Eight miles south of Jerusalem, where the last stunted olive trees and stony cornfields fade into the naked badlands of the Judaean desert, a hill rises abruptly, a steep cone sliced off at the top like a small volcano. This is Herodium, one of the grand architectural creations of Herod the Great, King of Judaea, who raised a low knoll into a towering memorial of snowy stonework and surrounded it with pleasure palaces, splashing pools, and terraced gardens. An astute and generous ruler, a brilliant general, and one of the most imaginative and energetic builders of the ancient world, Herod guided his kingdom to new prosperity and power. Yet today he is best known as the sly and murderous monarch of Matthew's Gospel, who slaughtered every male infant in Bethlehem in an unsuccessful attempt to kill the newborn Jesus, the prophesied King of the Jews. During the Middle Ages he became an image of the Antichrist: Illuminated manuscripts and Gothic gargoyles show him tearing his beard in mad fury and brandishing his sword at the luckless infants, with Satan whispering in his ear. Herod is almost certainly innocent of this crime, of which there is no report apart from Matthew's account. But children he certainly slew, including three of his own sons, along with his wife, his mother-in-law, and numerous other members of his court. Throughout his life, he blended creativity and cruelty, harmony and chaos, in ways that challenge the modern imagination.
Israeli archaeologist Ehud Netzer has spent the past half century searching for the real Herod, as he is portrayed not in words but in stone. He has excavated many of Herod's major building sites throughout the Holy Land, exploring the palaces where the king lived, the fortresses where he fought, the landscapes where he felt most at home. Of Herod's many imaginative building projects, Herodium was the only one that bore his name, and was perhaps the closest to his heart. It was here, at the end of his daring and bloodstained career, that he was laid to rest in a noble mausoleum.
The precise location of Herod's tomb remained a mystery for nearly two millennia, until April 2007, when Netzer and his colleagues at the Hebrew University in Jerusalem unearthed it on the upper slopes of Herodium. The discovery provided new insights into one of the most enigmatic minds of the ancient world—and fresh evidence of the hatred that Herod excited among his contemporaries. It also became a political incident, with Palestinians arguing that the artifacts at the site belonged to them, and Jewish settlers saying that the tomb's presence strengthened their claim to the West Bank. To Netzer, whose work at various Herodian sites has for decades been interrupted by war, invasion, and uprisings, the controversy was hardly surprising. In the Holy Land, archaeology can be as political as kingship.
Herod was born in 73 B.C. and grew up in Judaea, a kingdom in the heart of ancient Palestine that was torn by civil war and caught between powerful enemies. The Hasmonaean monarchy that had ruled Judaea for 70 years was split by a vicious fight for the throne between two princely brothers, Hyrcanus II and Aristobulus II. The kingdom was in turn caught in a larger geopolitical struggle between the Roman legions to the north and west, and the Parthians, historic enemies of Rome, to the east. Herod's father, the chief adviser to Hyrcanus and a gifted general, threw in his lot with the Romans, who banished Aristobulus and made Hyrcanus king of Judaea.
From boyhood, Herod saw the benefits of entente with the Roman overlords—a stance that has long been judged a betrayal of the Jewish people—and it was the Romans who would eventually make Herod king. Throughout his career he strove to reconcile their demands with those of his Jewish subjects, who jealously guarded their political and religious independence. Maintaining this delicate balance was all the more difficult because of Herod's background; his mother was an ethnic Arab, and his father was an Edomite, and though Herod was raised as a Jew, he lacked the social status of the powerful old families in Jerusalem who were eligible to serve as high priest, as the Hasmonaean kings had traditionally done. Many of his subjects considered Herod an outsider—a "half Jew," as his early biographer, the Jewish soldier and aristocrat Flavius Josephus later wrote—and continued to fight for a Hasmonaean theocracy. In 43 B.C., Herod's father was poisoned by a Hasmonaean agent. Three years later, when the Parthians suddenly invaded Judaea, a rival Hasmonaean faction allied themselves with the invaders, deposed and mutilated Hyrcanus, and turned on Herod.
In this moment of crisis, Herod looked to the Romans for help. He fled Jerusalem with his family under cover of darkness, and after defeating the Parthians and their Jewish allies in a desperate battle at the site where he would later build Herodium, he traveled on to Rome, where the senate, remembering his unswerving loyalty, named him King of Judaea. He walked out of the senate building arm in arm with the two most powerful men in the Roman world: Mark Antony, the soldier and orator who ruled the Roman east, and Octavian, the young patrician who ruled the west, and who, nine years later, would defeat Antony and assume command of the entire empire, subsequently taking the title "Augustus." Then, in an act that symbolized the many accommodations he would have to make to keep his slippery grip on power, Herod led the procession up the Capitoline Hill to the Temple of Jove, Rome's most sacred shrine, and there the King of Judaea offered sacrifice to the gods of pagan Rome.
Now Herod had his kingdom, but he still had to conquer it, which took three years of hard fighting. Finally, in 37 B.C., he captured Jerusalem, and Judaea was his—at least politically. To bolster his social and religious authority, he divorced his first wife, Doris, and married Mariamne, a Hasmonaean princess. But the Hasmonaean threat remained. Two years later, at Passover, Mariamne's teenage brother, the high priest in the Second Temple, received a warm ovation from the crowds of worshippers; Herod, fearing that the young man might one day usurp his throne, had him drowned in a swimming pool in his palace in Jericho.
The Hasmonaeans were not his only concern. From 42 to 31 B.C., while Mark Antony ruled the Roman east, Herod remained his staunch friend and ally, despite the ambitions of AnÂtony's beautiful Egyptian queen, Cleopatra, who persuaded her love-struck husband to carve out choice portions of Herod's kingdom for her, and even tried to seduce Herod. (He declined her advances.) In 31 B.C., the political landscape was transformed by the Battle of Actium, during which Octavian crushed the combined armies of Antony and Cleopatra and became the first emperor of Rome. Herod, knowing that Octavian would take a dim view of his long-standing friendship with Antony, rushed to the island of Rhodes to meet the emperor and presented himself without his crown, but with all of his kingly dignity. Instead of downplaying his devotion to Antony, he underscored it and promised to serve his new master, Octavian, with the same loyalty in the future. Octavian was so impressed by Herod's frankness and poise that he confirmed him as King of Judaea, and later added other territories to his realm, saying that Herod's megalopsychia—his greatness of spirit—was too large to fit a small kingdom like Judaea.
In the two decades of economic prosperity and relative peace that followed, Herod made his court a hotbed of Hellenistic and Roman culture, gathering around him some of the leading scholars, poets, sculptors, painters, and architects of the east and west. He gave with kingly generosity, to his own subjects in times of famine and natural disaster, and far beyond the boundaries of his kingdom, in Greece and Asia Minor. (The citizens of Olympia were so grateful for his lavish donations that they elected him agonothete, or president, of the Olympic Games.) And he undertook building projects of remarkable scope, ambition, and creativity. Since the north coast of Judaea lacked a natural deepwater harbor, he built one from scratch at Caesarea, using an innovative building technique to make an enormous breakwater from massive blocks of hydraulic concrete. Herod's Northern Palace at Masada cascades breathtakingly down a cliff face on three narrow terraces, creating an airy and luminous residence that was also a virtually impregnable fortress. In rebuilding the Second Temple, Herod used gargantuan foundation stones, some over 40 feet long and weighing 600 tons. What remains of this stonework, the Western Wall, is Judaism's most sacred place. Upon it rests Islam's third holiest site, the Dome of the Rock.
The outward grandeur and prosperity of Herod's reign concealed the increasing turbulence of his private life. Like many Hellenistic rulers of his time, he had a large and fractious family—ten wives and more than a dozen children—whose frequent conspiracies brought out Herod's cruelty and paranoia. In 29 B.C., in a blaze of jealousy deftly stoked by his sister Salome, he executed his wife Mariamne, though he still loved her deeply, and lived for months afterward in blackest depression, calling her name as if to summon her back from the dead. In his later years he dispatched three of his sons for alleged conspiracies to overthrow him, and redrew his will six times. During his last illness he devised a scheme to plunge the entire kingdom into mourning when he died, ordering his army to imprison a crowd of leading Judaean citizens in the hippodrome in Jericho, and to massacre them when his death was announced. (Fortunately for these well-heeled Judaeans, his command was not carried out.)
Wednesday, January 7, 2009
DNA tracks ancient Alaskan's descendants
10,300 YEARS OLD: Tests of Southeast Natives challenge prior anthropological results.
An ancient mariner who lived and died 10,000 years ago on an island west of Ketchikan probably doesn't have any close relatives left in Alaska.
But some of them migrated south and their descendents can be found today in coastal Native American populations in California, Mexico, Ecuador, Chile and Argentina.
That's some of what scientists learned this summer by examining the DNA of Tlingit, Haida and Tsimshian Indians in Southeast Alaska.
Working with elders at a cultural festival in Juneau, they interviewed more than 200 Native Alaskans who allowed them to swab tiny amounts of saliva from their cheeks to capture their mitochondrial DNA, the genetic material that's passed from mothers to children.
Preliminary examination of those cell particles indicates:
• None of the participants possessed DNA similar to that extracted from On Your Knees Cave man, the 10,300-year-old Alaskan whose remains were discovered 12 years ago in a shallow cavern on Prince of Wales Island.
• But some participants appear to be closely linked genetically to coastal Indian tribes in British Columbia and Washington state, in spite of anthropological studies that claim Tlingits were originally an Interior people, like the nearby Athabascans.
"We haven't seen connections inland yet ... looking at just the very first couple of samples," said Washington State University Assistant Professor Brian Kemp, the molecular anthropologist who led the research. "That doesn't mean we won't. But right now we only have these long-distant connections."
ADVERTISEMENT
Apparently On Your Knees Cave man only has long-distant relatives too.
AN ANCIENT TRAVELER
Bones of the ancient Alaskan were first discovered in 1996 by Alaska paleontologist Tim Heaton during an archaeological survey on the northern tip of Prince of Wales, the nation's third largest island.
They are among the oldest human remains ever found in North America -- a 13,000-year-old woman's partial skeleton was discovered 50 years ago in an island cave off the south coast of California -- and the oldest ever discovered in Alaska.
Heaton's team recovered a male pelvis, three ribs, a few vertebrae and a toothy, broken jaw, along with some ancient tools. With the help of archaeologist E. James Dixon, they eventually pieced together the caveman's story.
His teeth indicate he died in his prime, possibly in his early to mid-20s. The content of his bones revealed that his primary food came from the sea. The nearby stone tools, consisting of materials not found on the island, suggest a long-distance traveler, a mariner.
Then the geneticists went to work. Laboring two years as a graduate student, Kemp finally succeeded in extracting mitochondrial DNA from one of the caveman's teeth, the oldest DNA sample ever recovered in the Americas at the time.
It clearly placed On Your Knees Cave man in the "haplogroup-D" branch of the human family tree.
GENETIC TRAILS
Population geneticists trace all humans alive today back to common ancestors who lived in Africa about 60,000 years ago. As they migrated north out of Africa, then east and west across Asia and Europe, the common DNA they carried with them would occasionally mutate.
Different populations that migrated to different destinations carried different sets of mutations, which scientists have categorized into haplogroups and sub-haplogroups. The first people to migrate to the Americas all belonged to one of five primary haplogroups: A, B, C, D or X.
Just knowing that On Your Knees Cave man was a D reduced the chances that he would have any close relatives still living among present-day Native Alaskans, Kemp said. Previous DNA sampling of Eskimos, Athabaskans and Southeast Indians had traced nearly all of them to haplogroup A, with a tiny scattering of Bs.
The only known haplogroup D people in Alaska were the Aleuts. But that made them only distant relatives to On Your Knees Cave man -- very distant, since scientists believe the D mutation appeared for the first time about 50,000 years ago in Asia.
On closer inspection, however, Kemp found that On Your Knees Cave man belonged more specifically to the genetic sub-group D4H3, which may have shown up as recently as 20,000 years ago. Still, it's an exclusive group. Less than 2 percent of all Native Americans share that signature.
Aleuts living today don't appear to be that closely related to the caveman, Kemp said. Of the 163 tested so far, none were D4H3.
"The Aleuts are more closely related to the On Your Knees Cave individual than anyone who is not a member of D," he said. "But that has nothing to do with what happened in the Americas. It happened way before."
According to Kemp's research, part of what happened in the Americas is this:
Some of the caveman's relatives decided to head south from Alaska. Members of his specific genetic lineage have been found among the Chumash people of Southern California, the Cayapa of Ecuador and the Yaghan of Tierra del Fuego.
The fact that most of them landed at seaside destinations lends a lot more credence to scientists who believe the Lower 48 states and South America were populated first by coastal mariners -- Ice Age migrants from Asia who skirted around land-blocking glaciers in Alaska as early as 20,000 years ago
TLINGIT MYSTERY
Did some of those first Alaskans remain behind in the North? In terms of present-day Native Alaskans who might share the same specific genetic marker as On Your Knees Cave man, the jury is still out, Kemp said.
That's because genetic genealogy is still in its infancy. Very few Native Americans have been checked so far.
The DNA testing of 234 Southeast Alaska Indians that occurred in June -- one of the largest samples ever collected in the Americas -- nearly doubled all the previous data scientists had on Alaska Native populations, Kemp said.
It's possible the right person with the right match simply hasn't been tested yet, said Rosita Worl, president of the Sealaska Heritage Institute, the nonprofit Southeast Alaska Native group that sponsored the research.
It's also possible that the Tlingits and Haidas -- migrating either from the south or the Interior -- arrived in Southeast Alaska after the cave man's people had already passed through.
Worl's research suggests that the Tlingits of today used to be two separate populations. Tlingit society has long been divided between two groups, called "moieties" -- the Eagles and the Ravens -- based on the mother's ancestry. It's possible that one group preceded the other.
"Our oral traditions always talk about the presence of an older population being here when they arrived," said Worl, a Juneau-based Tlingit who teaches cultural anthropology at the University of Alaska Southeast.
"The hypothesis is that the Eagles and the Ravens represent two different populations."
Kemp is anxious to continue his research on his Tlingit DNA samples, to see if the matrilineal branches based on DNA match the matrilineal branches based on culture.
"We collected as much information as we could about individual moieties," Kemp said. "So a cool test will be to see if it (matches) the population genetics. And that may clarify the separate origins."
An ancient mariner who lived and died 10,000 years ago on an island west of Ketchikan probably doesn't have any close relatives left in Alaska.
But some of them migrated south and their descendents can be found today in coastal Native American populations in California, Mexico, Ecuador, Chile and Argentina.
That's some of what scientists learned this summer by examining the DNA of Tlingit, Haida and Tsimshian Indians in Southeast Alaska.
Working with elders at a cultural festival in Juneau, they interviewed more than 200 Native Alaskans who allowed them to swab tiny amounts of saliva from their cheeks to capture their mitochondrial DNA, the genetic material that's passed from mothers to children.
Preliminary examination of those cell particles indicates:
• None of the participants possessed DNA similar to that extracted from On Your Knees Cave man, the 10,300-year-old Alaskan whose remains were discovered 12 years ago in a shallow cavern on Prince of Wales Island.
• But some participants appear to be closely linked genetically to coastal Indian tribes in British Columbia and Washington state, in spite of anthropological studies that claim Tlingits were originally an Interior people, like the nearby Athabascans.
"We haven't seen connections inland yet ... looking at just the very first couple of samples," said Washington State University Assistant Professor Brian Kemp, the molecular anthropologist who led the research. "That doesn't mean we won't. But right now we only have these long-distant connections."
ADVERTISEMENT
Apparently On Your Knees Cave man only has long-distant relatives too.
AN ANCIENT TRAVELER
Bones of the ancient Alaskan were first discovered in 1996 by Alaska paleontologist Tim Heaton during an archaeological survey on the northern tip of Prince of Wales, the nation's third largest island.
They are among the oldest human remains ever found in North America -- a 13,000-year-old woman's partial skeleton was discovered 50 years ago in an island cave off the south coast of California -- and the oldest ever discovered in Alaska.
Heaton's team recovered a male pelvis, three ribs, a few vertebrae and a toothy, broken jaw, along with some ancient tools. With the help of archaeologist E. James Dixon, they eventually pieced together the caveman's story.
His teeth indicate he died in his prime, possibly in his early to mid-20s. The content of his bones revealed that his primary food came from the sea. The nearby stone tools, consisting of materials not found on the island, suggest a long-distance traveler, a mariner.
Then the geneticists went to work. Laboring two years as a graduate student, Kemp finally succeeded in extracting mitochondrial DNA from one of the caveman's teeth, the oldest DNA sample ever recovered in the Americas at the time.
It clearly placed On Your Knees Cave man in the "haplogroup-D" branch of the human family tree.
GENETIC TRAILS
Population geneticists trace all humans alive today back to common ancestors who lived in Africa about 60,000 years ago. As they migrated north out of Africa, then east and west across Asia and Europe, the common DNA they carried with them would occasionally mutate.
Different populations that migrated to different destinations carried different sets of mutations, which scientists have categorized into haplogroups and sub-haplogroups. The first people to migrate to the Americas all belonged to one of five primary haplogroups: A, B, C, D or X.
Just knowing that On Your Knees Cave man was a D reduced the chances that he would have any close relatives still living among present-day Native Alaskans, Kemp said. Previous DNA sampling of Eskimos, Athabaskans and Southeast Indians had traced nearly all of them to haplogroup A, with a tiny scattering of Bs.
The only known haplogroup D people in Alaska were the Aleuts. But that made them only distant relatives to On Your Knees Cave man -- very distant, since scientists believe the D mutation appeared for the first time about 50,000 years ago in Asia.
On closer inspection, however, Kemp found that On Your Knees Cave man belonged more specifically to the genetic sub-group D4H3, which may have shown up as recently as 20,000 years ago. Still, it's an exclusive group. Less than 2 percent of all Native Americans share that signature.
Aleuts living today don't appear to be that closely related to the caveman, Kemp said. Of the 163 tested so far, none were D4H3.
"The Aleuts are more closely related to the On Your Knees Cave individual than anyone who is not a member of D," he said. "But that has nothing to do with what happened in the Americas. It happened way before."
According to Kemp's research, part of what happened in the Americas is this:
Some of the caveman's relatives decided to head south from Alaska. Members of his specific genetic lineage have been found among the Chumash people of Southern California, the Cayapa of Ecuador and the Yaghan of Tierra del Fuego.
The fact that most of them landed at seaside destinations lends a lot more credence to scientists who believe the Lower 48 states and South America were populated first by coastal mariners -- Ice Age migrants from Asia who skirted around land-blocking glaciers in Alaska as early as 20,000 years ago
TLINGIT MYSTERY
Did some of those first Alaskans remain behind in the North? In terms of present-day Native Alaskans who might share the same specific genetic marker as On Your Knees Cave man, the jury is still out, Kemp said.
That's because genetic genealogy is still in its infancy. Very few Native Americans have been checked so far.
The DNA testing of 234 Southeast Alaska Indians that occurred in June -- one of the largest samples ever collected in the Americas -- nearly doubled all the previous data scientists had on Alaska Native populations, Kemp said.
It's possible the right person with the right match simply hasn't been tested yet, said Rosita Worl, president of the Sealaska Heritage Institute, the nonprofit Southeast Alaska Native group that sponsored the research.
It's also possible that the Tlingits and Haidas -- migrating either from the south or the Interior -- arrived in Southeast Alaska after the cave man's people had already passed through.
Worl's research suggests that the Tlingits of today used to be two separate populations. Tlingit society has long been divided between two groups, called "moieties" -- the Eagles and the Ravens -- based on the mother's ancestry. It's possible that one group preceded the other.
"Our oral traditions always talk about the presence of an older population being here when they arrived," said Worl, a Juneau-based Tlingit who teaches cultural anthropology at the University of Alaska Southeast.
"The hypothesis is that the Eagles and the Ravens represent two different populations."
Kemp is anxious to continue his research on his Tlingit DNA samples, to see if the matrilineal branches based on DNA match the matrilineal branches based on culture.
"We collected as much information as we could about individual moieties," Kemp said. "So a cool test will be to see if it (matches) the population genetics. And that may clarify the separate origins."
Monday, January 5, 2009
Competition led to Neanderthal extinction
Study shows competition, not climate change, led to Neanderthal extinction
Press release from PLoS ONE
In a recently conducted study, a multidisciplinary French-American research team with expertise in archaeology, past climates, and ecology reported that Neanderthal extinction was principally a result of competition with Cro-Magnon populations, rather than the consequences of climate change.
The study, reported in the online, open-access journal PLoS ONE on December 24, figures in the ongoing debate on the reasons behind the eventual disappearance of Neanderthal populations, which occupied Europe prior to the arrival of human populations like us around 40,000 years ago. Led by Dr William E. Banks, the authors, who belong to the French Centre National de la Recherche Scientifique, l'Ecole Pratique d'Hautes Etudes, and the University of Kansas, reached their conclusion by reconstructing climatic conditions during this period and analyzing the distribution of archaeological sites associated with the last Neanderthals and the first modern human populations with an approach typically used to study the impact of climate change on biodiversity.
This method uses geographic locations of archaeological sites dated by radiocarbon, in conjunction with high-resolution simulations of past climates for specific periods, and employs an algorithm to analyze relationships between the two datasets to reconstruct potential areas occupied by each human population and to determine if and how climatic conditions played a role in shaping these areas. In other words, by integrating archaeological and paleoenvironmental datasets, this predictive method can reconstruct the regions that a past population could potentially have occupied. By repeating the modeling process hundreds of times and evaluating where the errors occur, this machine-learning algorithm is able to provide robust predictions of regions that could have been occupied by specific human cultures.
This modeling approach also allows the projection of the ecological footprint of one culture onto the environmental conditions of a later climatic phase―by comparing this projected prediction to the known archaeological sites dated to this later period, it is possible to determine if the ecological niche exploited by this human population remained the same, or if it contracted or expanded during that period of time.
Comparing these reconstructed areas for Neanderthals and anatomically modern humans during each of the climatic phases concerned, and by projecting each niche onto the subsequent climatic phases, Banks and colleagues determined that Neanderthals had the possibility to maintain their range across Europe during a period of less severe climatic conditions called Greenland Interstadial 8 (GI8).
However, the archaeological record shows that this did not occur, and Neanderthal disappearance occurs at a point when we see the geographic expansion of the ecological niche occupied by modern humans during GI8. The researchers' models predict the southern limit of the modern human territory to be near the Ebro River Valley in northern Spain during the preceding cold period called Heinrich Event 4 (H4), and that this southern boundary moved to the south during the more temperate phase GI8.
The researchers conclude that the Neanderthal populations that occupied what is now southern Spain were the last to survive because they were able to avoid direct competition with modern humans since the two populations exploited distinct territories during the cold climatic conditions of H4. They also point out that during this population event contact between Neanderthals and modern humans may have permitted cultural and genetic exchanges.
Press release from PLoS ONE
In a recently conducted study, a multidisciplinary French-American research team with expertise in archaeology, past climates, and ecology reported that Neanderthal extinction was principally a result of competition with Cro-Magnon populations, rather than the consequences of climate change.
The study, reported in the online, open-access journal PLoS ONE on December 24, figures in the ongoing debate on the reasons behind the eventual disappearance of Neanderthal populations, which occupied Europe prior to the arrival of human populations like us around 40,000 years ago. Led by Dr William E. Banks, the authors, who belong to the French Centre National de la Recherche Scientifique, l'Ecole Pratique d'Hautes Etudes, and the University of Kansas, reached their conclusion by reconstructing climatic conditions during this period and analyzing the distribution of archaeological sites associated with the last Neanderthals and the first modern human populations with an approach typically used to study the impact of climate change on biodiversity.
This method uses geographic locations of archaeological sites dated by radiocarbon, in conjunction with high-resolution simulations of past climates for specific periods, and employs an algorithm to analyze relationships between the two datasets to reconstruct potential areas occupied by each human population and to determine if and how climatic conditions played a role in shaping these areas. In other words, by integrating archaeological and paleoenvironmental datasets, this predictive method can reconstruct the regions that a past population could potentially have occupied. By repeating the modeling process hundreds of times and evaluating where the errors occur, this machine-learning algorithm is able to provide robust predictions of regions that could have been occupied by specific human cultures.
This modeling approach also allows the projection of the ecological footprint of one culture onto the environmental conditions of a later climatic phase―by comparing this projected prediction to the known archaeological sites dated to this later period, it is possible to determine if the ecological niche exploited by this human population remained the same, or if it contracted or expanded during that period of time.
Comparing these reconstructed areas for Neanderthals and anatomically modern humans during each of the climatic phases concerned, and by projecting each niche onto the subsequent climatic phases, Banks and colleagues determined that Neanderthals had the possibility to maintain their range across Europe during a period of less severe climatic conditions called Greenland Interstadial 8 (GI8).
However, the archaeological record shows that this did not occur, and Neanderthal disappearance occurs at a point when we see the geographic expansion of the ecological niche occupied by modern humans during GI8. The researchers' models predict the southern limit of the modern human territory to be near the Ebro River Valley in northern Spain during the preceding cold period called Heinrich Event 4 (H4), and that this southern boundary moved to the south during the more temperate phase GI8.
The researchers conclude that the Neanderthal populations that occupied what is now southern Spain were the last to survive because they were able to avoid direct competition with modern humans since the two populations exploited distinct territories during the cold climatic conditions of H4. They also point out that during this population event contact between Neanderthals and modern humans may have permitted cultural and genetic exchanges.
Monday, December 22, 2008
Earliest evidence of cave-dwelling humans.
A research team led by Professor Michael Chazan, director of the University of Toronto's Archaeology Centre, has discovered the earliest evidence of our cave-dwelling human ancestors at the Wonderwerk Cave in South Africa.
Stone tools found at the bottom level of the cave — believed to be 2 million years old — show that human ancestors were in the cave earlier than ever thought before. Geological evidence indicates that these tools were left in the cave and not washed into the site from the outside world.
Archaeological investigations of the Wonderwerk cave — a South African National Heritage site due to its role in discovering the human and environmental history of the area — began in the 1940s and research continues to this day.
Wonderwerk Cave: Basic Information
Location: Northern Cape Province, South Africa between Danielskuil and Kuruman
How did the Cave Form: The cave formed by water action in the Dolemite rocks of the
Asbestos Hills. This rock formation is over 2 billion years old, some of the oldest rock
on earth, so we do not know when exactly the cave formed.
Basic properties of the cave; The cave runs 130 meters from front to back.
How was Wonderwerk discovered: Local farmers dug up large parts of the cave in the
1940’s to sell the sediments for fertilizer. Subsequently a series of brief archaeological
excavations began. Peter Beaumont of the McGregor Museum carried out major
excavations at the site between 1978-1993.
The Discovery
Using a combination of dating methods it has been possible to date the bottom level
reached by Peter Beaumont in the front part of the cave to 2 million years ago.
A small number of very small stone tools have been recovered from excavations in this
level.
Geological evidence indicates that these tools were deposited in the cave by human
ancestors, not washed into the site from the outside.
The combination of stone tools indicating the presence of human ancestors and the dating
of the level leads to the conclusion that human ancestors (hominids) were in the cave 2
million years ago.
This is the earliest evidence for intentional cave occupation by human ancestors.
There were a number of species of hominids in southern Africat 2 million years ago. The
most likely candidate as the manufacturer of the stone tools found at Wonderwerk is
Homo habilis.
The oldest known stone tools from sites in Ethiopia date to 2.4 million years. The
Wonderwerk Cave discoveries are those close in age to the very earliest known stone
tools and similar in date to the bottom levels at Olduvai Gorge.
How Was the Site Dated
The deposits at Wonderwerk Cave built up over time so that the deeper one excavates the
layers become older. The trick is to figure out exactly how old the levels are.
We used two methods that together provide a secure date.
For Paleomagnetic Dating Hagai Ron of the Hebrew University took small samples of
soil from the entire sequence (over fifty samples). These samples allow him to measure
changes in he earth’s magnetic field and to correlate the Wonderwerk sequence with a
global timescale for changes in the magnetic field (known as reversals).
For Cosmogenic Burial Age Ari Matmon, also from the Hebrew University, took soil
samples and carefully prepared them in the lab. He then sent these samples to an atomic
accelerator in the United States where a procedure to measure isotopes, much like the
method used in carbon dating, was carried out. Unlike carbon dating, Cosmogenic Burial
Age dating can provide very old dates.
Why was this so difficult? Most well dated early sites are in East Africa where there are
volcanic ash layers that can be dated using the Argon method. In southern Africa we
lack these ash layers so that we need to develop new methods. The first use of
Cosmogenic Burial Age dating in South Africa was at the Cradle of Humankind. Our
results show the value of this method, particularly when combined with Paleomagnetic
dating, for archaeological research both in the region and globally.
Stone tools found at the bottom level of the cave — believed to be 2 million years old — show that human ancestors were in the cave earlier than ever thought before. Geological evidence indicates that these tools were left in the cave and not washed into the site from the outside world.
Archaeological investigations of the Wonderwerk cave — a South African National Heritage site due to its role in discovering the human and environmental history of the area — began in the 1940s and research continues to this day.
Wonderwerk Cave: Basic Information
Location: Northern Cape Province, South Africa between Danielskuil and Kuruman
How did the Cave Form: The cave formed by water action in the Dolemite rocks of the
Asbestos Hills. This rock formation is over 2 billion years old, some of the oldest rock
on earth, so we do not know when exactly the cave formed.
Basic properties of the cave; The cave runs 130 meters from front to back.
How was Wonderwerk discovered: Local farmers dug up large parts of the cave in the
1940’s to sell the sediments for fertilizer. Subsequently a series of brief archaeological
excavations began. Peter Beaumont of the McGregor Museum carried out major
excavations at the site between 1978-1993.
The Discovery
Using a combination of dating methods it has been possible to date the bottom level
reached by Peter Beaumont in the front part of the cave to 2 million years ago.
A small number of very small stone tools have been recovered from excavations in this
level.
Geological evidence indicates that these tools were deposited in the cave by human
ancestors, not washed into the site from the outside.
The combination of stone tools indicating the presence of human ancestors and the dating
of the level leads to the conclusion that human ancestors (hominids) were in the cave 2
million years ago.
This is the earliest evidence for intentional cave occupation by human ancestors.
There were a number of species of hominids in southern Africat 2 million years ago. The
most likely candidate as the manufacturer of the stone tools found at Wonderwerk is
Homo habilis.
The oldest known stone tools from sites in Ethiopia date to 2.4 million years. The
Wonderwerk Cave discoveries are those close in age to the very earliest known stone
tools and similar in date to the bottom levels at Olduvai Gorge.
How Was the Site Dated
The deposits at Wonderwerk Cave built up over time so that the deeper one excavates the
layers become older. The trick is to figure out exactly how old the levels are.
We used two methods that together provide a secure date.
For Paleomagnetic Dating Hagai Ron of the Hebrew University took small samples of
soil from the entire sequence (over fifty samples). These samples allow him to measure
changes in he earth’s magnetic field and to correlate the Wonderwerk sequence with a
global timescale for changes in the magnetic field (known as reversals).
For Cosmogenic Burial Age Ari Matmon, also from the Hebrew University, took soil
samples and carefully prepared them in the lab. He then sent these samples to an atomic
accelerator in the United States where a procedure to measure isotopes, much like the
method used in carbon dating, was carried out. Unlike carbon dating, Cosmogenic Burial
Age dating can provide very old dates.
Why was this so difficult? Most well dated early sites are in East Africa where there are
volcanic ash layers that can be dated using the Argon method. In southern Africa we
lack these ash layers so that we need to develop new methods. The first use of
Cosmogenic Burial Age dating in South Africa was at the Cradle of Humankind. Our
results show the value of this method, particularly when combined with Paleomagnetic
dating, for archaeological research both in the region and globally.
Ancient African exodus mostly involved men
Modern humans left Africa over 60,000 years ago in a migration that many believe was responsible for nearly all of the human population that exist outside Africa today.
Now, researchers have revealed that men and women weren't equal partners in that exodus. By tracing variations in the X chromosome and in the non-sex chromosomes, the researchers found evidence that men probably outnumbered women in that migration. The scientists expect that their method of comparing X chromosomes with the other non-gender specific chromosomes will be a powerful tool for future historical and anthropological studies, since it can illuminate differences in female and male populations that were inaccessible to previous methods.
While the researchers cannot say for sure why more men than women participated in the dispersion from Africa—or how natural selection might also contribute to these genetic patterns—the study's lead author, Alon Keinan, notes that these findings are "in line with what anthropologists have taught us about hunter-gatherer populations, in which short distance migration is primarily by women and long distance migration primarily by men."
Now, researchers have revealed that men and women weren't equal partners in that exodus. By tracing variations in the X chromosome and in the non-sex chromosomes, the researchers found evidence that men probably outnumbered women in that migration. The scientists expect that their method of comparing X chromosomes with the other non-gender specific chromosomes will be a powerful tool for future historical and anthropological studies, since it can illuminate differences in female and male populations that were inaccessible to previous methods.
While the researchers cannot say for sure why more men than women participated in the dispersion from Africa—or how natural selection might also contribute to these genetic patterns—the study's lead author, Alon Keinan, notes that these findings are "in line with what anthropologists have taught us about hunter-gatherer populations, in which short distance migration is primarily by women and long distance migration primarily by men."
Tuesday, December 9, 2008
Late Neandertals & human contact in Iberia
Late Neandertals and modern human contact in southeastern Iberia
It is widely accepted that Upper Paleolithic early modern humans spread westward across Europe about 42,000 years ago, variably displacing and absorbing Neandertal populations in the process. However, Middle Paleolithic assemblages persisted for another 8,000 years in Iberia, presumably made by Neandertals. It has been unclear whether these late Middle Paleolithic Iberian assemblages were made by Neandertals, and what the nature of those humans might have been.
New research, published Dec. 8 in the Proceedings of the National Academy of Sciences, is now shedding some light on what were probably the last Neandertals.
The research is based on a study of human fossils found during the past decade at the Sima de la Palomas, Murcia, Spain by Michael Walker, professor at Universidad de Murcia, and colleagues, and published by Michael Walker, Erik Trinkaus, professor of Anthropology at Washington University in St. Louis, and colleagues.
The human fossils from the upper levels of the Sima de las Palomas are anatomically clearly Neandertals, and they are now securely dated to 40,000 years ago. They therefore establish the late persistence of Neandertals in this southwestern cul-de-sac of Europe. This reinforces the conclusion that the Neandertals were not merely swept away by advancing modern humans. The behavioral differences between these human groups must have been more subtle than the Middle-to-Upper Paleolithic technological contrasts might imply.
In addition, the Palomas Neandertals variably exhibit a series of modern human features rare or absent in earlier Neandertals. Either they were evolving on their own towards the modern human pattern, or more likely, they had contact with early modern humans around the Pyrenees. If the latter, it implies that the persistence of the Middle Paleolithic in Iberia was a matter of choice, and not cultural retardation.
From the Sima de las Palomas, other late Neandertal sites, and recent discoveries of the earliest modern humans across Europe, a complex picture is emerging of shifting contact between behaviorally similar, if culturally and biologically different, human populations. Researchers are coming to see them all more as people, flexibly making a living through the changing human and natural landscapes of the Late Pleistocene.
It is widely accepted that Upper Paleolithic early modern humans spread westward across Europe about 42,000 years ago, variably displacing and absorbing Neandertal populations in the process. However, Middle Paleolithic assemblages persisted for another 8,000 years in Iberia, presumably made by Neandertals. It has been unclear whether these late Middle Paleolithic Iberian assemblages were made by Neandertals, and what the nature of those humans might have been.
New research, published Dec. 8 in the Proceedings of the National Academy of Sciences, is now shedding some light on what were probably the last Neandertals.
The research is based on a study of human fossils found during the past decade at the Sima de la Palomas, Murcia, Spain by Michael Walker, professor at Universidad de Murcia, and colleagues, and published by Michael Walker, Erik Trinkaus, professor of Anthropology at Washington University in St. Louis, and colleagues.
The human fossils from the upper levels of the Sima de las Palomas are anatomically clearly Neandertals, and they are now securely dated to 40,000 years ago. They therefore establish the late persistence of Neandertals in this southwestern cul-de-sac of Europe. This reinforces the conclusion that the Neandertals were not merely swept away by advancing modern humans. The behavioral differences between these human groups must have been more subtle than the Middle-to-Upper Paleolithic technological contrasts might imply.
In addition, the Palomas Neandertals variably exhibit a series of modern human features rare or absent in earlier Neandertals. Either they were evolving on their own towards the modern human pattern, or more likely, they had contact with early modern humans around the Pyrenees. If the latter, it implies that the persistence of the Middle Paleolithic in Iberia was a matter of choice, and not cultural retardation.
From the Sima de las Palomas, other late Neandertal sites, and recent discoveries of the earliest modern humans across Europe, a complex picture is emerging of shifting contact between behaviorally similar, if culturally and biologically different, human populations. Researchers are coming to see them all more as people, flexibly making a living through the changing human and natural landscapes of the Late Pleistocene.
Friday, December 5, 2008
Ancient empires declined during dry spell
Cave's climate clues show ancient empires declined during dry spell
The decline of the Roman and Byzantine Empires in the Eastern Mediterranean more than 1,400 years ago may have been driven by unfavorable climate changes.
Based on chemical signatures in a piece of calcite from a cave near Jerusalem, a team of American and Israeli geologists pieced together a detailed record of the area's climate from roughly 200 B.C. to 1100 A.D. Their analysis, to be reported in an upcoming issue of the journal Quaternary Research, reveals increasingly dry weather from 100 A.D. to 700 A.D. that coincided with the fall of both Roman and Byzantine rule in the region.
The researchers, led by University of Wisconsin-Madison geology graduate student Ian Orland and professor John Valley, reconstructed the high-resolution climate record based on geochemical analysis of a stalagmite from Soreq Cave, located in the Stalactite Cave Nature Reserve near Jerusalem.
"It looks sort of like tree rings in cross-section. You have many concentric rings and you can analyze across these rings, but instead of looking at the ring widths, we're looking at the geochemical composition of each ring," says Orland.
Using oxygen isotope signatures and impurities — such as organic matter flushed into the cave by surface rain — trapped in the layered mineral deposits, Orland determined annual rainfall levels for the years the stalagmite was growing, from approximately 200 B.C. to 1100 A.D.
While cave formations have previously been used as climate indicators, past analyses have relied on relatively crude sampling tools, typically small dental drills, which required averaging across 10 or even 100 years at a time. The current analysis used an advanced ion microprobe in the Wisconsin Secondary-Ion Mass-Spectrometer (Wisc-SIMS) laboratory to sample spots just one-hundredth of a millimeter across. That represents about 100 times sharper detail than previous methods. With such fine resolution, the scientists were able to discriminate weather patterns from individual years and seasons.
Their detailed climate record shows that the Eastern Mediterranean became drier between 100 A.D. and 700 A.D., a time when Roman and Byzantine power in the region waned, including steep drops in precipitation around 100 A.D. and 400 A.D. "Whether this is what weakened the Byzantines or not isn't known, but it is an interesting correlation," Valley says. "These things were certainly going on at the time that those historic changes occurred."
The team is now applying the same techniques to older samples from the same cave. "One period of interest is the last glacial termination, around 19,000 years ago — the most recent period in Earth's history when the whole globe experienced a warming of 4 to 5 degrees Celsius," Orland says.
Formations from this period of rapid change may help them better understand how weather patterns respond to quickly warming temperatures.
Soreq Cave — at least 185,000 years old and still active — also offers the hope of creating a high-resolution long-term climate change record to parallel those generated from Greenland and Antarctic ice cores.
"No one knows what happened on the continents… At the poles, the climate might have been quite different," says Valley. "This is a record of what was going on in a very different part of the world."
The decline of the Roman and Byzantine Empires in the Eastern Mediterranean more than 1,400 years ago may have been driven by unfavorable climate changes.
Based on chemical signatures in a piece of calcite from a cave near Jerusalem, a team of American and Israeli geologists pieced together a detailed record of the area's climate from roughly 200 B.C. to 1100 A.D. Their analysis, to be reported in an upcoming issue of the journal Quaternary Research, reveals increasingly dry weather from 100 A.D. to 700 A.D. that coincided with the fall of both Roman and Byzantine rule in the region.
The researchers, led by University of Wisconsin-Madison geology graduate student Ian Orland and professor John Valley, reconstructed the high-resolution climate record based on geochemical analysis of a stalagmite from Soreq Cave, located in the Stalactite Cave Nature Reserve near Jerusalem.
"It looks sort of like tree rings in cross-section. You have many concentric rings and you can analyze across these rings, but instead of looking at the ring widths, we're looking at the geochemical composition of each ring," says Orland.
Using oxygen isotope signatures and impurities — such as organic matter flushed into the cave by surface rain — trapped in the layered mineral deposits, Orland determined annual rainfall levels for the years the stalagmite was growing, from approximately 200 B.C. to 1100 A.D.
While cave formations have previously been used as climate indicators, past analyses have relied on relatively crude sampling tools, typically small dental drills, which required averaging across 10 or even 100 years at a time. The current analysis used an advanced ion microprobe in the Wisconsin Secondary-Ion Mass-Spectrometer (Wisc-SIMS) laboratory to sample spots just one-hundredth of a millimeter across. That represents about 100 times sharper detail than previous methods. With such fine resolution, the scientists were able to discriminate weather patterns from individual years and seasons.
Their detailed climate record shows that the Eastern Mediterranean became drier between 100 A.D. and 700 A.D., a time when Roman and Byzantine power in the region waned, including steep drops in precipitation around 100 A.D. and 400 A.D. "Whether this is what weakened the Byzantines or not isn't known, but it is an interesting correlation," Valley says. "These things were certainly going on at the time that those historic changes occurred."
The team is now applying the same techniques to older samples from the same cave. "One period of interest is the last glacial termination, around 19,000 years ago — the most recent period in Earth's history when the whole globe experienced a warming of 4 to 5 degrees Celsius," Orland says.
Formations from this period of rapid change may help them better understand how weather patterns respond to quickly warming temperatures.
Soreq Cave — at least 185,000 years old and still active — also offers the hope of creating a high-resolution long-term climate change record to parallel those generated from Greenland and Antarctic ice cores.
"No one knows what happened on the continents… At the poles, the climate might have been quite different," says Valley. "This is a record of what was going on in a very different part of the world."
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