General

Archaeologists unearth royal entry complex at Herodian Hilltop Palace

Heritage Daily - Thu, 2014-12-18 18:39
The main feature is a 20-meter-high corridor with a complex system of arches, allowing the King and his entourage direct passage into the palace courtyard. During the excavations, the original palace vestibule, decorated with painted frescoes, was also exposed.

Part of the unique palace entry complex discovered at Herodian Hilltop Palace by Hebrew University archaeologists. (Credit: The Herodium Expedition at the Hebrew University of Jerusalem)

Archaeologists from The Hebrew University of Jerusalem’s Institute of Archaeology have discovered a monumental entryway to the Herodian Hilltop Palace at the Herodium National Park. The unique complex was uncovered during excavations by The Herodium Expedition in Memory of Ehud Netzer over the past year, as part of a project to develop the site for tourism.

The main feature of the entryway is an impressive corridor with a complex system of arches spanning its width on three separate levels. These arches buttressed the corridor’s massive side-walls, allowing the King and his entourage direct passage into the Palace Courtyard. Thanks to the supporting arches, the 20-meter long and 6-meter wide corridor has been preserved to a height of 20 meters.

The Hebrew University archaeologists — Roi Porat, Yakov Kalman and Rachel Chachy — suggest that the corridor was built as part of Herod’s plan to turn Herodium into a massive artificial volcano-shaped hill, a vast and impressive monument designed to commemorate the architect-King.

Surprisingly, during the course of the excavations, it became evident that the arched corridor was never actually in use, as prior to its completion it became redundant. This appears to have happened when Herod, aware of his impending death, decided to convert the whole hilltop complex into a massive memorial mound, a royal burial monument on an epic scale.

Whatever the case, the corridor was back-filled during the construction of the massive artificial hill at the end of Herod’s reign. The upper section of a new monumental stairway stretching from the hill’s base to its peak, constructed during the course of this building phase, appears to have been built over it.

The excavators point out that not only was the arched corridor covered over in the course of the construction of the hill-monument, but also all the structures earlier built by Herod on the hill’s slopes, including the Royal Theater uncovered by the expedition in 2008, while still led by Prof. Ehud Netzer, since deceased.

Part of the unique palace entry complex discovered at Herodian Hilltop Palace by Hebrew University archaeologists. (Credit: The Herodium Expedition at the Hebrew University of Jerusalem)

The only edifice not covered over was the splendid mausoleum-style structure, identified by Netzer and the expedition as Herod’s burial-place. Together with the monumental cone-shaped hill, this constituted the unique Herodian Royal burial-complex.

During the course of the current excavations, the original impressive Palace vestibule, blocked when the corridor became redundant, was also exposed. This entry-room, decorated with splendid painted frescoes, had a magnificent entryway leading into it, and offered evidence of the rebel occupation during the Great Revolt (66-71 CE), including Jewish Revolt coinage and crude temporary structures.

In addition, the excavations in the arched corridor also turned up impressive evidence from the Bar Kokhba Revolt period (132-135/6 CE): hidden tunnels dug on the site by the rebels as part of the guerilla warfare they waged against the Romans. Supported in part by wooden beams, these tunnels exited from the hilltop fortress by way of the corridor’s walls, through openings hidden in the corridor. One of the tunnels revealed a well-preserved construction of 20 or so cypress-wood branches, arranged in a cross-weave pattern to support the tunnel’s roof.

In the future, according to Mr. Shaul Goldstein, Director of Israel’s Nature and Parks Authority, the excavation of the arched corridor will allow visitors direct access to the Herodium hilltop palace-fortress, in the same way that Herod entered it two thousand years ago. There are also plans to provide tourists direct access from the structures on the slope, the Royal Theater and the Mausoleum, via the earlier monumental stairway, to the hilltop Palace.

Hebrew University of Jerusalem – Header Image – Aerial view of Herodium complex where Hebrew University archaeologists unearthed a unique palace entry complex. (Credit: Tatzpit Aerial Photography)

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Categories: General

550 Million Year Old Fossils Provide New Clues about Fossil Formation

Heritage Daily - Thu, 2014-12-18 18:30
A new study from University of Missouri and Virginia Tech researchers is challenging accepted ideas about how ancient soft-bodied organisms become part of the fossil record.

Findings suggest that bacteria involved in the decay of those organisms play an active role in how fossils are formed—often in a matter of just a few tens to hundreds of years. Understanding the relationship between decay and fossilization will inform future study and help researchers interpret fossils in a new way.

“The vast majority of the fossil record is composed of bones and shells,” said James Schiffbauer, assistant professor of geological sciences in the College of Arts and Science at MU. “Fossils of soft-bodied animals like worms and jellyfish, however, provide our only views onto the early evolution of animal life. Most hypotheses as to the preservation of these soft tissues focus on passive processes, where normal decay is halted or impeded in some way, such as by sealing off the sediments where the animal is buried. Our team is instead detailing a scenario where the actual decay helped ‘feed’ the process turning the organisms into fossils—in this case, the decay of the organisms played an active role in creating fossils.”

Schiffbauer studied a type of fossil animal from the Ediacaran Period called Conotubus, which lived more than 540 million years ago. He noted that these fossils are either replicated by, or associated with, pyrite—commonly called fool’s gold. The tiny fossils are tube-shaped and believed to have been composed of substances similar at least in hardness to human fingernails. These fossilized tubes are all that remain of the soft-bodied animals that inhabited them and most likely resembled worms or sea anemone-like animals.

“Most of the animals that had once lived on the Earth—with estimates eclipsing 10 billion species—were never preserved in the fossil record, but in our study we have a spectacular view of a tinier fraction of soft-bodied animals,” said Shuhai Xiao, professor of geobiology at Virginia Tech and a co-author on this study. “We asked the important questions of how, and under what special conditions, these soft-tissued organisms can escape the fate of complete degradation and be preserved in the rock record.”

Schiffbauer and his team performed a sophisticated suite of chemical analyses of these fossils to determine what caused the pyrite to form. They found that the fool’s gold on the organisms’ outer tube formed when bacteria first began consuming the animal’s soft tissues, with the decay actually promoting the formation of pyrite.

“Normally, the earth is good at cleaning up after itself,” Schiffbauer said. “In this case, the bacteria that helped break down these organisms also are responsible for preserving them as fossils. As the decay occurred, pyrite began replacing and filling in space within the animal’s exoskeleton, preserving them. Additionally, we found that this process happened in the space of a few years, perhaps even as low as 12 to 800. Ultimately, these new findings will help scientists to gain a better grasp of why these fossils are preserved, and what features represent the fossilization process versus original biology, so we can better reconstruct the evolutionary tree of life.”

Schiffbauer’s study, “A unifying model for Neoproterozoic-Palaeozoic exceptional fossil preservation through pyritization and carbonaceous compression,” was published in the journal Nature Communications. He collaborated with Shuhai Xiao and Jerry Hunter of Virginia Tech, Yaoping Cai and Hong Hua on Northwest University, Xi’an, China, Adam Wallace of the University of Delaware, Huifang Xu at the University of Wisconsin, Yongbo Peng of Indiana University and Alan Kaufman of the University of Maryland. Schiffbauer is the corresponding author.

University of Missouri-Columbia

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Categories: General

10 World Monuments – Now and then in pics

Heritage Daily - Thu, 2014-12-18 17:42
The Great Sphinx of Giza – 1871

Image Credit : WikiPedia

The Great Sphinx of Giza is a limestone statue of a reclining or couchant sphinx (a mythical creature with a lion’s body and a human head) that stands on the Giza Plateau on the west bank of the Nile in Giza, Egypt. The face of the Sphinx is generally believed to represent the face of the Pharaoh Khafra.

It is the largest monolith statue in the world, standing 73.5 metres (241 ft) long, 19.3 metres (63 ft) wide, and 20.22 m (66.34 ft) high. It is the oldest known monumental sculpture, and is commonly believed to have been built by ancient Egyptians of the Old Kingdom during the reign of the Pharaoh Khafra (c. 2558–2532 BC).

 

El Castillo, Chichen Itza – 1892

Image Credit : WikiPedia

El Castillo, also known as the Temple of Kukulcan, is a Mesoamerican step-pyramid that dominates the center of the Chichen Itza archaeological site in the Mexican state of Yucatán.

Built by the pre-Columbian Maya civilization sometime between the 9th and 12th centuries CE, El Castillo served as a temple to the god Kukulkan, the Yucatec Maya Feathered Serpent deity closely related to the god Quetzalcoatl known to the Aztecs and other central Mexican cultures of the Postclassic period.

 

The Washington Monument – 1862

Image Credit : WikiPedia

The Washington Monument is an obelisk on the National Mall in Washington, DC, built to commemorate George Washington, once commander-in-chief of the early Continental Army and the first American president.

The monument, made of marble, granite, and bluestone gneiss, standing 555 feet 5 1⁄8 inches (169.294 m) tall. Construction of the monument began in 1848, was halted from 1854 to 1877, and was finally completed in 1884.

 

Edfu – 1831

Image Credit : WikiPedia

The Temple of Edfu is an ancient Egyptian temple located on the west bank of the Nile in the city of Edfu which was known in Greco-Roman times as Apollonopolis Magna, after the chief god Horus-Apollo. It is one of the best preserved temples in Egypt. The temple, dedicated to the falcon god Horus, was built in the Ptolemaic period between 237 and 57 BC.

 

 Macchu Picchu – 1912

Image Credit : WikiPedia

Machu Picchu is a 15th-century Inca site located 2,430 metres (7,970 ft) above sea level. It is located in the Cusco Region, Urubamba Province, Machupicchu District in Peru. It is situated on a mountain ridge above the Sacred Valley which is 80 kilometres (50 mi) northwest of Cusco and through which the Urubamba River flows.

 

Colosseum – 1922

Image Credit : WikiPedia

The Colosseum or Coliseum, also known as the Flavian Amphitheatre is an elliptical amphitheatre in the centre of the city of Rome, Italy. Built of concrete and stone, it was the largest amphitheatre of the Roman Empire, and is considered one of the greatest works of Roman architecture and engineering. It is the largest amphitheatre in the world.

The Colosseum is situated just east of the Roman Forum. Construction began under the emperor Vespasian in 70 AD, and was completed in 80 AD under his successor and heir Titus.

 

Eiffel Tower – 1888

Image Credit : WikiPedia

The Eiffel Tower  is an iron lattice tower located on the Champ de Mars in Paris. It was named after the engineer Gustave Eiffel, whose company designed and built the tower. Erected in 1889 as the entrance arch to the 1889 World’s Fair, it was initially criticised by some of France’s leading artists and intellectuals for its design, but has become both a global cultural icon of France and one of the most recognisable structures in the world.

 

Abu Simbel – 1926

Image Credit : WikiPedia

The Abu Simbel temples are two massive rock temples in Abu Simbel, southern Egypt, near the border with Sudan. They are situated on the western bank of Lake Nasser, about 230 km southwest of Aswan (about 300 km by road). The twin temples were originally carved out of the mountainside during the reign of Pharaoh Ramesses II in the 13th century BC, as a lasting monument to himself and his queen Nefertari to commemorate his alleged victory at the Battle of Kadesh. However, the complex was relocated in its entirety in 1968, on an artificial hill made from a domed structure, high above the Aswan High Dam reservoir.

Mesa Verde – 1891

Image Credit : WikiPedia

Mesa Verde National Park is a U.S. National Park and UNESCO World Heritage Site located in Montezuma County, Colorado, United States. The Anasazi inhabited Mesa Verde between 600 to 1300, though there is evidence they left before the start of the 15th century. They were mainly subsistence farmers, growing crops on nearby mesas. By the year 750 the people were building mesa-top villages made of adobe. In the late 1190s they began to build the cliff dwellings for which Mesa Verde is famous.

 

Acropolis of Athens – 1872

Image Credit : WikiPedia

 

The Acropolis of Athens is an ancient citadel located on a high rocky outcrop above the city of Athens and contains the remains of several ancient buildings of great architectural and historic significance, the most famous being the Parthenon.

While there is evidence that the hill was inhabited as far back as the fourth millennium BC, it was Pericles (c. 495 – 429 BC) in the fifth century BC who coordinated the construction of the site’s most important buildings including the Parthenon, the Propylaia, the Erechtheion and the temple of Athena Nike.

 

Contributing Source : WikiPedia

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Categories: General

VIDEO: New lights give hope to stargazers

BBC test - Thu, 2014-12-18 14:45
New streetlights could reduce the orange glare of older sodium lights meaning clearer conditions for drivers and stargazers.
Categories: General

Season's Greetings

Wessex Archaeology - Thu, 2014-12-18 13:22

A winter’s scene, produced by our Graphics Team, showing one of the Neolithic houses from our Kingsmead, Horton excavations. This site has been nominated for Current Archaeology Rescue Dig of the Year 2015.   This Christmas, Wessex Archaeology has wished clients and colleagues seasonal greetings with our own festive e-card. Sending e-cards instead of traditional Christmas cards has enabled us to make donations to several charities. The charities supported by our different departments and regional offices this year are the RNLIMind, Salisbury Hospice, Bristol & Wales Cat Rescue, Shelter CymruScottish Fishermen's Trust, and Kent Search & Rescue

Thank you to everyone we have worked with this year – we hope you have a wonderful Christmas and look forward to seeing you in the New Year.  
Categories: General

Ancient relative of the elephant ‘holidayed in warm Arctic 125,000 years ago’

Heritage Daily - Thu, 2014-12-18 13:08
Previous age estimates of the fossils of American mastodons, a distant relative of elephants that inhabited North and Central America, suggest that they lived in the Arctic and Subarctic when the area was covered by ice caps.

Scientists have puzzled over this chronology as mastodons, which looked similar to modern-day Asian elephants, are known to have had a preference for forests and wetlands filled with heaps of leafy goods. In a paper published today in the Proceedings of the National Academy of Sciences, an international team suggests that the Arctic and Subarctic were just temporary “holiday homes” for mastodons when the local climate was warm around 125,000 years ago.

When the cold weather returned, their populations moved much further to the south, where the paper suggests they ultimately died out about 10,000 years ago. The findings debunk theories about over hunting by early humans being the reason for their disappearance from this region as these new dates show they were wiped out locally before human colonisation.

Researchers from the University of Oxford and the University of California radiocarbon dated collagen from 36 fossil teeth and bones of American mastodons from Alaska and Yukon. The dates for all of the fossils were older than previously thought. Alaska and Yukon were part of an ancient region known as eastern Beringia which is thought to have connected Asia with North America at various times. When taking mastodon habitat preferences and other ecological and geological information into account, the results show that mastodons probably only lived in eastern Beringia for a relatively short time when temperatures were as warm as they are today.

Dr Fiona Brock, a researcher from the Oxford Radiocarbon Accelerator Unit at the University of Oxford, said: ‘We applied dating techniques to target the collagen, avoiding contaminants such as varnish and glues, applied several years ago to strengthen the specimens, which otherwise may make the dates “younger” than they should be. Our state of the art techniques developed at Oxford to isolate and date individual amino acids from the bones have resulted in new dating evidence that provides a big shift in our thinking. The American mastodons weren’t suddenly wiped out by the humans but moved south where their population dwindled away.’

Lead author Grant Zazula, a palaeontologist from the Yukon Government, said: ‘The residency of mastodons in the north did not last long. The return to cold, dry glacial conditions along with the advance of continental glaciers around 75,000 years ago effectively wiped out their habitats. This new evidence suggests that mastodons disappeared from Beringia, and their populations became displaced to areas much further to the south, where they ultimately suffered complete extinction about 10,000 years ago.’

Over the course of the late Pleistocene (between about 10,000 and 125,000 years ago), the American mastodon (Mammut americanum) species was widespread. They lived in many parts of continental North America, as well as the tropics of Honduras and the Arctic coast of Alaska. Scholars had presumed that the mass extinction of mastodons was the result of rapid climate change in North America or that they were over hunted. However, the new findings show they died out several tens of millennia before the onset of climate changes at the end of the Ice Age 10,000 years ago. Researchers know that giant ground sloths, American camels, and giant beavers made the migration south as well, but they are still investigating what other groups of animals might have done this.

University of Oxford

 

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Categories: General

VIDEO: Grayling defends probation contracts

BBC test - Thu, 2014-12-18 12:11
New probation contracts worth £450m will be signed off by the government as 21 private companies take over the management of low and medium-risk offenders.
Categories: General

VIDEO: Has the high street got worse?

BBC test - Thu, 2014-12-18 09:17
Three years ago retails expert, Mary Portas, carried out a review of the high street for the government and the BBC takes her back to one of those towns, Stockport, to find out if anything has changed.
Categories: General

VIDEO: 'Ice pancakes' form on River Dee

BBC test - Thu, 2014-12-18 07:46
Ice pancake formations, more commonly seen in the Antarctic, have been photographed on the River Dee in Aberdeenshire.
Categories: General

From World War I fairly lights to Crimbo: The real meaning of Christmas customs

24 Hour Museum - Thu, 2014-12-18 00:00
Who knew that baubles used to be viewed with disdain and the Oxford English Dictionary editors originally consider nativity "a bit posh"? Find out the truth behind Christmas words.
Categories: General

VIDEO: Car smoke ban proposed for 2015

BBC test - Wed, 2014-12-17 22:37
Smoking in a car while travelling with children could be a criminal offence in England and Wales from October 2015.
Categories: General

What did the Romans ever do for us? They left a water warning

Heritage Daily - Wed, 2014-12-17 19:27
As all good Monty Python fans know, water technologies feature large in the legacy of benefits left by Roman civilisation.

But while aqueducts, sewers and baths retain an obvious presence in the landscape and in the archaeological record, the Romans’ largest and most important water achievement may have been “virtual”.

The Romans developed networks of trade and food supply that enabled them to escape local water constraints, in a way that is explained in a new study in the journal Hydrology and Earth System Sciences. Fertile regions such as southern Spain or Italy’s Po valley would grow lots of food and ship it back to Rome or to the drier outposts of the Empire.

Embedded within this is a what geographers call a virtual water trade – an indirect way of shifting this precious resource from wetter, less populated areas to those regions with more people or a less consistent climate.

The map below shows this in action. The amount of virtual water imports (a) and exports (b) in different parts of the Empire are illustrated by the size of the circles. The numbers express this in tonnes of grain. Rome is by far the largest water importer, followed by Alexandria and Memphis in Egypt, and Ephesus and Antioch in modern-day Turkey. Spain and Egypt were the biggest exporters.

All ships lead to Rome

Virtual water imports across the Roman Empire. Dermody et al

The paper’s primary author, Brian Dermody at the University of Utrecht, suggests this sophisticated water economy ultimately contributed to its own downfall as it enabled urban populations to boom beyond sustainable levels.

Does this sound uncomfortably familiar? In the next 30 years we are facing a critical combination of inter-related stresses on the core resources that keep our civilisation running. As it happens, the Romans gave us a word for that too – the “food-water-energy nexus” (from the Latin nectere, to bind together).

So are we doomed to the same fate as the Romans?

Increased energy use

As its name suggests, the nexus recognises that different resources are intimately interconnected. We need water for drinking, washing and for industry; but we also need it to grow food, and around 70% of global fresh water supply is used for farming. As populations grow and become more wealthy, demand for food will increase, placing pressure on domestic water supply and industrial output.

Economic growth and technological developments increase energy use, driving additional demand for water in power station cooling and other uses in energy generation. The rise in shale gas extraction provides a stark illustration of this: irrespective of the many other ethical and political issues surrounding fracking, it is its thirst for water (used to force the hydrocarbons out of the rocks) that may prove the key limitation. After all, 38% of the world’s shale gas resources are located in areas of extremely high water stress or arid conditions. In the UK, plans for fracking in major regions such as the Severn catchment could place untenable pressure on water use for farming and domestic supply.

In all this complexity, the mega-issue of climate change arguably plays only an aggravating role. Intensive farming is degrading soil, its primary resource base, up to 100 times faster than the rates at which it is formed. Non-renewable fuel and mineral resources are becoming increasingly scarce and more costly to recover. And renewable, drinkable water supplies are under often extreme threat.

Solving climate change will not in itself solve the problems of the food-water-energy nexus; in fact it should be apparent that our effective response to climate change is deeply entwined with a sustainable untangling of the nexus.

Interconnected threats

Like the Romans, the “modern” response to the emergent limitations of the food-water-energy nexus was economic. Global trade through the 20th century allowed us to circumvent local or regional resource limitations, stimulating unprecedented population growth along with rising wealth and living standards.

Many countries could not hope to maintain their current consumption of food and resources if they were forced become self-reliant on resources available within their territory – in the current economic and technological conditions, at least.

This makes the global economy vulnerable to regional problems. Look at this year’s escalation of tension between Russia and the West, for instance. Sanctions imposed by both sides have affected international trade in wheat and other crops, leading to supply shortages or gluts in some places and the destabilisation of farming economies and farmer incomes in others – and has raised the threat of disruption to transnational energy supplies. Again, the challenges of the nexus – and our vulnerability to those changes – transcend the background threat of climate change.

So, faced with challenges which appear strikingly similar, what can our postmodern, self-aware civilisation do to avoid the fate of the Romans? We cannot stop the nexus any more than we can prevent the climate change that will result from our current levels of greenhouse gas emission. Business as usual is clearly not an option. In the absence of a magic bullet (or something much worse, an environmental disaster or collapse), resilience is the key.

One advantage we have over the Romans is information; we can learn from precedent. We can see what is over the horizon and make a judgement on how it may impact our lives and livelihoods. The challenge, unfortunately, remains how to stimulate people and politicians to change in response to those dangers. However human nature means we are as ready to listen to soothsayers as scientists and, in that respect, we and the Romans are still very much the same.

Written by Jonathan Bridge

Lecturer in Environmental Engineering at University of Liverpool

The Conversation – Header Image : WikiPedia

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Categories: General

An Impressive 2,800 Year Old Farm House discovered in Rosh Ha-‘Ayin

Heritage Daily - Wed, 2014-12-17 19:15
An impressive farm house, 2,800 years old, which comprised twenty-three rooms, was exposed in recent weeks during archaeological excavations the Israel Antiquities Authority is carrying out in Rosh Ha-‘Ayin before the city is enlarged in an initiative by the Ministry of Construction.

According to Amit Shadman, excavation director on behalf of the Israel Antiquities Authority, “The farm, which is extraordinarily well-preserved, extends across an area of 30 × 40 m and was built in the eighth century BCE, the time of the Assyrian conquest.

Farm houses during this period served as small settlements of sorts whose inhabitants participated in processing agricultural produce. The numerous wine presses discovered in the vicinity of the settlement indicate the wine industry was the most important branch of agriculture in the region. A large silo, which was used to store grain, shows that the ancient residents were also engaged in growing cereal.”

The face of Heracles. Photographic credit: Robert Kool, courtesy of the Israel Antiquities Authority

According to Shadman the building continued to be used during the Persian period (also known as the Time of the Return to Zion) in the sixth century BCE, and in the Hellenistic period as well which began in the country with the arrival of Alexander the Great, one of the greatest military leaders of antiquity. With Alexander’s victory over the Persian army in 333 BCE he embarked upon numerous successful military campaigns. His campaign in Israel did not encounter any special difficulties and the country opened its gates to the great warrior.

Evidence of a Greek presence in the region was uncovered on one of the floors of the building in the form of a rare silver coin bearing the military leader’s name – ΑΛΕΞΑNΔΡΟΥ. One can also discern the image of the god Zeus on that side of the coin, while the head of Heracles appears on its reverse.

During the Ottoman period a lime kiln was dug into the structure which utilized the stones in the building as ready source of raw material.

In light of this impressive building’s excellent state of preservation, the Israel Antiquities Authority and Ministry of Construction decided to conserve the structure in situ for the benefit of the city’s residents and the visiting public.

Israel Antiquities Authority – Header Image – An aerial photograph of the farm house. Photographic credit: Skyview Company, courtesy of the Israel Antiquities Authority

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Categories: General

MAI dig suggests human presence at Old Vero Man site

Heritage Daily - Wed, 2014-12-17 18:47
Were he alive today, E.H. Sellards, Florida state geologist in the early 1900s, would likely have reveled in the validation of his controversial theory that humans co-existed with large prehistoric animals some 14,000 years ago in Vero Beach, Florida.

In what MAI Director James Adovasio, Ph.D., describes as the most extensive Paleoindian excavation currently under way in all of North America, that being the Old Vero Man site where Sellards drew his now century-old conclusions, evidence uncovered recently by MAI positively demonstrates the contemporaneous presence of humans and late Pleistocene animals.

The MAI began its Vero excavation last year at the invitation of the Old Vero Ice Age Sites Committee (OVIASC), a dedicated group of citizens determined to define Vero’s rightful place in the archaeological record. OVIASC has been instrumental in raising the funds necessary for the first season of excavation that ran January to May 2014, and will commence again in January 2015.

Although actual human remains were not retrieved in the dig’s first round, certain artifacts identified during the excavation, among them burned fragments of bone, some with cut marks; could only be the work of human beings, Adovasio said.

“It’s taken more than 100 years, but we now know that Sellards was right,” he added, crediting rigorous excavation protocols and new technology that enabled investigators to proceed with a precise understanding of the site’s geology – an advantage Sellards did not have.

Further, radiocarbon dating of the soil where much of the cultural materials have been found – in all, 170 species of plants and animals from MAI and earlier investigations – goes back 13,000-14,000 calendar years, making Vero the oldest terrestrial archaeological site in all of Florida and one of the oldest in the entire Southeast U.S.

Adovasio said MAI archaeologists and students also uncovered a buried soil layer dating back some 19,000 years, and that is where they intend to concentrate their second excavation in January.

“If that stratum or layer produces cultural materials, it will be one of the oldest locations in all of North or South America,” Adovasio added.

While the current findings are significant to Floridians, Adovasio said the Vero site also plays a role in the more far-reaching debate surrounding the founding populations of the Americas. Historically, the first agreed-upon culture in the Americas was called Clovis, after a site discovered in New Mexico in the 1920s. Sites identified as Clovis dated around 11,200 – 11,500 radiocarbon years ago. But, beginning in the 1970s, sites predating Clovis began to be discovered, such as Pennsylvania’s Meadowcroft Rockshelter, where Adovasio was principal excavator; Monte Verde in Chile and Gault in Central Texas.

Those discoveries – and now Vero – go a long way toward proving Clovis believers wrong and turning most archaeologists on Adovasio’s side of the debate.

Moving forward, Adovasio said that subsequent investigations are expected to reveal the interrelationship of human, animal and plant populations at Vero. He said their hope is “to distinguish lifestyles of the folks who might have lived at Vero in terms of how much they match or don’t match other behavioral models from other sites.”

Adovasio and his colleagues (C. Andrew Hemmings, A.E. Marjenin, F.J. Vento and A. Vega) made their first presentation on the Vero excavation last month at the 71st Annual Southeastern Archaeological Conference in Greenville, South Carolina. Their symposium presentation was titled “The Old Vero Man Site: Current Investigations Suggest Pleistocene Human Occupation.”

The faunal and floral materials recovered, among them a bone tentatively identified as that of a dire wolf, now extinct, are being studied in the archaeology labs at Mercyhurst University, creating a rare and historic opportunity for students.

MAI is now working with Florida Atlantic University scientists, who intend to analyze ancient DNA found at the dig site to provide yet another glimpse of the Florida landscape at the end of the last Ice Age.

Mercyhurst University

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Categories: General

VIDEO: Pakistan attack 'darkest day of my life'

BBC test - Wed, 2014-12-17 18:30
BBC News speaks to Shah Jehan, a UK relative of two young boys who died in the Peshawar school attack.
Categories: General

Tooth loss in birds occurred about 116 million years ago

Heritage Daily - Wed, 2014-12-17 18:19
Research team led by UC Riverside and Montclair State University biologists confirms that inactivation of tooth genes occurred convergently in birds, turtles, and multiple mammalian lineages

The absence of teeth or “edentulism” has evolved on multiple occasions within vertebrates including birds, turtles, and a few groups of mammals such as anteaters, baleen whales and pangolins. Where early birds are concerned, the fossil record is fragmentary. A question that has intrigued biologists is: Based on this fossil record, were teeth lost in the common ancestor of all living birds or convergently in two or more independent lineages of birds?

A research team led by biologists at the University of California, Riverside and Montclair State University, NJ, has found an answer. Using the degraded remnants of tooth genes in birds to determine when birds lost their teeth, the team reports in the Dec. 12 issue of Science that teeth were lost in the common ancestor of all living birds more than 100 million years ago.

“One of the larger lessons of our finding is that ‘dead genes,’ like the remnants of dead organisms that are preserved in the fossil record, have a story to tell,” said Mark Springer, a professor of biology and one of the lead authors of the study along with Robert Meredith at Montclair State University who was previously a graduate student and postdoctoral researcher in Springer’s laboratory. “DNA from the crypt is a powerful tool for unlocking secrets of evolutionary history.”

Springer explained that edentulism and the presence of a horny beak are hallmark features of modern birds.

“Ever since the discovery of the fossil bird Archaeopteryx in 1861, it has been clear that living birds are descended from toothed ancestors,” he said. “However, the history of tooth loss in the ancestry of modern birds has remained elusive for more than 150 years.”

All toothless/enamelless vertebrates are descended from an ancestor with enamel-capped teeth. In the case of birds, it is theropod dinosaurs. Modern birds use a horny beak instead of teeth, and part of their digestive tract to grind up and process food.

Tooth formation in vertebrates is a complicated process that involves many different genes. Of these genes, six are essential for the proper formation of dentin (DSPP) and enamel (AMTN, AMBN, ENAM, AMELX, MMP20).

The researchers examined these six genes in the genomes of 48 bird species, which represent nearly all living bird orders, for the presence of inactivating mutations that are shared by all 48 birds. The presence of such shared mutations in dentin and enamel-related genes would suggest a single loss of mineralized teeth in the common ancestor of all living birds.

Springer, Meredith, and other members of their team found that the 48 bird species share inactivating mutations in both dentin-related (DSPP) and enamel-related genes (ENAM, AMELX, AMTN, MMP20), indicating that the genetic machinery necessary for tooth formation was lost in the common ancestor of all modern birds.

“The presence of several inactivating mutations that are shared by all 48 bird species suggests that the outer enamel covering of teeth was lost around ~116 million years ago,” Springer said.

On the basis of fossil and molecular evidence, the researchers propose a two-step scenario whereby tooth loss and beak development evolved together in the common ancestor of all modern birds. In the first stage, tooth loss and partial beak development began on the anterior portion of both the upper and lower jaws. The second stage involved concurrent progression of tooth loss and beak development from the anterior portion of both jaws to the back of the rostrum.

“We propose that this progression ultimately resulted in a complete horny beak that effectively replaced the teeth and may have contributed to the diversification of living birds,” Springer said.

The research team also examined the genomes of additional toothless/enamelless vertebrates including three turtles and four mammals (pangolin, aardvark, sloth, and armadillo) for inactivating mutations in the dentin- and enamel-related genes. For comparison, the researchers looked at the genomes of mammalian taxa with enamel-capped teeth.

“All edentulous vertebrate genomes that we examined are characterized by inactivating mutations in DSPP, AMBN, AMELX, AMTN, ENAM, and MMP20, rendering these genes non-functional,” Springer said. “The dentin-related gene DSPP is functional in vertebrates with enamelless teeth – sloth, aardvark, armadillo. All six genes are functional in the American alligator, a representative of Crocodylia, the closest living relatives of birds, and mammalian taxa with enamel capped teeth.”

The research was supported, in part, by a grant to Springer from the National Science Foundation.

Springer and Meredith were joined in the research by Guojie Zhang at China National GeneBank, China; M. Thomas P. Gilbert at the University of Copenhagen Oster Voldgade, Denmark; and Erich D. Jarvis at Duke University Medical Center, NC.

All the scientists are coauthors with several others, including UC Riverside biologist John Gatesy, on a second paper in the same issue of Science. This paper employs the same 48 bird genomes to ask the question: “What makes a bird a bird?”

“The new bird genomes represent a major advance given that only a handful of bird genomes – zebra finch, turkey, chicken and duck – were previously available,” Springer said.

University of California – Riverside

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Study Hints that Ancient Earth Made Its Own Water—Geologically

Heritage Daily - Wed, 2014-12-17 18:13
A new study is helping to answer a longstanding question that has recently moved to the forefront of earth science: Did our planet make its own water through geologic processes, or did water come to us via icy comets from the far reaches of the solar system?

The answer is likely “both,” according to researchers at The Ohio State University— and the same amount of water that currently fills the Pacific Ocean could be buried deep inside the planet right now.

At the American Geophysical Union (AGU) meeting on Wednesday, Dec. 17, they report the discovery of a previously unknown geochemical pathway by which the Earth can sequester water in its interior for billions of years and still release small amounts to the surface via plate tectonics, feeding our oceans from within.

In trying to understand the formation of the early Earth, some researchers have suggested that the planet was dry and inhospitable to life until icy comets pelted the earth and deposited water on the surface.

Wendy Panero, associate professor of earth sciences at Ohio State, and doctoral student Jeff Pigott are pursuing a different hypothesis: that Earth was formed with entire oceans of water in its interior, and has been continuously supplying water to the surface via plate tectonics ever since.

Researchers have long accepted that the mantle contains some water, but how much water is a mystery. And, if some geological mechanism has been supplying water to the surface all this time, wouldn’t the mantle have run out of water by now?

Because there’s no way to directly study deep mantle rocks, Panero and Pigott are probing the question with high-pressure physics experiments and computer calculations.

“When we look into the origins of water on Earth, what we’re really asking is, why are we so different than all the other planets?” Panero said. “In this solar system, Earth is unique because we have liquid water on the surface. We’re also the only planet with active plate tectonics. Maybe this water in the mantle is key to plate tectonics, and that’s part of what makes Earth habitable.”

This plate tectonics diagram from the Byrd Polar and Climate Research Center shows how mantle circulation delivers new rock to the crust via mid-ocean ridges. New research suggests that mantle circulation also delivers water to the oceans.

Central to the study is the idea that rocks that appear dry to the human eye can actually contain water—in the form of hydrogen atoms trapped inside natural voids and crystal defects. Oxygen is plentiful in minerals, so when a mineral contains some hydrogen, certain chemical reactions can free the hydrogen to bond with the oxygen and make water.

Stray atoms of hydrogen could make up only a tiny fraction of mantle rock, the researchers explained. Given that the mantle is more than 80 percent of the planet’s total volume, however, those stray atoms add up to a lot of potential water.

In a lab at Ohio State, the researchers compress different minerals that are common to the mantle and subject them to high pressures and temperatures using a diamond anvil cell—a device that squeezes a tiny sample of material between two diamonds and heats it with a laser—to simulate conditions in the deep Earth. They examine how the minerals’ crystal structures change as they are compressed, and use that information to gauge the minerals’ relative capacities for storing hydrogen. Then, they extend their experimental results using computer calculations to uncover the geochemical processes that would enable these minerals to rise through the mantle to the surface—a necessary condition for water to escape into the oceans.

In a paper now submitted to a peer-reviewed academic journal, they reported their recent tests of the mineral bridgmanite, a high-pressure form of olivine. While bridgmanite is the most abundant mineral in the lower mantle, they found that it contains too little hydrogen to play an important role in Earth’s water supply.

Another research group recently found that ringwoodite, another form of olivine, does contain enough hydrogen to make it a good candidate for deep-earth water storage. So Panero and Pigott focused their study on the depth where ringwoodite is found—a place 325-500 miles below the surface that researchers call the “transition zone”—as the most likely region that can hold a planet’s worth of water. From there, the same convection of mantle rock that produces plate tectonics could carry the water to the surface.

One problem: If all the water in ringwoodite is continually drained to the surface via plate tectonics, how could the planet hold any in reserve?

For the research presented at AGU, Panero and Pigott performed new computer calculations of the geochemistry in the lowest portion of the mantle, some 500 miles deep and more. There, another mineral, garnet, emerged as a likely water-carrier—a go-between that could deliver some of the water from ringwoodite down into the otherwise dry lower mantle.

If this scenario is accurate, the Earth may today hold half as much water in its depths as is currently flowing in oceans on the surface, Panero said—an amount that would approximately equal the volume of the Pacific Ocean. This water is continuously cycled through the transition zone as a result of plate tectonics.

“One way to look at this research is that we’re putting constraints on the amount of water that could be down there,” Pigott added.

Panero called the complex relationship between plate tectonics and surface water “one of the great mysteries in the geosciences.” But this new study supports researchers’ growing suspicion that mantle convection somehow regulates the amount of water in the oceans. It also vastly expands the timeline for Earth’s water cycle.

“If all of the Earth’s water is on the surface, that gives us one interpretation of the water cycle, where we can think of water cycling from oceans into the atmosphere and into the groundwater over millions of years,” she said. “But if mantle circulation is also part of the water cycle, the total cycle time for our planet’s water has to be billions of years.”

Ohio State University

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Past global warming similar to today’s

Heritage Daily - Wed, 2014-12-17 18:08
The rate at which carbon emissions warmed Earth’s climate almost 56 million years ago resembles modern, human-caused global warming much more than previously believed, but involved two pulses of carbon to the atmosphere, University of Utah researchers and their colleagues found.

The findings mean the so-called Paleocene-Eocene thermal maximum, or PETM, can provide clues to the future of modern climate change. The good news: Earth and most species survived. The bad news: It took millennia to recover from the episode, when temperatures rose by 5 to 8 degrees Celsius (9 to 15 degrees Fahrenheit).

“There is a positive note in that the world persisted, it did not go down in flames, it has a way of self-correcting and righting itself,” says University of Utah geochemist Gabe Bowen, lead author of the study published today in the journal Nature Geoscience. “However, in this event it took almost 200,000 years before things got back to normal.”

Bowen and colleagues report that carbonate or limestone nodules in Wyoming sediment cores show the global warming episode 55.5 million to 55.3 million years ago involved the average annual release of a minimum of 0.9 petagrams (1.98 trillion pounds) of carbon to the atmosphere, and probably much more over shorter periods.

That is “within an order of magnitude of, and may have approached, the 9.5 petagrams [20.9 trillion pounds] per year associated with modern anthropogenic carbon emissions,” the researchers wrote. Since 1900, human burning of fossil fuels emitted an average of 3 petagrams per year – even closer to the rate 55.5 million years ago.

Each pulse of carbon emissions lasted no more than 1,500 years. Previous conflicting evidence indicated the carbon release lasted anywhere from less than a year to tens of thousands of years. The new research shows atmospheric carbon levels returned to normal within a few thousand years after the first pulse, probably as carbon dissolved in the ocean. It took up to 200,000 years for conditions to normalize after the second pulse.

The new study also ruled as unlikely some theorized causes of the warming episode, including an asteroid impact, slow melting of permafrost, burning of organic-rich soil or drying out of a major seaway. Instead, the findings suggest, in terms of timing, that more likely causes included melting of seafloor methane ices known as clathrates, or volcanism heating organic-rich rocks and releasing methane.

“The Paleocene-Eocene thermal maximum has stood out as a striking, but contested, example of how 21st-century-style atmospheric carbon dioxide buildup can affect climate, environments and ecosystems worldwide,” says Bowen, an associate professor of geology and geophysics at the University of Utah.

“This new study tightens the link,” he adds. “Carbon release back then looked a lot like human fossil-fuel emissions today, so we might learn a lot about the future from changes in climate, plants, and animal communities 55.5 million years ago.”

Bowen cautioned, however, that global climate already was much warmer than today’s when the Paleocene-Eocene warming began, and there were no icecaps, “so this played out on a different playing field than what we have today.”

Sudy co-author Scott Wing, a paleobiologist at the Smithsonian Institution in Washington, adds: “This study gives us the best idea yet of how quickly this vast amount of carbon was released at the beginning of the global warming event we call the Paleocene-Eocene thermal maximum. The answer is just a few thousands of years or less. That’s important because it means the ancient event happened at a rate more like human-caused global warming than we ever realized.”

Bowen and Wing conducted the study with University of Utah geology and geophysics master’s graduate Bianca Maibauer and technician Amy Steimke; Mary Kraus of University of Colorado, Boulder; Ursula Rohl and Thomas Westerhold of the University of Bremen, Germany; Philip Gingerich of the University of Michigan; and William Clyde of the University of New Hampshire. The study was funded by the National Science Foundation and the German Research Foundation.

A rainbow appears over National Science Foundation-funded drilling site in Wyoming’s Bighorn Basin. In a study led by University of Utah geochemist Gabe Bowen, sediment cores drilled at the site revealed a global warming episode almost 56 million years ago resembled today’s in terms of the size and duration of carbon releases to the atmosphere.
Credit: Elisabeth Denis, Pennsylvania State University.

Effects of the Paleocene-Eocene Warming

Bowen says previous research has shown that during the Paleocene-Eocene warm period, there was “enhanced storminess in some areas, increased aridity in other places. We see continent-scale migration of animals and plants, ranges are shifting. We see only a little bit of extinction – some groups of deep-sea foraminifera, one-cell organisms that go extinct at the start of this event. Not much else went extinct.”

“We see the first wave of modern mammals showing up,” including ancestral primates and hoofed animals,” he adds. Oceans became more acidic, as they are now.

“We look through time recorded in those rocks, and this warming event stands out, and everything happens together,” Bowen says. “We can look back in Earth’s history and say this is how this world works, and it’s totally consistent with the expectation that carbon dioxide change today will be associated with these other sorts of change.”

The Paleocene-Eocene thermal maximum also points to the possibility of runaway climate change enhanced by feedbacks. “The fact we have two releases may suggest that second one was driven by the first,” perhaps, for example, if the first warming raised sea temperatures enough to melt massive amounts of frozen methane, Bowen says.

Drilling into Earth’s Past

The new study is part of a major drilling project to understand the 56-milion-year-old warming episode, which Bowen says first was discovered in 1991. The researchers drilled long, core-shaped sediment samples from two boreholes at Polecat Bench in northern Wyoming’s Bighorn Basin, east of Cody and just north of Powell.

“This site has been excavated for well over 100 years by paleontologists studying fossil mammals,” Bowen says. “It documents that transition from the early mammals we see after the extinction of the dinosaurs to Eocene mammals, which are in groups that are familiar today. There is a great stratigraphic sequence of more than 2 kilometers (1.2 miles) of rocks, from 65 million years ago to 52 million years ago.”

The Paleocene-Eocene warming is recorded in the banded, flood-deposit tan and rusted red rock and soil layers of the Willwood formation, specifically within round, gray to brown-gray carbonate nodules in those rocks. They are 2 inches to 0.1 inches diameter.

By measuring carbon isotope ratios in the nodules, the researchers found that during each 1,500-year carbon release, the ratio of carbon-13 to carbon-12 in the atmosphere declined, indicating two large releases of carbon dioxide or methane, both greenhouse gases from plant material. The decline was three parts per thousand for the first pulse, and 5.7 parts per thousand for the second.

Previous evidence from seafloor sediments elsewhere is consistent with two Paleocene-Eocene carbon pulses, which “means we don’t think this is something is unique to northern Wyoming,” Bowen says. “We think it reflects a global signal.”

What Caused the Prehistoric Warming?

The double-barreled carbon release at the Paleocene-Eocene time boundary pretty much rules out an asteroid or comet impact because such a catastrophe would have been “too quick” to explain the 1,500-year duration of each carbon pulse, Bowen says.

Another theory: oxidation of organic matter – as permafrost thawed, as peaty soils burned or as a seaway dried up – may have caused the Paleocene-Eocene warming. But that would have taken tens of thousands of years, far slower than what the study found, he adds. Volcanoes releasing carbon gases also would have been too slow.

Bowen says the two relatively rapid carbon releases (about 1,500 years each) are more consistent with warming oceans or an undersea landslide triggering the melting of frozen methane on the seafloor and large emissions to the atmosphere, where it became carbon dioxide within decades. Another possibility is a massive intrusion of molten rock that heated overlying organic-rich rocks and released a lot of methane, he says.

University of Utah

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Asteroid that wiped out dinosaurs may have nearly knocked off mammals, too

Heritage Daily - Wed, 2014-12-17 18:00
The extinction of the dinosaurs 66 million years ago is thought to have paved the way for mammals to dominate, but a new study shows that many mammals died off alongside the dinosaurs.

Metatherian mammals–the extinct relatives of living marsupials (“mammals with pouches”, such as opossums) thrived in the shadow of the dinosaurs during the Cretaceous period. The new study, by an international team of experts on mammal evolution and mass extinctions, shows that these once-abundant mammals nearly followed the dinosaurs into oblivion.

When a 10-km-wide asteroid struck what is now Mexico at the end of the Cretaceous and unleashed a global cataclysm of environmental destruction, some two-thirds of all metatherians living in North America perished. This includes more than 90% of species living in the northern Great Plains of the USA, the best area in the world for preserving latest Cretaceous mammal fossils.

This diagram is showing how severely metatherian mammals were affected when an asteroid hit Earth at the end of the Cretaceous, 66 million years ago. In North America, the number of metatherian species dropped from twenty species within the last million years of the Cretaceous Period, to just three species in the first million years of the Paleogene Period. Credit: Dr Thomas Williamson

In the aftermath of the mass extinction, metatherians would never recover their previous diversity, which is why marsupial mammals are rare today and largely restricted to unusual environments in Australia and South America.

Taking advantage of the metatherian demise were the placental mammals: species that give live birth to well-developed young. They are ubiquitous across the globe today and include everything from mice to men.

Dr. Thomas Williamson of the New Mexico Museum of Natural History and Science, lead author on the study, said: “This is a new twist on a classic story. It wasn’t only that dinosaurs died out, providing an opportunity for mammals to reign, but that many types of mammals, such as most metatherians, died out too – this allowed advanced placental mammals to rise to dominance.”

Dr. Steve Brusatte of the University of Edinburgh’s School of GeoSciences, an author on the report, said: “The classic tale is that dinosaurs died out and mammals, which had been waiting in the wings for over 100 million years, then finally had their chance. But our study shows that many mammals came perilously close to extinction. If a few lucky species didn’t make it through, then mammals may have gone the way of the dinosaurs and we wouldn’t be here.”

Dr. Gregory Wilson of the University of Washington also took part in the study.

The new study is published in the open access journal ZooKeys. It reviews the Cretaceous evolutionary history of metatherians and provides the most up-to-date family tree for these mammals based on the latest fossil records, which allowed researchers to study extinction patterns in unprecedented detail.

Pensoft Publishers

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North Atlantic signalled Ice Age thaw 1,000 years before it happened, reveals new research

Heritage Daily - Wed, 2014-12-17 16:22
The Atlantic Ocean at mid-depths may have given out early warning signals – 1,000 years in advance – that the last Ice Age was going to end, scientists report today in the journal Paleoceanography.

Scientists had previously known that at the end of the last Ice Age, around 14,700 years ago, major changes occurred to the Atlantic Ocean in a period known as the Bolling-Allerod interval. During this period, as glaciers melted and the Earth warmed, the currents of the Atlantic Ocean at its deepest levels changed direction.

The researchers have analysed the chemistry of 24 ancient coral fossils from the North Atlantic Ocean to learn more about the circulation of its waters during the last Ice Age. They found that the corals recorded a high variability in the currents of the Atlantic Ocean at mid-depths, around 2km below the surface, up to 1,000 years prior to the Bolling-Allerod interval. The team suggests that these changes may have been an early warning signal that the world was poised to switch from its glacial state to the warmer world we know today, and that the changes happened first at mid-depths.

The study was carried out by researchers from Imperial College London in conjunction with academics from the Scottish Marine Institute, the University of Bristol and Caltech Division of Geology and Planetary Sciences.

Dr David Wilson, from the Department of Earth Science and Engineering at Imperial College London, said: “The world’s oceans have always been an important barometer when it comes to changes in our planet. Excitingly, the coral fossils we’ve studied are showing us that the North Atlantic Ocean at mid-depths was undergoing changes up to 1,000 years earlier than we had expected. The tantalising prospect is that this high variability may have been a signal that the last Ice Age was about to end.”

The fossil corals analysed by the team come from a species called Desmophyllum dianthus, which are often around 5cm in diameter and look like budding flowers. They typically only live for 100 years, giving the team a rare insight into what was happening to the ocean’s currents during this relatively brief time. Thousands of years ago they grew on the New England Seamounts, which are a chain of undersea mountains approximately 1000km off the east coast of the US, located at mid-depths 2km beneath the surface. This underwater area is important for understanding the North Atlantic’s currents.

While some of the corals analysed by the team come from historical collections, most have been collected by researchers from previous expeditions in 2003 and 2005 to the New England Seamounts. The researchers used deep sea robotic submergence vehicles called Hercules and Alvin to collect the ancient coral fossils.

These ancient coral fossils accumulated rare earth elements from seawater, including neodymium, which leached from rocks on land into the Atlantic Ocean and circulated in its currents, eventually ending up in the coral skeletons. Neodymium isotopes in different regions of the world have specific signatures, created by radioactive decay over billions of years. The scientists studied the chemistry of the coral fossils to determine where the neodymium isotopes had come from, giving them a glimpse into the circulation of the Atlantic Ocean at the end of the Ice Age.

Since the world’s oceans are connected by currents, the next step will see the team integrating the evidence they gathered from the North Atlantic Ocean into a picture of global changes in the mid-depths of oceans around the world. In particular, the team is interested in exploring how the Southern Ocean around Antarctica changed around the same time by analysing neodymium isotopes in a collection of Southern Ocean corals.

Imperial College London

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