1 June 2011 Last updated at 18:01

Ancient cave women 'left childhood homes'

By Neil Bowdler Science reporter, BBC News

"Mrs Ples" is the most famous example of A. africanus from the Sterkfontein cave site

Continue reading the main story

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Analysis of early human-like populations in southern Africa suggests females left their childhood homes, while males stayed at home.

An international team examined tooth samples for metallic traces which can be linked to the geological areas in which individuals grew up.

The conclusion was that while most the males lived and died around the same river valley, the females moved on.

Similar patterns have been observed in chimpanzees, bonobos and modern humans.

Details of the study are published in a letter in Nature.

Isotopic test

The researchers looked at the Sterkfontein and Swartkrans cave sites, north-west of the South African city of Johannesburg.

The sites contain specimens of two distinct early "hominin" species, Australopithecus africanus, a possible direct ancestor of modern humans who lived around 2-3 million years ago, and Paranthropus robustus, who lived some 1.2-2 million years ago, but who is not believed to be our direct ancestor.

They took teeth from eight A.africanus and 11 P.robustus individuals from the cave sites, and removed tiny enamel fragments by laser, to minimise damage.

These fragments were then analysed to test for particular isotopes, or forms, of the metallic element strontium, which can reveal the geological region where individuals were raised.

This is because particular isotopes of strontium dominant within a geological region are digested by individuals living there and incorporated into their tooth enamel.

A third molar from Australopithecus africanus from which a sample was taken for the study

The results showed that the larger teeth, presumed to belong to males, showed most of these individuals lived and died in the region where the Sterkfontein and Swartkrans cave sites are located.

Most of the smaller teeth, presumed to be female, showed that these individuals grew up outside the region.

"What we were trying to do was to find out how these two hominins - two different species living in different time periods - were ranging around and using the landscape in the Sterkfontein valley and beyond," Professor Julia Lee-Thorp of Oxford University told BBC News.

While initial research was aimed at looking at seasonal variations in diet, the isotopic tests pointed them instead to apparent gender variations.

"What [the results] show was that the females were more likely to come from outside the dolomite valley region than the males. It wasn't too far away but it wasn't the same natal group in which they grew up.

"We don't know whether they drifted, or they went across deliberately, or they were abducted; we have no way of knowing that kind of detail, but on the whole most of the females came from somewhere else."

Professor Lee-Thorp said the patterns resemble those seen in chimpanzees, where males tend to stay within the extended family group, hunting together within a single territory, whereas females are forced to leave, possibly to avoid inter-breeding.

But that pattern differs from the one observed in gorillas, where a dominant "silverback" male usually mates with multiple females, and other males are forced to leave the group.

This does not mean, she believes, that the males within these hominin groups were necessarily taking any great role in child-rearing.

"I think that's taking the information too far, quite frankly," she said. "In chimpanzees that doesn't happen. In that case the females are leaving, but the males take little interest in nurturing the children."

Small sample

The sample size is of course very small, with specimens rare and samples for experimentation rarer. The researchers also admit that data from these two separate species living at two separate times was pooled to provide results which were statistically significant.

"We're very obviously constrained by the amount of material we have for destructive analysis," said researcher Professor Darryl de Ruiter of Texas A&M University, during a telephone conference dedicated to the Nature paper.

"In terms of comparing the two species themselves, we did analyse them separately but [the] sample size was so small within these individuals that they were not robust statistics... and we did have to combine these samples in order to get a valid statistical result."

Professor Peter Wheeler of Liverpool John Moores University said that both sample size and methodology were issues to consider.

"You've got to be cautious when drawing conclusions from a relatively small sample. You've got even greater concerns when combining data from more than one species," he said.

However, he said, "if the differences are consistent, then it's extremely interesting and worthy of further work".

He added: "Isotopic work is providing a lot of information about the movement of modern humans in the archaeological record and if people are able to get consistent results further back into prehistory, it could provide information which is potentially useful."

Prehistoric Human Brain Found Pickled in Bog

A brain in near-perfect condition is found in a skull of a person who was decapitated over 2,600 years ago.

By Jennifer Viegas
Wed Apr 6, 2011 05:30 AM ET

THE GIST

• One of the world's best preserved prehistoric human brains was recently found in a waterlogged U.K. pit.
• The brain belonged to an Iron Age man who was hanged and then decapitated, with his head falling in the pit shortly thereafter.
• Scientists believe that submersion in liquid, anoxic environments helps to preserve human brain tissue.

A human skull dated to about 2,684 years ago with an "exceptionally preserved" human brain still inside of it was recently discovered in a waterlogged U.K. pit, according to a new Journal of Archaeological Science study.

The brain is the oldest known intact human brain from Europe and Asia, according to the authors, who also believe it's one of the best-preserved ancient brains in the world.

"The early Iron Age skull belonged to a man, probably in his thirties," lead authorSonia O'Connor told Discovery News. "Cause of death is rarely possible to determine in archaeological remains, but in this case, damage to the neck vertebrae is consistent with a hanging."

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"The head was then carefully severed from the neck using a small blade, such as a knife," added O'Connor, a post-doctoral research associate at the University of Bradford. "This was used to cut through the throat and between the vertebrae and has left a cluster of fine cut marks on the bone."

The brain-containing skull was found at Heslington, Yorkshire, in the United Kingdom. O'Connor and her team suspect the site served a ceremonial function that persisted from the Bronze Age through the early Roman period. Many pits at the site were marked with single stakes. The remains of the man were without a body, but the scientists also found the headless body of a red deer that had been deposited into a channel.

Laser imaging, chemical analysis and other examinations revealed that the brain naturally preserved over the millennia. The scientists found no evidence for bacterial or fungal activity, and described the tissue as being "odorless…with a resilient, tofu-like texture."

The condition of the brain is remarkable for its age.

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"In the air, even in the chill of a hospital mortuary, brain tissue very quickly decays to liquid before muscle and other soft tissues show much evidence of decay," O'Connor said.

She and her colleagues suggest that a fortuitous series of events -- for the brain and science, not the victim -- led to the organ's preservation. Shortly after the man was killed, his head must have been placed, or fallen into, the waterlogged pit that was free of oxygen. While other soft human body parts may not preserve well under such conditions, the wet environment appears to be perfect for keeping brains "fresh," "due to the very different chemistry of brain tissue," O'Connor said.

The researchers don't think the violent way the man was killed aided his brain's preservation. While severing his head separated it from the rest of his body, including the bacteria-filled gut, the decapitation "would also have produced a gaping wound that would have been open to immediate infection from micro-organisms involved in putrefaction." The quick burial in conditions not suited for microbial activity likely prevented that from happening.

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In addition to describing this unusually well preserved brain, the journal paper provides the first in-depth study of other prehistoric human brains and soft human tissues discovered by scientists. They include the body of the 5,000-year-old Tyrolean "Ice Man," the Inca mummies of the high Andes, the tanned bog bodies from across Northern and Western Europe, good condition bodies sealed in lead coffins -- such as the St. Bees man, and crypt burials at places like Spitalfields Church, London, where bodies with surviving brain tissue were found.

Glen Doran, chair of the anthropology department at Florida State University, told Discovery News that two aspects of the new study immediately struck him as "notable."

"First," he said, "such preservation is testimony to the amazing preservation in wet sites. Truly amazing things come out of the muck."

"The second, he added, "is the absolutely stellar analysis brought to bear on this special find."

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Based on this discovery and other known prehistoric, intact human brains, he agrees that rapid burial in an aqueous environment, as well as near-continual submersion, are essential to human brain tissue preservation.

"The cranium is well designed to protect the brain in life and can, under the right circumstances, remain on duty long after the normal expectation of service," he said.

http://news.discovery.com/archaeology/preserved-brain-bog-england-110406.html

First humans in Americas: prehistoric Texans?

Central Texas creek site, more than 15,000 years old, predates Clovis society

By Jennifer Welsh, LiveScience Staff Writer
LiveScience
updated 3/24/2011 4:31:34 PM ET

Humans camped by the shores of a small creek in Texas possibly even before the Clovis society, classically regarded as the first human inhabitants of the Americas, settled in the West.

The site, located in central Texas on the bank of Buttermilk Creek, has produced almost 16,000 artifacts, including stone chips and blade-like objects, in soil dating up to 15,500 years old, more than 2,000 years before the first evidence of Clovis culture. Many of the items are flakes from cutting or sharpening of tools, but the research team also found about 50 tools, including several cutting surfaces — including spear points and knives.

"The tools that we found there indicate that they were camping along the Buttermilk Creek," study researcher Mike Waters, at Texas A&M University, told LiveScience. "This probably would have been a place where they were living and conducting daily activities."

All of the objects were small and light and seem to indicate that the group led a mobile lifestyle, moving from place to place but always returning. From the wear and tear on the artifacts, some seem to have been used for cutting soft materials, like hides, while others may have been used on harder materials, like stone.

The prehistoric humans seem to have used the site for multiple centuries, as the soil where the artifacts were found was dated to between 12,800 and 15,500 years ago. "They would leave the site and come back, and each time leave behind evidence of their activities," Waters said. "They slowly but surely built up these deposits. Dating them shows they range from 15,500 years ago, then just keep going until the Clovis material."

The researchers couldn't date the material with the gold-standard method using carbon-14, since none of the artifacts had organic components, such as plant matter. The team used a different kind of dating on the soil around the artifacts, and some researchers called it into question. Extended excavation of the site could reveal carbon-dateable objects, which would confirm the age of the site.

If the dating is correct, this group would predate the Clovis society, long thought to have colonized the Americas 13,000 years ago, and could have given rise to the Clovis society. These prehistoric human societies are generally defined by the stone tools they used, the size and shape of which changed over time. Clovis used bigger blades and tools than those found at this layer of the Buttermilk site.

The site isn't the first to predate Clovis, though Waters believes his evidence is the clearest yet.

Not everyone agrees with Waters' interpretations of the findings, though. While other researchers don't question that there were probably human populations in America before Clovis, th

Tom Dillehay, a researcher at Vanderbilt University in Tennessee who wasn't involved in the study, told LiveScience that the ecological conditions at the site, including rain-swept mud and remnants of creek flooding, may have mixed the sediment layers, meaning the Clovis sediments could have been buried on top of the artifacts described by Waters, and therefore been considered more recent. The top layers are very thin.

Gary Haynes, of the University of Nevada, Reno, praised the authors for a "potentially major find" but had many of the same concerns about the research.

"They need to excavate a bigger area of the site before they can draw these kinds of conclusions," Dillehay told LiveScience. "I don't see that the data is there to present the conclusions that they are presenting."

http://www.msnbc.msn.com/id/42255086/ns/technology_and_science-science/

How man 'lost his penile spines'

9 March 2011

By Neil Bowdler
Science reporter, BBC News

Scientists believe men once had small spines on their genitalia such as those found in chimpanzees, cats and mice.

Analysis of the genomes of humans, chimpanzees and macaques indicates that a DNA sequence thought to play a role in the production of these spines have been deleted in humans, but has been preserved in other primates.

It suggests another genetic deletion may have led to the expansion of specific regions of the human brain.

The study is in the journal Nature.

The researchers at Stanford, Georgia and Pennsylvania State universities in the US wanted to trace evolutionary changes in human DNA.

They compared the human genome with those of the chimpanzee and macaque, and came up with 510 stretches of DNA that have been conserved in our primate relatives but deleted in humans.

Nearly all these DNA regions appear to play a regulatory role in the function of nearby genes.

The researchers then focused on two deletions, linking one to penile spines and another to the growth of specific areas of the brain.

They then tested the effects of the deleted sequences in human skin and neural tissue, and found further evidence to support their claims.

"We're trying to find the molecular basis of being human," said Professor David Kingsley of Stanford University, one of the authors of the study.

"That's a really ambitious goal; but we live at this unique time where we have the complete genome sequence of ourselves and our closest relatives, so you can systematically go through and find all the ways that we differ from other organisms."

Arms race

Penile spines are barb-like structures found in many mammals. Their role remains under debate, and they may play different roles in different species.

They may increase stimulation for the male during mating. They might also play a part in inducing female ovulation in a small number of species, but there is evidence that they can cause damage to the female too.

Then there is the suggestion that they might have evolved to remove "mating plugs" - material that some male species deposit in the female genital tract to block other males' attempts to fertilise the same female.

"It's been proposed these structures can help remove the copulatory plugs left by other males; so in some mammals with multi-male mating systems, there's quite a little arms race going on for fertilisation," said Professor Kingsley.

The researchers believe the loss of these spines in humans may be related to changes in human courtship.

The loss of spines, they say, would result in less sensitivity and longer copulation, and may be associated with stronger pair-bonding in humans and greater paternal care for human offspring.

http://www.bbc.co.uk/news/science-environment-12689692

The moment Britain became an island

15 February 2011

By Megan Lane
BBC News Magazine

Ancient Britain was a peninsula until a tsunami flooded its land-links to Europe some 8,000 years ago. Did that wave help shape the national character?

The coastline and landscape of what would become modern Britain began to emerge at the end of the last Ice Age around 10,000 years ago.

What had been a cold, dry tundra on the north-western edge of Europe grew warmer and wetter as the ice caps melted. The Irish Sea, North Sea and the Channel were all dry land, albeit land slowly being submerged as sea levels rose.

But it wasn't until 6,100BC that Britain broke free of mainland Europe for good, during the Mesolithic period - the Middle Stone Age.

It is thought that landslides in Norway - the Storegga Slides - triggered one of the biggest tsunamis ever recorded on Earth when a landlocked sea in the Norwegian trench burst its banks.

The water struck the north-east of Britain with such force it travelled 25 miles (40km) inland, turning low-lying plains into what is now the North Sea, and marshlands to the south into the Channel. Britain became an island nation.

At the time it was home to a fragile and scattered population of about 5,000 hunter-gatherers, descended from the early humans who had followed migrating herds of mammoth and reindeer onto the jagged peninsula.

"The waves would have been maybe as much as 10m (33ft) high," says geologist David Smith, of Oxford University. "Anyone standing out on the mud flats at that time would have been dismembered. The speed [of the water] was just so great."

At Montrose, on the north-east coast of Scotland, Smith has uncovered signs of this long-ago natural disaster. A layer of ancient sand runs through what should be banks of continuous clay - sand washed inland by the inundation.

Relics of these pre-island times are being recovered from under the sea off the Isle of Wight, dating from when the Solent was dry land.

Grooved timbers preserved by the saltwater are thought to be the remains of 8,000-year-old log boats, and point to the site once being a sizable boat-building yard, says Garry Momber, of the Hampshire and Wight Trust for Maritime Archaeology (see video clip below).

The tsunami was a watershed in our history, says archaeologist Neil Oliver, presenter of BBC Two's A History of Ancient Britain.

"The people living in the land that would become Britain had become different. They'd been made different. And at the same time, they'd been made a wee bit special as well."

Being so closely bordered by water meant boat-building and seafaring became a way of life. Many millennia on from the tsunami, the British sailed the ocean waves to find new lands and build an empire.

Its more recent history bristles with naval heroes, sea battles and famous explorers. English, Scottish, Welsh and Irish migrants left their homelands to settle far and wide. And Elizabeth I was not only a notable monarch for being a woman, but for presiding over a famous naval victory, and English forays into New World exploration.

But the idea of England - in particular - being a maritime nation has its roots as much in spin as in reality, says Dr Nigel Rigby, of the National Maritime Museum. An early exponent was the 16th Century writer Richard Hakluyt, who promoted the settlement of North America.

Hakluyt's writings played on the growing desire to seek new territories after the loss of Calais in 1558.

"Hakluyt's Voyages spun the idea that the English had always been stirrers and searchers abroad. But it was not really an island that had started to see a future at sea."

By the time Charles I took the throne, the lure of maritime power had taken hold. "He called his great warship the Sovereign of the Seas. It was a statement of intent," says Rigby.

For hundreds of years, ships, goods and people moved to and from the British Isles. Merchant and naval ships alike were staffed by those from far and wide, some of whom settled in its ports.

But just as Britain could reach out to the world from its safe harbours, so, too, could the world reach in - and this fuelled feelings of vulnerability, says Rigby. If an invader can make it across one's watery defences, the British coastline offers an abundance of places in which to make landfall.

"The 19th Century writer Alfred Thayer Mahan made the point that if you look at the coastline of Britain, it's suited to maritime trade with good harbours. But easy access for trade means it's also vulnerable to attack from the sea.

"In times of national threat, this is a recurring fear. Hence the importance of being able to defeat enemies at sea," says Rigby.

Mahan's writings underlined the sense of Britain as an island nation, defined by its relationship with the sea. This identity was further bolstered by the likes of the novelist Erskine Childers, who wrote The Riddle of the Sands, a spy novel in the early 20th Century about a German plot to invade from across the North Sea.

"The idea of an 'island nation' is something of a cultural construct," says Rigby.

"But in Britain you are never more than 60 miles from the sea. So it's important to be able to defend the coastline, and to be able to make a living from all around that coastline too."

Many believe its island status has also shaped Britain's rather detached attitude to Europe today, which is still often referred to as "the continent". 

In the past, historian David Starkey has argued that Henry VIII's break from the Catholic Church in Rome made him the first Eurosceptic.

"In plans for the elaborate coastal defences that Henry commissioned we can see how England no longer defined itself as part of Europe, but as separate from it - a nation apart," he wrote in the Camden New Journal.

"Catholic Europe was now the threat, the launch pad for invasion. In other words Henry was the first Eurosceptic: the xenophobic, insular politics he created have helped to define English history for the past five centuries."

Find out about ancient sites, and activities relating to ancient Britain, on the BBC Hands On History website.

http://www.bbc.co.uk/news/magazine-12244964
(Submitted by Dawn Holloway)

On their own 2 feet: 3.2 million-year-old fossil foot bone supports humanlike bipedalism in Lucy's species

February 10, 2011

A fossilized foot bone recovered from Hadar, Ethiopia, shows that by 3.2 million years ago human ancestors walked bipedally with a modern human-like foot, a report that appears Feb. 11 in the journal Science, concludes. The fossil, a fourth metatarsal, or midfoot bone, indicates that a permanently arched foot was present in the species Australopithecus afarensis, according to the report authors, Carol Ward of the University of Missouri, together with William Kimbel and Donald Johanson, of Arizona State University's Institute of Human Origins.

The research helps resolve a long-standing debate between paleoanthropologists who think A. afarensis walked essentially as modern humans do and those who think this species practiced a form of locomotion intermediate between the quadrupedal tree-climbing of chimpanzees and human terrestrial bipedalism. The question of whether A. afarensis had fully developed pedal, or foot, arches has been part of this debate. The fourth metatarsal described in the Science report provides strong evidence for the arches and, the authors argue, support a modern-human style of locomotion for this species. The specimen was recovered from the Hadar locality 333, popularly known as the "First Family Site," the richest source of A. afarensis fossils in eastern Africa, with more than 250 specimens, representing at least 17 individuals, so far known.

"This fourth metatarsal is the only one known of A. afarensis and is a key piece of evidence for the early evolution of the uniquely human way of walking," says Kimbel. "The ongoing work at Hadar is producing rare parts of the skeleton that are absolutely critical for understanding how our species evolved."

Humans, uniquely among primates, have two arches in their feet, longitudinal and transverse, which are composed of the midfoot bones and supported by muscles in the sole of the foot. During bipedal locomotion, these arches perform two critical functions: leverage when the foot pushes off the ground and shock absorption when the sole of the foot meets the ground at the completion of the stride. Ape feet lack permanent arches, are more flexible than human feet and have a highly mobile large toe, important attributes for climbing and grasping in the trees. None of these apelike features are present in the foot of A. afarensis.

"Understanding that the foot arches appeared very early in our evolution shows that the unique structure of our feet is fundamental to human locomotion," observes Ward. "If we can understand what we were designed to do and how natural selection shaped the human skeleton, we can gain insight into how our skeletons work today. Arches in our feet were just as important for our ancestors as they are for us."

This species, whose best-known specimen is "Lucy," lived in eastern Africa 3.0𔃁.8 million years ago. Prior to A. afarensis, the species A. anamensis was present in Kenya and Ethiopia from 4.2 to 4.0 million years ago, but its skeleton is not well known. At 4.4 million years ago, Ethiopia's Ardipithecus ramidus is the earliest human ancestor well represented by skeletal remains. Although Ardipithecus appears to have been a part-time terrestrial biped, its foot retains many features of tree-dwelling primates, including a divergent, mobile first toe. The foot of A. afarensis, as with other parts of its skeleton, is much more like that of living humans, implying that by the time of Lucy, our ancestors no longer depended on the trees for refuge or resources.

The Hadar project is the longest running paleoanthropology field program in the Ethiopian rift valley, now spanning more than 38 years. Since 1973, the fieldwork at Hadar has produced more than 370 fossil specimens of Australopithecus afarensis between 3.4 and 3.0 million years ago – one of the largest collections of a single fossil hominin species in Africa – as well as one of the earliest known fossils of Homo and abundant Oldowan stone tools (ca. 2.3 million).

Through ASU's Institute of Human Origins, the Hadar project plays an important role in training Ethiopian scholars by offering graduate degree and postdoctoral opportunities in the U.S. Promotion of local awareness of the global scientific importance and Ethiopian cultural heritage value of the Hadar site is also a project priority. Additionally, the fundraising phase of a planned "Hadar Interpretive Center" at Eloaha town, 30 kilometers from the site, was successfully completed in January 2011.

Provided by Arizona State University (news : web)

http://www.physorg.com/news/2011-02-feet-million-year-old-fossil-foot-bone.html

Finding Would Reveal Contact between Humans and Gomphotheres in North America

Tuesday, February 1, 2011

MEXICO CITY.- Mexican Archaeologists discovered 3 Clovis projectile heads associated to remains of gomphotheres with an age of at least 12,000 years, in the northern region of the Mexican state of Sonora. The finding is relevant because these are the first evidences in North America of this extinct animal linked to the human species.

The finding opens the possibility of the coexistence of humankind with gomphotheres, animals similar to mammoths, but smaller, in this region of America, which contrasts with theories that declare that this species disappeared 30,000 years ago in this region of America and did not coexist with humans.

The discovery took place in early January 2011 in El Fin del Mundo, Sonora by researchers from the National Institute of Anthropology and History (INAH), during the third field season at the site identified as a hunting and quartering area during the Pleistocene.

This finding completes a scene in which archaeologists visualized how Clovis groups hunted this elephant ancestor. “This is an unprecedented finding in Mexico since it is the first time that projectile heads are found associated to a bone bed of this kind of proboscides.

“There is no other Clovis archaeological site where gomphotheres have been found, not even in the United States, where most important Clovis Culture findings have been registered, and these vestiges are dated between 10,600 and 11,600 years” informed archaeologist Guadalupe Sanchez, director of the Fin del Mundo Research Project.

“The discovery took place in the same archaeological context where in 2008 gomphothere bones and different lithic tools were found on the surface, among them, a quartz crystal Clovis head”.

Clovis people are also known as hunters of mammoths, one of 3 proboscide species that lived in America, being the other 2 the mastodon and the gomphothere. The last was the smallest and the earliest to appear in the Americas.

Gomphotheres have only been found associated to humans in South America, and the southernmost Clovis heads were found in Costa Rica; human evidence associated with proboscides was limited mastodons and mammoths, until now.

The INAH archaeologist Natalia Martinez, head of the field research, explained that Clovis projectile heads were discovered in the point named Localidad 1, the remainder of a swamp with deposits of the Pleistocene and Holocene eras, and were freed by scraping carefully a hard soil block.

The lithic artifacts manufactured by Clovis people to hunt great animals, were located a few centimeters under the gomphothere discovered in previous field seasons part of the research project conducted by the INAH, the University of Arizona and the National Geographic Society.

http://www.artdaily.org/index.asp?int_sec=2&int_new=44345
(Submitted by Terry W. Colvin)

Finding Would Reveal Contact between Humans and Gomphotheres in North America

Tuesday, February 1, 2011

MEXICO CITY.- Mexican Archaeologists discovered 3 Clovis projectile heads associated to remains of gomphotheres with an age of at least 12,000 years, in the northern region of the Mexican state of Sonora. The finding is relevant because these are the first evidences in North America of this extinct animal linked to the human species.

The finding opens the possibility of the coexistence of humankind with gomphotheres, animals similar to mammoths, but smaller, in this region of America, which contrasts with theories that declare that this species disappeared 30,000 years ago in this region of America and did not coexist with humans.

The discovery took place in early January 2011 in El Fin del Mundo, Sonora by researchers from the National Institute of Anthropology and History (INAH), during the third field season at the site identified as a hunting and quartering area during the Pleistocene.

This finding completes a scene in which archaeologists visualized how Clovis groups hunted this elephant ancestor. “This is an unprecedented finding in Mexico since it is the first time that projectile heads are found associated to a bone bed of this kind of proboscides.

“There is no other Clovis archaeological site where gomphotheres have been found, not even in the United States, where most important Clovis Culture findings have been registered, and these vestiges are dated between 10,600 and 11,600 years” informed archaeologist Guadalupe Sanchez, director of the Fin del Mundo Research Project.

“The discovery took place in the same archaeological context where in 2008 gomphothere bones and different lithic tools were found on the surface, among them, a quartz crystal Clovis head”.

Clovis people are also known as hunters of mammoths, one of 3 proboscide species that lived in America, being the other 2 the mastodon and the gomphothere. The last was the smallest and the earliest to appear in the Americas.

Gomphotheres have only been found associated to humans in South America, and the southernmost Clovis heads were found in Costa Rica; human evidence associated with proboscides was limited mastodons and mammoths, until now.

The INAH archaeologist Natalia Martinez, head of the field research, explained that Clovis projectile heads were discovered in the point named Localidad 1, the remainder of a swamp with deposits of the Pleistocene and Holocene eras, and were freed by scraping carefully a hard soil block.

The lithic artifacts manufactured by Clovis people to hunt great animals, were located a few centimeters under the gomphothere discovered in previous field seasons part of the research project conducted by the INAH, the University of Arizona and the National Geographic Society.

http://www.artdaily.org/index.asp?int_sec=2&int_new=44345
(Submitted by Terry W. Colvin)

Humans 'left Africa much earlier'

27 January 2011 Last updated at 19:33

By Paul Rincon Science reporter, BBC News

The tools from Jebel Faya (pictured) were made by modern humans, the researchers argue

Modern humans may have emerged from Africa up to 50,000 years earlier than previously thought, a study suggests.

Researchers have uncovered stone tools in the Arabian peninsula that they say were made by modern humans about 125,000 years ago.

The tools were unearthed at the site of Jebel Faya in the United Arab Emirates, a team reports in the journal Science.

The results are controversial: genetic data strongly points to an exodus from Africa 60,000-70,000 years ago.

Simon Armitage, from Royal Holloway, University of London, Hans-Peter Uerpmann, from the University of Tuebingen, Germany, and colleagues, uncovered 125,000-year-old stone tools at Jebel Faya which resemble those found in East Africa at roughly the same time period.

The authors of the study say the people who made the tools were newcomers in the area with origins on the other side of the Red Sea.

The researchers were able to date the tools using a light-based technique, which tells scientists when the stone artefacts were buried.

Genetics questioned

So-called anatomically modern humans are thought to have emerged somewhere in Africa some 200,000 years ago.

They later spread out, migrating to other continents where they displaced the indigenous human groups such as the Neanderthals in Europe and the Denisovans in Asia.

DNA from the cell's powerhouses - or mitochondria - can be used as a "clock" for reconstructing the timing of human migrations. This is because mitochondrial DNA (mtDNA) accumulates mutations, or changes, at a known rate.

Researchers used a dating technique that relies on when the tools were buried

Studies of mtDNA had suggested a timing for the "Out of Africa" exodus of 60-70,000 years ago.

But scientists behind the latest study argue that the people who made tools at Jebel Faya 125,000 years ago are ancestral to humans living outside Africa today.

Professor Uerpmann said the estimates of time using genetic data were "very rough".

"The domestic dog was said to be 120,000 years old, and now it is 20,000. You can imagine how variable the genetic dating is," he explained.

Commenting on the findings, Professor Chris Stringer, a palaeoanthropologist at London's Natural History Museum, said: "This archaeological work by Armitage and colleagues provides important clues that early modern humans might have dispersed from Africa across Arabia, as far as the Straits of Hormuz, by 120,000 years ago.

"This research augments the controversial idea that such populations could have migrated even further across southern Asia, despite conflicting genetic data that such movements only occurred after 60,000 years."

Multiple migrations?

The researchers say the toolmakers at Jebel Faya may have reached the Arabian Peninsula at a time when changes in the climate were transforming it from arid desert into a grassland habitat with lakes and rivers.

These human groups could later have moved on towards the Persian Gulf, trekking around the Iranian coast and on to South Asia.

Indeed, Dr Mike Petraglia at the University of Oxford has uncovered tools in India that he says could have been made by modern humans before 60,000 years ago. Some tools were sandwiched in ash from the eruption of the Toba super-volcano in Indonesia that geologists can date very accurately to 74,000 years ago.

However, other researchers suggest that the people living in India at this time could have died out and been replaced by a later wave of humans.

Anthropologists already knew of an early foray out of Africa by modern humans. Remains found at Skhul and Qafzeh in Israel date to between 119,000 and 81,000 years ago.

But the Skhul and Qafzeh people are generally thought to have died out or retreated south, perhaps because of climatic fluctuations. They subsequently disappear, and their sites are re-occupied by Neanderthals.

Professor Stringer said the fact that the tools found at Jebel Faya did not resemble those associated with modern humans at Qafzeh and Skhul hinted at "yet more complexity in the exodus of modern humans from Africa".

He posed the question: "Could there have been separate dispersals, one from East Africa into Arabia, and another from North Africa into the Levant?"

http://www.bbc.co.uk/news/science-environment-12300228

Humans 'left Africa much earlier'

27 January 2011 Last updated at 19:33

By Paul Rincon Science reporter, BBC News

The tools from Jebel Faya (pictured) were made by modern humans, the researchers argue

Modern humans may have emerged from Africa up to 50,000 years earlier than previously thought, a study suggests.

Researchers have uncovered stone tools in the Arabian peninsula that they say were made by modern humans about 125,000 years ago.

The tools were unearthed at the site of Jebel Faya in the United Arab Emirates, a team reports in the journal Science.

The results are controversial: genetic data strongly points to an exodus from Africa 60,000-70,000 years ago.

Simon Armitage, from Royal Holloway, University of London, Hans-Peter Uerpmann, from the University of Tuebingen, Germany, and colleagues, uncovered 125,000-year-old stone tools at Jebel Faya which resemble those found in East Africa at roughly the same time period.

The authors of the study say the people who made the tools were newcomers in the area with origins on the other side of the Red Sea.

The researchers were able to date the tools using a light-based technique, which tells scientists when the stone artefacts were buried.

Genetics questioned

So-called anatomically modern humans are thought to have emerged somewhere in Africa some 200,000 years ago.

They later spread out, migrating to other continents where they displaced the indigenous human groups such as the Neanderthals in Europe and the Denisovans in Asia.

DNA from the cell's powerhouses - or mitochondria - can be used as a "clock" for reconstructing the timing of human migrations. This is because mitochondrial DNA (mtDNA) accumulates mutations, or changes, at a known rate.

Researchers used a dating technique that relies on when the tools were buried

Studies of mtDNA had suggested a timing for the "Out of Africa" exodus of 60-70,000 years ago.

But scientists behind the latest study argue that the people who made tools at Jebel Faya 125,000 years ago are ancestral to humans living outside Africa today.

Professor Uerpmann said the estimates of time using genetic data were "very rough".

"The domestic dog was said to be 120,000 years old, and now it is 20,000. You can imagine how variable the genetic dating is," he explained.

Commenting on the findings, Professor Chris Stringer, a palaeoanthropologist at London's Natural History Museum, said: "This archaeological work by Armitage and colleagues provides important clues that early modern humans might have dispersed from Africa across Arabia, as far as the Straits of Hormuz, by 120,000 years ago.

"This research augments the controversial idea that such populations could have migrated even further across southern Asia, despite conflicting genetic data that such movements only occurred after 60,000 years."

Multiple migrations?

The researchers say the toolmakers at Jebel Faya may have reached the Arabian Peninsula at a time when changes in the climate were transforming it from arid desert into a grassland habitat with lakes and rivers.

These human groups could later have moved on towards the Persian Gulf, trekking around the Iranian coast and on to South Asia.

Indeed, Dr Mike Petraglia at the University of Oxford has uncovered tools in India that he says could have been made by modern humans before 60,000 years ago. Some tools were sandwiched in ash from the eruption of the Toba super-volcano in Indonesia that geologists can date very accurately to 74,000 years ago.

However, other researchers suggest that the people living in India at this time could have died out and been replaced by a later wave of humans.

Anthropologists already knew of an early foray out of Africa by modern humans. Remains found at Skhul and Qafzeh in Israel date to between 119,000 and 81,000 years ago.

But the Skhul and Qafzeh people are generally thought to have died out or retreated south, perhaps because of climatic fluctuations. They subsequently disappear, and their sites are re-occupied by Neanderthals.

Professor Stringer said the fact that the tools found at Jebel Faya did not resemble those associated with modern humans at Qafzeh and Skhul hinted at "yet more complexity in the exodus of modern humans from Africa".

He posed the question: "Could there have been separate dispersals, one from East Africa into Arabia, and another from North Africa into the Levant?"

http://www.bbc.co.uk/news/science-environment-12300228

Researchers to drill for ancient DNA in 'hobbit' tooth

Prospects of recovering ancient DNA from boosted by study on teeth.

January 5, 2011

Nature News

By Cheryl Jones


Scientists are planning an attempt to extract DNA from the "hobbit" Homo floresiensis, the 1-meter-tall extinct distant relative of modern humans that was unearthed in Indonesia, following a study that suggests problems in standard sampling methods in ancient-DNA research could have thwarted previous efforts.

This year, geneticists at the Australian Centre for Ancient DNA (ACAD) at the University of Adelaide hope to recover DNA from a roughly 18,000-year-old H. floresiensis tooth, which was excavated in 2009 from the Liang Bua site on the Indonesian island of Flores.

The premolar has been kept cold, and has been handled as little as possible to prevent contamination with modern DNA. But little, if any, of the ancient DNA is likely to have survived the heat and moisture of the tropics, and any that has may be highly fragmented.

Tony Djubiantono, director of the Indonesian National Centre for Archaeology in Jakarta, where the tooth is held, says that developments in DNA extraction techniques could overcome previous sampling problems, and have exciting potential for understanding the evolutionary history of H. floresiensis.

If the DNA can be extracted, comparing its sequence to that of other species could settle disputes over classification. For instance, Peter Brown, a paleoanthropologist at the University of New England in Armidale, Australia, who described and named the species in 2004, is rethinking his initial classification. At first he put the species in the human genus Homo, but he now suspects that the hobbit's ancestors left Africa before Homo evolved so the species could belong to a different or new genus.

Teething troubles

Five years ago, two teams, one from ACAD and one from the Max Planck Institute of Evolutionary Anthropology in Leipzig, Germany, attempted to recover DNA from another H. floresiensis tooth excavated in 2003. Both attempts failed.

Now, a team led by Christina Adler, a geneticist at ACAD, has found that standard sampling procedures could be responsible for the failure to get DNA from the hobbit and some other ancient specimens.

Adler's team--which included some researchers involved in the original H. floresiensis DNA recovery attempt--compared the impacts of various sampling techniques on DNA from the mitochondria of 40 human specimens from around the world, which had been dated up to 7,500 years old. The results have been accepted for publication in the Journal of Archaeological Science.

Most genetics research on ancient teeth has focused on the inner tooth tissue, dentine, but Adler's team found that cementum, the coating of the root, was a richer source of DNA.

Drilling is a technique commonly used to sample teeth and bone, because it minimizes damage to the precious specimen. But Adler's team found that the heat generated at standard drill speeds of more than 1,000 revolutions per minute (RPM) destroys DNA rapidly, causing yields to be up to 30 times lower than for samples pulverized in a mill. Reducing the drill speed to 100 RPM alleviated the problem.

The Max Planck team sampled dentine from the hobbit tooth in its early attempt to recover DNA, but it is unclear what drill speed was used. And although the ACAD scientists used the lower drill speed, they also concentrated on dentine. They will target cementum in their next attempt.

Small chance

Adler says that several ancient specimens that previously failed to yield DNA might now warrant re-sampling. She is surprised that ancient-DNA researchers commonly choose to drill at high speeds for samples, because dentists have long known that this harms their patients' teeth. "This is a case of a lack of communication between two specialist fields that are both working on similar things independently," she says.

Matthew Collins, a specialist in ancient-protein analysis who is based at the University of York, UK, says that Adler's team's results will "help to ensure that we minimize the destruction of molecules during sampling of precious fossils, and potentially enable us to reach even further back in time to recover sequence information."

However, he is pessimistic about the chances of winkling DNA out of H. floresiensis, saying that the molecules are probably too fragmented owing to high temperatures at the excavation site.

But the ACAD scientists think that it is worth making an attempt on their H. floresiensis tooth. They have been encouraged by their successful extraction of DNA from a 6,000-year-old pig tooth from the site in 2007.

http://www.scientificamerican.com/article.cfm?id=researchers-to-drill-for-hobbit

Researchers to drill for ancient DNA in 'hobbit' tooth

Prospects of recovering ancient DNA from boosted by study on teeth.

January 5, 2011

Nature News

By Cheryl Jones


Scientists are planning an attempt to extract DNA from the "hobbit" Homo floresiensis, the 1-meter-tall extinct distant relative of modern humans that was unearthed in Indonesia, following a study that suggests problems in standard sampling methods in ancient-DNA research could have thwarted previous efforts.

This year, geneticists at the Australian Centre for Ancient DNA (ACAD) at the University of Adelaide hope to recover DNA from a roughly 18,000-year-old H. floresiensis tooth, which was excavated in 2009 from the Liang Bua site on the Indonesian island of Flores.

The premolar has been kept cold, and has been handled as little as possible to prevent contamination with modern DNA. But little, if any, of the ancient DNA is likely to have survived the heat and moisture of the tropics, and any that has may be highly fragmented.

Tony Djubiantono, director of the Indonesian National Centre for Archaeology in Jakarta, where the tooth is held, says that developments in DNA extraction techniques could overcome previous sampling problems, and have exciting potential for understanding the evolutionary history of H. floresiensis.

If the DNA can be extracted, comparing its sequence to that of other species could settle disputes over classification. For instance, Peter Brown, a paleoanthropologist at the University of New England in Armidale, Australia, who described and named the species in 2004, is rethinking his initial classification. At first he put the species in the human genus Homo, but he now suspects that the hobbit's ancestors left Africa before Homo evolved so the species could belong to a different or new genus.

Teething troubles

Five years ago, two teams, one from ACAD and one from the Max Planck Institute of Evolutionary Anthropology in Leipzig, Germany, attempted to recover DNA from another H. floresiensis tooth excavated in 2003. Both attempts failed.

Now, a team led by Christina Adler, a geneticist at ACAD, has found that standard sampling procedures could be responsible for the failure to get DNA from the hobbit and some other ancient specimens.

Adler's team--which included some researchers involved in the original H. floresiensis DNA recovery attempt--compared the impacts of various sampling techniques on DNA from the mitochondria of 40 human specimens from around the world, which had been dated up to 7,500 years old. The results have been accepted for publication in the Journal of Archaeological Science.

Most genetics research on ancient teeth has focused on the inner tooth tissue, dentine, but Adler's team found that cementum, the coating of the root, was a richer source of DNA.

Drilling is a technique commonly used to sample teeth and bone, because it minimizes damage to the precious specimen. But Adler's team found that the heat generated at standard drill speeds of more than 1,000 revolutions per minute (RPM) destroys DNA rapidly, causing yields to be up to 30 times lower than for samples pulverized in a mill. Reducing the drill speed to 100 RPM alleviated the problem.

The Max Planck team sampled dentine from the hobbit tooth in its early attempt to recover DNA, but it is unclear what drill speed was used. And although the ACAD scientists used the lower drill speed, they also concentrated on dentine. They will target cementum in their next attempt.

Small chance

Adler says that several ancient specimens that previously failed to yield DNA might now warrant re-sampling. She is surprised that ancient-DNA researchers commonly choose to drill at high speeds for samples, because dentists have long known that this harms their patients' teeth. "This is a case of a lack of communication between two specialist fields that are both working on similar things independently," she says.

Matthew Collins, a specialist in ancient-protein analysis who is based at the University of York, UK, says that Adler's team's results will "help to ensure that we minimize the destruction of molecules during sampling of precious fossils, and potentially enable us to reach even further back in time to recover sequence information."

However, he is pessimistic about the chances of winkling DNA out of H. floresiensis, saying that the molecules are probably too fragmented owing to high temperatures at the excavation site.

But the ACAD scientists think that it is worth making an attempt on their H. floresiensis tooth. They have been encouraged by their successful extraction of DNA from a 6,000-year-old pig tooth from the site in 2007.

http://www.scientificamerican.com/article.cfm?id=researchers-to-drill-for-hobbit

Sabretooth cats threatened most ancient human ancestor

3 January 2011
By Paul Rincon Science reporter, BBC News

Humankind's oldest known ancestor probably lived in fear of several large sabretooth cats that roamed the same ancient lakeside habitat in Africa.

Palaeontologists have identified two new sabretooth species among fossils unearthed at Toros Menalla in Chad.

In 2001, a team unearthed remains of a seven million-year-old human-like creature - or hominid - known as "Toumai" at the central African site.

Its discoverers argue that Toumai is the oldest hominid known to science.

The fossilised skull of Toumai (which means "hope of life" in the local Dazaga language of Chad) was found in the Djurab desert by a team led by Michael Brunet of the University of Poitiers, France.

The position of a hole at the bottom of the skull called the foramen magnum suggests that Toumai (Sahelanthropus tchadensis) walked upright - an important signature of the human lineage.

The brainstem enters and exits the skull through this hole; in great apes, it is positioned more towards the back of the skull. But in hominids - including Toumai - it is placed more towards the front of the skull.

The ancient fossil caused a worldwide sensation when it was unveiled in the pages of Nature journal in 2002.

However, the interpretation of Toumai as a human relative is controversial. The skull was distorted and, if any other parts of the skeleton happen to exist, none has yet been published in the scientific literature. It is also older than the date when genetics says that the human and chimp lineages diverged.

Predator's playground

Nevertheless, palaeontologists have been busy studying the abundant fossil material unearthed at the site, steadily building a picture of the environment in which Sahelanthropus eked out its existence.

In Late Miocene times, this area of Chad must have had a lake, because palaeontologists have found the fossilised remains of fish, amphibians and crocodiles.

But they have also found evidence of grasslands, gallery forest and a desert.

Researchers have discovered the fossilised remains of a wide variety of carnivorous mammals at Toros Menalla. Ending up in the sharp jaws of a predator must have been an ever-present threat for primates like Toumai.

Palaentologists had already reported finding remains of a large sabretooth cat from Toros Menalla known as Machairodus kabir which weighed in at 350-490kg.

Writing in the journal Comptes Rendus Palevol, Louis de Bonis from Poitiers University and colleagues add two new sabretooth species to the growing list of carnivores that stalked this region of central Africa in late Miocene times.

The big cat remains were unearthed during recent field expeditions and have been identified as new species belonging to the genus Lokotunjailurus and the genus Megantereon.

Forest refuge

Patrick Vignaud, director of Poitier University's Institute of Palaeo-primatology and Human Palaeontology, told BBC News the cats were about the same size as modern lions.

"With our present data, we don't know what precisely the interactions were between a primate and a big carnivore. But probably these interactions were not so friendly," said Professor Vignaud.

He told BBC News: "Sabretooths hunted all mammals; bovids, equids... and primates. The interactions were also more 'psychological', exercising a stress on potential prey. We can't prove it but it's probably important because in that case, primates had to live near closed environments like gallery forest."

While ancient primates like Sahelanthropus tchadensis gave sabretooth cats a wide berth, they may also have depended on these big carnivores - and others - for their survival.

Sabretooths would have hunted large herbivorous mammals, and probably left enough meat on their kills for scavengers like the jackal-sized Hyaenictherium and perhaps even primates like Sahelanthropus.

Some researchers have proposed that Toumai is more closely related to chimpanzees or gorillas. Even if this were the case, the discovery would be of great significance, as virtually no fossil ancestors of these great apes are known from Africa.

http://www.bbc.co.uk/news/science-environment-11979934

Sabretooth cats threatened most ancient human ancestor

3 January 2011
By Paul Rincon Science reporter, BBC News

Humankind's oldest known ancestor probably lived in fear of several large sabretooth cats that roamed the same ancient lakeside habitat in Africa.

Palaeontologists have identified two new sabretooth species among fossils unearthed at Toros Menalla in Chad.

In 2001, a team unearthed remains of a seven million-year-old human-like creature - or hominid - known as "Toumai" at the central African site.

Its discoverers argue that Toumai is the oldest hominid known to science.

The fossilised skull of Toumai (which means "hope of life" in the local Dazaga language of Chad) was found in the Djurab desert by a team led by Michael Brunet of the University of Poitiers, France.

The position of a hole at the bottom of the skull called the foramen magnum suggests that Toumai (Sahelanthropus tchadensis) walked upright - an important signature of the human lineage.

The brainstem enters and exits the skull through this hole; in great apes, it is positioned more towards the back of the skull. But in hominids - including Toumai - it is placed more towards the front of the skull.

The ancient fossil caused a worldwide sensation when it was unveiled in the pages of Nature journal in 2002.

However, the interpretation of Toumai as a human relative is controversial. The skull was distorted and, if any other parts of the skeleton happen to exist, none has yet been published in the scientific literature. It is also older than the date when genetics says that the human and chimp lineages diverged.

Predator's playground

Nevertheless, palaeontologists have been busy studying the abundant fossil material unearthed at the site, steadily building a picture of the environment in which Sahelanthropus eked out its existence.

In Late Miocene times, this area of Chad must have had a lake, because palaeontologists have found the fossilised remains of fish, amphibians and crocodiles.

But they have also found evidence of grasslands, gallery forest and a desert.

Researchers have discovered the fossilised remains of a wide variety of carnivorous mammals at Toros Menalla. Ending up in the sharp jaws of a predator must have been an ever-present threat for primates like Toumai.

Palaentologists had already reported finding remains of a large sabretooth cat from Toros Menalla known as Machairodus kabir which weighed in at 350-490kg.

Writing in the journal Comptes Rendus Palevol, Louis de Bonis from Poitiers University and colleagues add two new sabretooth species to the growing list of carnivores that stalked this region of central Africa in late Miocene times.

The big cat remains were unearthed during recent field expeditions and have been identified as new species belonging to the genus Lokotunjailurus and the genus Megantereon.

Forest refuge

Patrick Vignaud, director of Poitier University's Institute of Palaeo-primatology and Human Palaeontology, told BBC News the cats were about the same size as modern lions.

"With our present data, we don't know what precisely the interactions were between a primate and a big carnivore. But probably these interactions were not so friendly," said Professor Vignaud.

He told BBC News: "Sabretooths hunted all mammals; bovids, equids... and primates. The interactions were also more 'psychological', exercising a stress on potential prey. We can't prove it but it's probably important because in that case, primates had to live near closed environments like gallery forest."

While ancient primates like Sahelanthropus tchadensis gave sabretooth cats a wide berth, they may also have depended on these big carnivores - and others - for their survival.

Sabretooths would have hunted large herbivorous mammals, and probably left enough meat on their kills for scavengers like the jackal-sized Hyaenictherium and perhaps even primates like Sahelanthropus.

Some researchers have proposed that Toumai is more closely related to chimpanzees or gorillas. Even if this were the case, the discovery would be of great significance, as virtually no fossil ancestors of these great apes are known from Africa.

http://www.bbc.co.uk/news/science-environment-11979934

Prehistoric first humans in North America were NOT wiped out by a comet

By Niall Firth
Last updated at 5:10 PM on 1st October 2010

The very first humans to live north America were not wiped out by a comet, according to new research.

It had long been believed that that the Clovis people, the prehistoric hunter gatherers who were the first to occupy the continent, had been wiped out by a crash that saw dozens of species made extinct.

The impact triggered a 1,300-year ice age that stretched around the world and the Clovis culture vanished almost overnight in the aftermath, it had been claimed.

But new research challenges the controversial theory by claiming that there is nothing in the archaeological record to suggest an abrupt collapse of Clovis populations.

Writing in the October issue of Current Anthropology, two U.S archaeologists Vance Holliday and David Meltzer say: ‘Whether or not the proposed extraterrestrial impact occurred is a matter for empirical testing in the geological record.

‘Insofar as concerns the archaeological record, an extraterrestrial impact is an unnecessary solution for an archaeological problem that does not exist.’

The comet theory first emerged in 2007 when a team of scientists announced evidence of a large extraterrestrial impact that occurred about 12,900 years ago.

The impact was said to have caused a sudden cooling of the North American climate, killing off mammoths and other megafauna.

It could also explain the apparent disappearance of the Clovis people, whose characteristic spear points vanish from the archaeological record shortly after the supposed impact.

As evidence for the rapid Clovis depopulation, comet theorists point out that very few Clovis archaeological sites show evidence of human occupation after the Clovis.

At the few sites that do, Clovis and post-Clovis artifacts are separated by archaeologically sterile layers of sediments, indicating a time gap between the civilizations.

They believe that is a ‘dead zone’ in the human archaeological record in North America beginning with the comet impact and lasting about 500 years.

But Holliday and Meltzer argue that a lack of later human occupation at Clovis sites is no reason to assume a population collapse.

Holliday said: Single-occupation Paleoindian sites—Clovis or post-Clovis—are the norm.

‘That's because many Paleoindian sites are hunting kill sites, and it would be highly unlikely for kills to be made repeatedly in the exact same spot.

‘So there is nothing surprising about a Clovis occupation with no other Paleoindian zone above it, and it is no reason to infer a disaster.’

In addition, Holliday and Meltzer compiled radiocarbon dates of 44 archaeological sites from across the U.S. and found no evidence of a post-comet gap.

‘Chronological gaps appear in the sequence only if one ignores standard deviations (a statistically inappropriate procedure), and doing so creates gaps not just around [12,900 years ago] but also at many later points in time,’ they write.

Sterile layers separating occupation zones at some sites are easily explained by shifting settlement patterns and local geological processes, the researchers say.

The separation should not be taken as evidence of an actual time gap between Clovis and post-Clovis cultures.

The researcher believe that the disappearance of Clovis spear points is more likely the result of a cultural choice rather than a population collapse.

http://www.dailymail.co.uk/sciencetech/article-1316834/Prehistoric-humans-North-America-NOT-wiped-comet.html#ixzz11n6k76U0

Prehistoric first humans in North America were NOT wiped out by a comet

By Niall Firth
Last updated at 5:10 PM on 1st October 2010

The very first humans to live north America were not wiped out by a comet, according to new research.

It had long been believed that that the Clovis people, the prehistoric hunter gatherers who were the first to occupy the continent, had been wiped out by a crash that saw dozens of species made extinct.

The impact triggered a 1,300-year ice age that stretched around the world and the Clovis culture vanished almost overnight in the aftermath, it had been claimed.

But new research challenges the controversial theory by claiming that there is nothing in the archaeological record to suggest an abrupt collapse of Clovis populations.

Writing in the October issue of Current Anthropology, two U.S archaeologists Vance Holliday and David Meltzer say: ‘Whether or not the proposed extraterrestrial impact occurred is a matter for empirical testing in the geological record.

‘Insofar as concerns the archaeological record, an extraterrestrial impact is an unnecessary solution for an archaeological problem that does not exist.’

The comet theory first emerged in 2007 when a team of scientists announced evidence of a large extraterrestrial impact that occurred about 12,900 years ago.

The impact was said to have caused a sudden cooling of the North American climate, killing off mammoths and other megafauna.

It could also explain the apparent disappearance of the Clovis people, whose characteristic spear points vanish from the archaeological record shortly after the supposed impact.

As evidence for the rapid Clovis depopulation, comet theorists point out that very few Clovis archaeological sites show evidence of human occupation after the Clovis.

At the few sites that do, Clovis and post-Clovis artifacts are separated by archaeologically sterile layers of sediments, indicating a time gap between the civilizations.

They believe that is a ‘dead zone’ in the human archaeological record in North America beginning with the comet impact and lasting about 500 years.

But Holliday and Meltzer argue that a lack of later human occupation at Clovis sites is no reason to assume a population collapse.

Holliday said: Single-occupation Paleoindian sites—Clovis or post-Clovis—are the norm.

‘That's because many Paleoindian sites are hunting kill sites, and it would be highly unlikely for kills to be made repeatedly in the exact same spot.

‘So there is nothing surprising about a Clovis occupation with no other Paleoindian zone above it, and it is no reason to infer a disaster.’

In addition, Holliday and Meltzer compiled radiocarbon dates of 44 archaeological sites from across the U.S. and found no evidence of a post-comet gap.

‘Chronological gaps appear in the sequence only if one ignores standard deviations (a statistically inappropriate procedure), and doing so creates gaps not just around [12,900 years ago] but also at many later points in time,’ they write.

Sterile layers separating occupation zones at some sites are easily explained by shifting settlement patterns and local geological processes, the researchers say.

The separation should not be taken as evidence of an actual time gap between Clovis and post-Clovis cultures.

The researcher believe that the disappearance of Clovis spear points is more likely the result of a cultural choice rather than a population collapse.

http://www.dailymail.co.uk/sciencetech/article-1316834/Prehistoric-humans-North-America-NOT-wiped-comet.html#ixzz11n6k76U0

Did Australian Aborigines reach America first?

by Jacqui Hayes
Cosmos Online
Thursday, 30 September 2010

SYDNEY: Cranial features distinctive to Australian Aborigines are present in hundreds of skulls that have been uncovered in Central and South America, some dating back to over 11,000 years ago.

Evolutionary biologist Walter Neves of the University of São Paulo, whose findings are reported in a cover story in the latest issue of Cosmos magazine, has examined these skeletons and recovered others, and argues that there is now a mass of evidence indicating that at least two different populations colonised the Americas.

He and colleagues in the United States, Germany and Chile argue that first population was closely related to the Australian Aborigines and arrived more than 11,000 years ago.

Cranial morphology

The second population to arrive was of humans of 'Mongoloid' appearance - a cranial morphology distinctive of people of East and North Asian origin - who entered the Americas from Siberia and founded most (if not all) modern Native American populations, he argues.

"The results suggest a clear biological affinity between the early South Americans and the South Pacific population. This association allowed for the conclusion that the Americas were occupied before the spreading of the classical Mongoloid morphology in Asia," Neves says.

Until about a decade ago, the dominant theory in American archaeology circles was that the 'Clovis people' - whose culture is defined by the stone tools they used to kill megafauna such as mammoths - was the first population to arrive in the Americas.

Clovis culture

They were thought to have crossed the Bering Strait from Siberia into Alaska at the end of the last Ice Age, some 10,000 or so years ago, following herds of megafauna across a land bridge created as water was locked up in glaciers and ice sheets.

But in the late 1990s, Neves and his colleagues re-examined a female skeleton that had been excavated in the 1970s in an extensive cave system in Central Brazil known as Lapa Vermelha.

The skeleton - along with a treasure trove of other finds - had been first unearthed by a Brazilian-French archaeological team that disbanded shortly after its leader, Annette Laming-Emperare, died suddenly. A dispute between participants kept the find barely examined for more than a decade.

The oldest female skeleton, dubbed Luzia, is between 11,000 and 11,400 years old. The dating is not exact because the material in the bones used for dating - collagen - has long since degraded; hence, only the layers of charcoal or sediment above and below the skeleton could be dated.

"We believe she is the oldest skeleton in the Americas," Neves said.

Luzia has a very projected face; her chin sits out further than her forehead, and she has a long, narrow brain case, measured from the eyes to the back of the skull; as well as a low nose and low orbits, the space where the eyes sit.

These facial features are indicative of what Neves calls the 'generalised cranial morphology' - the morphology of anatomically modern humans, who first migrated out of Africa more than 100,000 years ago, and made it as far as Australia some 50,000 years ago, and Melanesia 40,000 years ago.

New finds in seven sites

When Neves first announced his discovery of Luzia in the late 1990s, he faced criticism from a number of archaeologists, who claimed the dating was not accurate. He has since returned to excavate four other sites, and is still cataloguing skeletons from the most recent dig.

In total, there are now hundreds of skeletons with the cranial morphology similar to Australian Aborigines, found in seven sites - as far north as Florida in the United States to Palli Aike in southern Chile.

In 2005, he published a paper in the U.S journal, Proceedings of the National Academy of Sciences, analysing the characteristics of a further 81 skeletons he recovered from one of four sites, in which he said strengthened his argument that there were migrations to the Americas from at least two major populations.

Not related to Native Americans

In June 2010 in the journal PLoS ONE, Neves and colleagues Mark Hubbe of Chile's Northern Catholic University and Katerina Harvati from Germany's University of Tübingen, showed that it was not possible for the Aborigine-like skeletons to be the direct ancestors of the Native Americans.

Nor was it possible for the two populations to share a last common ancestor at the time of the first entrance into the continent, they argued, based on the 57 cranial measurements that can be made on a skull.

So far, almost all DNA studies of Native Americans points to a single entry from Siberia. This may mean that the original population died out, or simply that DNA studies have been too narrow, argue a number of archaeologists.

Genetic evidence needed

"The lack of a perfect match between morphological and molecular information can be easily explained by a very frequent event in molecular evolution: loss of DNA lineages throughout time," Neves says.

"At first, I thought there had been a complete replacement of the population [in South America]," just as there was a replacement of a similar population in East Asia during the Pleistocene/Holocene boundary.

However, he now thinks that the original people were, at least partly, absorbed into the colonising groups. "I have not detected anything that could say they interbred [such as skulls exhibiting mixed cranial features].

"But I think we will. It would be unlikely if these people lived side-by-side for 10,000 years and did not interbreed," he added.

Neves is now calling on molecular archaeologists - experts in the recovery and analysis of DNA - to turn their focus to the question of who Luzia's Aborigine-like people were.

http://www.cosmosmagazine.com/news/3774/did-australian-aborigines-reach-america-first?page=0%2C0
(Submitted by Terry W. Colvin)

Did Australian Aborigines reach America first?

by Jacqui Hayes
Cosmos Online
Thursday, 30 September 2010

SYDNEY: Cranial features distinctive to Australian Aborigines are present in hundreds of skulls that have been uncovered in Central and South America, some dating back to over 11,000 years ago.

Evolutionary biologist Walter Neves of the University of São Paulo, whose findings are reported in a cover story in the latest issue of Cosmos magazine, has examined these skeletons and recovered others, and argues that there is now a mass of evidence indicating that at least two different populations colonised the Americas.

He and colleagues in the United States, Germany and Chile argue that first population was closely related to the Australian Aborigines and arrived more than 11,000 years ago.

Cranial morphology

The second population to arrive was of humans of 'Mongoloid' appearance - a cranial morphology distinctive of people of East and North Asian origin - who entered the Americas from Siberia and founded most (if not all) modern Native American populations, he argues.

"The results suggest a clear biological affinity between the early South Americans and the South Pacific population. This association allowed for the conclusion that the Americas were occupied before the spreading of the classical Mongoloid morphology in Asia," Neves says.

Until about a decade ago, the dominant theory in American archaeology circles was that the 'Clovis people' - whose culture is defined by the stone tools they used to kill megafauna such as mammoths - was the first population to arrive in the Americas.

Clovis culture

They were thought to have crossed the Bering Strait from Siberia into Alaska at the end of the last Ice Age, some 10,000 or so years ago, following herds of megafauna across a land bridge created as water was locked up in glaciers and ice sheets.

But in the late 1990s, Neves and his colleagues re-examined a female skeleton that had been excavated in the 1970s in an extensive cave system in Central Brazil known as Lapa Vermelha.

The skeleton - along with a treasure trove of other finds - had been first unearthed by a Brazilian-French archaeological team that disbanded shortly after its leader, Annette Laming-Emperare, died suddenly. A dispute between participants kept the find barely examined for more than a decade.

The oldest female skeleton, dubbed Luzia, is between 11,000 and 11,400 years old. The dating is not exact because the material in the bones used for dating - collagen - has long since degraded; hence, only the layers of charcoal or sediment above and below the skeleton could be dated.

"We believe she is the oldest skeleton in the Americas," Neves said.

Luzia has a very projected face; her chin sits out further than her forehead, and she has a long, narrow brain case, measured from the eyes to the back of the skull; as well as a low nose and low orbits, the space where the eyes sit.

These facial features are indicative of what Neves calls the 'generalised cranial morphology' - the morphology of anatomically modern humans, who first migrated out of Africa more than 100,000 years ago, and made it as far as Australia some 50,000 years ago, and Melanesia 40,000 years ago.

New finds in seven sites

When Neves first announced his discovery of Luzia in the late 1990s, he faced criticism from a number of archaeologists, who claimed the dating was not accurate. He has since returned to excavate four other sites, and is still cataloguing skeletons from the most recent dig.

In total, there are now hundreds of skeletons with the cranial morphology similar to Australian Aborigines, found in seven sites - as far north as Florida in the United States to Palli Aike in southern Chile.

In 2005, he published a paper in the U.S journal, Proceedings of the National Academy of Sciences, analysing the characteristics of a further 81 skeletons he recovered from one of four sites, in which he said strengthened his argument that there were migrations to the Americas from at least two major populations.

Not related to Native Americans

In June 2010 in the journal PLoS ONE, Neves and colleagues Mark Hubbe of Chile's Northern Catholic University and Katerina Harvati from Germany's University of Tübingen, showed that it was not possible for the Aborigine-like skeletons to be the direct ancestors of the Native Americans.

Nor was it possible for the two populations to share a last common ancestor at the time of the first entrance into the continent, they argued, based on the 57 cranial measurements that can be made on a skull.

So far, almost all DNA studies of Native Americans points to a single entry from Siberia. This may mean that the original population died out, or simply that DNA studies have been too narrow, argue a number of archaeologists.

Genetic evidence needed

"The lack of a perfect match between morphological and molecular information can be easily explained by a very frequent event in molecular evolution: loss of DNA lineages throughout time," Neves says.

"At first, I thought there had been a complete replacement of the population [in South America]," just as there was a replacement of a similar population in East Asia during the Pleistocene/Holocene boundary.

However, he now thinks that the original people were, at least partly, absorbed into the colonising groups. "I have not detected anything that could say they interbred [such as skulls exhibiting mixed cranial features].

"But I think we will. It would be unlikely if these people lived side-by-side for 10,000 years and did not interbreed," he added.

Neves is now calling on molecular archaeologists - experts in the recovery and analysis of DNA - to turn their focus to the question of who Luzia's Aborigine-like people were.

http://www.cosmosmagazine.com/news/3774/did-australian-aborigines-reach-america-first?page=0%2C0
(Submitted by Terry W. Colvin)

Neanderthals were able to 'develop their own tools'

24 September 2010
By Katia Moskvitch
Science reporter, BBC News

Neanderthals were keen on innovation and technology and developed tools all on their own, scientists say.

A new study challenges the view that our close relatives could advance only through contact with Homo sapiens.

The team says climate change was partly responsible for forcing Neanderthals to innovate in order to survive.

The research is set to appear in the Journal of Archaeological Method and Theory in December.

"Basically, I am rehabilitating Neanderthals," said Julien Riel-Salvatore, assistant professor of anthropology at the University of Colorado in Denver, who led the seven-year study.

"They were far more resourceful than we have given them credit for."

Vanished culture

Neanderthals were first discovered in Germany's Neander Valley in 1856.

It is believed that they lived in Europe and parts of Asia. Close examination of the found fossils shows that they shared 99.5-99.9% of modern humans' DNA, which makes them our closest relatives.

They had short, muscular bodies, large brains, prominent facial features and barrel chests.

Neanderthals split from our evolutionary line some 500,000 years ago, and disappeared off the face of the Earth about 30,000 years ago.

Since the first discovery, anthropologists have been trying to crack the mystery of the vanished culture, also debating whether or not Neanderthals were evolving on their own or through contact with Homo sapiens.

During the research, Dr Riel-Salvatore and his colleagues examined Neanderthal sites across Italy.

About 42,000 years ago, Homo sapiens and Neanderthals were already living in the northern and central parts of the area.

At that time, an entirely new group appeared in the south.

The researchers believe that the southerners were also Neanderthals, of a culture named Uluzzian.

Dr Riel-Salvatore's team was astonished to find quite a few innovations throughout the area, even though the Uluzzians were isolated from Homo sapiens.

They discovered projectile points, ochre, bone tools, ornaments and possible evidence of fishing and small game hunting.

"My conclusion is that if the Uluzzian is a Neanderthal culture, it suggests that contacts with modern humans are not necessary to explain the origin of this new behaviour.

"This stands in contrast to the ideas of the past 50 years that Neanderthals had to be acculturated to [modern] humans to come up with this technology.

"When we show Neanderthals could innovate on their own, it casts them in a new light.

"It 'humanises' them, if you will."

Brothers?

The researchers believe that one reason that forced Neanderthals to innovate was a shift in climate.

When the area where they were living started to become increasingly open and arid, they had no choice but to adapt - or die out.

"The fact that Neanderthals could adapt to new conditions and innovate shows they are culturally similar to us," said Dr Riel-Salvatore.

He added that they were also similar biologically, and should be considered a subspecies of human rather than a different species.

"My research suggests that they were a different kind of human, but humans nonetheless.

"We are more brothers than distant cousins."

http://www.bbc.co.uk/news/science-environment-11408298

Neanderthals were able to 'develop their own tools'

24 September 2010
By Katia Moskvitch
Science reporter, BBC News

Neanderthals were keen on innovation and technology and developed tools all on their own, scientists say.

A new study challenges the view that our close relatives could advance only through contact with Homo sapiens.

The team says climate change was partly responsible for forcing Neanderthals to innovate in order to survive.

The research is set to appear in the Journal of Archaeological Method and Theory in December.

"Basically, I am rehabilitating Neanderthals," said Julien Riel-Salvatore, assistant professor of anthropology at the University of Colorado in Denver, who led the seven-year study.

"They were far more resourceful than we have given them credit for."

Vanished culture

Neanderthals were first discovered in Germany's Neander Valley in 1856.

It is believed that they lived in Europe and parts of Asia. Close examination of the found fossils shows that they shared 99.5-99.9% of modern humans' DNA, which makes them our closest relatives.

They had short, muscular bodies, large brains, prominent facial features and barrel chests.

Neanderthals split from our evolutionary line some 500,000 years ago, and disappeared off the face of the Earth about 30,000 years ago.

Since the first discovery, anthropologists have been trying to crack the mystery of the vanished culture, also debating whether or not Neanderthals were evolving on their own or through contact with Homo sapiens.

During the research, Dr Riel-Salvatore and his colleagues examined Neanderthal sites across Italy.

About 42,000 years ago, Homo sapiens and Neanderthals were already living in the northern and central parts of the area.

At that time, an entirely new group appeared in the south.

The researchers believe that the southerners were also Neanderthals, of a culture named Uluzzian.

Dr Riel-Salvatore's team was astonished to find quite a few innovations throughout the area, even though the Uluzzians were isolated from Homo sapiens.

They discovered projectile points, ochre, bone tools, ornaments and possible evidence of fishing and small game hunting.

"My conclusion is that if the Uluzzian is a Neanderthal culture, it suggests that contacts with modern humans are not necessary to explain the origin of this new behaviour.

"This stands in contrast to the ideas of the past 50 years that Neanderthals had to be acculturated to [modern] humans to come up with this technology.

"When we show Neanderthals could innovate on their own, it casts them in a new light.

"It 'humanises' them, if you will."

Brothers?

The researchers believe that one reason that forced Neanderthals to innovate was a shift in climate.

When the area where they were living started to become increasingly open and arid, they had no choice but to adapt - or die out.

"The fact that Neanderthals could adapt to new conditions and innovate shows they are culturally similar to us," said Dr Riel-Salvatore.

He added that they were also similar biologically, and should be considered a subspecies of human rather than a different species.

"My research suggests that they were a different kind of human, but humans nonetheless.

"We are more brothers than distant cousins."

http://www.bbc.co.uk/news/science-environment-11408298