• We have updated the guidelines regarding posting political content: please see the stickied thread on Website Issues.

Modern Human Origins

Homo missing linkus? Gawis cranium

Source
Could Ethiopian skull be missing link?
Scientists believe find could link homo erectus and modern man

ADDIS ABABA, Ethiopia (AP) -- Scientists in northeastern Ethiopia said Saturday that they have discovered the skull of a small human ancestor that could be a missing link between the extinct Homo erectus and modern man.

The hominid cranium -- found in two pieces and believed to be between 250,000 and 500,000 years old -- "comes from a very significant period and is very close to the appearance of the anatomically modern human," said Sileshi Semaw, director of the Gona Paleoanthropological Research Project in Ethiopia.

Archaeologists found the early human cranium five weeks ago at Gawis in Ethiopia's northeastern Afar region, Sileshi said.

Sileshi, an Ethiopian paleoanthropologist based at Indiana University, said most fossil hominids are found in pieces but the near-complete skull -- a rare find -- provided a wealth of information.

"The Gawis cranium provides us with the opportunity to look at the face of one of our ancestors," the archaeology project said in a statement. "Additionally, this fossil links us with the past by showing a face that is recognizably different and more primitive than ours."

Homo erectus, which many believe was an ancestor of modern Homo sapiens, is thought to have died out 100,000 to 200,000 years ago.

The cranium dates to a time about which little is known -- the transition from African Homo erectus to modern humans. The fossil record from Africa for this period is sparse and most of the specimens poorly dated, project archaeologists said.

The face and cranium of the fossil are recognizably different from that of modern humans, but it bears unmistakable anatomical evidence that it belongs to the modern human's ancestry, Sileshi said.

"The form of the face and the brain are among the best means for exploring the evolutionary path of humans, and the Gawis cranium preserves both areas," according to the statement.
8)
 
More
Scientists find early human cranium in Ethiopia
By DPA
Mar 24, 2006, 19:00 GMT

Addis Ababa - Ethiopian and US scientists engaged in palaeo- anthropological field research announced Friday the discovery of a human cranium in Gona, in Ethiopia's north-eastern Afar region.

The 'significantly complete cranium' was believed to have stemmed from the Middle Pleistocene stage, making it 200,000 to 500,000 years old, said Dr Sileshi Semaw, director of the Gona Project.

The find consisted of a new hominid fossil. Semaw, who is based at CRAFT Stone Age Institute of Indiana University in the United States, said the discovery in Gawis near Gona, 'appears to be intermediate between earlier Homo erectus and later Homo sapiens and may be sampling a single lineage.'

'I'm thrilled to have a complete cranium discovered from Gona that can provide key information for understanding the variation that existed during the Middle Pleistocene period,' Semaw said.

The cranium was found on February 16 by Asahmed Humet, an Afari pastoralist working with the project scientists on archaeological reconnaissance survey.

'The Gawis cranium comes from a time of transition to modern humans from African Homo erectus that is poorly known. The fossil record from Africa for this period is sparse and most of the specimens are poorly dated,' he said.

Semaw, who is attached to the state Authority for Research and Conservation of Cultural Heritage in Addis Ababa, told reporters that the Gona Project area has sediments spanning the last 5.6 million years.

Significant archaeological collections of Late Acheulean stone tool-making tradition and numerous fossil animals were found in the area, 'opening a widow into intriguing and important period in the development of modern humans.'

The Gona archaeological sites are known for the discovery of the oldest excavated stone tools in the world dating back 2.6 million years. Early in 2005, members of the Gona Project also announced the discovery of hominids assigned to Ardipithecus ramidus, among the earliest hominid genus in Africa dating between 4.3 million to 4.5 million years ago.
 
Neanderthal 'butcher shop' found in France

French and Belgian archaeologists say they have proof Neanderthals lived in near-tropical conditions near France's Channel coast about 125,000 years ago.

In a dig at Caours, near Abbeville, France, archeologists found evidence of a Neanderthal "butcher's shop" to which animals as large as rhinoceros, elephant and aurochs, the forerunner of the cow, were dragged and butchered, The Independent reported Wednesday.

Jean-Luc Locht, a Belgian expert in prehistory at the French government's archaeological service, told the newspaper: "This is a very important site, a unique site. It proves Neanderthals thrived in a warm northwest Europe and hunted animals like the rhinoceros and the aurochs, just as they previously, and later, hunted ice-age species like the mammoth and the reindeer."

Scientists said the animal bones showed signs of having been sawn, crushed or stripped of their meat by flint tools.

Patrick Auguste, an expert on archaeozoology at the French Center for National Scientific Research said: "You have to wonder at the artistry, the exceptional skill, with which the flint tools have been shaped. The Neanderthals may have had thicker fingers than us but they were certainly not clumsy."

http://www.physorg.com/printnews.php?newsid=78597836
 
Double Cropping the Earliest Agriculture
By Michael Balter
ScienceNOW Daily News
13 February 2007

A new study suggests that barley may have undergone domestication twice, a finding with important implications for understanding the spread of farming.
Archaeologists have long debated whether the so-called founder crops of the agricultural revolution--including wheat and barley--were domesticated once or multiple times. The record is ambiguous. Over the past decades, they have unearthed the earliest remains of domesticated barley at sites in the Fertile Crescent that date back 10,500 years. But there is also evidence for barley cultivation about 9000 years ago at sites further east in Central Asia. Today, the wild progenitors of domesticated wheat and other founder crops grow only in the Fertile Crescent, but wild barley is found in the western and eastern regions. As a result, archaeologists haven't been sure whether the cultivated barley in the east came from the Fertile Crescent or was domesticated directly from local wild plants.

To find out, evolutionary biologists Peter Morrell and Michael Clegg of the University of California, Irvine, sequenced genes of wild and domesticated barley from the two regions. They focused on seven genes that differ slightly according to the plants' geographic origins. The genetic variations in the eastern domesticated samples much more closely resembled those in the wild plants from the east than those in wild plants from the Fertile Crescent, they report online this week in the Proceedings of the National Academy of Sciences. Morrell and Clegg conclude that barley was domesticated at least twice, first in the Fertile Crescent and then between 1500 to 3000 kilometers further east in Central Asia.

Archaeobotanist George Willcox of the National Center for Scientific Research in Lyons, France, says that the paper demonstrates that the origins of agriculture "are far more complex than the simplistic view of a single event." Willcox adds that there might have been more than two domestications of barley and other crops, but that the evidence for them has been lost: "Archaeology tells us that sites were abandoned, cultures came to a dead end, and with them their crops."

http://sciencenow.sciencemag.org/cgi/co ... 2007/213/2
 
160,000-Year-Old Child Suggests Modern Humans Got Early Start
Kelly Hearn
for National Geographic News

March 14, 2007
Bucking conventional wisdom, a new study says early members of our species, Homo sapiens, may have known what it was like to be a kid.

A long childhood is considered one of things that separate so-called modern humans from the first Homo sapiens and older human species, such as Homo erectus.



A Study With Teeth

European researchers used x-ray imaging to study the growth patterns of teeth in the juvenile fossil found in Morocco. Similar to tree rings, the patterns are a record of aging.

What they revealed is that this fossil is the earliest known human with a long childhood, according to Tanya Smith, an anthropologist at the Max Planck Institute for Evolutionary Anthropology in Germany.

In the teeth the scientists found signs of modern-human development patterns—that is, relatively long periods of slow development and growth. A prolonged childhood is seen as necessary for the type of learning that leads to culture and complex society.

The juvenile fossil "showed an equivalent degree of tooth development to living [modern] human children at the same age," the report authors write.

According to the researchers, the study challenges theories about when and where humans acquired modern bodies and behaviors.

The findings also may help prove that "modern biological, behavioral, and cultural characteristics" were relative latecomers in the past six million years of human evolution.

(Related: "Adolescence Came Late in Human Evolution, Study Shows" [December 5, 2001].)

"These findings are in contrast to studies that suggest that earlier fossil hominins [humans and our ancestral species] possessed short growth periods, which were more similar to chimpanzees than to living humans," the study authors write in this week's issue of the journal Proceedings of the National Academy of Sciences.

Study co-author Smith said her research team knew that human ancestors living several million years ago grew up differently from modern children.

"What we didn't know was when the modern human condition of a long childhood and slow period of growth and development evolved," she said.



The study suggests that developmentally modern humans existed at least 160,000 years ago, which Smith says is just slightly younger than the earliest fossil Homo sapiens from East Africa.

Promising New Method

"It is a great result that today we can really measure growth rates of teeth due to CT [and] x-ray technology," said Professor Ottmar Kullmer, a paleoanthropologist at the Research Institute Senckenberg in Germany.

"These new possibilities of modern analysis methods augment the understanding of early Homo sapiens development and human evolution in general."

Kullmer, who was not a participant in the study, said that the discovery of a relatively long human childhood about 160,000 years ago points to "a complex social system in early Homo sapiens groups."

"Probably, social behavior was one of the important survival strategies of early humans."

http://news.nationalgeographic.com/news ... umans.html
 
Why Aren't Humans Furry? Stone-Age Moms Could Be The Answer
19 Mar 2007

A prize-winning paper suggests that humans are hairless apes because Stone-Age mothers regarded furry babies as unattractive

Medical Hypotheses, an Elsevier publication, has announced the winner of the 2006 David Horrobin Prize for medical theory. Written by Judith Rich-Harris, author of The Nurture Assumption and No Two Alike, the article, "Parental selection: a third selection process in the evolution of human hairlessness and skin color" was judged to best embody the spirit of the journal. The £1,000 prize, launched in 2004, is awarded annually and named in honour of Dr. David Horrobin, the renowned researcher, biotechnology expert and founder of Medical Hypotheses, who died in 2003.

Harris' paper describes Stone Age societies in which the mother of a newborn had to decide whether she had the resources to nurture her baby. The newborn's appearance probably influenced whether the mother kept or abandoned it. An attractive baby was more likely to be kept and reared.

Harris' theory is that this kind of parental selection may have been an important force in evolution. If Stone Age people believed that hairless babies were more attractive than hairy ones, this could explain why humans are the only apes lacking a coat of fur. Harris suggests that Neanderthals must have been furry in order to survive the Ice Age. Our species would have seen them as "animals" and potential prey. Harris' hypothesis continues that Neanderthals went extinct because human ancestors ate them.

This year's prize judge was Professor Jonathan Rees FMedSci of Edinburgh University, Scotland - co-discoverer of the 'red hair gene'. Professor Rees said: "This paper is an excellent example of the kind of bold thinking and theorizing which David Horrobin intended to encourage when he began Medical Hypotheses. I hope that Judith Rich Harris' idea provokes debate and further investigation of this topic."

###

The full article reference is: Harris JR. Parental selection: a third selection process in the evolution of human hairlessness and skin color.

Medical Hypotheses. 2006; 66: 1053-1059.

About Elsevier

Elsevier is a world-leading publisher of scientific, technical and medical information products and services. Working in partnership with the global science and health communities, Elsevier's 7,000 employees in over 70 offices worldwide publish more than 2,000 journals and 1,900 new books per year, in addition to offering a suite of innovative electronic products, such as ScienceDirect (http://www.sciencedirect.com/), MD Consult (http://www.mdconsult.com/), Scopus (http://www.info.scopus.com/), bibliographic databases, and online reference works.

Elsevier (http://www.elsevier.com/) is a global business headquartered in Amsterdam, The Netherlands and has offices worldwide. Elsevier is part of Reed Elsevier Group plc (http://www.reedelsevier.com/), a world-leading publisher and information provider. Operating in the science and medical, legal, education and business-to-business sectors, Reed Elsevier provides high-quality and flexible information solutions to users, with increasing emphasis on the Internet as a means of delivery. Reed Elsevier's ticker symbols are REN (Euronext Amsterdam), REL (London Stock Exchange), RUK and ENL (New York Stock Exchange).

Contact: Tanya Wheatley
Elsevier


http://www.medicalnewstoday.com/medical ... wsid=65232
 
Asia? Africa? Asia? Africa?

Skeleton holds key to origin of man
By Roger Highfield, Science Editor
Last Updated: 2:24am BST 03/04/2007

A skeleton of a possible hybrid between modern and more ancient humans has been found in China, which challenges the theory that modern man originated in Africa.

Most experts believe that our ancestors emerged in Africa more than 150,000 years ago and then migrated around the world.

However, in the Proceedings of the National Academy of Sciences, Prof Erik Trinkaus and colleagues provide details of a skeleton found in 2003 from Tianyuan Cave near Beijing.

The skeleton is 42,000 to 38,500 years old, making it the oldest modern human skeleton from eastern Eurasia, and one of the oldest modern humans from the region.

Most of its features match those of modern man, though some are more like late archaic humans, including the Neanderthals. The authors conclude that, as our ancestors spread, they interbred with local, more ancient, types of human.

The researchers say it is unlikely that a simple spread of modern humans occurred east of Africa, especially because slightly younger skeletons have been found in eastern Eurasia with similar features.

"The partial skeleton from Tianyuan is an important find, since there is a dearth of material from east Asia to document how modern humans became established there," said Prof Chris Stringer of the Natural History Museum.

"Radiocarbon dates place the find close in age to the earliest Homo sapiens fossils so far discovered in Europe, Lebanon, Malaysia and Australia.

"Outside of Africa, only the early modern finds from Skhul and Qafzeh [in Israel], and possibly Liujiang from southern China, are of much greater antiquity."
http://tinyurl.com/25w88t
 
Ancient human unearthed in China

The remains include a lower jaw as well as leg bones
The remains of one of the earliest modern humans to inhabit eastern Asia have been unearthed in a cave in China.
The find could shed light on how our ancestors colonised the East, a movement that is only poorly understood by anthropologists.

Researchers found 34 bone fragments belonging to a single individual at the Tianyuan Cave, near Beijing.

Details of the discovery appear in Proceedings of the National Academy of Sciences journal.

Radiocarbon dates, obtained directly from the bones, show the person lived between 42,000 and 39,000 years ago.

"For this time period, which is critical for understanding the spread of modern humans around the world, we have two well-dated human fossils from eastern Asia," said co-author Professor Erik Trinkaus, from Washington University in St Louis, US.

"We have remains from the Niah Cave from Sarawak on Borneo, and now this specimen from China. As you go west, the next specimens are from Lebanon. There's nothing in between."

Interbreeding theory

According to the "Out of Africa" theory, modern humans (Homo sapiens) evolved in East Africa and then spread out across the globe about 70,000 years ago, replacing earlier, or archaic, human populations, such as the Neanderthals, with very little, if any, interbreeding.

The Tianyuan remains display diagnostic features of modern H. sapiens. But co-author Erik Trinkaus and his colleagues argue, controversially, that the bones also display features characteristic of earlier human species, such as relatively large front teeth.

The most likely explanation, they argue, is interbreeding between early modern humans emerging from Africa and the archaic populations they encountered in Europe and Asia.

"The pattern we see across the Old World is basically a modern human in terms of its newly emerged characteristics, but also a minority of traits that are absent or lost in the earliest modern humans in East Africa," Professor Trinkaus told the BBC News website.

"The question is where did they get them from? Either they re-evolved them, which is not very likely, or, to some degree, they interbred with archaic groups.

"Sex happens. I find this neither disturbing nor surprising."

He added that evidence from the animal world suggested two closely related species, which have been separate for less than two million years, could interbreed successfully when given the opportunity to mate.

One example from the UK is the Scottish wildcat, which is being absorbed into domestic cat populations through interbreeding.

The domestic cat and the wildcat are distinct species separated by hundreds of thousands, if not millions, of years, and have very different body sizes. Despite this, pairings produce fertile, viable offspring.

Signs of disease

The view of interbreeding between Homo sapiens and archaic humans is controversial. Other palaeoanthropologists say that some of these features are simply retained from ancient African ancestors.

And most genetic evidence gathered from present-day humans does not appear to support significant interbreeding between modern humans from Africa and archaics.

The researchers' analysis of the bones has revealed several interesting details about the Tianyuan individual's lifestyle.

The person's age at death was estimated by how much the teeth had worn down. This put them in their late 40s or 50s.

But the lack of a pelvis among the remains means that it is not possible to say with any certainty what sex the individual was.

The Tianyuan specimen shows several signs of disease. The individual had lost a number of their teeth before death, not unusual considering their age.

The researchers also identified several lesions, or growths, on the leg bones, which appear to have been caused by a condition affecting the muscle attachments around both knees.

Whatever condition these were caused by, however, it does not appear to have disabled the person, because the remainder of the leg bones suggest the person kept active.

The single toe bone which was unearthed seems to suggest the individual wore shoes, pushing back the earliest known evidence for footwear by about 10,000 years.

An earlier study by Professor Trinkaus shows that human small toes became weaker during the stage of prehistory known as the Upper Palaeolithic, and that this can probably be attributed to the adoption of sturdy shoes.

The invention of rugged shoes reduced humans' reliance on strong, flexile toes to grip and balance.


http://news.bbc.co.uk/2/hi/science/nature/6518527.stm
 
It has always amazed me how much misinformation Lloyd can pack into one of his slide shows. Try the one called 'Sumer' for a slice of Sitchin-knows-what-he-is-talking-about type of humor.
 
Stone tools 'change migration story'
http://www.bbc.co.uk/news/science-environment-11327442
By Katie Alcock Science reporter, BBC News, Birmingham

Stone tools (Petraglia et al) Dr Petraglia says robust dates can be put against the tools his group is uncovering

A research team reports new findings of stone age tools that suggest humans came "out of Africa" by land earlier than has been thought.

Geneticists estimate that migration from Africa to South-East Asia and Australia took place as recently as 60,000 years ago.

But Dr Michael Petraglia, of Oxford University, and colleagues say stone artefacts found in the Arabian Peninsula and India point to an exodus starting about 70,000 to 80,000 years ago - and perhaps even earlier.

Petraglia, whose co-workers include Australian and Indian researchers, presented his ideas at the British Science Festival, which is hosted this year at Aston University.

"I believe that multiple populations came out of Africa in the period between 120,000 and 70,000 years ago," he said. "Our evidence is stone tools that we can date."

Most of the tools are from far inland - hundreds of kilometres from the coasts. This means it was more likely humans migrated by land than in boats, he said.

The tools are found in areas that are often very inhospitable now, but which at the time would have been much more conducive to migration.

"During the period we're talking about, the environments were actually very hospitable," he told BBC News. "So where there are deserts today, there used to be lakes and rivers, and there was an abundance of plants and animals."

The team found the stone tools - ranging from a couple of centimetres to nearly 10cm in size - in layers of sediment that they can date using sand and volcanic material found above and below the implements. The tools were mainly either spear heads or scrapers.
Dig site (Petraglia et al) Most dig sites are inland

In particular, some tools were sandwiched in ash from the famous Toba eruption that geologists can date very accurately to 74,000 years ago.

Other species of early humans clearly left Africa before our species (Homo sapiens), but Dr Petraglia's team thinks that the tools it has found are the type made by modern humans - and not those of Neanderthals, for instance.

Previous research has leaned heavily on examining the genetics of different modern populations to find out how long ago they shared a common ancestor - their African common ancestor.

Professor Chris Stringer, of the Natural History Museum in London, said this genetic data showed humans left Africa around 60,000 years ago or even more recently.

He agreed that "these tools show that people were in these regions, but the genetic data show an exit from Africa of later than 60,000 years ago. The people in India could have died out."

Dr Petraglia, however, suggested that researching these migrations using population genetics might not lead to accurate results, because all of the genetic studies were based on today's people.

The absence of ancient DNA to make additional tests made this area of investigation much less reliable, he claimed.

Dr Petraglia's team now hopes to continue its excavations in the region. "We have literally hundreds of projects in Europe and a handful in the Arabian-South Asian belt," he said.
 
Riddle of Aboriginal-type skull found in Brazil

HOW did a skull with features similar to those of an Aboriginal Australian wind up at the bottom of a limestone cave in Brazil, covered with 11,000 years' worth of mud, rocks and gravel?

The solution may rewrite early human history.

The owner of the skull, a female whom Professor Walter Neves, an anthropologist, named Luzia, had eyes and a nose that sat low in the skull.

Her brain case was long and narrow, and a facial reconstruction reveals a projected profile, the chin sitting out further than the forehead.

These are not the features of a South American. Instead they are consistent with the anatomy of sub-Saharan Africans, Aboriginal Australians and some early Pacific Islanders.

For years many scientists have accepted the theory that North America was colonised by a single wave of early humans who travelled from north-east Asia about 11,000 years ago and resembled Native Americans.

The full story was published in the latest issue of the magazine Cosmos. Professor Neves told the writer Jacqui Hayes that Luzia was related to Australian Aborigines through an ancestor from south-east Asia. He believes one group of early humans made their way to Australia about 50,000 years ago, and another travelled through Asia to arrive in Alaska about 15,000 years ago – thousands of years before the Clovis people.

Professor Neves hopes genetic analysis will help settle the question of where Luzia's ancestors came from, Hayes wrote.

However, an anthropologist at the University of Adelaide, Maciej Henneberg, believes the two waves of migration theory might be too simplistic. "I'd rather accept two waves than one wave, but models that assume people can migrate once, or twice, and then never repeat it are denigrating human intelligence."

Professor Henneberg said it was more likely there was a constant flow of people migrating back and forth exchanging genetic material.

I highlighted those bits as this is what I always thought - people just don't move in single waves. It's got to be a constant coming and going - it's always been like that.

http://www.smh.com.au/world/science/rid ... 15zwy.html
 
I saw a documentary on this topic some years ago. The thesis was that the first people to reach the Americas were related to Australian Aboriginals, and that they had been gradually wiped out by the ancestors of the American Indians. Supposedly the survivors had been pushed further and further south until they found themselves on Tierra del Fuego. DNA analysis apparently shows similarities between the Fuegians and indigenous Australians.
 
Did the first humans come out of Middle East?
Modern man may have evolved in the Middle East rather than Africa, it has been claimed, after the discovery of remains said to be more than 400,000 years old.
By Peter Hutchison 8:00AM GMT 28 Dec 2010

Israeli researchers claimed to have found eight human-like teeth in the Qesem cave near Rosh Ha’Ayin, 10 miles from Israel's Ben Gurion airport.

Archaeologists from Tel Aviv University said the teeth were 400,000 years old, from the Middle Pleistocene Age, which would make them the earliest remains of homo sapiens yet discovered in the world.

If true it overturns the belief that homo sapiens, the direct descendant of modern man, evolved in Africa about 200,000 years ago.

According to the “Out of Africa” theory, homo sapiens gradually migrated north, through the Middle East, to Europe and Asia between 70,000 and 50,000 years ago.

But in recent years discoveries in Spain and China have also questioned the theory that man originated in Africa.

The latest findings, published in the American Journal of Physical Anthropology, said the size and shape of the teeth were very similar to those of modern man.

Prof Avi Gopher and Dr Ran Barkai of the Institute of Archaeology at Tel Aviv University also found evidence of the use of fire, hunting, and the cutting and mining of raw materials to produce flint tools, which suggested a sophisticated form of society.

They said further research was needed to solidify their claim but if proven it “changes the whole picture of evolution”.

http://www.telegraph.co.uk/news/worldne ... -East.html
 
The downside of sex with Neanderthals
Some modern humans carry immune genes that originated in Neanderthals and a related species. But these genes may have come at a price

One question seemed to hang in the air more than any other when scientists first turned the powerful techniques of modern genetics on the fragile and damaged remains of ancient humans: did we or didn't we? Have sex with them, that is.

The answer came after years of painstaking work, when material extracted from the leg of a Neanderthal and the fingerbone of a Denisovan, an apparent sister species, yielded readable DNA. It turned out that most of us have some of their genes. The Neanderthals contributed up to 4% of modern Eurasian genomes, while the Denisovans contributed roughly 4-6% of modern Melanesian genomes. That doesn't happen by holding hands.

And so the scene was set. Hundreds of thousands of years ago, early humans in Africa split into several groups, among them Homo sapiens, Neanderthals and their apparent sister species, the Denisovans. The Neanderthals headed for West Asia and Europe, the Denisovans to East Asia. Our ancestors left Africa much later, and arrived in Eurasia where the others had set up home. Cue amorous encounters, and surely a fair amount of less than amorous contact.

But the question of whether our ancestors mated with these other human-like groups was always just the starting point for a line of inquiry. With interbreeding now well-established the intriguing question is, what came of it? How did our ancestors' antics shape the people we are today?

A glimpse of the legacy of those ancient encounters is revealed in a study reported today in the US journal, Science. An international team of scientists, led by Stanford University, scoured the Neanderthal and Denisovan genomes for gene variants that are central to the immune system. These genes belong to a group known as the HLA class I genes, which govern the body's ability to recognise and destroy dangerous pathogens.

By comparing the HLA genes of modern human populations with those from Denisovans and Neanderthals, the scientists identified a handful that could be traced back to ancient sexual encounters between the groups. One variant, known as HLA-B*73, likely arose in modern humans after cross-breeding with Denisovans. The variant is most common in West Asian populations, the region where the mating probably happened.

The Neanderthals contributed a string of HLA gene variants, or alleles, to the modern Eurasian population's gene pool, the study found.

There was good reason for Neanderthal and Denisovan immune system genes to have spread through the populations of modern humans who encountered them. Both Neanderthals and Denisovans had established themselves long before modern humans arrived. Their immune systems had adapted to the threats of the local environment. When those genes crossed into modern humans, they conveyed an advantage. Natural selection took care of the rest.

But the scientists think there was a downside. Inheriting Denisovan or Neanderthal immunity genes will have helped modern humans to fight the diseases of the day, but beyond the age of reproductive maturity they might have a more harmful effect, turning our immune systems on ourselves.

Paul Norman, a co-author on the paper, put it like this: "There's enormous genetic variation in people's immune systems and that can control how different people fight different diseases. This could go some way to explaining why some people are better at fighting some infections than others, but we think it also goes some way to explaining why some people are susceptible to autoimmune diseases."

Autoimmune diseases are conditions that arise when the immune system turns its firepower on the body, usually when it mistakenly identifies the body's tissues as foreign, and so potentially dangerous.

"The vast majority of autoimmune diseases have been shown by genome-wide association studies to be associated with particular HLA alleles and we find a couple of those in Denisovans," Norman added. "So it looks to me like modern humans have acquired these alleles, but we weren't kind of prepared for them, we hadn't grown up with them, and in some circumstances, they can start to attack us as well as the viruses and other pathogens."

The group is now investigating a gene variant called HLA-B51, which came from cross-breeding with Neanderthals and has already been linked to Behcet's disease, a rare and chronic inflammatory condition.

How else might immune genes inherited from Neanderthals and Denisovans affect the health of modern humans? The question is intriguing and will differ from population to population. Here, at least, is a worthy successor to the question of "did we or didn't we?"

http://www.guardian.co.uk/science/blog/ ... n-immunity
 
African fossils put new spin on human origins story
http://www.bbc.co.uk/news/science-environment-14824435
By Jonathan Amos
Science correspondent, BBC News

Click to play

Professor Chris Stringer, with the help of a cast of a fossil skull, describes the similarities that this species has with modern humans
y
Related Stories

Exciting stone tool find in Kenya
'New human-like species' revealed
Ancient creature's skull probed

The ancient remains of two human-like creatures found in South Africa could change the way we view our origins.

The 1.9-million-year-old fossils were first described in 2010, and given the species name Australopithecus sediba.

But the team behind the discovery has now come back with a deeper analysis.

It tells Science magazine that features seen in the brain, feet, hands and pelvis of A. sediba all suggest this species was on the direct evolutionary line to us - Homo sapiens.

"We have examined the critical areas of anatomy that have been used consistently for identifying the uniqueness of human beings," said Professor Lee Berger from the University of the Witwatersrand in Johannesburg

"Any one of these features could have evolved separately, but it is highly unlikely that all of them would have evolved together if A. sediba was not related to our lineage," the team leader informed BBC News.

It is a big claim and, if correct, would sideline other candidates in the fossil record for which similar assertions have been made in the past.

Theory holds that modern humans can trace a line back to a creature known as Homo erectus which lived more than a million years ago. This animal, according to many palaeoanthropologists, may in turn have had its origins in more primitive hominins, as they are known, such as Homo habilis or Homo rudolfensis.

The contention now made for A. sediba is that, although older than its "rivals", some of its anatomy and capabilities were more advanced than these younger forms. Put simply, it is a more credible ancestor for H. erectus, Berger's team claims.


The female's right hand is missing only a few bones
The sediba specimens were unearthed at Malapa in the famous Cradle of Humankind World Heritage Site, just to the northwest of Jo'burg.

They were pulled from a pit - a depression left in the ground by a cave complex that had lost its roof through erosion over time.

Identified as an adult female and a juvenile male, the two individuals were quite possibly mother and son. What seems certain is that they died together in some tragic accident that saw them either fall into the cave complex or become stuck in it. After death, their bodies were washed into a pool and cemented in time along with the remains of many other animals that got trapped in the same way.

In the months since their 2010 announcement, Professor Berger and colleagues have subjected the remains to further detailed assessment.

Age: The latest dating technologies were applied to the sediments encasing the fossils. Whereas original estimates had put the age of the remains at somewhere between 1.78 and 1.95 million years old, the new analysis has narrowed this window of uncertainty to just 3,000 years. The new age is now between 1.977 and 1.98 million years old. The refined dating is important, says the team, because it puts A. sediba deep enough in time to be a realistic ancestor to H. erectus.

Dr Robyn Pickering, from the University of Melbourne, Australia, who led the dating, told BBC News: "This is a very interesting time in human evolution because it is when we think we should be seeing the beginnings of our genus, Homo. Previously, we've had very few fossils from this time period, so the sediba fossils are remarkable in that they are so complete."

Brain: A high-resolution X-ray scan of the male specimen's skull has produced a virtual cast of its braincase. From this, the researchers estimate an adult A. sediba's brain to have been about 440 cubic centimetres in volume, or about the size of a medium grapefruit. This is smaller than much older fossils in the record such as the famous "Lucy" specimen, Australopithecus afarensis (3.2 million years), but, intriguingly, the shape is more human-like, especially at the front. This may hint at the start of the re-organisation of the brain that would be necessary to make us what we are today.


It would appear from these fossils that hip evolution was not linked to an increase in brain size
Pelvis: The pelvis is short and broad like a human pelvis. A more ancient creature like Lucy has a flatter and more flaring pelvis. A popular idea has been that the modern human pelvis evolved in tandem with the gradual growth in brain volume - facilitating the birth of babies with bigger heads. A. sediba gives the lie to this theory, says the team, because it had a modern-looking pelvis while possessing a small brain.

Hand: The right-hand of the female is very nearly complete. It is looks far more like a modern human hand than an ape hand. Its fingers are shorter relative to the thumb than in a chimpanzee. And yet, it appears to have possessed powerful muscles for grasping, suggesting A. sediba spent a lot of time clambering through the branches of trees. The team also argues that the dexterity would have been there to make simple tools.

Foot: The ankle joint is mostly human-like in form and there is some evidence for a human-like arch and Achilles tendon. But A. sediba possessed an ape-like heel and lower tibia, or shin bone. The scientists think this combination may have led to a distinctive type of walk when the creature was not climbing in trees.

Whatever the correctness of the analysis, the creature certainly has a fascinating mix of features - some archaic, some modern.

Independent scientists describe the fossils as exquisite and utterly fascinating.

Dr William Harcourt-Smith from the American Museum of Natural History in New York, commented: "One lineage of Australopithecus almost certainly led into the first member of our own genus called Homo, and from then eventually emerged modern humans.

"But some of them are side branches, and we're trying to work out which ones are and which ones aren't - and that's why this finding is so important. In many ways, these fossils are the 'smoking gun' just before the emergence of our own genus."

And Professor Chris Stringer, from London's Natural History Museum, told BBC News: "This isn't the end of the story. What maybe happening is that there were several australopithecine forms all evolving human-like features in parallel as they turned to meat-eating and tool-making and moving greater distances.

"The question now is to pull out of this mess which one is really the ancestor of the genus Homo. We know there are more remains to come from this incredible site. Let's see if other individuals also show this mix of features."

[email protected].
 
Skull points to a more complex human evolution in Africa
By Daniel Boettcher, BBC News

[Video - Professor Chris Stringer compares one of the 13,000-year-old skulls (centre) with modern (l) and ancient (r) African fossils]

Scientists have collected more evidence to suggest that ancient and modern humans interbred in Africa.
Reanalysis of the 13,000-year-old skull from a cave in West Africa reveals a skull more primitive-looking than its age suggests.
The result suggests that the ancestors of early humans did not die out quickly in Africa, but instead lived alongside their descendents and bred with them until comparatively recently.
The results are published in PLoS ONE.

The skull, found in the Iwo Eleru cave in Nigeria in 1965, does not look like a modern human.
It is longer and flatter with a strong brow ridge; features closer to a much older skull from Tanzania, thought to be around 140,000 years old.
Prof Katerina Harvati from the University of Tuebingen in Germany used new digitising techniques to capture the surface of the skull in detail.
The new technique improved upon the original measurements done with callipers by letting researchers see subtler details about the skull's surface.

"[The skull] has got a much more primitive appearance, even though it is only 13,000 years old," said Chris Stringer, from London's Natural History Museum, who was part of the team of researchers.
"This suggests that human evolution in Africa was more complex... the transition to modern humans was not a straight transition and then a cut off."

Prof Stringer thinks that ancient humans did not die away once they had given rise to modern humans.
They may have continued to live alongside their descendants in Africa, perhaps exchanging genes with them, until more recently than had been thought.
The researchers say their findings also underscore a real lack of knowledge of human evolution in the region.

But palaeontologists are not all agreed on precisely what the new analysis is telling us - or, indeed, whether it is telling us anything definitive at all. 8)
"I do not think that these findings add anything new to our view," said Prof Clive Finlayson, director of the Gibraltar Museum, who was not connected to the study.
"We have a few fossils, and no idea of natural variation within populations. That the situation is not simple and is deep and complex is what we would expect.
"In my view, it is the field of genetics that will help us most in clarifying matters," he told BBC News.

Separate research published earlier this month suggests that genetic mixing between hominin species happened in Africa up to 35,000 years ago.

http://www.bbc.co.uk/news/science-environment-14947363
 
Lock of hair pins down early migration of Aborigines
By Leila Battison, Science reporter

A lock of hair has helped scientists to piece together the genome of Australian Aborigines and rewrite the history of human dispersal around the world.
DNA from the hair demonstrates that indigenous Aboriginal Australians were the first to separate from other modern humans, around 70,000 years ago.
This challenges current theories of a single phase of dispersal from Africa.
An international team of researchers published their findings in the journal Science.

While the Aboriginal populations were trailblazing across Asia and into Australia, the remaining humans stayed around North Africa and the Middle East until 24,000 years ago.
Only then did they spread out and colonise Europe and Asia, but the indigenous Aborigines had been established in Australia for 25,000 years.
Australian Aborigines therefore have a longer claim to the land in which they now live than any other population known.

The research also highlights the exciting future possibilities of comparing the genomes of multiple individuals to track migration of small indigenous groups.

Archaeological remains are known from Australia from around 50,000 years ago, putting a maximum age of the Aborigines' settlement there.
But the history of their journey and their relationship with the indigenous people of Asia and Europe had not been solved.

It was previously thought that modern humans dispersed in one pulse out of Africa and the Middle East, and because of the distances involved, the modern Europeans would have separated from the Asians and Australians first.
Genetic information from a lock of Aboriginal hair has been used to show that the Australians set off a lot earlier.
By looking at the tiny (fraction of a percent) differences between the DNA of Aborigines and other ancient humans, the scientists show that the indigenous Australians were first isolated 70,000 years ago.

Dr Francois Balloux, of Imperial College London described how a "population expanded along the coastline because of the rich resources available there. They could walk almost the entire way because the sea level was much lower". Just one small sea crossing would be required to reach Australia.
Any potential archaeological remains of this journey, which lasted 25,000 years, would be lost to the deep sea under rising sea levels.

The remaining populations in the Middle East moved out to colonise Europe and Asia 24,000 years ago, and the aboriginal genome records some interbreeding between Asian populations and aboriginal ancestors at this time.

Discovering the history of human migration with DNA has been made possible by improvements in the techniques used to study the genome.
Traditionally, genetic divergence dates were arrived at by combining the number of unique mutations in the DNA with an assumed rate of acquiring those mutations.
Now, computationally powerful models can simulate lots of different scenarios for migration timings and directions, and researchers can compare and choose the situation that most closely matches what is seen in the genome.
By comparing the Aboriginal genome with the DNA of African, European and Han Chinese individuals it was possible to highlight the later interbreeding after initial colonisation.

Comparison with Eurasian populations show that the Australian Aborigines have a similar percentage of Neanderthal genes within their DNA as their Eurasian counterparts, suggesting that any interbreeding occurred before the Aborigines embarked on their colonising journey.

The findings of these researchers are supported by an independent study, published this week in the American Journal of Human Genetics, which looks at the characteristic DNA from an extinct, archaic form of human, the Denisovans.
Denisovans lived over 30,000 years ago, and contributed genes mostly to present-day New Guineans.
This independent study identifies a pattern of Denisovan DNA in Asian individuals that can only be explained by two separate waves of human migration: the first of Aboriginals colonising Australia, and the second involving the occupation of Asia itself.

The Aboriginal research was carried out on a single lock of hair, which was donated by a young Aboriginal man to the British anthropologist Dr A C Haddon in 1923.
"At this time, it was fashionable to take human samples," said Dr Balloux. The collection of hair was one of the more innocuous efforts of anthropologists at the time.
The researchers chose to examine the hair, as opposed to any other type of remains, for legal reasons. Hair is not classified as a human tissue.

"More important to us was that the research would be acceptable from a social and moral point of view" said Dr Balloux.To the surprise of the scientists, the people they consulted were very supportive of the study and its results. Dr Balloux explained that in the past, indigenous people have been "extremely sensitive of the motivations of western scientists".
The research has been published with "strong endorsement" from the Goldfields Land and Sea Council, the organisation that represents the Aboriginal traditional owners of parts of Western Australia, he said.

Genomics techniques like those used in this study have the potential to be used more extensively in the study of human migrations and the evolution of health and disease.
The international team next plans to look in more detail at the dispersal of modern humans out of Africa, as well as solving how and when the Americas were colonised.
Dr Balloux said he was excited about the unexpected potential of the techniques, describing it as "borderline Jurassic Park science". 8)

http://www.bbc.co.uk/news/science-environment-15020799
 
Well, thats about the height of it.

Homo Heidelbergensis Was Only Slightly Taller Than the Neanderthal
http://www.sciencedaily.com/releases/20 ... 075323.htm

Homo heidelbergensis was only slightly taller than the Neanderthal. (Credit: Image courtesy of Plataforma SINC)

ScienceDaily (June 6, 2012) — The reconstruction of 27 complete human limb bones found in Atapuerca (Burgos, Spain) has helped to determine the height of various species of the Pleistocene era. Homo heidelbergensis, like Neanderthals, were similar in height to the current population of the Mediterranean.

Along with its enormous quantity of fossils, one of the most important features of the Sima de los Huesos (SH) site in Atapuerca, Burgos, is the splendid state of the findings. They are so well conserved that the 27 complete bones from some 500,000 years ago have been reconstructed.

"The incredible collection allows us to estimate the height of species such as Homo heidelbergensis, who inhabited Europe during the Middle Pleistocene era and is the ancestor of the Neanderthal. Such estimations are based solely on analysis of the large complete bones, like those from the arm and the leg," as explained by José Miguel Carretero Díaz, researcher at the Laboratory of Human Evolution of the University of Burgos and lead author of the study that has been published in the 'Journal of Human Evolution' journal.

In addition, since bones were complete, the researchers were able to determine whether they belonged to a male or female and thus calculate the height of both men and women. "Estimations to date were based on incomplete bone samples, the length of which had to be estimated too. We also used to use formulas based on just one reference population and we were not even sure as to its appropriateness," outlines the researcher.

Since the most fitting race or ecology for these human beings was unknown, scientists used multiracial and multigender formulas to estimate the height for the entire population in order to reduce the error margin and get a closer insight on the reality. As Carretero Díaz points out, "we calculated an overall average for the sample and one for each of the sexes. The same was done with the Neanderthal and Cro-Magnon fossils."

The results suggest that both men and women in the Sima de los Huesos population were on average slightly higher than Neanderthal men and women. "Neither can be described as being short and both are placed in the medium and above-medium height categories. But, both species featured tall individuals," assured the experts.

The height of these two species is similar to that of modern day population of mid-latitudes, like in the case of Central Europe and the Mediterranean.

The humans who arrived in Europe during the Upper Palaeolithic era, Cro-Magnons or anatomically modern humans, replaced the Neanderthal populations. They were significantly taller than other human species and their average height for both sexes was higher, falling in the very tall individual category.

Height remained the same for some 2 million years.

According to the researchers, putting aside the margin corresponding to small biotype species like Homo habilis (East Africa), Homo georgicus (Georgia) and Homo floresiensis (Flores in Indonesia), all documented humans during the Early and Middle Pleistocene Era that inhabited Africa (Homo ergaster, Homo rhodesiensis), Asia (Homo erectus) and Europe (Homo antecessor, Homo heidelbergensis and Homo neanderthalensis) seemed to have medium and above-medium heights for the most part of two millions years. However, the researchers state that "amongst every population we have found a tall or very tall individual."

In their opinion, this suggests that the height of the Homo genus remained more or less stable for 2 million years until the appearance of a "ground-breaking species in this sense" in Africa just 200,000 years ago. These were the Homo sapiens, who were initially significantly taller than any other species that existed at the time.

"The explanation is found in the overall morphological change in the body biotype that prevailed in our species compared to our ancestors. The Homo sapiens had a slimmer body, lighter bones, longer legs and were taller," adds the researcher.

A lighter body aided survival

Scientists have documented various advantages that made the sapiens biotype more adaptable. These include their thermoregulatory, obstetric and nutritional make-up but in the eyes of the experts, the greatest advantage of this new body type was increased endurance and energy.

Carretero Díaz indicates that "larger legs, narrower hips, being taller and having lighter bones not only meant a reduction in body weight (less muscular fat) but a bigger stride, greater speed and a lower energy cost when moving the body, walking or running."

This type of anatomy could have been highly advantageous in terms of survival in Eurasia during the Upper Pleistocene Era when two intelligent human species (the light-bodied Cro-Magnons and Neanderthals) had to face difficult climatic conditions, drastic changes in ecosystems and ecological competition.

Story Source:

The above story is reprinted from materials provided by Plataforma SINC, via AlphaGalileo.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:

José-Miguel Carretero, Laura Rodríguez, Rebeca García-González, Juan-Luis Arsuaga, Asier Gómez-Olivencia, Carlos Lorenzo, Alejandro Bonmatí, Ana Gracia, Ignacio Martínez, Rolf Quam. Stature estimation from complete long bones in the Middle Pleistocene humans from the Sima de los Huesos, Sierra de Atapuerca (Spain). Journal of Human Evolution, 2012; 62 (2): 242 DOI: 10.1016/j.jhevol.2011.11.004
 
'Ancient' skeleton excavated in Sri Lanka
http://www.bbc.co.uk/news/world-asia-18501964

The find has been hailed by archaeologists for its importance

Related Stories

'Vampire' skeleton displayed in Bulgaria Watch
Farming 'spread by migrant wave'
Human fossils hint at new species

A complete human skeleton - which could be the oldest found so far in South Asia - has been found in Sri Lanka, archaeologists say.

It was excavated from a cave in western Sri Lanka. Officials say they will send it for carbon-dating and expect results in a month.

Other items, excavated from the same layer as the skeleton, have been confirmed as dating back 37,000 years.

Stone and bone tools were found with the skeleton.

The skeleton - thought to be homo sapiens - was found in Fa Hien Cave in the district of Kalutara, Western Province, Sri Lanka.

Human remains were also discovered at the cave in the 1960s and 1980s.

Archaeologist Nimal Perera told the Sri Lankan Daily News that the find - made a few days ago - proves that homo sapiens settled in Sri Lanka about 40,000 years ago.

He said the find is the first time that a complete pre-historic human skeleton has been unearthed in Sri Lanka, and more evidence is currently being unearthed about its eating habits, rituals and equipment made out of stone.

Some ornaments made of beads have also been excavated, as have weapons made of animal bone, Dr Perera said.
 
Hominins did not need boats to settle islands
http://www.newscientist.com/article/dn2 ... lands.html

12:00 12 July 2012 by Jeff Hecht

The early human colonisation of islands might not have been plain sailing. Instead of using boats to deliberately settle on Indonesian islands, hominins may have arrived as castaways, carried on floating debris after floods.

David Wilkinson of Liverpool John Moores University and Graeme Ruxton of the University of St Andrews, both in the UK, used population estimates from the early settlement of Polynesia to model the likely success of island settlement attempts in human prehistory.

They found that five young couples had a 40 per cent chance of giving rise to a population of 500 – or founding a population that survived for 500 years. Ten random castaways had only a 20 per cent chance of similar success. But throwing in between one and four additional castaways every 50 years raised the chances of an accidental settlement succeeding to 47 per cent.

Stone tools show that hominins – possibly Homo erectus – reached Flores 1 million years ago. The famous Homo floresiensis may have descended from this population of H. erectus. Meanwhile, a study earlier in the year concluded that Neanderthals had access to boats 100,000 years ago, which they used to reach the Greek islands of Lefkada, Kefallonia and Zakynthos, where their stone tools have been found.

The new finding suggests that in both cases the hominins could have reached the islands without boats. We already know that other mammals managed the feat: rats and Stegodon, an extinct relative of the elephant, crossed the deep-water channel between the Indonesian islands of Java and Flores. Elephants are strong swimmers, and rats could have travelled on storm debris.

Accidental colonisation of Flores by hominins would have been difficult, but not impossible, says Mike Morwood of the University of Wollongong in New South Wales, Australia. However, he adds, "the rapid colonisation of Greater Australia and major islands of western Melanesia 45,000 to 50,000 years ago indicates deliberate colonisation voyages by people using directed craft".

Journal of Human Evolution, DOI: 10.1016/j.jhevol.2012.05.013
 
Africa's Homo sapiens were the first techies
December 5th, 2012 in Other Sciences / Archaeology & Fossils

This is a Bone point from the Middle Stone Age levels at Peers Cave. The exact context is unknown (see d?Errico and Henshilwood 2007); b?g Bone tools from the Still Bay levels at Blombos Cave; b?e bone awls; f?g bone points; h?i engraved lines on tools c and g (see Henshilwood et al. 2001a; d?Errico and Henshilwood 2007); j engraved bone fragment (see d?Errico et al. 2001) 220 J World Prehist (2012) 25:205?237 123 Credit: Christopher Henshilwood

The search for the origin of modern human behaviour and technological advancement among our ancestors in southern Africa some 70 000 years ago, has taken a step closer to firmly establishing Africa, and especially South Africa, as the primary centre for the early development of human behaviour.

A new research paper by renowned Wits University archaeologist, Prof. Christopher Henshilwood, is the first detailed summary of the time periods he and a group of international researchers have been studying in South Africa: namely the Still Bay techno-traditions (c. 75 000 – 70 000 years) and the Howiesons Poort techno-tradition (c. 65 000 – 60 000 years).

The paper, entitled Late Pleistocene Techno-traditions in Southern Africa: A Review of the Still Bay and Howiesons Poort, c. 75 ka, has been published online in the Journal of World Prehistory on 6 November 2012.

Henshilwood says these periods were significant in the development of Homo sapiens behaviour in southern Africa. They were periods of many innovations including, for example, the first abstract art (engraved ochre and engraved ostrich eggshell); the first jewellery (shell beads); the first bone tools; the earliest use of the pressure flaking technique, that was used in combination with heating to make stone spear points and the first probable use of stone tipped arrows launched by bow.

These are engraved ochres from the Still Bay M1 phase at Blombos Cave (modified after Henshilwood et al. 2009). This shows; a) Two groups of incisions, one on the center and one close to the edge. In the center two joining lines form a ?Y? that is crossed by a few perpendicular parallel lines. Three incisions cross these lines; b) Two lines that cross perpendicularly on the top right margin. Converging lines produced with a single lithic point; c) this piece retains only a small area of the original engraved pattern. Three straight oblique lines incised on the top left with two sinuous lines that cross them; d) three distinct sets of lines engraved on a natural surface. Piece was then knapped and a part of the engraving removed; e) a group of sinuous lines engraved on one face. The opposite face is highly scraped and engraved with a cross-hatched pattern; and f) Cross-hatched pattern incised on one long edge. Credit: Christopher Henshilwood

"All of these innovations, plus many others we are just discovering, clearly show that Homo sapiens in southern Africa at that time were cognitively modern and behaving in many ways like ourselves. It is a good reason to be proud of our earliest, common ancestors who lived and evolved in South Africa and who later spread out into the rest of the world after about 60 000 years," says Henshilwood.

The research also addresses some of the nagging questions as to what drove our ancestors to develop these innovative technologies. According to Henshilwood answers to these questions are, in part, found in demography and climate change, particularly changing sea levels, which were major drivers of innovation and variability in material culture.

This paper is just the latest to come from Henshilwood and his teams' research on African archaeology that revolutionised the idea that modern human behaviour originated in Europe after about 40 000 years ago. There is increasing evidence for an African origin for behavioural and technological modernity more than 70 000 years ago and that the earliest origin of all Homo sapiens lies in Africa with a special focus in southern Africa.

Henshilwood writes: "In just the past decade our knowledge of Homo sapiens behaviour in the Middle Stone Age, and in particular of the Still Bay and Howiesons Poort, has expanded considerably. With the benefit of hindsight we may ironically conclude that the origins of 'Neanthropic Man', the epitome of behavioural modernity in Europe, lay after all in Africa."

Provided by Wits University

"Africa's Homo sapiens were the first techies." December 5th, 2012. http://phys.org/news/2012-12-africa-hom ... chies.html
 
Fossil human traces line to modern Asians
http://www.bbc.co.uk/news/science-environment-21123717

The person shared a common origin with the ancestors of modern Asians

Researchers have been able to trace a line between some of the earliest modern humans to settle in China and people living in the region today.

The evidence comes from DNA extracted from a 40,000-year-old leg bone found in a cave near Beijing.

Results show that the person it belonged to was related to the ancestors of present-day Asians and Native Americans.

The results are published in the journal PNAS.

Humans who looked broadly like present-day people started to appear in the fossil record of Eurasia between 40,000 and 50,000 years ago.

But many questions remain about the genetic relationships between these early modern humans and present-day Homo sapiens populations.

For example, some evidence hints at extensive migration into Europe after the last Ice Age.

And fossil finds from Red Deer Cave, also in China, and Iwo Eleru in Nigeria point to a hitherto unappreciated diversity among Late Pleistocene humans.

New technique
The team managed to extract genetic material from an ancient leg bone found in 2003 at the site of Tianyuan Cave outside Beijing.

They managed to extract the type of DNA found in the nuclei of cells (nuclear DNA) and genetic material from the cell's "powerhouses" - known as mitochondria.

They used new techniques that can identify ancient genetic information from an archaeological find, even when large amounts of DNA from soil bacteria are also present.

Analysis of the person's DNA showed that they were related to the ancestors of present-day Asians and Native Americans. But the analysis showed that this individual had already diverged from the ancestors of present-day Europeans.


The fossils were discovered in 2003 at Tianyuan near Beijing
"More analyses of additional early modern humans across Eurasia will further refine our understanding of when and how modern humans spread across Europe and Asia", said co-author Svante Pääbo, from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Research in the last few years has shown that early modern humans interbred with ancient human species such as the Neanderthals and Denisovans as they migrated from Africa and settled across the world.

Around 40,000 years ago, the Neanderthals and Denisovans were being replaced by Homo sapiens. Genetic studies of people living at this important crossover period could help scientists understand when and how this interbreeding took place.

The researchers found that the person from Tianyuan cave carried about the same proportion of Neanderthal and Denisovan DNA as people in the region today.
 
Blow to multiple human species idea
By Melissa Hogenboom
Science reporter, BBC News
http://www.bbc.co.uk/news/science-environment-24564375

The Dmanisi D4500 early Homo cranium

The 1.8 million-year-old skull is the most complete hominid skull ever found

The idea that there were several different human species walking the Earth two million years ago has been dealt a blow.

Instead, scientists say early human fossils found in Africa and Eurasia may have been part of the same species.

Writing in the journal Science, the team says that Homo habilis, Homo rudolfensis and Homo erectus are all part of a single evolving lineage that led to modern humans.

But others in the field reject this.

A team looked at the most complete hominid skull ever found, which was uncovered in Dmanisi, Georgia.

It had a small braincase, large teeth and a long face, characteristics it shares with H. habilis. But many features from the braincase were also "unique" to H. erectus.

The 1.8-million-year old skull comes from a site that has given up the biggest collection of well-preserved early-human remains known anywhere in the world.

The face of Dmanisi Skull 5
The skull had a very small braincase
The Dmanisi collection also represents the earliest evidence of primitive humans outside Africa, a group that emerged soon after early Homo diverged from Australopithecus, or "Lucy".

"We now have the best evidence for what early Homo really is," said lead author David Lordkipanidze from the Georgian National Museum in Tbilisi, Georgia.

"One of the most important things is that we have such a remarkable collection; it's very rare that you have that from one site."

The fossil remains showed a lot of variation that had previously puzzled researchers, but Prof Lordkipanidze said it was clear that these features were all from one population.

"When we looked at this variability and compared it with modern humans, you can see this is a normal range of variation," Prof Lordkipanidze told BBC News.

The skull was uncovered eight years ago and since then the team has compared it to other Homo fossils found in Africa from as early as 2.4 million years ago.

The comparative analysis of the hominid cranium revealed enough similarities for the team to consider the earliest Homo fossils as the same species as the Dmanisi hominids.

Continue reading the main story
The Dmanisi hominids

Dmanisi early humans artist's impression
The Georgian hominids lived about 1.8 million years ago and represent an early expansion of human ancestors outside Africa
They are the most complete collection of a Homo species from any site older than 300,000 years old
They had human-like spines and lower limbs that would have been well suited for long distance travel
The male of the species was much larger than the female
They also had relatively small brains and primitive upper limbs, traits which they shared with the earlier H. habilis, and even with the more primitive Australopithecus
A co-author of the study, Christoph Zollikofer from the Anthropological Institute and Museum in Zurich, Switzerland, said that if the braincase and the face of "Skull 5" had been found as separate fossils at different sites in Africa, they might have been attributed to different species.

"That's because Skull 5 unites some key features, like the tiny braincase and large face, which had not been observed together in an early Homo fossil until now.

"Furthermore, since we see a similar pattern and range of variation in the African fossil record, it is sensible to assume that there was a single Homo species at that time in Africa," Prof Zollikofer added.

"And since the Dmanisi hominids are so similar to the African ones, we further assume that they both represent the same species."

Other palaeoanthropologists, however, believe that at least three distinct species of humans co-existed in Africa.

They include Fred Spoor from University College London. He told BBC News that the methods of analysis that the team used were not sufficient to infer that these fossils were the same species.

"They do a very general shape analysis of the cranium which describes the shape of the face and braincase in broad sweeping terms," Prof Spoor Said.

Five Dmanisi skulls
The Dmanisi site has uncovered the most complete collection of a Homo species
"The problem is that those Homo species are not defined using such a broad overview of what their general cranial shape is."

He added that the very specific characteristics that had been used to define H. erectus, H. habilis and H. rudolfensis "were not captured by the landmarks that they used".

"They did not consider that the thick and protruding brow ridges, the angular back of the braincase; and some details of the base of the cranium are derived features for H. erectus, and not present in H. habilis and H. rudolfensis."

Chris Stringer at the Natural History Museum in London said that the team had made an excellent case "that this remarkable new skull, with its huge jawbone", was part of the natural variation of the Dmanisi population.

But he said he was doubtful that all of the early Homo fossils could be "lumped into an evolving H. erectus lineage".

"Only H. erectus survives and becomes successful but at the origin, nature was experimenting with how to evolve humans in terms of increasing brain size," Prof Stringer told BBC News.

"Creatures were starting to use tools and eat meat, and this drove evolution, but I think it also drove diversity. The Dmanisi group is an example of the successful species that came out of that and then carried on to spread around the old world."
 
Dogs love to eat their own vomit, so was somebody watching this and wondered what the appeal was? Always someone who has to take things that bit too far...
 
New Paleolithic sites discovered in Hanzhong Basin, Central China

Fig.1 Lithic artifacts from the Hanzhong Basin. 1, 3-4, 6, choppers; 2, 8, picks; 5, 13, scrapers; 7. hand-axe; 9, 11-12, spheroids; 10, hammer stone; 14, point. Credit: WANG Shejiang)

The catchment of Hanjiang River is regarded as one of the most important Paleolithic sites in central China. During 2009-2012, a scientific team led by Dr. WANG Shejiang, Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences, conducted surveys and discovered two new Paleolithic open-air sites in the Hanzhong Basin. Researchers unearthed 252 stone artifacts, and reported the finding in the journal of Acta Anthropologica Sinica 2014 (2). This study indicates hominins already occupied the Hanzhong Basin from approximately 600000 years ago, and provides important data for the study of human adaptive strategies and patterns in this region and as well as the Palaeolithic culture and human behavior in East Asia.

Two new Paleolithic open-air sites, Hejialiang and Yaochangwan, are located in the upper valley of Hanjiang River in the southern piedmont of the Qinling Mountains, central China. The lithic assemblage analysis suggests that the stone artifacts were made of local raw materials of pebbles/cobbles which derived from the riverbank alluvial deposits of the Hanjiang River. The lithic samples from the Hejialiang site frequently made of quartz,

Graywacke, and igneous rock, but infrequently made of quartzite and silicon limestone. The lithics of the Yaochangwan site more frequently made of quartz, quartzite and igneous rock, but infrequently made of sandstone and silicon limestone. ...
 
Society bloomed with gentler personalities, more feminine faces:

A composite image shows the facial differences between an ancient modern human with heavy brows and a large upper face and the more recent modern human who has rounder features and a much less prominent brow. The prominence of these features can be directly traced to the influence of the hormone testosterone.
Credit: Robert Cieri, University of Utah

Modern humans appear in the fossil record about 200,000 years ago, but it was only about 50,000 years ago that making art and advanced tools became widespread.

A new study appearing Aug. 1 in the journal Current Anthropology finds that human skulls changed in ways that indicate a lowering of testosterone levels at around the same time that culture was blossoming.

"The modern human behaviors of technological innovation, making art and rapid cultural exchange probably came at the same time that we developed a more cooperative temperament," said lead author Robert Cieri, a biology graduate student at the University of Utah who began this work as a senior at Duke University.

The study, which is based on measurements of more than 1,400 ancient and modern skulls, makes the argument that human society advanced when people started being nicer to each other, which entails having a little less testosterone in action.

Heavy brows were out, rounder heads were in, and those changes can be traced directly to testosterone levels acting on the skeleton, according to Duke anthropologist Steven Churchill, who supervised Cieri's work on a senior honors thesis that grew to become this 24-page journal article three years later. ...

http://www.sciencedaily.com/releases/20 ... 171114.htm
 
Back
Top