Sunday, 30 November 2008

The enigma of Lake Ontario's 11,000-year-old footprints.

In the fall of 1908, while building a waterworks tunnel east of Hanlan's Point in Toronto Bay, a work crew came across 100 footprints in a layer of blue clay. The prints appeared to have been left by people wearing moccasins – 11,000 years ago.
It was an astounding discovery, perhaps the first evidence of human habitation on Lake Ontario, but few recognized its significance.
"It looked like a trail ...," city inspector W. H. Cross told the Toronto Evening Telegram about what he saw that November day. "You could follow one man the whole way. Some footprints were on top of the others, partly obliterating them. There were footprints of all sizes, and a single print of a child's foot, three and a half inches..."
He went on to describe the way the clay had shot up under the imprints of the heels, how the prints appeared to be heading north, and how he had tried to lift a piece of the clay to preserve the prints, but it broke away in his hand.
The group – likely a family, judging by the different sized prints – could have been walking from a hunting camp on the shore of Lake Ontario to what is now downtown Toronto. Back then, the shoreline would have been more than a kilometre further south.
The story is told in a new book, Toronto: A Short Illustrated History of its First 12,000 Years, which, unlike most others that look at Toronto's past, begins at the very beginning, before recorded history. Tragically, the prints were not preserved. The tunnel workers were in a hurry to complete the job, and simply poured concrete over the clay.
"If they were found to be authentic, it would have been the only discovery of footprints of the first people of Ontario," says archaeologist Ron Williamson, who edited the book and wrote the chapter on pre-European contact. "It would have been amazing."
Though it seems shocking that a find of such potential importance was unceremoniously buried, a similar attitude toward the archaeological history of First Nations people prevails, he says.
"The fact that it was almost immediately destroyed ... I can't tell you how many times, even today, construction crews make the same argument when something significant is found: They have no time for this, they have to get going."
Without seeing the prints, it's difficult to evaluate their authenticity, Williamson says, though there's no reason to believe that Cross and company were exercising a hoax.
Hunters pursuing caribou, mastodon or mammoth were known to inhabit the shoreline, then a landscape of spruce forest and tundra, similar to Canada's sub Arctic.
Mammoth remains have been found in Toronto, most notably during excavation for the former Eaton's College Street department store at College and Yonge Sts., and at Christie Pits.
Archaeologists have found 11,000-year-old spear points east of Buffalo with mastodon bone that appear to have been shaped into tools.
The Toronto Daily Star, in fierce competition with the Toronto Telegram, also reported on the footprints story, but dismissed it. At the turn of the 19th century, it was wrongly believed that the clay in which the footprints were found dated to more than 100,000 years.
One expert consulted by the Daily Star said that since the shale was there long before man arrived, the source of the prints was not early hunters but more likely "a lobster-like animal."
"Now that we know it was only 11,000 years ago," says Williamson, "it's much more sensible."
Along with exploring the footprint mystery, the book also contains essays by local historians: Robert MacDonald on Toronto's natural history, Carl Benn on colonial transformations, and Christopher Andreae on the city's industrial development.
Roger Hall's concluding essay brings Toronto into the 21st century, with observations on the nature of the modern city, unrecognizable to the travellers whose footprints were revealed under Lake Ontario.
After World War II, Toronto was no longer the "introverted capital" it had been in 1939. The arrival of manufacturing and newcomers from southern Europe and Asia led to a strengthening economy and new cultural vibrancy. Still, Toronto was not a world-class city.
"Flattering, at least to some, but not true," Hall writes.
It was not as ancient as Delhi or, like Beijing, trying to invent itself in the modern world.
Nor was it a global power broker, like New York.
"What it was," Hall writes, "was something more attractive to most of the world's inhabitants: safe, prosperous, predictable, substantial, decent. In short, it was a good place to live in a country that could boast the same qualities."

Source: 30/11/08 ; credit:Leslie Scrivener.

Sunday, 16 November 2008

Pelvis reflects "intelligence" of H.erectus.

Pelvis dated to 1.2 million years ago shows our ancestors were born with bigger heads.

A recently discovered female pelvis is changing minds about the head size of an ancient human ancestor, Homo erectus, and consequently revising notions about how smart they may have been. Found in Gona, Ethiopia, not far from the site that yielded the 3.2 million year old remains of the famed Australopithecus afarensi "Lucy," the pelvis indicates that Homo erectus, which lived in Africa roughly 2 million years ago, had a larger birth canal than originally suspected and could have given birth to babies with bigger brains.
Before the female pelvis was found, evidence from the pelvis of a juvenile male led researchers to project that the cranial circumference and capacity of newborn Homo erectus babies was 30 percent smaller than more recent projections based on the newly discovered pelvis.
Sileshi Semaw, a paleoanthropologist at the Stone Age Institute and Indiana University-Bloomington, and his colleagues assert that the head of a baby born from this Homo erectus could have been 318 millimeters in circumference. This is at the lower end of the spectrum of modern day human beings whose cranial circumferences at birth typically range from 320-370 millimeters. Semaw and colleagues present their findings in the Nov. 14 issue of Science. The research is funded in part by the National Science Foundation.

Zina Deretsky, NSF

Source :Eurekalert 15/11/08

Friday, 14 November 2008

Prehistoric pelvis offers clues to human development

A reconstruction of the 1.2 million-year-old pelvis discovered in 2001 in the Gona Study Area at Afar, Ethiopia, that has led researchers to speculate early man was better equipped than first thought to produce larger-brained babies. The actual fossils remain in Ethiopia.

Credit: Scott W. Simpson, Case Western Reserve University

Discovery of the most intact female pelvis of Homo erectus may cause scientists to reevaluate how early humans evolved to successfully birth larger-brained babies. "This is the most complete female Homo erectus pelvis ever found from this time period," said Indiana University Bloomington paleoanthropologist Sileshi Semaw. "This discovery gives us more accurate information about the Homo erectus female pelvic inlet and therefore the size of their newborns."
A reconstruction of the 1.2 million-year-old pelvis discovered in 2001 in the Gona Study Area at Afar, Ethiopia, that has led researchers to speculate early man was better equipped than first thought to produce larger-brained babies. The actual fossils remain in Ethiopia.
The discovery will be published in Science this week (Nov. 14) by Semaw, leader of the Gona Project in Ethiopia, where the fossil pelvis was discovered with a group of six other scientists that includes IU Department of Geosciences graduate student Melanie Everett.
Reconstructing pelvis bone fragments from the 1.2 million-year-old adult female, Semaw and his co-workers determined the early ancestor's birth canal was more than 30 percent larger than earlier estimates based on a 1.5-million-year-old juvenile male pelvis found in Kenya. The new female fragments were discovered in the Gona Study Area in Afar, Ethiopia, in 2001 and excavation was completed in 2003.
Scientists also were intrigued by other unique attributes of the specimen, such as its shorter stature and broader body shape more likely seen in hominids adapted to temperate climates, rather than the tall and narrow body believed to have been efficient for endurance running.
Early humans became taller and narrower over time, scientists believe, partly due to long distance running and to help them maintain a constant body temperature. One consequence, however, is that a narrower pelvis would have been less accommodating to producing larger-brained offspring.
But rather than a tall, narrow hominid with the expected slight pelvic region, Semaw and the Gona researchers found evidence of a hominid ready to produce offspring with a much larger brain size.
"The female Homo erectus pelvic anatomy is basically unknown," Semaw said. "And as far as the fossil pelvis of ancestral hominids goes, all we've had is Lucy (dated at 3.2 million years and also found in Ethiopia), and she is very much farther back in time from modern humans."
Scientists studying early man predominantly find fragments of craniums and dental remains, while fossil bones from the neck down are rarely discovered. Even more difficult to verify are Homo erectus fossil bones that can be identified as those belonging to a female.
Scientists had thought early adult Homo erectus females, because of the assumed small birth canal, would produce offspring with only a limited neonatal brain size. These young would have then experienced rapid brain growth while still developmentally immature, leading researchers to envision a scenario of maternal involvement and child-rearing on par with that of modern humans. But those theories had been based upon extrapolations from the existing male skeleton from Kenya.
"This find will give us far more accurate information," Semaw said. Semaw is also a research scientist at the Stone Age Institute, a research center near Bloomington dedicated to the study of early human evolution and culture. It is affiliated with Indiana University's CRAFT, the Center for Research into the Anthropological Foundations of Technology.
Gona has turned out to be a productive dig site for Semaw. In 1997 Semaw and colleagues reported the oldest known stone tools used by ancestral humans. Then in 2004 he coauthored a paper summarizing Gona's geological properties and the site's cornucopia of hominid fossils spanning several million years. At the time, Science gave the article an "Editor's Choice" recognition. In 2005 he and colleagues published an article in Nature announcing the discovery of Ardipithecus ramidus, one of the earliest ancestral hominids, dating between 4.3 and 4.5 million years ago.
Source: Eurekalert 14th Nov 2008

Thursday, 6 November 2008

Skeleton of 12,000-year-old shaman discovered buried with leopard, 50 tortoises and human foot

Credit :Naftali Hilger.

The skeleton of a 12,000 year-old Natufian Shaman has been discovered in northern Israel by archaeologists at the Hebrew University of Jerusalem. The burial is described as being accompanied by "exceptional" grave offerings - including 50 complete tortoise shells, the pelvis of a leopard and a human foot. The shaman burial is thought to be one of the earliest known from the archaeological record and the only shaman grave in the whole region.
Dr. Leore Grosman of the Institute of Archaeology at the Hebrew University, who is heading the excavation at the Natufian site of Hilazon Tachtit in the western Galilee, says that the elaborate and invested interment rituals and method used to construct and seal the grave suggest that this woman had a very high standing within the community. Details of the discovery were published in the PNAS journal on November 3, 2008.

What was found in the shaman's grave?

The grave contained body parts of several animals that rarely occur in Natufian assemblages. These include fifty tortoises, the near-compete pelvis of a leopard, the wing tip of a golden eagle, tail of a cow, two marten skulls and the forearm of a wild boar which was directly aligned with the woman's left humerus.
A human foot belonging to an adult individual who was substantially larger than the interred woman was also found in the grave.
Dr. Grosman believes this burial is consistent with expectations for a shaman's grave. Burials of shamans often reflect their role in life (i.e., remains of particular animals and contents of healing kits). It seems that the woman was perceived as being in close relationship with these animal spirits.

Method of burial

The body was buried in an unusual position. It was laid on its side with the spinal column, pelvis and right femur resting against the curved southern wall of the oval-shaped grave. The legs were spread apart and folded inward at the knees.
According to Dr. Grosman, ten large stones were placed directly on the head, pelvis and arms of the buried individual at the time of burial. Following decomposition of the body, the weight of the stones caused disarticulation of some parts of the skeleton, including the separation of the pelvis from the vertebral column.
Speculating why the body was held in place in such a way and covered with rocks, Dr. Grosman suggests it could have been to protect the body from being eaten by wild animals or because the community was trying to keep the shaman and her spirit inside the grave.
Analysis of the bones show that the shaman was 45 years old, petite and had an unnatural, asymmetrical appearance due to a spinal disability that would have affected the woman's gait, causing her to limp or drag her foot.

Fifty tortoises

Most remarkably, the woman was buried with 50 complete tortoise shells. The inside of the tortoises were likely eaten as part of a feast surrounding the interment of the deceased. High representation of limb bones indicates that most tortoise remains were thrown into the grave along with the shells after consumption.
The recovery of the limb bones also indicates that entire tortoises, not only their shells, were transported to the cave for the burial. The collection of 50 living tortoises at the time of burial would have required a significant investment, as these are solitary animals. Alternatively, these animals could have been collected and confined by humans for a period preceding the event.
Shaman graves in archaeology
According to Dr. Grosman, the burial of the woman is unlike any burial found in the Natufian or the preceding Paleolithic periods. "Clearly a great amount of time and energy was invested in the preparation, arrangement, and sealing of the grave." This was coupled with the special treatment of the buried body.
Shamans are universally recorded cross-culturally in hunter-gatherer groups and small-scale agricultural societies. Nevertheless, they have rarely been documented in the archaeological record and none have been reported from the Paleolithic of Southwest Asia.
The Natufians existed in the Mediterranean region of the Levant 15,000 to 11,500 years ago. Dr. Grosman suggests this grave could point to ideological shifts that took place due to the transition to agriculture in the region at that time.

Natufian grave site

Hilazon Tachtit is a small cave site next to Carmiel that functioned first and foremost as a Natufian burial ground for at least 28 individuals representing an array of ages.
The collective graves found at the site likely served as primary burial areas that were later re-opened to remove skulls and long bones for secondary burial – a practice common to the Natufian and the following Neolithic cultures.
Only three partially complete primary burials were recovered at Hilazon Tachtit. One was a skeleton of a young adult (sex unknown) reposed in a flexed position on its right side with both hands under his face. The scattered bones of a newborn were found in the area of the missing pelvis and it appears that the newborn and the young adult, possibly the mother, were buried together.

Source:Eurekalert 5/11/08