posted
Nick A. Drakea,1, Roger M. Blenchb, Simon J. Armitagec, Charlie S. Bristowd, and Kevin H. Whitee
a Department of Geography, King’s College London, Strand, London WC2R 2LS, United Kingdom; b Kay Williamson Educational Foundation, 8 Guest Road, Cambridge CB1 2AL, United Kingdom; c Department of Geography, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom; dSchool of Earth Sciences, Birkbeck College, University of London, Malet Street, London WC1E 7HX, United Kingdom; and eDepartment of Geography, University of Reading, Whiteknights, Reading RG6 6AB, United Kingdom
Edited by Ofer Bar-Yosef, Harvard University, Cambridge, MA, and approved November 22, 2010 (received for review August 23, 2010)
Ancient watercourses and biogeography of the Sahara explain the peopling of the desert
Evidence increasingly suggests that sub-Saharan Africa is at the center of human evolution and understanding routes of dispersal “out of Africa” is thus becoming increasingly important. The Sahara Desert is considered by many to be an obstacle to these dispersals and a Nile corridor route has been proposed to cross it. Here we provide evidence that the Sahara was not an effective barrier and indicate how both animals and humans populated it during past humid phases. Analysis of the zoogeography of the Sahara shows that more animals crossed via this route than used the Nile corridor. Furthermore, many of these species are aquatic. This dis- persal was possible because during the Holocene humid period the region contained a series of linked lakes, rivers, and inland deltas comprising a large interlinked waterway, channeling water and an- imals into and across the Sahara, thus facilitating these dispersals. This system was last active in the early Holocene when many spe- cies appear to have occupied the entire Sahara. However, species that require deep water did not reach northern regions because of weak hydrological connections. Human dispersals were influenced by this distribution; Nilo-Saharan speakers hunting aquatic fauna with barbed bone points occupied the southern Sahara, while peo- ple hunting Savannah fauna with the bow and arrow spread south- ward. The dating of lacustrine sediments show that the “green Sahara” also existed during the last interglacial (∼125 ka) and pro- vided green corridors that could have formed dispersal routes at a likely time for the migration of modern humans out of Africa.
Göbekli Tepe - 11,500 B.C. Which is a hilltop sanctuary built on the highest point of an elongated mountain ridge about 15km northeast of the town of Şanlıurfa (Urfa) in southeast Turkey.
German Archaeologist Klaus Schmidt discovered: Gobeki Tepe.
This is actually what the author mentioned.
..."and would have attracted hunter-gatherers from Africa and the Levant."...
Posts: 22234 | From: האם אינכם כילדי הכרית אלי בני ישראל | Registered: Nov 2010
| IP: Logged |
posted
Ethiopian lake sediments reveal history of African droughts
A new survey of Lake Tana in Ethiopia – the source of the Blue Nile – suggests that drought may have contributed to the demise of the Egyptian Old Kingdom, around 4200 years ago.
A team led by the University of Aberystwyth used seismic surveys and sediment cores to work out how the lake's water levels has varied over the past 17,000 years and linked this to evidence for global climate change.
Understanding how and why rainfall patterns change is particularly important for sub-Saharan Africa, where prolonged droughts have such serious social and economic consequences.
The climate here is dominated by the African-Asian monsoon and the movements of the Intertropical Convergence Zone (ITCZ). This is an area of erratic weather patterns, where winds from the northern and southern hemispheres meet close to the equator: sailors know it as the Doldrums.
Seasonal movements of the ITCZ can affect the strength of the monsoon. A strong monsoon leads to higher lake levels, and this can be traced in ancient lake sediments. Lake Tana is particularly good for this kind of research because it's close to the northern limit of the ITCZ so even slight a southward movement of the ITCZ is reflected in the lake's geological history.
Fleshing out the detail of the region's rainfall history and linking it to past climate change can improve predictions of future rainfall. The detail enables scientists to check the ability of their climate models to accurately 'predict' past climate change; this fine tuning means they can be more confident of the models' accuracy when predicting future events.
There was already strong evidence for an abrupt drought in Africa around 16,500 years ago, linked to changes in the Earth's climate. The researchers wanted to understand the region's subsequent climate history, including finding any evidence for a dry period around 4200 years ago, when the Egyptian Old Kingdom declined.
"We were looking for evidence for long-term drought events to provide a historical context to data modellers," says Dr. Michael Marshall from Aberystwyth University, a lead author of the research paper published in Global and Planetary Change. "We wanted to find out when and how quickly drought has come about in the past."
The researchers used seismic (sound) survey and cores taken through the bottom of the lake, to get a picture of the stratigraphy or layers of sediment that have been carried into the lake by 17,000 years of rainfall.
They then used chemical and magnetic analysis to determine the conditions under which the sediments were deposited, giving them a picture of periods of relatively dry or wet weather. By carbon dating the layers the researchers then tied these wet/dry phases to existing evidence for climate change events – like movements in the ITCZ.
This let them align periods of sub-Saharan drought to periods of global climate change.
The Blue Nile is the main tributary of Egypt's Nile river and it delivers most of the sediment to the Nile's floodplain. These fertile soils were the bedrock of ancient Egyptian civilisation, so long-term changes in the flow of the Nile would have had a profound effect on Egyptian society.
"Finding a distinct dry period around the time of decline of the Old Kingdom is complicated by the fact that the climate was becoming drier overall during that time anyway," explains Marshall.
Nevertheless, the researchers' analysis of the sediments did reveal a distinct dry episode around 4200 years ago. This would have lowered water levels in Lake Tana and reduced the flow of the Nile, interrupting the regular supply of fertile sediment to the Nile delta. Archaeological evidence shows that the Old Kingdom was already beginning to wane; reduced Nile flow could have contributed to its demise.
This story is republished courtesy of Planet Earth online, a free, companion website to the award-winning magazine Planet Earth published and funded by the Natural Environment Research Council (NERC).
More information: Late Pleistocene and Holocene drought events at Lake Tana, the source of the Blue Nile. Michael H
Marshall, et al. doi: 10.1016/j.gloplacha.2011.06.004
Posts: 22234 | From: האם אינכם כילדי הכרית אלי בני ישראל | Registered: Nov 2010
| IP: Logged |
posted
Late Pleistocene and Holocene drought events at Lake Tana, the source of the Blue Nile
Michael H. Marshall et al.
Abstract Magnetic and geochemical core data spanning the last 17,000 years are correlated with new seismic stratigraphy from Lake Tana, Ethiopia, to infer past lake-level change and hence effective precipitation. The data confirm that low lake-level coincides with Heinrich Event 1 (H1) in the North Atlantic, as previously shown from diatom and pollen evidence (Lamb et al., 2007). The lake deepened at 15.3 cal kyr BP and abruptly returned to freshwater conditions, when the lake overflowed into the Blue Nile. Low runoff and lake levels and therefore rainfall are inferred between 13.0 and 12.5 cal kyr BP and may represent southerly suppression of the ITCZ and the associated monsoon front at the time of the Younger Dryas. Two drought episodes occurred at 8.4 and 7.5 cal kyr BP, and are also interpreted as a southward shift in the monsoon front. The first of these events appears to have preceded and been more significant than the 8.2 cal kyr BP. Precipitation declined after 6.8 cal kyr BP, although we do not see an abrupt end to the African Humid Period. This period culminated in a dry episode at ~ 4.2 cal kyr BP, supporting the view that reduced Nile flow was a contributing factor to the demise of the Egyptian Old Kingdom.
Highlights ► 17,000 years of climate change at the source of the Blue Nile, Lake Tana, Ethiopia. ► Southerly suppression of the ITCZ and monsoon front at the time of the Younger Dryas. ► Drought at 8.4 cal kyr BP preceded and was more significant than the “8.2 event”. ► No abrupt end to the so-called African Humid Period. ► Drought at Nile source a factor in the demise of the Egyptian Old Kingdom.
posted
LOL! The funny part is that these studies disprove the nonsense that is man made climate change.
Posts: 8893 | Registered: May 2005
| IP: Logged |
From Hunters to Farmers. Edited by J. Desmond Clark and Steven A. Brandt. Berkeley, Los Angeles and London: University of California Press, 1984. Pp. xi + 433. £44. Roland Olivera1
Posts: 22234 | From: האם אינכם כילדי הכרית אלי בני ישראל | Registered: Nov 2010
| IP: Logged |
posted
New Evidence Puts Man In North America 50,000 Years Ago
ScienceDaily (Nov. 18, 2004)
Dr. Al Goodyear examining artifacts in the terrace. (Photo courtesy of University of South Carolina)
ScienceDaily (Nov. 18, 2004) — Radiocarbon tests of carbonized plant remains where artifacts were unearthed last May along the Savannah River in Allendale County by University of South Carolina archaeologist Dr. Albert Goodyear indicate that the sediments containing these artifacts are at least 50,000 years old, meaning that humans inhabited North American long before the last ice age.
The findings are significant because they suggest that humans inhabited North America well before the last ice age more than 20,000 years ago, a potentially explosive revelation in American archaeology.
Goodyear, who has garnered international attention for his discoveries of tools that pre-date what is believed to be humans' arrival in North America, announced the test results, which were done by the University of California at Irvine Laboratory, Wednesday (Nov .17).
"The dates could actually be older," Goodyear says. "Fifty-thousand should be a minimum age since there may be little detectable activity left."
The dawn of modern homo sapiens occurred in Africa between 60,000 and 80,000 years ago. Evidence of modern man's migration out of the African continent has been documented in Australia and Central Asia at 50,000 years and in Europe at 40,000 years. The fact that humans could have been in North America at or near the same time is expected to spark debate among archaeologists worldwide, raising new questions on the origin and migration of the human species.
"Topper is the oldest radiocarbon dated site in North America," Goodyear says. "However, other early sites in Brazil and Chile, as well as a site in Oklahoma also suggest that humans were in the Western Hemisphere as early as 30,000 years ago to perhaps 60,000."
In 1998, Goodyear, nationally known for his research on the ice age PaleoIndian cultures dug below the 13,000-year Clovis level at the Topper site and found unusual stone tools up to a meter deeper. The Topper excavation site is on the bank of the Savannah River on property owned by Clariant Corp., a chemical corporation headquartered near Basel, Switzerland. He recovered numerous stone tool artifacts in soils that were later dated by an outside team of geologists to be 16,000 years old.
For five years, Goodyear continued to add artifacts and evidence that a pre-Clovis people existed, slowly eroding the long-held theory by archaeologists that man arrived in North America around 13,000 years ago.
Last May, Goodyear dug even deeper to see whether man's existence extended further back in time. Using a backhoe and hand excavations, Goodyear's team dug through the Pleistocene terrace soil, some 4 meters below the ground surface. Goodyear found a number of artifacts similar to the pre-Clovis forms he has excavated in recent years.
Then on the last day of the last week of digging, Goodyear's team uncovered a black stain in the soil where artifacts lay, providing him the charcoal needed for radiocarbon dating. Dr. Tom Stafford of Stafford Laboratories in Boulder, Colo., came to Topper and collected charcoal samples for dating.
"Three radiocarbon dates were obtained from deep in the terrace at Topper with two dates of 50,300 and 51,700 on burnt plant remains. One modern date related to an intrusion," Stafford says. "The two 50,000 dates indicate that they are at least 50,300 years. The absolute age is not known."
The revelation of an even older date for Topper is expected to heighten speculation about when man got to the Western Hemisphere and add to the debate over other pre-Clovis sites in the Eastern United States such as Meadowcroft Rockshelter, Pa., and Cactus Hill, Va.
In October 2005, archaeologists will meet in Columbia for a conference on Clovis and the study of earliest Americans. The conference will include a day trip to Topper, which is sure to dominate discussions and presentations at the international gathering. USC's Topper: A Timeline
May, 1998 — Dr. Al Goodyear and his team dig up to a meter below the Clovis level and encounter unusual stone tools up to two meters below surface.
May 1999 — Team of outside geologists led by Mike Waters, a researcher at Texas A&M, visit Topper site and propose a thorough geological study of locality.
May 2000 — Geology study done by consultants; ice age soil confirmed for pre-Clovis artifacts.
May 2001 — Geologists revisit Topper and obtain ancient plant remains deep down in the Pleistocene terrace. OSL (optically stimulated luminescence) dates on soils above ice age strata show pre-Clovis is at least older than 14,000.
May 2002 — Geologists find new profile showing ancient soil lying between Clovis and pre-Clovis, confirming the age of ice age soils between 16,000 - 20,000 years.
May 2003 — Archaeologists continue to excavate pre-Clovis artifacts above the terrace, as well as new, significant Clovis finds.
May 2004 — Using backhoe and hand excavations, Goodyear and his team dig deeper, down into the Pleistocene terrace, some 4 meters below the ground surface. Artifacts, similar to pre-Clovis forms excavated in previous years, recovered deep in the terrace. A black stain in the soil provides charcoal for radio carbon dating.
November 2004 — Radiocarbon dating report indicates that artifacts excavated from Pleistocene terrace in May were recovered from soil that dates some 50,000 years. The dates imply an even earlier arrival for humans in this hemisphere than previously believed, well before the last ice age. DR. ALBERT C. GOODYEAR III
University of South Carolina archaeologist Albert C. Goodyear joined the South Carolina Institute of Archaeology and Anthropology in1974 and has been associated with the Research Division since 1976. He is also the founder and director of the Allendale PaleoIndian Expedition, a program that involves members of the public in helping to excavate PaleoAmerican sites in the central Savannah River Valley of South Carolina.
Goodyear earned his bachelor's degree in anthropology from the University of South Florida (1968), his master's degree in anthropology from the University of Arkansas and his doctorate in anthropology from Arizona State University (1976). He is a member of the Society for American Archaeology, the Southeastern Archaeological Conference, the Archaeological Society of South Carolina, and the Florida Anthropological Society. He has served twice as president of the Archaeological Society of South Carolina and is on the editorial board of The Florida Anthropologist and the North American Archaeologist.
Goodyear developed his interest in archaeology in the 1960s as a member of the F1orida Anthropological Society and through avocational experiences along Florida's central Gulf Coast. He wrote and published articles about sites and artifacts from that region for The Florida Anthropologist in the late 1960s. His master's thesis on the Brand site, a late PaleoIndian Dalton site in northeast Arkansas, was published in 1974 by the Arkansas Archeological Survey. At Arizona State University, he did field research on Desert Hohokam mountain hunting and gathering sites in the Lower Sonoran desert of Southern Arizona.
Goodyear, whose primary research interest has been America's earliest human inhabitants, has focused on the period of the Pleistocene-Holocene transition dating between 12,000 and 9,000 years ago. He has taken a geoarchaeological approach to the search for deeply buried early sites by teaming up with colleagues in geology and soil science. For the past 15 years he has studied early prehistoric sites in Allendale County, S.C., in the central Savannah River Valley. These are stone tool manufacturing sites related to the abundant chert resources that were quarried in this locality.
This work has been supported by the National Park Service, the National Geographic Society, the University of South Carolina, the Archaeological Research Trust (SCIAA), the Allendale Research Fund, the Elizabeth Stringfellow Endowment Fund, Sandoz Chemical Corp. and Clariant Corp., the present owner of the site.
Goodyear is the author of over 100 articles, reports and books and regularly presents public lectures and professional papers on his PaleoIndian discoveries in South Carolina.
posted
Phonetic Clues Hint Language Is Africa-Born
By NICHOLAS WADE, NY Times
A researcher analyzing the sounds in languages spoken around the world has detected an ancient signal that points to southern Africa as the place where modern human language originated.
The finding fits well with the evidence from fossil skulls and DNA that modern humans originated in Africa. It also implies, though does not prove, that modern language originated only once, an issue of considerable controversy among linguists.
The detection of such an ancient signal in language is surprising. Because words change so rapidly, many linguists think that languages cannot be traced very far back in time. The oldest language tree so far reconstructed, that of the Indo-European family, which includes English, goes back 9,000 years at most.
Quentin D. Atkinson, a biologist at the University of Auckland in New Zealand, has shattered this time barrier, if his claim is correct, by looking not at words but at phonemes — the consonants, vowels and tones that are the simplest elements of language. Dr. Atkinson, an expert at applying mathematical methods to linguistics, has found a simple but striking pattern in some 500 languages spoken throughout the world: A language area uses fewer phonemes the farther that early humans had to travel from Africa to reach it.
Some of the click-using languages of Africa have more than 100 phonemes, whereas Hawaiian, toward the far end of the human migration route out of Africa, has only 13. English has about 45 phonemes.
This pattern of decreasing diversity with distance, similar to the well-established decrease in genetic diversity with distance from Africa, implies that the origin of modern human language is in the region of southwestern Africa, Dr. Atkinson says in an article published on Thursday in the journal Science.
Language is at least 50,000 years old, the date that modern humans dispersed from Africa, and some experts say it is at least 100,000 years old. Dr. Atkinson, if his work is correct, is picking up a distant echo from this far back in time.
Linguists tend to dismiss any claims to have found traces of language older than 10,000 years, “but this paper comes closest to convincing me that this type of research is possible,” said Martin Haspelmath, a linguist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Dr. Atkinson is one of several biologists who have started applying to historical linguistics the sophisticated statistical methods developed for constructing genetic trees based on DNA sequences. These efforts have been regarded with suspicion by some linguists.
In 2003 Dr. Atkinson and Russell Gray, another biologist at the University of Auckland, reconstructed the tree of Indo-European languages with a DNA tree-drawing method called Bayesian phylogeny. The tree indicated that Indo-European was much older than historical linguists had estimated and hence favored the theory that the language family had diversified with the spread of agriculture some 10,000 years ago, not with a military invasion by steppe people some 6,000 years ago, the idea favored by most historical linguists.
“We’re uneasy about mathematical modeling that we don’t understand juxtaposed to philological modeling that we do understand,” Brian D. Joseph, a linguist at Ohio State University, said about the Indo-European tree. But he thinks that linguists may be more willing to accept Dr. Atkinson’s new article because it does not conflict with any established area of linguistic scholarship.
“I think we ought to take this seriously, although there are some who will dismiss it out of hand,” Dr. Joseph said.
Another linguist, Donald A. Ringe of the University of Pennsylvania, said, “It’s too early to tell if Atkinson’s idea is correct, but if so, it’s one of the most interesting articles in historical linguistics that I’ve seen in a decade.”
Dr. Atkinson’s finding fits with other evidence about the origins of language. The Bushmen of the Kalahari Desert belong to one of the earliest branches of the genetic tree based on human mitochondrial DNA. Their languages belong to a family known as Khoisan and include many click sounds, which seem to be a very ancient feature of language. And they live in southern Africa, which Dr. Atkinson’s calculations point to as the origin of language. But whether Khoisan is closest to some ancestral form of language “is not something my method can speak to,” Dr. Atkinson said.
His study was prompted by a recent finding that the number of phonemes in a language increases with the number of people who speak it. This gave him the idea that phoneme diversity would increase as a population grew, but would fall again when a small group split off and migrated away from the parent group.
Such a continual budding process, which is the way the first modern humans expanded around the world, is known to produce what biologists call a serial founder effect. Each time a smaller group moves away, there is a reduction in its genetic diversity. The reduction in phonemic diversity over increasing distances from Africa, as seen by Dr. Atkinson, parallels the reduction in genetic diversity already recorded by biologists.
For either kind of reduction in diversity to occur, the population budding process must be rapid, or diversity will build up again. This implies that the human expansion out of Africa was very rapid at each stage. The acquisition of modern language, or the technology it made possible, may have prompted the expansion, Dr. Atkinson said.
“What’s so remarkable about this work is that it shows language doesn’t change all that fast — it retains a signal of its ancestry over tens of thousands of years,” said Mark Pagel, a biologist at the University of Reading in England who advised Dr. Atkinson.
Dr. Pagel sees language as central to human expansion across the globe.
“Language was our secret weapon, and as soon we got language we became a really dangerous species,” he said.
In the wake of modern human expansion, archaic human species like the Neanderthals were wiped out and large species of game, fossil evidence shows, fell into extinction on every continent shortly after the arrival of modern humans.
-------------------- Note: I am not an "Egyptologist" as claimed by some still bitter, defeated, trolls creating fake profiles and posts elsewhere. Hapless losers, you still fail. My output of hard data debunking racist nonsense has actually INCREASED since you began.. Posts: 5905 | From: The Hammer | Registered: Aug 2008
| IP: Logged |
Topic Closed
Printer-friendly view of this topic