QuoteReplyTopic: Anthropology news updates Posted: 12-Apr-2013 at 01:41
How 2-Million-Year-Old Ancestor Moved: Sediba's Ribcage and Feet Were Not Suitable for Running
Reconstruction of Au. sediba.
Researchers at Wits University in South Africa, including Peter Schmid from the University of Zurich, have described the anatomy of a single early hominin in six new studies.Australopithecus sediba was discovered near Johannesburg in 2008. The studies in Sciencedemonstrate how our 2-million-year-old ancestor walked, chewed and moved.
The fossils discovered four years ago in Malapa near Johannesburg show a mixture of primitive features of australopiths and advanced features of later human species. The researchers led by Prof Lee Berger of Wits University are therefore of the opinion that the new species is currently the best candidate for a direct ancestor of our own genusHomo. Researchers are now presenting new studies, including those of Peter Schmid, who taught and did research at the University of Zurich until he retired. Also involved were UZH students Nakita Frater, Sandra Mathews and Eveline Weissen.
Schmid has described the remains ofAu. sediba's thorax. "They show a narrow upper ribcage, as the large apes have such as orangutans, chimpanzees and gorillas," says Peter Schmid. The human thorax on the other hand is uniformly cylindrical. Along with the largely complete remnants of the pectoral girdle, we see the morphological picture of a conical ribcage with a raised shoulder joint, which looks like a permanent shrug. The less well-preserved elements of the lower thorax on the other hand indicate a slim waist, similar to that of a human being.
Conical ribcage makes it difficult to swing arms when walking
The narrow upper thorax of apes enables them to move the shoulder blade, which is important for climbing and brachiation in trees. Its conical shape makes it difficult, however, to swing their arms when walking upright or running, plus they were a similar length to an ape's. This is why Schmid assumes thatAu. sediba was not able to walk or run on both feet as well as humans. "They probably couldn't run over longer distances, especially as they were unable to swing their arms, which saves energy," says Schmid.
An examination of the lower extremities shows a heel, metatarsus, knee, hips and back, which are unique and unprecedented. Sediba must have walked with feet turned sharply inwards. This inward turn distinguishes it from other australopiths. The conclusion to be drawn is that our early ancestors were able to move around in a different way................
Earliest Archaeological Evidence of Sustained Carnivory by Human Ancestors
Located on the southern shores of the Winam Gulf of Lake Victoria in southwestern Kenya, theKanjera Southarchaeological site has now yielded finds that, according to a recent study published May 1, 2013 in the open-access scientific journal PLOS ONE, provide strong material evidence that hominins (early human ancestors) practiced "persistent carnivory", or acquired, transported, processed and presumably consumed animals on a regular basis, about 2 million years ago. The finding helps to address the dearth of available data or evidence that would bridge the gap between 2.6 mya, when the earliest stone tools are thought to have emerged, and 1.8 mya, the date after which the faunal evidence becomes more plentiful.
The team of scientists studied three large, well-preserved, and stratified ancient faunal assemblages (a collection of associated animal remains) that date to ~2.0 Ma, assemblages that formed on an ancient grassy plain located between a freshwater lake and wooded slopes of nearby hills and mountains on the Homa peninsula, a landmass distinguished by the Homa volcano. In three select excavations of 1m ×1m squares, they recovered several thousand well-preserved faunal specimens using lightweight hammers and awls. The faunal remains consisted of fossilized bone remnants of numerous small bovids [cloven-hoofed, ruminantmammals such as gazelles] and a smaller number of medium-sized bovids. What they found was clear evidence of "bone modification", meaning fossil bones bearing cut marks and/or hammerstone percussion damage made presumably by tool-bearing hominins. All remains were located within a stratified sequence of 3 separate archaeofaunal-bearing deposits, or beds, labeled KS (Kanjera South)-1 through KS-3. Report the researchers, "These specimens provide unambiguous evidence of hominin processing of bovid remains, and indicate a functional relationship between artifactual and faunal materials".[1]
Location of Kanjera along the modern shoreline of Lake Victoria, East Africa. (A) Kanjera lies to the immediate northeast of Homa Mountain, a volcanic complex active from the middle Miocene to the Pleistocene. The Winam Gulf fills the western end of the Nyanza Rift, an E-W graben with origins in the early Miocene. (B) Beds KS-1 through KS-3 of the Kanjera Formation (Southern Member) sample floodplain and low-aspect channel contexts originally deposited between the mountain and the nearby shores of a shallow lake. Satellite imagery from USGS and NASA. doi:10.1371/journal.pone.0062174.g001 Source: Ferraro JV, Plummer TW, Pobiner BL, Oliver JS, Bishop LC, et al. (2013) Earliest Archaeological Evidence of Persistent Hominin Carnivory. PLoS ONE 8(4): e62174. doi:10.1371/journal.pone.0062174
Bone surface modifications. (A) KJS 7472, a small bovid metatarsal from KS-2 bearing cut marks; (B) KJS 7379, a medium-sized bovid humerus from KS3 bearing pair of hammerstone notches, the specimen is also cut-marked (not figured); (C) KJS 5447, a mammal limb bone shaft fragment from KS-2 with percussion pit and striae, the specimen is also cut-marked (not figured); (D) KJS 2565, a small bovid femur from KS-2 with numerous cut marks. Scale is 1 cm in panels (A-D); 1 mm in the panel (D) close-up. Specimen numbers are field designations, not KNM accession numbers. doi:10.1371/journal.pone.0062174.g002 Source: Ferraro JV, Plummer TW, Pobiner BL, Oliver JS, Bishop LC, et al. (2013) Earliest Archaeological Evidence of Persistent Hominin Carnivory. PLoS ONE 8(4): e62174. doi:10.1371/journal.pone.0062174
The findings are important because, although the earliest known flaked lithic technology (dated to around ~2.6 Ma), found at such sites as Gona in Ethiopia, has been thought to suggest early hominin involvement with animals in the form of scavenging or hunting and consumption, the associated faunal evidence, or "smoking gun", has been lacking prior to about 1.8 Ma, making it difficult to test this suggestion and related hypotheses using the zooarchaeological record.
The study has also provided tantalizing clues to the nature of the hominin activity. "Surface modification studies and skeletal element analyses indicate that hominins acquired most or all of these remains relatively early in their resource lives (i.e., in a complete or relatively complete state)", report the researchers, "providing foragers with access to meat, organ, and within-bone food resources. Given their overall abundance and skeletal representation, unambiguous evidence of their butchery, and their presumed limited availability as potentially-scavengable resources in a grassland setting, the small bovid remains at KJS [Kanjera South] may reflect the earliest archaeological evidence of hominin hunting activities".[1]
The nature of the foraging activity was not confined to hunting, according to the researchers. Scavenging, long thought by scientists to be a possible carnivorous food-gathering practice by early human ancestors, was also a part of their repertoire. "......There is clear evidence that hominins acquired the postcranial remains of at least some medium-sized individuals relatively early in their resource lives (i.e., with at least some adhering flesh)........The disproportionate abundance of medium-sized heads, however, likely reflects a separate but complementary foraging activity, one specifically focused on scavenging these remains for their internal food resources (e.g., brain tissues). This latter portion of the record may represent the earliest archaeological evidence of a distinct hominin scavenging strategy". [1]
The acquirement, processing and consumption of meat from animals is theorized by many evolutionists as a critical element in the requirement for high-protein, high-fat, high-energy foods necessary to support the growth or evolution of the distinctive qualities of humans as compared to other animals, such as the larger brain. The development of systematic and sustained carnivory by early humans (hominins) at an early stage in the evolution of humans has been considered a central element in models of human evolution. Conclude the authors of the study: ".......Our findings are directly relevant to a number of interrelated debates within Oldowan hominin paleobiology. These include many of the formative issues of the field, including those that explore the possible relationship(s) between the emergence of persistent hominin carnivory and the evolution of novel social and foraging ecologies, brain expansion, range extension, life history adaptations, and, potentially, the interplay of some or all of these topics as they relate to the emergence and early evolutionary history of the genus Homo". [1]
Excavations at Kanjera South, which have been co-directed by Tom Plummer, an Associate Professor in the Anthropology Department at Queens College, City University of New York, along with Dr. Richard Potts of the Human Origins Program of the Smithsonian Institution, have yielded one of the largest collectons of Oldowan artifacts with associated faunal remains. The artifacts are suggested to have been produced and used by early members of the genus Homo (a hominin genus more directly related to and ancestral to modern humans), such as Homo habilis and Homo erectus.
EARLIEST EVIDENCE OF HUMAN ANCESTORS HUNTING AND SCAVENGING
Small antelope leg bone with cut marks, indicative of early human butchery practices.
Beginning around two million years ago, early stone tool-making humans, known scientifically as Oldowan hominin, started to exhibit a number of physiological and ecological adaptations that required greater daily energy expenditures, including an increase in brain and body size, heavier investment in their offspring and significant home-range expansion.
Demonstrating how these early humans acquired the extra energy they needed to sustain these shifts has been the subject of much debate among researchers.
A recent study led by Joseph Ferraro, Ph.D., assistant professor of anthropology at Baylor, offers new insight in this debate with a wealth of archaeological evidence from the two million-year-old site of Kanjera South (KJS), Kenya. The study’s findings were recently published in PLOS One.
Facilitated brain expansion
“Considered in total, this study provides important early archaeological evidence for meat eating, hunting and scavenging behaviour -cornerstone adaptations that likely facilitated brain expansion in human evolution, movement of hominins out of Africa and into Eurasia, as well as important shifts in our social behaviour, anatomy and physiology,” Ferraro said.
Aerial view of the archaeological site Kanjera South, Kenya. Photo courtesy of Thomas Plummer.
Located on the shores of Lake Victoria, KJS contains “three large, well-preserved, stratified” layers of animal remains. The research team worked at the site for more than a decade, recovering thousands of animal bones and rudimentary stone tools.
Increased reliance on meat eating
According to researchers, hominins at KJS met their new energy requirements through an increased reliance on meat eating. Specifically, the archaeological record at KJS shows that hominins acquired an abundance of nutritious animal remains through a combination of both hunting and scavenging behaviours. The KJS site is the earliest known archaeological evidence of these behaviours.
“Our study helps inform the ‘hunting vs. scavenging’ debate in Palaeolithic archaeology. The record at KJS shows that it isn’t a case of either/or for Oldowan hominins two million years ago. Rather hominins at KJS were clearly doing both,” Ferraro said.
Transported as whole carcasses
The fossil evidence for hominin hunting is particularly compelling. The record shows that Oldowan hominins acquired and butchered numerous small antelope carcasses. These animals are well represented at the site by most or all of their bones from the tops of their head to the tips of their hooves, indicating to researchers that they were transported to the site as whole carcasses.
Many of the bones also show evidence of cut marks made when hominins used simple stone tools to remove animal flesh. Some bones also bear evidence that hominins used fist-sized stones to break them open to acquire bone marrow.
In addition, modern studies in the Serengeti–an environment similar to KJS two million years ago–have also shown that predators completely devour antelopes of this size within minutes of their deaths. As a result, hominins could only have acquired these valuable remains on the savanna through active hunting.
Wildebeest-sized antelopes
The site also contains a large number of isolated heads of wildebeest-sized antelopes. In contrast to small antelope carcasses, the heads of these somewhat larger individuals are able to be consumed several days after death and could be scavenged, as even the largest African predators like lions and hyenas were unable to break them open to access their nutrient-rich brains.
“Tool-wielding hominins at KJS, on the other hand, could access this tissue and likely did so by scavenging these heads after the initial non-human hunters had consumed the rest of the carcass,” Ferraro said. “KJS hominins not only scavenged these head remains, they also transported them some distance to the archaeological site before breaking them open and consuming the brains. This is important because it provides the earliest archaeological evidence of this type of resource transport behaviour in the human lineage.”
Race IQ – Game Over: It was always all about wealth
AtThe American Conservativein July 2012, Ron Unz publishedRace, IQ, and Wealth, and after some responses put upUnz on Race/IQ: Response to Lynn and Nyborgon his blog. Unz’s position, which came from analyzing the very data most cited to support the racialist position on Race IQ linkages:
Essentially, I am proposing that the enormously large differences in population IQ . . . are primarily due to factors of social environment–poverty, education, rural deprivation.
If Unz sticks to his guns–and every indication is that racialist rebuttals are only hardening his position–this is game over for Race IQ. Finally.
Of course, Ron Unz is hardly a household name in anthropology, and I’m grateful to Henry Harpending for continuing a conversation about race (taking off from my post on teaching race anthropologically) which led me to this material.
Second, Ron Unz matters on Race IQ because he is using the numbers from people who had been elaborating the Bell Curve argument that IQ is causal to social and class differences rather than a related consequence of those differences. Of course most of anthropology and mainstream academics probably did not even know this work was proceeding. However, it should be noted–as I did in Jared Diamond won’t beat Mitt Romney–that for the people who wanted to see Race IQ connections, Jared Diamond and Stephen Jay Gould were extremely weak rebuttals. One could even say that those who cited Diamond or Gould would be dismissed, in a kind of “that’s all you have?” sort of way. But this is obviously different.
Third, Ron Unz signals game over for Race IQ because he seems to be getting so attacked from his own. In addition to the Cochran exchange above, Unz ends his blog-post with this:
Finally, I do regret the nasty personal attacks and misrepresentations which Nyborg, Lynn, and many of their allies have endured. But given the many hundreds of caustic insults and harsh denunciations I have recently received from Lynn’s energetic admirers, I would suggest that there might be two sides to this story.
As I said at the beginning, I’m not sure whether Unz will stick to his guns on this one–there are a number of rebuttals circulating. But the rebuttals seem mostly to be on the more extreme racialist blogs, and Unz doesn’t seem to be buying them. Without Unz’s support, these writings can only become the most marginalized of the already marginal.
Now this doesn’t mean Unz is going to pop over here and give me a fellowship. In his writings, he praises the racialists for being the only ones who are combing through the data and providing a serious response. He also is obliged to take a few whacks at Gould and his ilk. But let’s get real–the only reason the racialists are combing the quantitative data is to try and poke holes and mount a rebuttal. For the rest of us–who already knew that what we measure as IQ is in large part due to “factors of social environment–poverty, education, rural deprivation,” we can declare game over on Race IQ–see Unz 2012.
Of course, this also doesn’t mean it’s over for inequality and racism. Ending the hardline race IQ argument doesn’t at all change the facts-on-the-ground where things are as unequal as ever. One of the racialist lines has always been to observe how the average white/black IQ differential has hardly budged in 50 years. With Unz’s article safely in hand, this is obviously and easily explained: the average white/black wealth differential has also hardly budged in 50 years. The sociological data–an update by one of the authors of Black Wealth / White Wealth: A New Perspective on Racial Inequality and from before the Great Recession–indicate The Racial Wealth Gap Increases Fourfold:
New evidence reveals that the wealth gap between white and African American families has more than quadrupled over the course of a generation. Using economic data collected from the same set of families over 23 years (1984-2007), we find that the real wealth gains and losses of families over that time period demonstrate the stampede toward an escalating racial wealth gap.
Finally, we should also be aware that national IQ averages and white/black IQ averages in the U.S. are certainly obscuring inequality dynamics within these groups. We may already be seeing the effects of inequality in the U.S.:
“We have moved from a society in the 1950s and 1960s, in which race was more consequential than family income, to one today in which family income appears more determinative of educational success than race,” said Sean F. Reardon, a Stanford University sociologist. Professor Reardon is the author of a study that found that the gap in standardized test scores between affluent and low-income students had grown by about 40 percent since the 1960s, and is now double the testing gap between blacks and whites. (Tavernise 2012, Education Gap Grows Between Rich and Poor)
I would predict that we will in not too long start to see such a divergence between rich white and poor white IQ scores that it will make a mockery of race IQ calculations. Similarly, on an international level there is the rise of Brazil, India, and China–and very intriguingly, even Africa–The Next Asia Is Africa: Inside the Continent’s Rapid Economic Growth. All developments which will further confound the usual race IQ predictions. Maybe not all good developments, to be sure, but at least we should finally be able to bid goodbye to the hardline race IQ peddlers.
Prehistoric ear bones could lead to evolutionary answers
Tiny ear bones (from left) the incus, stapes, and malleus could provide big clues to human evolution.
The tiniest bones in the human body – the bones of the middle ear – could provide huge clues about our evolution and the development of modern-day humans, according to a study by a team of researchers that include a Texas A&M University anthropologist.
Darryl de Ruiter, a professor in the Department of Anthropology at Texas A&M, and colleagues from Binghamton University (the State University of New York) and researchers from Spain and Italy have published their work in the current issue ofPNAS (Proceedings of the National Academy of Science).
The team examined the skull of a hominin believed to be about 1.9 million years old and found in a cave called Swartkrans, in South Africa. Of particular interest to the team were bones found in the middle ear, especially one called the malleus. It and the other ear bones – the incus and the stapes – together show a mixture of ape-like and human-like features, and represent the first time all three bones have been found together in one skull.
The malleus appears to be very human-like, the findings show, while the incus and stapes resemble those of a more chimpanzee-like, or ape-like creature. Since both modern humans and our early ancestors share this human-like malleus, the changes in this bone must have occurred very early in our evolutionary history.
"The discovery is important for two reasons," de Ruiter explains.
"First, ear ossicles are fully formed and adult-sized at birth, and they do not undergo any type of anatomical change in an individual lifetime. Thus, they are a very close representation of genetic expression. Second, these bones show that their hearing ability was different from that of humans – not necessarily better or worse, but certainly different.
"They are among the rarest of fossils that can be recovered," de Ruiter adds.
"Bipedalism (walking on two feet) and a reduction in the size of the canine teeth have long been held to be 'hallmarks of humanity' since they seem to be present in the earliest human fossils recovered to date. Our study suggests that the list may need to be updated to include changes in the malleus as well."
de Ruiter recently authored a series of papers in Science magazine that demonstrate the intermediate nature of the closely related species, Australopithecus sediba, and provide strong support that this species lies rather close to the ancestry of Homo sapiens. The current study could yield additional new clues to human development and answer key questions of the evolution of the human lineage.
The earliest known cave paintings fuel arguments about whether Neanderthals were the mental equals of modern humans.
Spots and stencils in El Castillo cave, Spain — one at least 40,800 years old — might be the handiwork of Neanderthals.
In a damp Spanish cave, Alistair Pike applies a small grinder to the world's oldest known paintings. Every few minutes, the dentist-drill sound stops and Pike, an archaeologist from the University of Southampton, UK, stands aside so that a party of tourists can admire the simple artwork — hazy red disks, stencilled handprints, the outlines of bison — daubed on the cave wall tens of thousands of years ago. He hopes that the visitors won't notice the small scuff marks he has left.
In fact, Pike's grinder — and the scalpel that he wields to scrape off tiny samples — is doing no harm to the actual paintings, and he is working with the full approval of the Spanish authorities. Pike is after the crust of calcite that has built up over the millennia from groundwater dripping down the wall. The white flecks that he dislodges hold a smattering of uranium atoms, whose decay acts as a radioactive clock. A clock that has been ticking ever since the calcite formed on top of the art.
The results of an earlier round of sampling in El Castillo cave, published last June1, showed that the oldest of the paintings, a simple red spot, dates to at least 40,800 years ago, roughly when the first modern humans reached western Europe. Pike and his colleagues think that when they analyse the latest samples, the paintings may turn out to be older still, perhaps by thousands of years — too old to have been made by modern humans. If so, the artists must have been Neanderthals, the brawny, archaic people who were already living in Europe.
The answer won't be known for at least a year, but if it favours the Neanderthals, it could tip — if not resolve — a debate that has rumbled for decades: did the Neanderthals, once caricatured as brute cavemen, have minds like our own, capable of abstract thinking, symbolism and even art? It is one of the most haunting questions about the people who once shared a continent with us, then mysteriously vanished.
An early date for the paintings would also be a vindication for the slight, dark-haired man watching as Pike works: João Zilhão, who has emerged as the leading advocate for Neanderthals, relentlessly pressing the case that these ice-age Europeans were our cognitive equals. Zilhão, an archaeologist at the Catalan Institution for Research and Advanced Studies at the University of Barcelona in Spain, believes that other signs of sophisticated Neanderthal culture have already proved his point. But he is willing to debate on his opponents' terms. “To my mind, we don't need that evidence,” he says of the paintings. “But I guess for many of my colleagues this would be the smoking gun.”
The front line in the Neanderthal wars runs through another cave: Grotte du Renne, 1,000 kilometres away in central France. As early as the 1950s, excavations there unearthed a collection of puzzling artefacts. Among them were bone awls, distinctive stone blades and palaeolithic baubles — the teeth of animals such as foxes or marmots, grooved or pierced so that they could be worn on a string. They were buried beneath artefacts typical of the first modern humans in Europe, suggesting that these objects were older. A startling possibility loomed: that artefacts of this style, collectively known as the Châtelperronian industry, were made by Neanderthals.
Close cousins of modern humans, Neanderthals evolved in western Eurasia and had Europe to themselves for more than 200,000 years, enduring several ice ages. In spite of their survival skills and big brains — comparable to our own — they had never been linked to sophisticated tools of this kind, or to ornaments. Yet in 1980, archaeologists reported finding a Neanderthal skeleton among Châtelperronian tools at another site in France2. And in 1996, French palaeoanthropologist Jean-Jacques Hublin and his colleagues reported that a skull fragment from the ornament layer in the Grotte du Renne was unmistakably Neanderthal3.
Ever since then, the Grotte du Renne has been exhibit A in the case that Neanderthals, like ourselves, trafficked in symbols, using ornaments as badges of identity for individuals or groups.
Hublin himself did not go that far. He suggested that the Neanderthals had fallen under the spell of strange new neighbours: modern humans, who were thought to have reached Europe around the time of the Châtelperronian industry. Neanderthals might have acquired the ice-age bling from modern humans, or made the pendants themselves under the influence of the new arrivals.
That conclusion infuriated Zilhão, turning him into the passionate advocate he is today. He questioned the evidence that modern humans were already on the scene and detected a bias against our extinct cousins. “Why was the equally if not more legitimate hypothesis — that the Neanderthals themselves had been the authors of this stuff and made it for their own use — not even considered?” asks Zilhão.
On a visit to rock-art sites in Portugal, he discussed the paper with Francesco d'Errico, an archaeologist who is now at the University of Bordeaux in France. D'Errico had the same reaction, Zilhão recalls. “And he said: 'OK, let's do something about it.'” Since then, the pair has fought a two-front war, advancing evidence for Neanderthal capabilities while challenging studies that reserve symbolism and abstract thinking for modern humans.
Unknown artists
More than 15 years later, the Grotte du Renne continues to be a battleground. Since 2010, three papers have given duelling interpretations of the artefact-bearing layers. In the first, a group led by dating expert Thomas Higham of the University of Oxford, UK, used new carbon dates to argue that the layers were scrambled, mixing older remains with younger4. If that was correct, said Higham's team, the relics adjacent to the telltale skull fragment might not have belonged to Neanderthals after all.
Within months, Zilhão, d'Errico and their colleagues fired back with an analysis5 of how artefacts of different types were distributed in the Grotte du Renne, concluding that the layers were undisturbed and that the Neanderthal link could be trusted. A group led by Hublin (now at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany) presented its own dates last year, backing Zilhão's claim6. But Hublin still denied the Neanderthals full credit. Neanderthals did make the objects, now dated to between 45,000 and 40,000 years ago, he said — but only after they encountered modern humans. And this time he had fresh evidence to draw on.
Carbon dates measured by Higham and others at caves in Italy, Britain and Germany suggest that modern humans began expanding into Europe as early as 45,000 years ago, several thousand years earlier than was thought (see Nature485, 27–29; 2012). Zilhão strenuously disputes those claims, doubting whether the shells or animal bones used for dating truly reflect the age of the human fossils at the sites, or whether the human remains are modern. “The evidence to show an early presence of modern humans in Europe is worse today than it was 20 years ago,” he declares.
Hublin, however, has no doubt that our ancestors had already entered the picture when Neanderthals in France began making bone awls and animal-tooth pendants. To assume that Neanderthals invented these technologies on their own is to accept “an incredible coincidence”, he says. “Just as modern humans arrive with these things in their pocket — bingo!”
Like minds
Despite the stalemate, Zilhão says that the record of Neanderthal behaviour tens of thousands of years before modern humans arrived in Europe proves his point (see 'Minds at work'). Neanderthals are believed to have buried their dead, suggesting that they had some kind of spirituality. They made glue for securing spear points by heating birch sap while protecting it from the air, a feat that even modern experimental archaeologists have trouble replicating. Many Neanderthal sites include lumps of pigment — red ochre and black manganese — that sometimes seem to be worn down like stone-age crayons. Zilhão and others think that the Neanderthals painted themselves, creating striking patterns on their pale, northern skin that were every bit as symbolic as the art and ornaments of modern humans.
“You don't need to have shell beads, you don't need to have artefacts with graphical representation to have behaviour that can be defined archaeologically as symbolic,” he says. “Burying your dead is symbolic behaviour. Making sophisticated chemical compounds in order to haft your stone tools implies a capacity to think in abstract ways, a capacity to plan ahead, that's fundamentally similar to ours.”..............
A set of new studies from the University of Utah and elsewhere found that human ancestors and relatives started eating an increasingly grassy diet 3.5 million years ago. The studies included analysis of tooth enamel from fossils of several early African humans, their ancestors and extinct relatives, some of which are shown here. Top left: Paranthropus bosei, 1.7 million years ago. Top right: Homo sapiens, 10,000 years ago. Center left: Paranthropus aethiopicus, 2.3 million years ago. Center right: Homo ergaster, 1.6 million years ago. Bottom left: Kenyanthropus platyops, 3.3 million years ago. Bottom center: lower jaw from Australopithecus anamensis, 4 million years ago. Bottom right: Homo rudolfensis, 1.9 million years ago.
Most apes eat leaves and fruits from trees and shrubs. New studies spearheaded by the University of Utah show that human ancestors expanded their menu 3.5 million years ago, adding tropical grasses and sedges to an ape-like diet and setting the stage for our modern diet of grains, grasses, and meat and dairy from grazing animals.
In four new studies of carbon isotopes in fossilized tooth enamel from scores of human ancestors and baboons in Africa from 4 million to 10,000 years ago, a team of two dozen researchers found a surprise increase in the consumption of grasses and sedges -- plants that resemble grasses and rushes but have stems and triangular cross sections.
"At last, we have a look at 4 million years of the dietary evolution of humans and their ancestors," says University of Utah geochemist Thure Cerling, principal author of two of the four new studies published online June 3 by the journalProceedings of the National Academy of Sciences. Most funding was from the National Science Foundation.
"For a long time, primates stuck by the old restaurants -- leaves and fruits -- and by 3.5 million years ago, they started exploring new diet possibilities -- tropical grasses and sedges -- that grazing animals discovered a long time before, about 10 million years ago" when African savanna began expanding, Cerling says. "Tropical grasses provided a new set of restaurants. We see an increasing reliance on this new resource by human ancestors that most primates still don't use today."
Grassy savannas and grassy woodlands in East Africa were widespread by 6 million to 7 million years ago. It is a major question why human ancestors didn't seriously start exploiting savanna grasses until less than 4 million years ago.
The isotope method cannot distinguish what parts of grasses and sedges human ancestors ate -- leaves, stems, seeds and-or underground storage organs such as roots or rhizomes. The method also can't determine when human ancestors began getting much of their grass by eating grass-eating insects or meat from grazing animals. Direct evidence of human ancestors scavenging meat doesn't appear until 2.5 million years ago, and definitive evidence of hunting dates to only about 500,000 years ago.
With the new findings, "we know much better what they were eating, but mystery does remain," says Cerling, a distinguished professor of geology and geophysics, and biology. "We don't know exactly what they ate. We don't know if they were pure herbivores or carnivores, if they were eating fish [which leave a tooth signal that looks like grass-eating], if they were eating insects or if they were eating mixes of all of these."
Why Our Ancestor's Diets Matter
The earliest human ancestor to consume substantial amounts of grassy foods from dry, more open savannas "may signal a major and ecological and adaptive divergence from the last common ancestor we shared with African great apes, which occupy closed, wooded habitats," writes University of South Florida geologist Jonathan Wynn, chief author of one of the new studies and a former University of Utah master's student.
"Diet has long been implicated as a driving force in human evolution," says Matt Sponheimer, a University of Colorado, Boulder anthropologist, former University of Utah postdoctoral fellow and lead author of the fourth study................
WALKING TALL ON THE AFRICAN SAVANNAH MAY BE CHOICE RATHER THAN NECESSITY
Evolutionary theories regarding development of our earliest ancestors from tree dwelling quadrupeds to upright bipeds capable of walking and scrambling have been challenged by a new study at the University of York.
Why did humans walk upright? This is one of the fundamental discussions regarding our evolutionary development and previous models were based on adaptations to forest or savannah. This new research examines a process that favoured a series of physical incentives presented by steep rugged terrain similar to that presented by Romano’s (2006) hypothesis of uphill clambering carrying moderately heavy weights as a selective pressure on the development of hominin bipedality, which also focuses on topography as a key variable.
The kind varied landscape shaped during the Pliocene epoch by volcanoes and shifting tectonic plates remains complicated and presents an option to present what is called “Scrambler man” who pursued prey up hill and down gullies and in so doing became that agile, sprinting, enduring, grasping, jumping two-legged athlete that we know today.
Hominins, our early forebears, would have been attracted to the terrain of rocky outcrops and gorges because it offered shelter and opportunities to trap prey. But it also required more upright scrambling and climbing gaits, prompting the emergence of bipedalism.
Challenges to traditional views
The York research challenges traditional hypotheses which suggest our early forebears were forced out of the trees and onto two feet when climate change reduced tree cover.
The study, ‘Complex Topography and Human Evolution: the Missing Link’, was developed in conjunction with researchers from the Institut de Physique du Globe in Paris. It is published in the journal Antiquity.
Dr Isabelle Winder, from the Department of Archaeology at York and one of the paper’s authors, said:
“Our research shows that bipedalism may have developed as a response to the terrain, rather than a response to climatically-driven vegetation changes.
“The broken, disrupted terrain offered benefits for hominins in terms of security and food, but it also proved a motivation to improve their locomotor skills by climbing, balancing, scrambling and moving swiftly over broken ground – types of movement encouraging a more upright gait.”
The research suggests that the hands and arms of upright hominins were then left free to develop increased manual dexterity and tool use, supporting a further key stage in the evolutionary story.
The development of running adaptations to the skeleton and foot may have resulted from later excursions onto the surrounding flat plains in search of prey and new home ranges.
Varied terrain analysis
Dr Winder added “The varied terrain may also have contributed to improved cognitive skills such as navigation and communication abilities, accounting for the continued evolution of our brains and social functions such as co-operation and team work. Our hypothesis offers a new, viable alternative to traditional vegetation or climate change hypotheses. It explains all the key processes in hominin evolution and offers a more convincing scenario than traditional hypotheses.”
Clearly, one of the most important requirements in testing the above hypotheses is the ability to reconstruct ancient physical landscapes. These reconstructions face formidable issues: the degree and complexity of geological change that has occurred on Plio-Pleistocene time scales in actively tectonic and volcanic regions such as the East African Rift.
Extrapolating from present-day conditions to the ancient topography, and the emphasis on searching for locations that are most likely to expose new and early discoveries of human fossils, has caused a bias towards a restricted spatial perspective. Only by field testing will these ideas expand through more detailed investigation of fossil and archaeological sites in their wider landscape setting and will offer a realistic possibility of strengthening the theoretical aspect of the work. This will form an essential element in future research agendas if we are to understand the role of environmental,ecological and climatic changes in human evolution.
Apes like the chimpanzee spend a lot of their time in trees, so their flexible feet are essential to grip branches and allow them to move around quickly - but how most of us ended up with more rigid feet remains unclear.
Jeremy DeSilva from Boston University and a colleague asked the museum visitors to walk barefoot and observed how they walked by using a mechanised carpet that was able to analyse several components of the foot.
Floppy foot
Most of us have very rigid feet, helpful for stability, with stiff ligaments holding the bones in the foot together.
When primates lift their heels off the ground, however, they have a floppy foot with nothing holding their bones together.
This is known as a midtarsal break and is similar to what the Boston team identified in some of their participants.
This makes the middle part of the foot bend more easily as the subject pushes off to propel themselves on to their next step.
Dr DeSilva told BBC News how we might be able to observe whether we have this flexibility: "The best way to see this is if you're walking on the beach and leaving footprints, the middle portion of your footprint would have a big ridge that might show your foot is actually folding in that area."
Here A. sediba is compared with a modern human (L) and a chimp (R)
Another way, he added, was to set up a video camera and record yourself walking, to observe the bones responsible for this folding motion.
Most with this flexibility did not realise they had it and there was no observable difference in the speed of their stride.
In addition, Dr DeSilva found that people with a flexible fold in their feet also roll to the inside of their foot as they walk.
The bone structure of a two-million-year old fossil human relative,Australopithecus sediba, suggests it also had this mobility.
"We are using variation in humans today as a model for understanding what this human creature two million years ago was doing," added Prof De Silva.
Tracy Kivell, a palaeoanthropologist from the Max Planck Institute for Evolutionary Anthropology, said: "The research has implications for how we interpret the fossil record and the evolution of these features.
"It's good to understand the normal variation among humans before we go figure out what it means in the fossil record," Dr Kivell told BBC News.
Artefacts from the African Middle Stone Age (MSA; ∼200 to ∼50 ka), provide us with the first glimpses of modern human art and culture. Approximately 50 ka, one or more subgroups of modern humans expanded from Africa to populate the rest of the world.
Significant behavioural change accompanied this expansion, and archaeologists commonly seek its roots during this period. Recognizable art objects and “jewellery” become common only in sites that postdate the MSA in Africa and Eurasia, but some MSA sites contain possible precursors, including abstractly incised fragments of ochre and perforated mollusc shells interpreted as beads.
Was population growth the driver of change?
Researchers had previously theorised that it was an increase in population that drove behavioural innovations which in turn led to the creation of these artefacts and eventually, the expansion out of Africa. However, by examining mollusc shells from Stone Age sites, Richard Klein of Stanford University and Teresa Steele of University of California, Davis, have determined that a significant population increase did not occur until the Later Stone Age (LSA), after the out of Africa migration had already begun. Their research appears in the June 2013 edition of the Proceedings of the National Academy of Sciences.
Archaeologists have found precursors of modern human artwork and jewellery, including fragments of ochre with abstract incisions and shells with perforations, in MSA sites and it is therefore concluded that the humans who made them, between 85,000 and 65,000 years ago, must have had modern cognitive abilities and behaviours. During the LSA, these abilities and behaviours allowed humans to create objects as recognizable art and spurred the migration to Eurasia.
Population growth has been the popular explanation for the innovations of the MSA. As population increases, the opportunity for innovation increases, while concurrently, the probability that an idea will be lost decreases.
Symbolic thought in the form of decorative art appears in excavations at Blombos Cave on the southern Cape coast from about 75 ka, associated with small perforated shells that retain traces of red ochre. This suggests that they had been collected and strung together as a necklace. In the underlying level dated to about 80 ka, two pieces of ochre were found, engraved with a pattern of lines that formed diamond shapes. The question to be asked is how and when this transformation to modern human behaviour began..............
Neandertals Shared Speech and Language With Modern Humans, Study Suggests
Fast-accumulating data seem to indicate that our close cousins, the Neandertals, were much more similar to us than imagined even a decade ago. But did they have anything like modern speech and language? And if so, what are the implications for understanding present-day linguistic diversity? The MPI for Psycholinguistics researchers Dan Dediu and Stephen C. Levinson argue in their paper in Frontiers in Language Sciences that modern language and speech can be traced back to the last common ancestor we shared with the Neandertals roughly half a million years ago.
The Neandertals have fascinated both the academic world and the general public ever since their discovery almost 200 years ago. Initially thought to be subhuman brutes incapable of anything but the most primitive of grunts, they were a successful form of humanity inhabiting vast swathes of western Eurasia for several hundreds of thousands of years, during harsh ages and milder interglacial periods. We knew that they were our closest cousins, sharing a common ancestor with us around half a million years ago (probably Homo heidelbergensis), but it was unclear what their cognitive capacities were like, or why modern humans succeeded in replacing them after thousands of years of cohabitation. Recently, due to new palaeoanthropological and archaeological discoveries and the reassessment of older data, but especially to the availability of ancient DNA, we have started to realize that their fate was much more intertwined with ours and that, far from being slow brutes, their cognitive capacities and culture were comparable to ours.
Dediu and Levinson review all these strands of literature and argue that essentially modern language and speech are an ancient feature of our lineage dating back at least to the most recent ancestor we shared with the Neandertals and the Denisovans (another form of humanity known mostly from their genome). Their interpretation of the intrinsically ambiguous and scant evidence goes against the scenario usually assumed by most language scientists, namely that of a sudden and recent emergence of modernity, presumably due to a single -- or very few -- genetic mutations. This pushes back the origins of modern language by a factor of 10 from the often-cited 50 or so thousand years, to around a million years ago -- somewhere between the origins of our genus, Homo, some 1.8 million years ago, and the emergence of Homo heidelbergensis. This reassessment of the evidence goes against a saltationist scenario where a single catastrophic mutation in a single individual would suddenly give rise to language, and suggests that a gradual accumulation of biological and cultural innovations is much more plausible.
Interestingly, given that we know from the archaeological record and recent genetic data that the modern humans spreading out of Africa interacted both genetically and culturally with the Neandertals and Denisovans, then just as our bodies carry around some of their genes, maybe our languages preserve traces of their languages too. This would mean that at least some of the observed linguistic diversity is due to these ancient encounters, an idea testable by comparing the structural properties of the African and non-African languages, and by detailed computer simulations of language spread.
One More Homo Species? 3D-Comparative Analysis Confirms Status of Homo Floresiensis as Fossil Human Species
The Liang Bua 1 (LB1) cranium, shown in right side view.
Ever since the discovery of the remains in 2003, scientists have been debating whether Homo floresiensis represents a distinct Homo species, possibly originating from a dwarfed island Homo erectus population, or a pathological modern human. The small size of its brain has been argued to result from a number of diseases, most importantly from the condition known as microcephaly.
Based on the analysis of 3-D landmark data from skull surfaces, scientists from Stony Brook University New York, the Senckenberg Center for Human Evolution and Palaeoenvironment, Eberhard-Karls Universität Tübingen, and the University of Minnesota provide compelling support for the hypothesis that Homo floresiensis was a distinct Homo species.
The study, titled "Homo floresiensiscontextualized: a geometric morphometric comparative analysis of fossil and pathological human samples," is published in the July 10 edition of PLOS ONE.
The ancestry of the Homo floresiensis remains is much disputed. The critical questions are: Did it represent an extinct hominin species? Could it be a Homo erectus population, whose small stature was caused by island dwarfism?
Or, did the LB1 skull belong to a modern human with a disorder that resulted in an abnormally small brain and skull? Proposed possible explanations include microcephaly, Laron Syndrome or endemic hypothyroidism ("cretinism").
The scientists applied the powerful methods of 3-D geometric morphometrics to compare the shape of the LB1 cranium (the skull minus the lower jaw) to many fossil humans, as well as a large sample of modern human crania suffering from microcephaly and other pathological conditions. Geometric morphometrics methods use 3D coordinates of cranial surface anatomical landmarks, computer imaging, and statistics to achieve a detailed analysis of shape.
This was the most comprehensive study to date to simultaneously evaluate the two competing hypotheses about the status of Homo floresiensis.
The study found that the LB1 cranium shows greater affinities to the fossil human sample than it does to pathological modern humans. Although some superficial similarities were found between fossil, LB1, and pathological modern human crania, additional features linked LB1exclusively with fossil Homo. The team could therefore refute the hypothesis of pathology.
"Our findings provide the most comprehensive evidence to date linking the Homo floresiensis skull with extinct fossil human species rather than with pathological modern humans. Our study therefore refutes the hypothesis that this specimen represents a modern human with a pathological condition, such as microcephaly," stated the scientists.
Given the long, awful history of violence between groups of people, it’s easy to think that humans are predisposed to war. But a new study of violence in modern hunter-gatherer societies, which may hold clues to prehistoric human life, suggests that warlike behavior is a relatively recent phenomenon.
Sure, humans are violent, the researchers say — but most hunter-gatherer killing results from flared tempers and personal feuds rather than group conflicts.
The findings contradict the notion “that humans have an evolved tendency to form coalitions to kill members of neighboring groups,” wrote anthropologists Douglas Fry and Patrik Soderberg in their July 18 Science paper.
“The vast majority of us assume that war is ancient, that it’s part and parcel of human nature,” said Fry. “These types of perceptions have very strong influences on what goes on in current-day society.”
Fry and Soderberg hope to illuminate an era stretching from roughly 10,000 years ago, when metal tools appear in the archaeological record, to about 2.5 million years ago, when stone tool use became widespread. This period looms in our anthropological self-regard as humanity’s adolescence, an evolutionary crucible that would shape our species.
A few other researchers consider that view unjustifiably dark, a sort of scientific version of original sin. They say collective human violence was an aberration, not a basic feature of life. In this camp is Fry, who in 2007′s Beyond War: The Human Potential for Peace argued that archaeological evidence of prehistoric warfare was often misinterpreted, and modern hunter-gatherer violence exaggerated.
In most foraging societies, said Fry, lethal aggression was infrequent, and in the archaeological record violence didn’t take regular group-on-group character until relatively recently, when people settled down in ever-larger, more complex and hierarchical societies.
In the new paper, Fry and Soderberg looked at ethnographic histories of 21 nomadic forager societies, compiling a database of every well-documented incidence of lethal aggression that could be found in reputable accounts spanning the last two centuries.
They counted 148 incidents in all, of which more than half involved a single person killing another. Only 22 percent involved multiple aggressors and multiple victims, and only one-third involved conflicts between groups.
Most killings were motivated by sexual jealousy, revenge for a previous murder, insults or other interpersonal quarrels. Collective, between-group violence was the exception, not the rule. To Fry, the weight of evidence suggests that humanity’s origins were, if not exactly peaceful, then not warlike, either.
“When you look at these foraging groups, you see a great deal of cooperation. There are homicides on occasion, but generally people get along very well,” said Fry. “Humans have a capacity for warfare — nobody’s denying that. But to make it a central part of human nature is grossly out of contact with the data.”
Fry’s take on the history of conflict has prompted some conflict itself. Sam Bowles, a Santa Fe Institute economist and behavioral theorist who posits that human cooperative tendencies were shaped by warfare, said the new work “does not support the broader implications that it claims.”
The new dataset is limited, said Bowles, because it excludes less-nomadic, pastoral societies — and even if warfare wasn’t ubiquitous, modest levels would suffice to shape our social evolution, he said.
Anthropologist Richard Wrangham of Harvard University, who has studied chimpanzee conflicts, wasn’t concerned by the pastoralist omission, but said that accounts from modern hunter-gatherers are not reliable guides to the past.
These societies are now scattered, often living beside other, more powerful agricultural societies, said Wrangham. In the past, living along other foraging societies, with less imbalance of power, they’d have been more warlike.
Fry agreed that modern foragers are imperfect windows into humanity’s origins, but said the data do suggest a trend that fits with a paucity of archaeological evidence of warfare from before 10,000 years ago, when complex, settled societies arose.
Anthropologist George Chaplin of Penn State University, who hasn’t been as directly involved in the debate, agrees that “the earliest human ancestors must have been more peaceable than a chimpanzee model would predict.”
Chaplin, who recently wrote about the emergence of group conflict in eastern North America — which appears to have been fueled by increasing human populations and the advent of bows — said the key to peaceability is in large foraging areas and low population densities.
Given the difficulty of reconstructing early history, the debate over warfare and human nature might not ever be settled. But the simple possibility that humans are not innately warlike has immediate implications, said Fry.
Assumptions like these shape the questions that researchers ask. “There’s so much discussion of killing and raiding,” he said, which inadvertently downplays other aspects of forager life, such as the conflict mediation mechanisms that every early society had.
“Perhaps the main selection pressure was on not killing,” said Fry. And in explaining war, we might not look to human nature so much as human environments, social structures and technologies. Perhaps the tendency to war is not in our biology, but our sociology.
“These types of questions about the nature of humanity, about the nature of society, are really relevant today,” said Fry. “People have said to me, ‘We’ve always had war. We always will have war.’” Perhaps, he says, it isn’t necessarily so.
When a single genetic mutation first let ancient Europeans drink milk, it set the stage for a continental upheaval.
In the 1970s, archaeologist Peter Bogucki was excavating a Stone Age site in the fertile plains of central Poland when he came across an assortment of odd artefacts. The people who had lived there around 7,000 years ago were among central Europe's first farmers, and they had left behind fragments of pottery dotted with tiny holes. It looked as though the coarse red clay had been baked while pierced with pieces of straw.
Looking back through the archaeological literature, Bogucki found other examples of ancient perforated pottery. “They were so unusual — people would almost always include them in publications,” says Bogucki, now at Princeton University in New Jersey. He had seen something similar at a friend's house that was used for straining cheese, so he speculated that the pottery might be connected with cheese-making. But he had no way to test his idea.
The mystery potsherds sat in storage until 2011, when Mélanie Roffet-Salque pulled them out and analysed fatty residues preserved in the clay. Roffet-Salque, a geochemist at the University of Bristol, UK, found signatures of abundant milk fats — evidence that the early farmers had used the pottery as sieves to separate fatty milk solids from liquid whey. That makes the Polish relics the oldest known evidence of cheese-making in the world1.
Roffet-Salque's sleuthing is part of a wave of discoveries about the history of milk in Europe. Many of them have come from a €3.3-million (US$4.4-million) project that started in 2009 and has involved archaeologists, chemists and geneticists. The findings from this group illuminate the profound ways that dairy products have shaped human settlement on the continent.
During the most recent ice age, milk was essentially a toxin to adults because — unlike children — they could not produce the lactase enzyme required to break down lactose, the main sugar in milk. But as farming started to replace hunting and gathering in the Middle East around 11,000 years ago, cattle herders learned how to reduce lactose in dairy products to tolerable levels by fermenting milk to make cheese or yogurt. Several thousand years later, a genetic mutation spread through Europe that gave people the ability to produce lactase — and drink milk — throughout their lives. That adaptation opened up a rich new source of nutrition that could have sustained communities when harvests failed.
This two-step milk revolution may have been a prime factor in allowing bands of farmers and herders from the south to sweep through Europe and displace the hunter-gatherer cultures that had lived there for millennia. “They spread really rapidly into northern Europe from an archaeological point of view,” says Mark Thomas, a population geneticist at University College London. That wave of emigration left an enduring imprint on Europe, where, unlike in many regions of the world, most people can now tolerate milk. “It could be that a large proportion of Europeans are descended from the first lactase-persistent dairy farmers in Europe,” says Thomas.
Strong stomachs
Young children almost universally produce lactase and can digest the lactose in their mother's milk. But as they mature, most switch off the lactase gene. Only 35% of the human population can digest lactose beyond the age of about seven or eight (ref. 2). “If you're lactose intolerant and you drink half a pint of milk, you're going to be really ill. Explosive diarrhoea — dysentery essentially,” says Oliver Craig, an archaeologist at the University of York, UK. “I'm not saying it's lethal, but it's quite unpleasant.”............
Neandertals Made the First Specialized Bone Tools in Europe
Four views of the most complete lissoir found during excavations at the Neandertal site of Abri Peyrony.
Modern humans replaced Neandertals in Europe about 40,000 years ago, but the Neandertals' capabilities are still greatly debated. Some argue that before they were replaced, Neandertals had cultural capabilities similar to modern humans, while others argue that these similarities only appear once modern humans came into contact with Neandertals.
"For now the bone tools from these two sites are one of the better pieces of evidence we have for Neandertals developing on their own a technology previously associated only with modern humans," explains Dr. Shannon McPherron of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. He and Dr. Michel Lenoir of the University of Bordeaux have been excavating the site of Abri Peyrony where three of the bones were found.
"If Neandertals developed this type of bone tool on their own, it is possible that modern humans then acquired this technology from Neandertals. Modern humans seem to have entered Europe with pointed bone-tools only, and soon after started to make lissoir. This is the first possible evidence for transmission from Neandertals to our direct ancestors," says Dr. Soressi of Leiden University, Netherland. She and her team found the first of four bone-tools during her excavation at the classic Neandertal site of Pech-de-l'Azé I.
However, we cannot eliminate the possibility that these tools instead indicate that modern humans entered Europe and started impacting Neandertal behavior earlier than we can currently demonstrate. Resolving this problem will require sites in central Europe with better bone preservation.
How widespread this new Neandertal behavior was is a question that remains. The first three found were fragments less than a few centimeters long and might not have been recognized without experience working with later period bone tools. It is not something normally looked for in this time period. "However, when you put these small fragments together and compare them with finds from later sites, the pattern in them is clear," comments Dr. McPherron. "Then last summer we found a larger, more complete tool that is unmistakably a lissoir like those we find in later, modern human sites or even in leather workshops today."
Microwear analysis conducted by Dr. Yolaine Maigrot of the CNRS on of one of the bone tools shows traces compatible with use on soft material like hide. Modern leather workers still use similar tools today. "Lissoirs like these are a great tool for working leather, so much so that 50 thousand years after Neandertals made these, I was able to purchase a new one on the Internet from a site selling tools for traditional crafts," says Dr. Soressi. "It shows that this tool was so efficient that it had been maintained through time with almost no change. It might be one or perhaps even the only heritage from Neandertal times that our society is still using today."
These are not the first Neandertal bone tools, but up to now their bone tools looked like stone tools and were made with stone knapping percussive techniques. "Neandertals sometimes made scrapers, notched tools and even handaxes from bone. They also used bone as hammers to resharpen their stone tools," says Dr. McPherron. "But here we have an example of Neandertals taking advantage of the pliability and flexibility of bone to shape it in new ways to do things stone could not do."
The bone tools were found in deposits containing typical Neandertal stone tools and the bones of hunted animals including horses, reindeer, red deer and bison. At both Abri Peyrony and Pech-de-l'Azé I, there is no evidence of later occupations by modern humans that could have contaminated the underlying levels. Both sites have only evidence of Neandertals.
To know the age of the bone tools, Dr. Sahra Talamo of the Max Planck Institute for Evolutionary Anthropology applied radiocarbon dating to bones found near the bone tools themselves. At Pech-de-l'Azé I, Dr. Zenobia Jacobs of the University of Wollongong applied optically stimulated luminescence (OSL) dating to sediments from the layer with the bone tool. The results place the Pech-de-l'Azé I bone tool to approximately 50 thousand years ago. This is well before the best evidence of modern humans in Western Europe, and it is much older than any other examples of sophisticated bone tool technologies.
Modern Humans Were in China Much Earlier Than Previously Thought
The ongoing debate about when and how anatomically modern humans ("AMH") made their presence ineast Asiahas taken another turn with new evidence recovered from a cave in central China. The finds may push back thegenerally acceptedtime of their appearance in the region by as much as 50,000 years.
A team of six researchers from four institutions, using high-precision mass spectrometric U-series datingtechniques, were able to determine a reliable and constrained date range of between 81 and 101 ka (thousand years) for seven human fossil teeth recovered from the Huanglong Cave in the Hubei Province of central China. The teeth, determined to exhibit anatomically modern human characteristics, were revealed in a layer associated with stone tools and other fossilized animal remains during excavations conducted in 2004, 2005 and 2006 by a joint team from the Hubei Provincial Institute of Cultural Relics and Archaeology and the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences. The excavations were followed by further fieldwork in 2010 and 2011.
Reports Guangun Shen, et al., "the existence of localized thin flowstone formations bracketing the hominin [ancient human] fossil-bearing deposits enables us to firmly constrain the human teeth into the range between 81 ka and 101 ka, probably the most narrow time span for any hominin fossil beyond 45 ka in China".* Flowstones are sheetlike deposits of calcite formed over many thousands of years, the result of water flowing down the walls or along the floors of caves. They are a type of speleothem, or secondary mineral deposit such as a stalagtite or stalagmite, often found in ancient cave systems.
According to the study authors, the finding comes after a series of other relatively recent excavations and reports that have produced "a growing body of evidence for the possible presence of AMH in eastern Asia as early as 100 ka ago".* They refer here to some limestone caves in southern China where scientists have come up with more ancient dates, including Liujiang (between 111 and 139 ka), Ganqian (between 94 and 220 ka), Bailiandong (more than 160 ka), and Zhirendong (more than 100 ka) in Guangxi. The Guanglong Cave results, however, are considered the most reliable because of the much narrower constraining range of 81 to 101 ka as determined by the latest U-series datingtechnology.
These new findings have challenged the prevailing theory among scientists that anatomically modern humans were not present in China or east Asia until roughly around 40,000 - 50,000 years ago. This is based on earlier findings at a number of sites across China and east Asia that point to a ‘gap’ between 100 ka and 40 ka ago lacking any human fossils, more specifically between the latest archaic humans and the earliest modern humans, and genetic studies of present-day Chinese populations that have suggested a late appearance of AMH in eastern Asia.
But this previous data, maintains Shen, et al., was generated using older, less reliable datingtechniques and excluded fossils claimed to represent AMH. "Based on our work on the sites of H. erectus (an earlier form of human) and of both archaic and modern H. sapiens over the past twenty plus years, we argue that the temporal framework in China has been artificially ‘compressed and gapped,’meaning that due to limitations in previous dating techniques and practices, the ages of Chinese hominin fossils have been significantly postdated (compressed), and that a temporal gap between archaic H. sapiens and AMH has been artificially created (gapped)."*
Regarding the genetic studies, they argue that "more solid skeletal discoveries, along with parallel studies in relevant disciplines are needed to reconcile the geochronology and the molecular clock."*
Perhaps even more significant, the researchers suggest that the entire timeline for hominin (ancient human) presence in east China should be shifted back earlier in time and should be continuous (without the gap), based on updated research. This includes the advent of H. erectus at more than 400 ka old, rather than the current 230 ka; archaic H. sapiens at more than 200 ka, instead of ca. 110 ka; and the emergence of AMH at around 100 ka or earlier.
Concludes the team: "The newly established timeline for hominin fossils in China, as a result of more meticulous stratigraphic work and the advancement in dating techniques, demands a reexamination of hominin fossils and associated materials in a more coherent chronological context in China."*
Details of the study have been published in the August 2013 issue of the Journal of Human Evolution as Mass spectrometric U-series dating of Huanglong Cave in Hubei Province, central China: Evidence for early presence of modern humans in eastern Asia.
Anthropologists confirm link between cranial anatomy and two-legged walking
Comparison of the skeletons of three bipedal mammals: an Egyptian jerboa, an eastern gray kangaroo and a human.
Anthropology researchers from The University of Texas at Austin have confirmed a direct link between upright two-legged (bipedal) walking and the position of the foramen magnum, a hole in the base of the skull that transmits the spinal cord.
The study, published in a forthcoming issue of the Journal of Human Evolution, confirms a controversial finding made by anatomist Raymond Dart, who discovered the first known two-legged walking (bipedal) human ancestor, Australopithecus africanus. Since Dart's discovery in 1925, physical anthropologists have continued to debate whether this feature of the cranial base can serve as a direct link to bipedal fossil species.
Chris Kirk, associate professor of anthropology and co-author of the study, says the findings validate foramen magnum position as a diagnostic tool for fossil research and sheds further insight into human evolution.
"Now that we know that a forward-shifted foramen magnum is characteristic of bipedal mammals generally, we can be more confident that fossil species showing this feature were also habitual bipeds," Kirk says. "Our methods can be applied to fossil material belonging to some of the earliest potential human ancestors."
The foramen magnum in humans is centrally positioned under the braincase because the head sits atop the upright spine in bipedal postures. In contrast, the foramen magnum is located further toward the back of the skull in chimpanzees and most other mammals, as the spine is positioned more behind the head in four-legged postures.
As part of the study, the researchers measured the position of the foramen magnum in 71 species from three mammalian groups: marsupials, rodents and primates. By comparing foramen magnum position broadly across mammals, the researchers were able to rule out other potential explanations for a forward-shifted foramen magnum, such as differences in brain size.
According to the findings, a foramen magnum positioned toward the base of the skull is found not only in humans, but in other habitually bipedal mammals as well. Kangaroos, kangaroo rats and jerboas all have a more forward-shifted foramen magnum compared with their quadrupedal (four-legged walking) close relatives.
These particular mammals evolved bipedal locomotion and anteriorly positioned foramina magna independently, or as a result of convergent evolution, says Gabrielle Russo, who is a postdoctoral research fellow at Northeast Ohio Medical University and lead researcher of the study.
"As one of the few cranial features directly linked to locomotion, the position of the foramen magnum is an important feature for the study of human evolution," Russo says. "This is the case for early hominin species such as Sahelanthropus tchadensis, which shows a forward shift of the foramen magnum but has aroused some controversy as to whether it is more closely related to humans or African apes."
Hmm, wonder if anyone has thought to check out skeletons of T Rex or Velociraptor, both were essentially bipedal.
"Arguing with someone who hates you or your ideas, is like playing chess with a pigeon. No matter what move you make, your opponent will walk all over the board and scramble the pieces".
Unknown.
DNA Research Sheds Light On Ancestry of Ashkenazi Jews
Many of the maternal ancestors of modern Ashkenazi Jews were European converts, according to a research project headed by a University of Huddersfield professor.
The young science of archaeogenetics has been used to settle a long-standing controversy -- the origin of Europe's Ashkenazi Jews. Are they principally descended from forbears who migrated from Palestine in the first century AD? Or were their ancestors Europeans who converted to Judaism?
A new article in the leading journalNature Communications claims to have settled the question. Analysis of DNA samples has shown that on the female line, the Ashkenazim are descended not from the Near East but from southern and western Europe.
Professor Martin Richards heads the Archaeogenetics Research Group based at the University of Huddersfield and he is a co-author of the new article, entitled "A substantial prehistoric European ancestry amongst Ashkenazi maternal lineages."
In Hebrew, the word "Ashkenazi" means "Germans" and the term is used for Jews of eastern European origin who historically spoke the Yiddish or Judeo-German language. Professor Richards says that the new explanation for their origins was one of the most significant findings from a wider project in which he and his colleagues -- principally the Portuguese PhD students Marta Costa and Joana Pereira -- were analysing mitochondrial DNA samples (i.e. DNA that traces the maternal line) in order to investigate the prehistoric settlement of Europe by migrants from the Near East.
Ashkenazi Jewish lineages were among the large quantity of publicly available mitochondrial genomes of people from Europe, the Caucasus and the Middle East that entered the analysis. It was discovered that in the vast majority of cases, Ashkenazi lineages are most closely related to those of southern and western Europe and that they had been present in Europe for many thousands of years.
"This suggests that, even though Jewish men may indeed have migrated into Europe from Palestine around 2000 years ago, they seem to have married European women," states Professor Richards.
This seems to have happened first along the Mediterranean, especially in Italy, and later -- but probably to a lesser extent -- in western and central Europe. This suggests that, in the early years of the Diaspora, Judaism took in many converts from amongst the European population, but they were mainly recruited from amongst women. Thus, on the female line of descent, the Ashkenazim primarily trace their ancestry neither to Palestine nor to Khazaria in the North Caucasus -- as has also been suggested -- but to southern and western Europe.
"The origins of the Ashkenazim is one of the big questions that people have pursued again and again and never really come to a conclusive view," said Prof Richards, who has described the new data as "compelling."
A team of scientists are now suggesting that the Denisovans, an ancient human species that lived concurrent with Neanderthals and early modern humans, may have successfully crossed Wallaces Line, one of the world's largest biogeographic marine barriers in Indonesia, subsequently interbreeding with early modern humans who were on their way to Australia and New Guinea.
In 2010, a small bone fragment of a finger bone was discovered in Denisova cave in the Altai Mountains of Asia. Later genetic analysis indicated that it belonged to a heretofore unknown ancient human species, named Denisovans, and that their DNA is still present in native populations of Australia, New Guinea and surrounding regions. There is a distinct, and puzzling, absence of the DNA in Asian populations.
Now, as published in a Science opinion article, Alan Cooper of the University of Adelaide in Australia and Chris Stringer of the Natural History Museum in the UK are suggesting that the DNA presence could be the result of the Denisovans crossing over the deep oceanic marine barrier of Wallaces Line, a biogeographic gap that is so significant that it defines the division between European and Asian mammals on its west and marsupial-dominated Australasia on its east.
"In mainland Asia, neither ancient human specimens, nor geographically isolated modern indigenous populations have Denisovan DNA of any note, indicating that there has never been a genetic signal of Denisovan interbreeding in the area," says Professor Cooper, Director of the University of Adelaide's Australian Centre for Ancient DNA. "The only place where such a genetic signal exists appears to be in areas east of Wallace's Line and that is where we think interbreeding took place -- even though it means that the Denisovans must have somehow made that marine crossing."
"The conclusions we've drawn are very important for our knowledge of early human evolution and culture," says Stringer. "Knowing that the Denisovans spread beyond this significant sea barrier opens up all sorts of questions about the behaviours and capabilities of this group, and how far they could have spread."
"The key questions now are where and when the ancestors of current humans, who were on their way to colonise New Guinea and Australia around 50,000 years ago, met and interacted with the Denisovans," says Professor Cooper.
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