.

Heather Sebire, Property Curator at English Heritage, comments: "Having the team of archaeologists on site over the summer gave our visitors a chance to find out more about how important historic landscapes are surveyed. The use of modern, non-invasive surveying is a great start to further research at Old Sarum.

"From this work we can surmise much about the site's past and, whilst we can't conclusively date the findings, it adds a new layer to Old Sarum's story. We welcome the chance to find out more about our sites, and look forward to exploring ideas for further research in the future."

The team used a variety of techniques to examine the outer and inner bailey of the site. These included the use of topographic survey methods and geophysical survey techniques -- comprising of magnetometry, earth resistance, ground penetrating radar (GPR) and electric resistivity tomography (ERT) survey.

Kristian Strutt concludes: "Our research so far has shown how the entire outer bailey of the monument was heavily built up in the Middle Ages, representing a substantial urban centre. Results have given us compelling evidence as to the nature of some of the structures. It is clear, however, that there is more non-intrusive work that could be carried out to further expand our understanding of the site."

The team hopes to return to complete the survey of the inner and outer baileys and survey the Romano-British settlement to the south of Old Sarum in Easter 2015. The project fieldwork in 2014 was used as a training season for undergraduate and postgraduate archaeology students at the University, continuing a long tradition of research-led teaching at some of the most impressive archaeological sites in the south of England. Previous fieldwork has been conducted by students at Portchester Castle, Netley Abbey and Bishop's Waltham Palace in Hampshire, and at Bodiam Castle in East Sussex.

Source: University of Southampton

Roman Gladiators ate a mostly vegetarian diet and drank a tonic of ashes after training

Anthropology unlocks clues about Roman gladiators' eating habits. Credit: OEAI, Pietsch

Roman gladiators ate a mostly vegetarian diet and drank ashes after training as a tonic. These are the findings of anthropological investigations carried out on bones of warriors found during excavations in the ancient city of Ephesos.

Historic sources report that gladiators had their own diet. This comprised beans and grains. Contemporary reports referred to them as "hordearii" ("barley eaters").

In a study by the Department of Forensic Medicine at the MedUni Vienna in cooperation with the Department of Anthropology at the Institute of Forensic Medicine at the University of Bern, bones were examined from a gladiator cemetery uncovered in 1993 which dates back to the 2nd or 3rd century BC in the then Roman city of Ephesos (now in modern-day Turkey). At the time, Ephesos was the capital of the Roman province of Asia and had over 200,000 inhabitants.

Using spectroscopy, stable isotope ratios (carbon, nitrogen and sulphur) were investigated in the collagen of the bones, along with the ratio of strontium to calcium in the bone mineral.

The result shows that gladiators mostly ate a vegetarian diet. There is virtually no difference in terms of nutrition from the local "normal population." Meals consisted primarily of grain and meat-free meals. The word "barley eater" relates in this case to the fact that gladiators were probably given grain of an inferior quality.

Build-up drink following physical exertion

The difference between gladiators and the normal population is highly significant in terms of the amount of strontium measured in their bones. This leads to the conclusion that the gladiators had a higher intake of minerals from a strontium-rich source of calcium. The ash drink quoted in literature probably really did exist. "Plant ashes were evidently consumed to fortify the body after physical exertion and to promote better bone healing," explains study leader Fabian Kanz from the Department of Forensic Medicine at the MedUni Vienna. "Things were similar then to what we do today -- we take magnesium and calcium (in the form of effervescent tablets, for example) following physical exertion." Calcium is essential for bone building and usually occurs primarily in milk products.

A further research project is looking at the migration of gladiators, who often came from different parts of the Roman Empire to Ephesos. The researchers are hoping that comparison of the bone data from gladiators with that of the local fauna will yield a number of differences.

Source: Medical University of Vienna

Were Neanderthals a sub-species of modern humans? New research says no

Depiction of Neanderthal (stock image). Credit: © procy_ab / Fotolia

In an extensive, multi-institution study led by SUNY Downstate Medical Center, researchers have identified new evidence supporting the growing belief that Neanderthals were a distinct species separate from modern humans (Homo sapiens), and not a subspecies of modern humans.

The study looked at the entire nasal complex of Neanderthals and involved researchers with diverse academic backgrounds. Supported by funding from the National Science Foundation and the National Institutes of Health, the research also indicates that the Neanderthal nasal complex was not adaptively inferior to that of modern humans, and that the Neanderthals' extinction was likely due to competition from modern humans and not an inability of the Neanderthal nose to process a colder and drier climate.

Samuel Márquez, PhD, associate professor and co-discipline director of gross anatomy in SUNY Downstate's Department of Cell Biology, and his team of specialists published their findings on the Neanderthal nasal complex in the November issue of The Anatomical Record, which is part of a special issue on The Vertebrate Nose: Evolution, Structure, and Function (now online).

They argue that studies of the Neanderthal nose, which have spanned over a century and a half, have been approaching this anatomical enigma from the wrong perspective. Previous work has compared Neanderthal nasal dimensions to modern human populations such as the Inuit and modern Europeans, whose nasal complexes are adapted to cold and temperate climates.

However, the current study joins a growing body of evidence that the upper respiratory tracts of this extinct group functioned via a different set of rules as a result of a separate evolutionary history and overall cranial bauplan (bodyplan), resulting in a mosaic of features not found among any population of Homo sapiens. Thus Dr. Márquez and his team of paleoanthropologists, comparative anatomists, and an otolaryngologist have contributed to the understanding of two of the most controversial topics in paleoanthropology -- were Neanderthals a different species from modern humans and which aspects of their cranial morphology evolved as adaptations to cold stress.

"The strategy was to have a comprehensive examination of the nasal region of diverse modern human population groups and then compare the data with the fossil evidence. We used traditional morphometrics, geometric morphometric methodology based on 3D coordinate data, and CT imaging," Dr. Márquez explained.

Anthony S. Pagano, PhD, anatomy instructor at NYU Langone Medical Center, a co-author, traveled to many European museums carrying a microscribe digitizer, the instrument used to collect 3D coordinate data from the fossils studied in this work, as spatial information may be missed using traditional morphometric methods. "We interpreted our findings using the different strengths of the team members," Dr. Márquez said, "so that we can have a 'feel' for where these Neanderthals may lie along the modern human spectrum."

Co-author William Lawson, MD, DDS, vice-chair and the Eugen Grabscheid research professor of otolaryngology and director of the Paleorhinology Laboratory of the Icahn School of Medicine at Mount Sinai, notes that the external nasal aperture of the Neanderthals approximates some modern human populations but that their midfacial prognathism (protrusion of the midface) is startlingly different. That difference is one of a number of Neanderthal nasal traits suggesting an evolutionary development distinct from that of modern humans. Dr. Lawson's conclusion is predicated upon nearly four decades of clinical practice, in which he has seen over 7,000 patients representing a rich diversity of human nasal anatomy.

Distinguished Professor Jeffrey T. Laitman, PhD, also of the Icahn School of Medicine and director of the Center for Anatomy and Functional Morphology, and Eric Delson, PhD, director of the New York Consortium in Evolutionary Primatology or NYCEP, are also co-authors and are seasoned paleoanthropologists, each approaching their fifth decade of studying Neanderthals. Dr. Delson has published on various aspects of human evolution since the early 1970's.

Dr. Laitman states that this article is a significant contribution to the question of Neanderthal cold adaptation in the nasal region, especially in its identification of a different mosaic of features than those of cold-adapted modern humans. Dr. Laitman's body of work has shown that there are clear differences in the vocal tract proportions of these fossil humans when compared to modern humans. This current contribution has now identified potentially species-level differences in nasal structure and function.

Dr. Laitman said, "The strength of this new research lies in its taking the totality of the Neanderthal nasal complex into account, rather than looking at a single feature. By looking at the complete morphological pattern, we can conclude that Neanderthals are our close relatives, but they are not us."

Ian Tattersall, PhD, emeritus curator of the Division of Anthropology at the American Museum of Natural History, an expert on Neanderthal anatomy and functional morphology who did not participate in this study, stated, "Márquez and colleagues have carried out a most provocative and intriguing investigation of a very significant complex in the Neanderthal skull that has all too frequently been overlooked." Dr. Tattersall hopes that "with luck, this research will stimulate future research demonstrating once and for all that Homo neanderthalensis deserves a distinctive identity of its own."

Source: SUNY Downstate Medical Center

Ancient human genome from southern Africa throws light on our origins

Professor Vanessa Hayes in the field.

The skeleton of a man who lived 2,330 years ago in the southernmost tip of Africa tells us about ourselves as humans, and throws some light on our earliest common genetic ancestry.

What can DNA from the skeleton of a man who lived 2,330 years ago in the southernmost tip of Africa tell us about ourselves as humans? A great deal when his DNA profile is one of the 'earliest diverged' -- oldest in genetic terms -- found to-date in a region where modern humans are believed to have originated roughly 200,000 years ago.

The man's maternal DNA, or 'mitochondrial DNA', was sequenced to provide clues to early modern human prehistory and evolution. Mitochondrial DNA provided the first evidence that we all come from Africa, and helps us map a figurative genetic tree, all branches deriving from a common 'Mitochondrial Eve'.
When archaeologist Professor Andrew Smith from the University of Cape Town discovered the skeleton at St. Helena Bay in 2010, very close to the site where 117,000 year old human footprints had been found -- dubbed "Eve's footprints" -- he contacted Professor Vanessa Hayes, an expert in African genomes.

At the time, Hayes was Professor of Genomic Medicine at the J. Craig Venter Institute in San Diego, California. She now heads the Laboratory for Human Comparative and Prostate Cancer Genomics at Sydney's Garvan Institute of Medical Research.

The complete 1.5 metre tall skeleton was examined by Professor Alan Morris, from the University of Cape Town. A biological anthropologist, Morris showed that the man was a 'marine forager'. A bony growth in his ear canal, known as 'surfer's ear', suggested that he spent some time diving for food in the cold coastal waters, while shells carbon-dated to the same period, and found near his grave, confirmed his seafood diet. Osteoarthritis and tooth wear placed him in his fifties.

Due to the acidity of the soil within the region, acquiring DNA from skeletons has proven problematic. The Hayes team therefore worked with the world's leading laboratory in ancient DNA research, namely that of paleogeneticist Professor Svante Pääbo at the Max Planck Institute for Evolutionary Anthropolgy in Leipzig, Germany, who successfully sequenced a Neanderthal.

The team generated a complete mitochondrial genome, using DNA extracted from a tooth and a rib. The findings provided genomic evidence that this man, from a lineage now presumed extinct, as well as other indigenous coastal dwellers like him, were the most closely related to 'Mitochondrial Eve'.

The study underlines the significance of southern African archaeological remains in defining human origins, and is published in the journal Genome Biology and Evolution, now online.

"We were thrilled that archaeologist Andrew Smith understood the importance of not touching the skeleton when he found it, and so did not contaminate its DNA with modern human DNA," said Professor Hayes.

"I approached Svante Pääbo because his lab is the best in the world at DNA extraction from ancient bones. This skeleton was very precious and we needed 
to make sure the sample was in safe hands."

"Alan Morris undertook some incredible detective work. He used his skills in forensics and murder cases to assemble a profile of the man behind the St Helena skeleton."

"Alan helped establish that this man was a marine hunter-gatherer -- in contrast to the contemporary inland hunter-gatherers from the Kalahari dessert. We were very curious to know how this man related to them."

"We also know that this man pre-dates migration into the region, which took place around 2,000 years ago when pastoralists made their way down the coast from Angola, bringing herds of sheep. We could demonstrate that our marine hunter-gatherer carried a different maternal lineage to these early migrants -- containing a DNA variant that we have never seen before."

"Because of this, the study gives a baseline against which historic herders at the Cape can now be compared."

While interested in African lineages, and how they interact with each other, Professor Hayes is especially keen for Africa to inform genomic research and medicine worldwide.

"One of the biggest issues at present is that no-one is assembling genomes from scratch -- in other words, when someone is sequenced, their genome is not pieced together as is," she said.

"Instead, sections of the sequenced genome are mapped to a reference genome. Largely biased by European contribution, the current reference is poorly representative of indigenous peoples globally."

"If we want a good reference, we have to go back to our early human origins."
"None of us that walk on this planet now are pure anything -- we are all mixtures. For example 1-4% of Eurasians even carry Neanderthal DNA"

"We need more genomes that don't have extensive admixture. In other words, we need to reduce the noise."

"In this study, I believe we may have found an individual from a lineage that broke off early in modern human evolution and remained geographically isolated. That would contribute significantly to refining the human reference genome."

Source: Garvan Institute of Medical Research

Ancient auditory illusions reflected in prehistoric art?

Here are prehistoric paintings of hoofed animals in a cave with thunderous reverberations located in Bhimbetka, India. Credit: S. Waller

During the 168th Meeting of the Acoustical Society of America (ASA), to be held October 27-31, 2014 at the Indianapolis Marriott Downtown Hotel, Steven J. Waller, of Rock Art Acoustics, will describe several ways virtual sound images and absorbers can appear supernatural.

"Ancient mythology explained echoes from the mouths of caves as replies from spirits, so our ancestors may have made cave paintings in response to these echoes and their belief that echo spirits inhabited rocky places such as caves or canyons," explained Waller.

Just as light reflection gives an illusion of seeing yourself duplicated in a mirror, sound waves reflecting off a surface are mathematically identical to sound waves emanating from a virtual sound source behind a reflecting plane such as a large cliff face. "This can result in an auditory illusion of somebody answering you from within the rock," Waller said.

Echoes of clapping can sound similar to hoof beats, as Waller pointed out, while multiple echoes within a cavern can blur together into a thunderous reverberation that mimics the sound of a herd of stampeding hoofed animals.

"Many ancient cultures attributed thunder in the sky to 'hoofed thunder gods,' so it makes sense that the reverberation within the caves was interpreted as thunder and inspired paintings of those same hoofed thunder gods on cave walls," said Waller. "This theory is supported by acoustic measurements, which show statistically significant correspondence between the rock art sites and locations with the strongest sound reflection."

Other acoustical characteristics may have also been misinterpreted by ancient cultures unaware of sound wave theory. Waller noticed a resemblance between an interference pattern and Stonehenge, so he set up an interference pattern in an open field with just two flutes "droning the same note" to explore what it would sound like.

"The quiet regions of destructive sound wave cancellation, in which the high pressure from one flute cancelled the low pressure from the other flute, gave blindfolded subjects the illusion of a giant ring of rocks or 'pillars' casting acoustic shadows," Waller said.

He traveled to England and demonstrated that Stonehenge does indeed radiate acoustic shadows that recreate the same pattern as interference. "My theory that musical interference patterns served as blueprints for megalithic stone circles -- many of which are called Pipers' Stones -- is supported by ancient legends of two magic pipers who enticed maidens to dance in a circle and turned them all into stones," Waller noted.

There are several important implications of Waller's research. Perhaps most significantly, it demonstrates that acoustical phenomena were culturally significant to early humans -- leading to the immediate conclusion that the natural soundscapes of archaeological sites should be preserved in their natural state for further study and greater appreciation.

"Even today, sensory input can be used to manipulate perception and lead to illusions inconsistent with scientific reality, which could have interesting practical applications for virtual reality and special effects in entertainment media," Waller said. "Objectivity is questionable, because a given set of data can be used to support multiple conclusions."

The history of humanity is full of such misinterpretations, such as the visual illusion that the sun moves around the earth. "Sound, which is invisible and has complex properties, can easily lead to auditory illusions of the supernatural," he added. "This, in turn, leads to the more general question: what other illusions are we living under due to other phenomena that we are currently misinterpreting?"

Presentation #2aAA11, "Virtual sound images and virtual sound absorbers misinterpreted as supernatural objects," by Stephen J. Waller will take place on Tuesday, October 28, 2014. The abstract can be found by searching for the presentation number here: https://asa2014fall.abstractcentral.com/planner.jsp

Source:  Acoustical Society of America (ASA)

In search of the origin of our brain

Nervous system in Nematostella vectensis embryos with different nerve cell populations, where the different neurons (here in green, blue and magenta) evidence asymmetry. Credit: Hiroshi Watanabe, Thomas Holstein / Nature Communication 5:5536, Macmillan Publishers Limited

While searching for the origin of our brain, biologists at Heidelberg University have gained new insights into the evolution of the central nervous system (CNS) and its highly developed biological structures. The researchers analysed neurogenesis at the molecular level in the model organism Nematostella vectensis. Using certain genes and signal factors, the team led by Prof. Dr. Thomas Holstein of the Centre for Organismal Studies demonstrated how the origin of nerve cell centralization can be traced back to the diffuse nerve net of simple and original lower animals like the sea anemone. The results of their research will be published in the journal "Nature Communications."

Like corals and jellyfish, the sea anemone -- Nematostella vectensis -- is a member of the Cnidaria family, which is over 700 million years old. It has a simple sack-like body, with no skeleton and just one body orifice. The nervous system of this original multicellular animal is organised in an elementary nerve net that is already capable of simple behaviour patterns. Researchers previously assumed that this net did not evidence centralization, that is, no local concentration of nerve cells. In the course of their research, however, the scientists discovered that the nerve net of the embryonic sea anemone is formed by a set of neuronal genes and signal factors that are also found in vertebrates.

According to Prof. Holstein, the origin of the first nerve cells depends on the Wnt signal pathway, named for its signal protein, Wnt. It plays a pivotal role in the orderly evolution of different types of animal cells. The Heidelberg researchers also uncovered an initial indication that another signal path is active in the neurogenesis of sea anemones -- the BMP pathway, which is instrumental for the centralization of nerve cells in vertebrates.

Named after the BMP signal protein, this pathway controls the evolution of various cell types depending on the protein concentration, similar to the Wnt pathway, but in a different direction. The BMP pathway runs at a right angle to the Wnt pathway, thereby creating an asymmetrical pattern of neuronal cell types in the widely diffuse neuronal net of the sea anemone. "This can be considered as the birth of centralization of the neuronal network on the path to the complex brains of vertebrates," underscores Prof. Holstein.

While the Wnt signal path triggers the formation of the primary body axis of all animals, from sponges to vertebrates, the BMP signal pathway is also involved in the formation of the secondary body axis (back and abdomen) in advanced vertebrates. "Our research results indicate that the origin of a central nervous system is closely linked to the evolution of the body axes," explains Prof. Holstein.

Source: Heidelberg, Universität