At the end of the Pleistocene era, wooly mammoths roamed North America along with a cast of fantastic creatures – giant sloths, saber-toothed cats, camels, lions, tapirs and the incredible teratorn, a condor with a 16-foot wingspan.
About 12,900 years ago, these megafauna disappeared from the fossil record, as did evidence of human remains. The cause of the mass extinction and the human migration is a mystery. Now a team of scientists, including Brown University planetary geologist Peter Schultz, provides evidence that an asteroid impact likely caused the sudden climate changes that killed off the mammoths and other majestic beasts of prehistory.
In the Proceedings of the National Academy of Sciences, the international team lays out its theory that the mass extinctions in North America were caused by one or more extraterrestrial objects – comets or meteorites – that exploded over the Earth or slammed into it, triggering catastrophic climate change.
The scientists believe that evidence for these extraterrestrial impacts is hidden in a dark layer of dirt sometimes called a black mat. Found in more than 50 sites around North America, this puzzling slice of geological history is a mere three centimeters deep and filled with carbon, which lends the layer its dark color. This black mat has been found in archaeological digs in Canada and California, Arizona and South Carolina – even in a research site in Belgium.
The formation of this layer dates back 12,900 years and coincides with the abrupt cooling of the Younger Dryas period, sometimes called the “Big Freeze.” This coincidence intrigued the researchers, led by Richard Firestone of Lawrence Berkeley National Laboratory, who thought that the black mat might be related to the mass extinctions.
So the researchers studied black mat sediment samples from 10 archaeological sites dating back to the Clovis people, the first human inhabitants of the New World. Researchers conducted geochemical analysis of the samples to determine their makeup and also ran carbon dating tests to determine the age of the samples.
Directly beneath the black mat, researchers found high concentrations of magnetic grains containing iridium, charcoal, soot, carbon spherules, glass-like carbon containing nanodiamonds and fullerenes packed with extraterrestrial helium – all of which are evidence for an extraterrestrial impact and the raging wildfires that might have followed.
Schultz, professor of geological sciences at Brown and an impact specialist, said the most provocative evidence for an extraterrestrial impact was the discovery of nanodiamonds, microscopic bits of diamond formed only from the kind of intense pressure you’d get from a comet or meteorite slamming into the Earth.
“We don’t have a smoking gun for our theory, but we sure have a lot of shell casings,” Schultz said. “Taken together, the markers found in the samples offer intriguing evidence that North America had a major impact event about 12,900 years ago.”
Schultz admits that there is little decisive evidence about the actual details about the impact and its effects. Scientists suspect that a carbon-rich asteroid or comets were the culprits. The objects would have exploded over North America or slammed into it, or both, shattering and melting ice sheets, sparking extreme wildfires, and fueling hurricane-force winds – all of which could have contributed to changes in climate that led to the cooling of the Younger Dryas period.
“Our theory isn’t a slam dunk,” Schultz said. “We need to study a lot more sediments to get a lot more evidence. But what is sobering about this theory of ours is that this impact would be so recent. Not so long ago, something may have fallen from the sky and profoundly changed our climate and our culture.”
Tuesday, September 25, 2007
Monday, September 17, 2007
Sodom?
Archaeologist Steven Collins is directing a dig at a site he believes to be the infamous city of Sodom,
Collins, dean of the College of Archaeology at Trinity Southwest University in Albuquerque, N.M., has searched for a decade for Sodom and Gomorrah, which the Bible says were sinful cities destroyed by God. The excavation is of a Bronze Age site in Jordan, near the Dead Sea.
Collins is seeking to determine the authenticity of Old Testament patriarchal narratives, particularly the stories of Abraham, Isaac, Jacob, Joseph, Moses and Joshua.
He said findings of pottery and a mud-brick-and-earth rampart indicate that the city was destroyed in the Middle Bronze Age at about 2000 B.C., the time of Abraham and the story of the destruction of Sodom and Gomorrah. He is using biblical text, archaeology and geography in his quest.
www.findadig.com/collins
Collins, dean of the College of Archaeology at Trinity Southwest University in Albuquerque, N.M., has searched for a decade for Sodom and Gomorrah, which the Bible says were sinful cities destroyed by God. The excavation is of a Bronze Age site in Jordan, near the Dead Sea.
Collins is seeking to determine the authenticity of Old Testament patriarchal narratives, particularly the stories of Abraham, Isaac, Jacob, Joseph, Moses and Joshua.
He said findings of pottery and a mud-brick-and-earth rampart indicate that the city was destroyed in the Middle Bronze Age at about 2000 B.C., the time of Abraham and the story of the destruction of Sodom and Gomorrah. He is using biblical text, archaeology and geography in his quest.
www.findadig.com/collins
Wednesday, September 12, 2007
Role of climate in Neanderthal extinction
New evidence on the role of climate in Neanderthal extinction
THE mystery of what killed the Neanderthals has moved a step closer to resolution after an international study led by the University of Leeds has ruled out one of the competing theories – catastrophic climate change – as the most likely cause.
The bones of more than 400 Neanderthals have been found since the first discoveries were made in the early 19th century. The finds suggest the Neanderthals, named after the Neander Valley near Düsseldorf, where they were first recognized as an extinct kind of archaic humans, inhabited Europe and parts of western Asia for more than 100,000 years.
The causes of their extinction have puzzled scientists for years – with some believing it was due to competition with modern humans, while others blamed deteriorating climatic conditions. But a new study published today in Nature has shown that the Neanderthal extinction did not coincide with any of the extreme climate events that punctuated the last glacial period.
The research was led by Professor Chronis Tzedakis, a palaeoecologist at the University of Leeds, who explained: “Until now, there have been three limitations to understanding the role of climate in the Neanderthal extinction: uncertainty over the exact timing of their disappearance; uncertainties in converting radiocarbon dates to actual calendar years; and the chronological imprecision of the ancient climate record.”
The team’s novel method – mapping radiocarbon dates of interest directly onto a well-dated palaeoclimate archive – circumvented the last two problems, providing a much more detailed picture of the climate at the possible times of the Neanderthal disappearance.
The researchers applied the new method to three alternative sets of dates for the timing of the Neanderthal extinction from Gorham’s Cave, Gibraltar, a site which is thought to have been occupied by some of the latest surviving Neanderthals:
a set of generally accepted but older dates (around 30-32,000 radiocarbon years ago)
newly-suggested younger dates (around 28,000 radiocarbon years ago)
more contentious dates (around 24,000 radiocarbon years ago).
The team showed that during the first two sets of dates, Europe was experiencing conditions similar to the general climatic instability of the last glacial period – conditions the Neanderthals had already proved able to survive.
The much more controversial date of around 24,000 radiocarbon years ago placed the last Neanderthals just before a large expansion of ice sheets and the onset of cold conditions in northern Europe. “But at that time, Gibraltar’s climate remained relatively unaffected, perhaps as a result of warm water from the subtropical Atlantic entering the western Mediterranean,” explained palaeoceanographer Isabel Cacho of the University of Barcelona.
“Our findings suggest that there was no single climatic event that caused the extinction of the Neanderthals,” concludes palaeonthropologist Katerina Harvati of the Max Planck Institute for Evolutionary Anthropology. “Only the controversial date of 24,000 radiocarbon years for their disappearance, if proven correct, coincides with a major environmental shift. Even in this case, however, the role of climate would have been indirect, by promoting competition with other human groups.”
The work also has wider implications for other studies, as paleoclimatologist Konrad Hughen of the Woods Hole Oceanographic Institution explained: “Our approach offers the huge potential to unravel the role of climate in critical events of the recent fossil record as it can be applied to any radiocarbon date from any deposit.”
THE mystery of what killed the Neanderthals has moved a step closer to resolution after an international study led by the University of Leeds has ruled out one of the competing theories – catastrophic climate change – as the most likely cause.
The bones of more than 400 Neanderthals have been found since the first discoveries were made in the early 19th century. The finds suggest the Neanderthals, named after the Neander Valley near Düsseldorf, where they were first recognized as an extinct kind of archaic humans, inhabited Europe and parts of western Asia for more than 100,000 years.
The causes of their extinction have puzzled scientists for years – with some believing it was due to competition with modern humans, while others blamed deteriorating climatic conditions. But a new study published today in Nature has shown that the Neanderthal extinction did not coincide with any of the extreme climate events that punctuated the last glacial period.
The research was led by Professor Chronis Tzedakis, a palaeoecologist at the University of Leeds, who explained: “Until now, there have been three limitations to understanding the role of climate in the Neanderthal extinction: uncertainty over the exact timing of their disappearance; uncertainties in converting radiocarbon dates to actual calendar years; and the chronological imprecision of the ancient climate record.”
The team’s novel method – mapping radiocarbon dates of interest directly onto a well-dated palaeoclimate archive – circumvented the last two problems, providing a much more detailed picture of the climate at the possible times of the Neanderthal disappearance.
The researchers applied the new method to three alternative sets of dates for the timing of the Neanderthal extinction from Gorham’s Cave, Gibraltar, a site which is thought to have been occupied by some of the latest surviving Neanderthals:
a set of generally accepted but older dates (around 30-32,000 radiocarbon years ago)
newly-suggested younger dates (around 28,000 radiocarbon years ago)
more contentious dates (around 24,000 radiocarbon years ago).
The team showed that during the first two sets of dates, Europe was experiencing conditions similar to the general climatic instability of the last glacial period – conditions the Neanderthals had already proved able to survive.
The much more controversial date of around 24,000 radiocarbon years ago placed the last Neanderthals just before a large expansion of ice sheets and the onset of cold conditions in northern Europe. “But at that time, Gibraltar’s climate remained relatively unaffected, perhaps as a result of warm water from the subtropical Atlantic entering the western Mediterranean,” explained palaeoceanographer Isabel Cacho of the University of Barcelona.
“Our findings suggest that there was no single climatic event that caused the extinction of the Neanderthals,” concludes palaeonthropologist Katerina Harvati of the Max Planck Institute for Evolutionary Anthropology. “Only the controversial date of 24,000 radiocarbon years for their disappearance, if proven correct, coincides with a major environmental shift. Even in this case, however, the role of climate would have been indirect, by promoting competition with other human groups.”
The work also has wider implications for other studies, as paleoclimatologist Konrad Hughen of the Woods Hole Oceanographic Institution explained: “Our approach offers the huge potential to unravel the role of climate in critical events of the recent fossil record as it can be applied to any radiocarbon date from any deposit.”
Tuesday, September 4, 2007
Pigs brought to Europe by early farmers
Pig study sheds new light on the colonisation of Europe by early farmers
The earliest domesticated pigs in Europe, which many archaeologists believed to be descended from European wild boar, were actually introduced from the Middle East by Stone Age farmers, new research suggests.
The research by an international team led by archaeologists at Durham University, which is published today in the academic journal Proceedings of the National Academies of Sciences USA, analysed mitochondrial DNA from ancient and modern pig remains. Its findings also suggest that the migration of an expanding Middle Eastern population, who brought their ‘farming package’ of domesticated plants, animals and distinctive pottery styles with them, actually ‘kickstarted’ the local domestication of the European wild boar.
While archaeologists already know that agriculture began about 12,000 years ago in the central and western parts of the Middle East, spreading rapidly across Europe between 6,800 – 4000BC, many outstanding questions remain about the mechanisms of just how it spread. This research sheds new and important light on the actual process of the establishment of farming in Europe.
Durham University’s Dr Keith Dobney explained: “Many archaeologists believe that farming spread through the diffusion of ideas and cultural exchange, not with the direct migration of people. However, the discovery and analysis of ancient Middle Eastern pig remains across Europe reveals that although cultural exchange did happen, Europe was definitely colonised by Middle Eastern farmers.
“A combination of rising population and possible climate change in the ‘fertile crescent’, which put pressure on land and resources, made them look for new places to settle, plant their crops and breed their animals and so they rapidly spread west into Europe.”
The research, funded by the Wellcome Trust, the Leverhulme Trust, the Arts and Humanities Research Council (AHRC) and the Smithsonian Institution also showed that within 500 years after the local domestication of the European wild boar, the new domestics completely replaced the Middle Eastern pigs that had arrived in Europe as part of the ‘farming package’.
Dr Greger Larson, who performed the genetic analysis said: “The domestic pigs that were derived from the European wild boar must have been considered vastly superior to those originally from Middle East, though at this point we have no idea why. In fact, the European domestic pigs were so successful that over the next several thousand years they spread across the continent and even back into the Middle East where they overtook the indigenous domestic pigs. For whatever reason, European pigs were the must have farm animal.”
The research is part of an ongoing research project based at Durham University which explores the role of animals in reconstructing early farming, ancient human migration and past trade and exchange networks around the world.
The earliest domesticated pigs in Europe, which many archaeologists believed to be descended from European wild boar, were actually introduced from the Middle East by Stone Age farmers, new research suggests.
The research by an international team led by archaeologists at Durham University, which is published today in the academic journal Proceedings of the National Academies of Sciences USA, analysed mitochondrial DNA from ancient and modern pig remains. Its findings also suggest that the migration of an expanding Middle Eastern population, who brought their ‘farming package’ of domesticated plants, animals and distinctive pottery styles with them, actually ‘kickstarted’ the local domestication of the European wild boar.
While archaeologists already know that agriculture began about 12,000 years ago in the central and western parts of the Middle East, spreading rapidly across Europe between 6,800 – 4000BC, many outstanding questions remain about the mechanisms of just how it spread. This research sheds new and important light on the actual process of the establishment of farming in Europe.
Durham University’s Dr Keith Dobney explained: “Many archaeologists believe that farming spread through the diffusion of ideas and cultural exchange, not with the direct migration of people. However, the discovery and analysis of ancient Middle Eastern pig remains across Europe reveals that although cultural exchange did happen, Europe was definitely colonised by Middle Eastern farmers.
“A combination of rising population and possible climate change in the ‘fertile crescent’, which put pressure on land and resources, made them look for new places to settle, plant their crops and breed their animals and so they rapidly spread west into Europe.”
The research, funded by the Wellcome Trust, the Leverhulme Trust, the Arts and Humanities Research Council (AHRC) and the Smithsonian Institution also showed that within 500 years after the local domestication of the European wild boar, the new domestics completely replaced the Middle Eastern pigs that had arrived in Europe as part of the ‘farming package’.
Dr Greger Larson, who performed the genetic analysis said: “The domestic pigs that were derived from the European wild boar must have been considered vastly superior to those originally from Middle East, though at this point we have no idea why. In fact, the European domestic pigs were so successful that over the next several thousand years they spread across the continent and even back into the Middle East where they overtook the indigenous domestic pigs. For whatever reason, European pigs were the must have farm animal.”
The research is part of an ongoing research project based at Durham University which explores the role of animals in reconstructing early farming, ancient human migration and past trade and exchange networks around the world.
First beehives in ancient Near East excavated
Archaeological proof of the Biblical description of Israel really as “the land of milk and honey” (or at least the latter) has been uncovered by researchers from the Hebrew University of Jerusalem Institute of Archaeology.
Amihai Mazar, Eleazar L. Sukenik Professor of Archaeology at the Hebrew University, revealed that the first apiary (beehive colony) dating from the Biblical period has been found in excavations he directed this summer at Tel Rehov in Israel’s Beth Shean Valley. This is the earliest apiary to be revealed to date in an archaeological excavation anywhere in the ancient Near East, said Prof. Mazar. It dates from the 10th to early 9th centuries B.C.E.
Tel Rehov is believed to have been one of the most important cities of Israel during the Israelite monarchy. The beehives there were found in the center of a built-up area there that has been excavated since 1997 by Dr. Nava Panitz-Cohen of the Hebrew University. Three rows of beehives were found in the apiary, containing more than 30 hives. It is estimated, however, based on excavations to date, that in all the total area would have contained some 100 beehives.
Each row contained at least three tiers of hives, each of which is a cylinder composed of unbaked clay and dry straw, around 80 centimeters long and 40 centimeters in diameter. One end of the cylinder was closed and had a small hole in it, which allowed for the entry and exit of the bees. The opposite end was covered with a clay lid that could be removed when the beekeeper extracted the honeycombs. Experienced beekeepers and scholars who visited the site estimated that as much as half a ton of honey could be culled each year from these hives.
Prof. Mazar emphasizes the uniqueness of this latest find by pointing out that actual beehives have never been discovered at any site in the ancient Near East. While fired ceramic vessels that served as beehives are known in the Hellenistic and Roman periods, none were found in situ, and beekeeping on an industrial level such as the apiary at Tel Rehov is hitherto unknown in the archaeological record. Pictorial depictions of apiaries are known from Pharaonic Egypt, showing extraction of honey from stacked cylinders which are very similar to those found at Tel Rehov.
Cylindrical clay beehives placed in horizontal rows, similar to those found at Tel Rehov, are well-known in numerous contemporary traditional cultures in Arab villages in Israel, as well as throughout the Mediterranean. The various products of beehives are put to diverse use: the honey is, of course, a delicacy, but is also known for its medicinal and cultic value. Beeswax was also utilized in the metal and leather industries, as well as for writing material when coated on wooden tablets.
The term “honey” appears 55 times in the Bible, 16 of which as part of the image of Israel as “the land of milk and honey”. It is commonly believed that the term refers to honey produced from fruits such as dates and figs. Bees’ honey, on the other hand, is mentioned explicitly only twice, both related to wild bees. The first instance is how Samson culled bees’ honey from inside the corpse of the lion in the Soreq Valley (Judges 14: 8-9). The second case is the story of Jonathan, King Saul’s son, who dipped his hand into a honeycomb during the battle of Mikhmash (Samuel I 14:27).
While the Bible tells us nothing about beekeeping in Israel at that time, the discovery of the apiary at Tel Rehov indicates that beekeeping and the extraction of bees’ honey and honeycomb was a highly developed industry as early as the First Temple period. Thus, it is possible that the term “honey” in the Bible indeed pertains to bees’ honey.
Cultic objects were also found in the apiary, including a four-horned altar adorned with figures of naked fertility goddesses, as well as an elaborately painted chalice. This could be evidence of deviant cultic practices by the ancient Israelites related to the production of honey and beeswax.
Study of the beehives found at Tel Rehov is being conducted with the participation of various researchers. Dr. Guy Bloch of the Silberman Institute of Life Sciences of the Hebrew University is studying the biological aspects of the finds; he already discovered parts of bees’ bodies in the remains of honeycomb extracted from inside the hives. Dr. Dvori Namdar of the Weizmann Institute of Science succeeded in identifying beeswax molecules from the walls of the beehives, and Prof. Mina Evron from Haifa University is analyzing the pollen remains in the hives.
Dating of the beehives was done by measuring the decaying of the 14C isotope in organic materials, using grains of wheat found next to the beehives. This grain was dated at the laboratory of Groningen University in Holland to the period between the mid-10th century B.C.E. until the early 9th century B.C.E. This is the time period attributed to the reign of King Solomon and the first kings of the northern Kingdom of Israel following the division of the monarchy. The city of Rehov is indeed mentioned in an Egyptian inscription dating to the time of the Pharaoh Shoshenq I (Biblical Shishak), whom the Bible notes as the contemporary of King Solomon and who invaded Israel following that monarch’s death.
A particularly fascinating find at the site is an inscription on a ceramic storage jar found near the beehives that reads “To nmsh”. This name was also found inscribed on another storage jar from a slightly later occupation level at Tel Rehov, dated to the time of the Omride Dynasty in the 9th century BCE. Moreover, this same name was found on a contemporary jar from nearby Tel Amal, situated in the Gan HaShelosha National Park (Sachne).
The name “Nimshi” is known in the Bible as the name of the father and in several verses the grandfather of Israelite King Jehu, the founder of the dynasty that usurped power from the Omrides (II Kings: 9-12). It is possible that the discovery of three inscriptions bearing this name in the same region and dating to the same period indicates that Jehu’s family originated from the Beth Shean Valley and possibly even from the large city located at Tel Rehov. The large apiary discovered at the site might have belonged to this illustrious local clan.
Amihai Mazar, Eleazar L. Sukenik Professor of Archaeology at the Hebrew University, revealed that the first apiary (beehive colony) dating from the Biblical period has been found in excavations he directed this summer at Tel Rehov in Israel’s Beth Shean Valley. This is the earliest apiary to be revealed to date in an archaeological excavation anywhere in the ancient Near East, said Prof. Mazar. It dates from the 10th to early 9th centuries B.C.E.
Tel Rehov is believed to have been one of the most important cities of Israel during the Israelite monarchy. The beehives there were found in the center of a built-up area there that has been excavated since 1997 by Dr. Nava Panitz-Cohen of the Hebrew University. Three rows of beehives were found in the apiary, containing more than 30 hives. It is estimated, however, based on excavations to date, that in all the total area would have contained some 100 beehives.
Each row contained at least three tiers of hives, each of which is a cylinder composed of unbaked clay and dry straw, around 80 centimeters long and 40 centimeters in diameter. One end of the cylinder was closed and had a small hole in it, which allowed for the entry and exit of the bees. The opposite end was covered with a clay lid that could be removed when the beekeeper extracted the honeycombs. Experienced beekeepers and scholars who visited the site estimated that as much as half a ton of honey could be culled each year from these hives.
Prof. Mazar emphasizes the uniqueness of this latest find by pointing out that actual beehives have never been discovered at any site in the ancient Near East. While fired ceramic vessels that served as beehives are known in the Hellenistic and Roman periods, none were found in situ, and beekeeping on an industrial level such as the apiary at Tel Rehov is hitherto unknown in the archaeological record. Pictorial depictions of apiaries are known from Pharaonic Egypt, showing extraction of honey from stacked cylinders which are very similar to those found at Tel Rehov.
Cylindrical clay beehives placed in horizontal rows, similar to those found at Tel Rehov, are well-known in numerous contemporary traditional cultures in Arab villages in Israel, as well as throughout the Mediterranean. The various products of beehives are put to diverse use: the honey is, of course, a delicacy, but is also known for its medicinal and cultic value. Beeswax was also utilized in the metal and leather industries, as well as for writing material when coated on wooden tablets.
The term “honey” appears 55 times in the Bible, 16 of which as part of the image of Israel as “the land of milk and honey”. It is commonly believed that the term refers to honey produced from fruits such as dates and figs. Bees’ honey, on the other hand, is mentioned explicitly only twice, both related to wild bees. The first instance is how Samson culled bees’ honey from inside the corpse of the lion in the Soreq Valley (Judges 14: 8-9). The second case is the story of Jonathan, King Saul’s son, who dipped his hand into a honeycomb during the battle of Mikhmash (Samuel I 14:27).
While the Bible tells us nothing about beekeeping in Israel at that time, the discovery of the apiary at Tel Rehov indicates that beekeeping and the extraction of bees’ honey and honeycomb was a highly developed industry as early as the First Temple period. Thus, it is possible that the term “honey” in the Bible indeed pertains to bees’ honey.
Cultic objects were also found in the apiary, including a four-horned altar adorned with figures of naked fertility goddesses, as well as an elaborately painted chalice. This could be evidence of deviant cultic practices by the ancient Israelites related to the production of honey and beeswax.
Study of the beehives found at Tel Rehov is being conducted with the participation of various researchers. Dr. Guy Bloch of the Silberman Institute of Life Sciences of the Hebrew University is studying the biological aspects of the finds; he already discovered parts of bees’ bodies in the remains of honeycomb extracted from inside the hives. Dr. Dvori Namdar of the Weizmann Institute of Science succeeded in identifying beeswax molecules from the walls of the beehives, and Prof. Mina Evron from Haifa University is analyzing the pollen remains in the hives.
Dating of the beehives was done by measuring the decaying of the 14C isotope in organic materials, using grains of wheat found next to the beehives. This grain was dated at the laboratory of Groningen University in Holland to the period between the mid-10th century B.C.E. until the early 9th century B.C.E. This is the time period attributed to the reign of King Solomon and the first kings of the northern Kingdom of Israel following the division of the monarchy. The city of Rehov is indeed mentioned in an Egyptian inscription dating to the time of the Pharaoh Shoshenq I (Biblical Shishak), whom the Bible notes as the contemporary of King Solomon and who invaded Israel following that monarch’s death.
A particularly fascinating find at the site is an inscription on a ceramic storage jar found near the beehives that reads “To nmsh”. This name was also found inscribed on another storage jar from a slightly later occupation level at Tel Rehov, dated to the time of the Omride Dynasty in the 9th century BCE. Moreover, this same name was found on a contemporary jar from nearby Tel Amal, situated in the Gan HaShelosha National Park (Sachne).
The name “Nimshi” is known in the Bible as the name of the father and in several verses the grandfather of Israelite King Jehu, the founder of the dynasty that usurped power from the Omrides (II Kings: 9-12). It is possible that the discovery of three inscriptions bearing this name in the same region and dating to the same period indicates that Jehu’s family originated from the Beth Shean Valley and possibly even from the large city located at Tel Rehov. The large apiary discovered at the site might have belonged to this illustrious local clan.
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