Humans evolved by sharing technology and culture

Our early ancestors, Homo sapiens, managed to evolve and journey across the earth by exchanging and improving their technology

Blombos Cave in South Africa has given us vast knowledge about our early ancestors. In 2015, four open access articles, with research finds from Blombos as a starting point, have been published in the journal PLOS ONE.

"We are looking mainly at the part of South Africa where Blombos Cave is situated. We sought to find out how groups moved across the landscape and how they interacted," says Christopher S. Henshilwood, Professor at the University of Bergen (UiB) and University of the Witwatersrand and one of the authors of the articles.

The technology of our ancestors

Since its discovery in the early 1990s, Blombos Cave, about 300 kilometres east of Cape Town, South Africa, has yielded important new information on the behavioural evolution of the human species. The cave site was first excavated in 1991 and field work has been conducted there on a regular basis since 1997 - and is on-going. Blombos contains Middle Stone Age deposits currently dated at between 100,000 and 70,000 years, and a Later Stone Age sequence dated at between 2,000 and 300 years.

The researchers from UiB and Witswatersrand have now been looking closer at technology used by different groups in this and other regions in South Africa, such as spear points made of stone, as well as decorated ostrich eggshells, to determine whether there was an overlap and contact across groups of Middle Stone Age humans. How did they make contact with each other? How would contact across groups affect one group? How did the exchange of symbolic material culture affect the group or groups?

Adapting and evolving

"The pattern we are seeing is that when demographics change, people interact more. For example, we have found similar patterns engraved on ostrich eggshells in different sites. This shows that people were probably sharing symbolic material culture, at certain times but not at others" says Dr Karen van Niekerk, a UiB researcher and co-author.

This sharing of symbolic material culture and technology also tells us more about Homo sapiens' journey from Africa, to Arabia and Europe. Contact between cultures has been vital to the survival and development of our common ancestors Homo sapiens. The more contact the groups had, the stronger their technology and culture became.

"Contact across groups, and population dynamics, makes it possible to adopt and adapt new technologies and culture and is what describes Homo sapiens. What we are seeing is the same pattern that shaped the people in Europe who created cave art many years later," Henshilwood says.
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Reference:

EurekAlert. 2016. “Humans evolved by sharing technology and culture”. EurekAlert. . Posted: February 2, 2016. Available online: http://www.eurekalert.org/pub_releases/2016-02/tuob-heb020216.php

Amid chaos of Libya, newly unearthed fossils give clues to our own evolution

Libya hasn't been terribly hospitable for scientific research lately.

Since the 2011 toppling of Muammar Gaddafi, fighters tied to various tribes, regions and religious factions have sewn chaos across that nation. Most recently, ISIS militants in Libya committed mass beheadings that triggered retaliatory bombings by neighboring Egypt.

"Currently, it is obviously very dangerous to be a Western scientist in Libya," said Christopher Beard, Distinguished Foundation Professor of Ecology and Evolutionary Biology at the University of Kansas. "Even Libyan citizens are not immune to random violence." In spite of this turmoil, Beard and a team including fellow scientists from KU's Biodiversity Institute have just published a discovery of mammal fossils uncovered in the Zallah Oasis in the Sirt Basin of central Libya. The fossils date back to the early Oligocene, between about 30 and 31 million years ago.

According to Beard, their paper in the Journal of African Earth Sciences sheds light on a poorly documented interval of our own evolutionary history, and shows climate and environmental change can utterly alter a local ecosystem -- from a wet, subtropical forest in the Eocene to a dry desert today.

This valuable knowledge makes taking calculated risks in a war-torn land worth the risk. "The most important factor is to have local collaborators who are experienced and who have a good feeling for what is impossible or dangerous," Beard said. "Our Libyan collaborator is an experienced and highly accomplished professor of geology at Tripoli University. He has excellent ties to the Libyan petroleum industry, and he knows the Sahara Desert of Libya as well as anyone. We consulted closely with him prior to our 2013 expedition, and when he gave us the green light that it was safe to return to the country -- thanks largely to his logistical arrangements with a local oil company -- we felt safe about going back, despite State Department warnings against travel to Libya."

Beard, who participated in both the Libyan fieldwork and subsequent analysis of the fossil finds, said taking care of logistics was the hardest part of the work.

"The arrangements were hard to put in place, because we had to coordinate among a team of four different nationalities, and we required the consent and active participation of our colleagues working at Zuetina Oil Company in Zallah," he said.

Working in the Zallah Oasis in Libya's Sirt Basin -- an area that has "sporadically" produced fossil vertebrates since the 1960s -- the team discovered a highly diverse and unique group of fossil mammals dating to the Oligocene, the final epoch of the Paleogene period, a time marked by a broad diversity of animals that would seem strange to us today, but also development of species critical to human evolution.

Beard said that the fossil species his team discovered in Libya were surprisingly different from previous fossils tied to the Oligocene discovered in next-door Egypt.

"The fact that we are finding different species in Libya suggests that ancient environments in northern Africa were becoming very patchy at this time, probably because of global cooling and drying which began a short time earlier," he said. "That environmental patchiness seems to have promoted what we call 'allopatric speciation.' That is, when populations of the same species become isolated because of habitat fragmentation or some other barrier to free gene flow, given enough time, different species will emerge. We are still exploring how this new evolutionary dynamic may have impacted the evolution of primates and other mammals in Africa at this time."

Because Beard's work focuses on the origin and evolution of primates and anthropoids -- the precursors to humans -- he found the Libyan discovery of a new species of the primate Apidium to be the most exciting of the fossils uncovered by the team.

"These are the first anthropoid primate fossils known from the Oligocene of Libya and the only anthropoid fossils of this age known from Africa outside of Egypt," said the researcher. "Earlier hypotheses suggested that anthropoids as a group may have evolved in response to the global cooling and drying that occurred at the Eocene-Oligocene boundary. Our new research indicates this was certainly not the case, because anthropoids had already been around for several million years in Africa prior to that boundary. But the climate change still had a deep impact on anthropoid evolution, because habitat fragmentation and an increased level of allopatric speciation took place as a result. Anthropoids, being forest dwellers, would have been particularly impacted by forest fragmentation during the Oligocene."

Unfortunately, ongoing strife in Libya makes a return visit to the Sirt Basin site impossible at the moment. Indeed, armed conflict in that nation prohibits outside scientist from visiting to safely conduct any kind of field research. "The window has now passed," Beard said. "Field research like that which our team conducts cannot begin again until the country is stabilized and the personal security of scientific researchers in the field can be assured."
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Reference:

Science Daily. 2015. “Amid chaos of Libya, newly unearthed fossils give clues to our own evolution”. Science Daily. Posted: March 9, 2015. Available online: http://www.sciencedaily.com/releases/2015/03/150309135132.htm

Skulls Tell Story of Social Growth, Scientists Say

How did our early ancestors discover the wonders of art and music and culture so long ago? They found it, according to new research, because they had finally learned to be nicer to each other.

One critical change in the course of human evolution, according to the study, was a gradual reduction in the potency of testosterone, the bad boy among hormones responsible for aggressiveness and anti-social behavior.

A team of anthropologists at Duke University studied more than 1,400 skulls from the dawn of human history to the present and found evidence that the things we love so much -- art, tools, even jewelry -- resulted from the need to form clans and work together.

Robert Cieri, then a graduate student in biology, began the study three years ago at Duke, by examining 13 human skulls more than 80,000 years old and 41 skulls between 10,000 and 38,000 years old.

He and his colleagues also analyzed 1,367 20th century skulls from 30 ethnic populations in museums around the world. Cieri, now a doctoral candidate at the University of Utah, is the lead author of a paper published in the journal Current Anthropology.

The scientists found physiological changes in the skulls that most likely resulted from hormonal changes over many generations as humans slowly moved away from isolation and into social structures that required more cooperation. The need to work together gradually reduced the influence of testosterone, which in turn changed the physical structure of the skulls, the study contends.

The human skull became more feminine, with a gentler appearance.

Testosterone, like many hormones, plays a role in the physical development, even in the embryonic stage, both in humans and other mammals.

In humans, it partly determines the lengths of the second to fourth digits. Its effect on the cranium is dramatic, as documented in a famous experiment with Siberian silver foxes. The animals were bred only for tameness, yet the structure of their skulls changed, along with other body traits, over many generations as the foxes learned to trust humans as friends.

The human skulls examined by the Duke scientists also changed over generations as the brow lost its high ridge and the skull became rounder, and more feminine.

Those changes -- not just in appearance but in the influence of testosterone -- also made it possible for humans to build ever more complex societies that were more densely populated, eventually resulting in megacities.

The sequence is this: First the need to work together, less aggression, then cranial changes, then even less aggression as humans moved from individualistic hunter gatherers to farmers and finally to urban dwellers.

All of this is based on the study of skulls, but critics -- including some who are intimately familiar with the research -- point out that much more needs to be done before this idea is accepted in a scientific discipline noted for its wide range of varying opinion.

Indeed, how we became what we are today is one of the most hotly debated topics in science, largely because the evidence itself is problematic. Ancient skulls are dated primarily on the basis of known geological ages of the soils in which they were found, which is also open to different interpretations.

But the underlying theory that the development of social structures required humans to learn to get along is widely accepted. It is the most common explanation for a human characteristic that troubled Charles Darwin: altruism. If we are driven exclusively by a selfish drive to survive and pass our genes on to future generations, why would we help anyone else? Perhaps, because we need them.

No matter how we got here, the evidence is clear that art and music and tools go a long ways back in human history. They probably began around 50,000 years ago, according to anthropologists. Recent discoveries indicate they really exploded at least 30,000 years ago.

One spectacular example is the incredibly beautiful paintings found in a cave in southern France in 1994.

Some of the paintings, numbered in the hundreds, are up to 32,000 years old, and they are exquisite. Even then, the need to communicate and preserve what was deemed valuable must have been intense.

"If prehistoric people began living closer together and passing down new technologies, they'd have to be tolerant of each other," Cieri said in releasing the study. "The key to our success is the ability to cooperate and get along and learn from one another."

The cave paintings in France indicate we learned that very early. But the situation in the world today doesn't argue that we left the savage in us behind.

Last century was the bloodiest in human history. With two world wars and uncountable battles and skirmishes, more people died from violence during that era than in any other.

But at least we have tools and jewelry. And music. And those wonderful old paintings in France.
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References:

Dye, Lee. 2014. “Skulls Tell Story of Social Growth, Scientists Say”. ABC News. Posted: August 10, 2014. Available online: http://abcnews.go.com/Technology/skulls-story-social-growth-scientists/story?id=24920557

New Genetic Test Reveals Your Ancestral Origin

For centuries, scientists have sought a biological method for tracing a person's geographic origin. Now, a group of researchers has developed such a genetic ancestry test that can pinpoint the location where a person's ancestors originated more than 1,000 years ago.

The genetic algorithm accurately predicts the country of ancestral origin for about 80 percent of people, and for isolated island populations, it can predict people's island or even village of origin in some cases, researchers report today (April 29) in a study published in the journal Nature Communications.

A person's DNA contains more than simple instructions — it also tells the story of their evolution, migrations, interbreeding and mixing, said study leader Eran Elhaik, a population geneticist at the University of Sheffield in England.

"Only genetic tools can access this vast archive and extract the exact information about our geographic origin," Elhaik told Live Science.

Researchers have been attempting to use genetic data to trace human origins for decades. The best efforts have been able to accurately trace ancestral place of origin within about 435 miles (700 kilometers) in Europe, but not very accurately in other countries.

Genetic GPS

Elhaik and his team created an algorithm that uses genetics to home in on an individual's country of origin, called the Geographic Population Structure, with the fitting acronym GPS. The method first reconstructs ancestral human gene pools around the world. Then, it analyzes an individual's genome and associates each "letter," or base, in the genetic code with one of the global gene pools, creating a kind of genetic fingerprint. Finally, it matches each fingerprint to the fingerprints of populations that have resided in a specific location for a long time.

The researchers used the GPS algorithm to trace the origins of more than 600 people worldwide. The algorithm matched 83 percent of those people to their ancestral country of origin, dating between 1,000 to 3,000 years ago.

For Southeast Asians and tropical Pacific islanders, the algorithm matched 87 percent to the island where their ancestors originated. And for a group of people from the Italian island of Sardinia, the algorithm matched 25 percent to their ancestral village, and the remainder to within 31 miles (50 km) of their villages.

For comparison, the researchers tested the best alternative algorithm, developed by researchers at the University of California, Los Angeles, on their data and found it identified the correct country of ancestral origin for only 2 percent of people.

The genetic test was less accurate for highly mixed populations, such as Bermudans and Puerto Ricans, who have experienced major demographic shifts over the past few hundred years, Elhaik said.

For people of mixed ancestry, whose parents originated in different places, the algorithm predicted the geographic midpoint of both places. In the next version of the algorithm, called GPS2, the researchers aim to predict the country of origin of each parent.

Dr. Harry Ostrer, a professor of pathology, pediatrics and genetics at Albert Einstein College of Medicine, in New York, said the new method was interesting and fairly accurate, although the results need to be replicated in other studies to verify their accuracy.

"There's a significant commercial market for ancestry testing," Ostrer said. "People want to know what their ethnic and geographic origins were."
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References:

Lewis, Tanya. 2014. “New Genetic Test Reveals Your Ancestral Origin”. Live Science. Posted: April 29, 2014. Available online: http://www.livescience.com/45215-genetic-ancestry-test-predicts-ancestral-origin.html

Human Life Span Took Huge Jump in Past Century

Humans are living longer than ever, a life-span extension that occurred more rapidly than expected and almost solely from environmental improvements as opposed to genetics, researchers said today (Oct. 15).

Four generations ago, the average Swede had the same probability of dying as a hunter-gatherer, but improvements in our living conditions through medicine, better sanitation and clean drinking water (considered "environmental" changes) decreased mortality rates to modern levels in just 100 years, researchers found.

In Japan, 72 has become the new 30, as the likelihood of a 72-year-old modern-day person dying is the same as a 30-year-old hunter-gatherer ancestor who lived 1.3 million years ago. Though the researchers didn't specifically look at the United States, they say the trends are not country-specific and not based in genetics.

Quick jump in life span

The same progress of decreasing average probability of dying at a certain age in hunters-gatherers that took 1.3 million years to achieve was made in 30 years during the 21st century.

"I pictured a more gradual transition from a hunter-gatherer mortality profile to something like we have today, rather than this big jump, most of which occurred in the last four generations, to me that was surprise," lead author Oskar Burger, postdoctoral fellow at the Max Planck Institute for Demographic Research in Germany, told LiveScience.

Biologists have lengthened life spans of worms, fruit flies and mice in labs by selectively breeding for old-age survivorship or tweaking their endocrine system, a network of glands that affects every cell in the body. However, the longevity gained in humans over the past four generations is even greater than can be created in labs, researchers concluded.

Genetics vs. environment

In the new work, Burger and colleagues analyzed previously published mortality data from Sweden, France and Japan, from present-day hunter-gatherers and from wild chimpanzees, the closet living relative to humans.

Humans have lived for an estimated 8,000 generations, but only in the past four have mortalities decreased to modern-day levels. Hunter-gatherers today have average life spans on par with wild chimpanzees.

The research suggests that while genetics plays a small role in shaping human mortality, the key in driving up our collective age lies with the advent of medical technologies, improved nutrition, higher education, better housing and several other improvements to the overall standards of living.

"This recent progress has been just astronomically fast compared to what we made since the split from chimpanzees," Burger said.

Most of the brunt of decreased mortality comes in youth: By age 15, hunters and gatherers have more than 100 times the chance of dying as modern-day people.

What's next?

"In terms of what's going on in the next four generations, I want to be very clear that I don't make any forecasts," Burger said. "We're in a period of transition and we don't know what the new stable point will be."

However, some researchers say that humans may have maxed out their old age.

"These mortality curves (that show the probability of dying by a certain age), they are now currently at their lowest possible value, which makes a very strong prediction that life span cannot increase much more," Caleb Finch, a neurogerontology professor at the University of Southern California who studies the biological mechanisms of aging, told LiveScience in an email.

Further, Finch, who was not involved in the current study, argues that environmental degradation, including climate change and ozone pollution, combined with increased obesity "are working to throw us back to an earlier phase of our improvements, they're regressive."

"It's impossible to make any reasonable predictions, but you can look, for example, in local environments in Los Angeles where the density of particles in the air predict the rate of heart disease and cancer," Finch said, illustrating the link between the environment and health.

The study is detailed today (Oct. 15) in the journal Proceedings of the National Academy of Sciences.
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References:

Stokes, Trevor. 2012. “Human Life Span Took Huge Jump in Past Century”. Live Science. Posted: October 15, 2012. Available online: http://www.livescience.com/23989-human-life-span-jump-century.html

Lao skull earliest example of modern human fossil in Southeast Asia

An ancient skull recovered from a cave in the Annamite Mountains in northern Laos is the oldest modern human fossil found in Southeast Asia, researchers report. The discovery pushes back the clock on modern human migration through the region by as much as 20,000 years and indicates that ancient wanderers out of Africa left the coast and inhabited diverse habitats much earlier than previously appreciated.

The team described its finding in a paper in Proceedings of the National Academy of Sciences. The scientists, who found the skull in 2009, were likely the first to dig for ancient bones in Laos since the early 1900s, when a team found skulls and skeletons of several modern humans in another cave in the Annamite Mountains. Those fossils were about 16,000 years old, much younger than the newly found skull, which dates to between 46,000 and 63,000 years old.

"It's a particularly old modern human fossil and it's also a particularly old modern human for that region," said University of Illinois anthropologist Laura Shackelford, who led the study with anthropologist Fabrice Demeter, of the National Museum of Natural History in Paris. "There are other modern human fossils in China or in Island Southeast Asia that may be around the same age but they either are not well dated or they do not show definitively modern human features. This skull is very well dated and shows very conclusive modern human features," she said.

No other artifacts have yet been found with the skull, suggesting that the cave was not a dwelling or burial site, Shackelford said. It is more likely that the person died outside and the body washed into the cave sometime later, she said.

The find reveals that early modern human migrants did not simply follow the coast and go south to the islands of Southeast Asia and Australia, as some researchers have suggested, but that they also traveled north into very different types of terrain, Shackelford said.

"This find supports an 'Out-of-Africa' theory of modern human origins rather than a multi-regionalism model," she said. "Given its age, fossils in this vicinity could be direct ancestors of the first migrants to Australia. But it is also likely that mainland Southeast Asia was a crossroads leading to multiple migratory paths."

The discovery also bolsters genetic studies that indicate that modern humans occupied that part of the world at least 60,000 years ago, she said.

"This is the first fossil evidence that supports the genetic data," she said.

The researchers used radiocarbon dating and luminescence techniques to determine the age of the soil layers above, below and surrounding the skull, which was found nearly 2 1/2 meters (about 8.2 feet) below the surface of the cave.

Researchers at Illinois used uranium/thorium dating to determine the age of the skull, which they determined was about 63,000 years old.

Research fellow Kira Westaway, of Macquarie University in Australia (who dated the soils around the famous "hobbit" fossil found on Flores Island in Indonesia in 2003), conducted the luminescence analyses. These techniques measure the energy retained in crystalline particles in the soil to determine how much time has elapsed since the soil was last exposed to heat or solar radiation. She found that the layer of soil surrounding the fossil had washed into the cave between 46,000 and 51,000 years ago.

"Those dates are a bit younger than the direct date on the fossil, which we would expect because we don't know how long the body sat outside the cave before it washed in," Shackelford said.

"This fossil find indicates that the migration out of Africa and into East and Southeast Asia occurred at a relatively rapid rate, and that, once there, modern humans weren't limited to environments that they had previously experienced," she said. "We now have the fossil evidence to prove that they were there long before we thought they were there."
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References:

EurekAlert. 2012. "Lao skull earliest example of modern human fossil in Southeast Asia". EurekAlert. Posted: August 20, 2012. Available online: http://www.eurekalert.org/pub_releases/2012-08/uoia-lse081712.php

Multimillion-year-old skull may hold key to human origins

Scientists in Paris show 20-million-year-old skull they hope will help with the study of human ancestry.

Man may be a distant relatives of chimpanzees and bonobo monkeys, but scientists working in Uganda came back to Paris with a new addition to the primates' family picture.

Found amid the layers of sediment beneath the volcanoes of the Karamoja region, on the Napak XV hillside, scientists said the Ugandapithecus skull is the most complete of its kind to have ever been unearthed.

The discovery of the skull represents the culmination of more than 25 years of work and an arduous search process by paleontologists across grassy inclines.

"It's the first time we've got a real good sample of Ugandapithecus Major. Before that, it was known by jaw fragments, isolated teeth, a few postcranial bones. But here, we really have a good idea for the first time of what the whole skull might have looked like," said Dr Martin Pickford, one of the paleontologists who discovered the skull.

The fossil's position between various volcanic levels allows scientists to put an age to the skull, and despite the lack of tissue for DNA analysis, Dr Pickford estimates the its age at around 20 million years.

The British paleontologist said the discovery would allow scientists to fill a gap in the lineage of primates but said the Ugandapithecus could very well have become extinct without leading to the birth of man.

The discovery is also important in that it marks the first year of archeological excavation in Uganda without the need for military escorts.


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References:

2011. "Multimillion-year-old skull may hold key to human origins". Telegraph. Posted: September 19, 2011. Available online: http://www.telegraph.co.uk/science/science-news/8775512/Multimillion-year-old-skull-may-hold-key-to-human-origins.html

Bioarchaeology helps identify origins of a people

Christopher Stojanowski “reads” bones to understand the past and its peoples and the Arizona State University bioarchaeologist, who specialises in dental anthropology, is able to extract information from human remains that tell a great deal about that person’s life, as well as his or her cause of death. Inherited physical features, injuries, disease and nutrition are among the facets Stojanowski deciphers when examining a skeleton.

Expanding that approach to a collection of remains, he is able to piece together the origin and “life-path” of an entire people.

“Ethnogenesis – the emergence of a people – is a complex topic and not typically considered in bioarchaeology,” said Stojanowski, who is an associate professor in the School of Human Evolution and Social Change in the College of Liberal Arts and Sciences.

Stojanowski focused his work in two areas: North Africa and the Southeast United States. He promotes the fact that evolutionary research does not have to be historical and descriptive. He explained,“You can use evolutionary analyses to say something a bit more humanistic about the human past”

Recently his research on the early Christianised indigenous peoples of the American Southeast is beginning to attract attention; this is a subject he was first drawn to after working on a field school at a Spanish Mission outside Tallahassee, Florida.

His research in this arena forms the basis of his latest book, “Bioarchaeology of Ethnogenesis in the Colonial Southeast,” awarded the 2011 Southern Anthropological Society’s James Mooney Prize, which recognizes distinguished research on the American South and its peoples.

The book revolves around data Stojanowski gathered from cemetery remains and then analysed to trace the evolving social identities of Native Americans living in Florida’s Spanish missions during the 17th century.

Applying biological, social and historical lenses to the material, he brings to light patterns of epidemic disease and population decline, slave raiding and fugitivism from the Spanish missions. He makes the case for native Catholic populations of Florida being subjected to prejudice by the Spanish and English, as well as England’s indigenous allies, which led to the forging of a common social experience and gave rise to the development of a Seminole identity during the 18th century.

Stojanowski now intends to use the same methodology and concentrate on the people of North Africa. “While working with historic populations has been interesting, I can’t help but think about the fact that most of human existence was spent in smaller hunter-gatherer societies, and my work in North Africa focuses on these peoples,” he stated.

Though his specialisation is in the Americas, Stojanowski notes that his research in one region informs the other. “Much of the work on Spanish colonial Florida relates to declining health with agriculture and Spanish contact,” he said. “In North Africa, there is a nice parallel where the shift from food collecting to food production entailed increasing mobility and a focus on cattle pastoralism rather than settled agricultural villages, as in the Near East.”

Stojanowski continues to work on refining methods of analysis with respect to inherited features of the bones and teeth. He teaches courses on a number of topics, from human evolution to forensic and dental anthropology.

He continues to work on the short and long-term effects of microevolution and demography on human community formation, manifestations of identity and ethnicity and transformation in community organization. His research focuses on both colonial period processes of tribal ethnogenesis and long-term relationships between cultural and biological variation. Stojanowski’s interest in modelling long-term relational processes requires use of archaeological data.

For more information:

Christopher Stojanowski

Stojanowski, C.M. (2010). Bioarchaeology of Ethnogenesis in the Colonial Southeast. University of Florida Press.

Knudson, K.J. & Stojanowski, C. M. (editors) (2009). Bioarchaeology and Identity in the Americas. Gainesville: University of Florida Press.

Stojanowski, C. M. & Duncan, W.N. (2008). Anthropological Contributions to the Cause of the Georgia Martyrs. Occasional Papers of the Georgia Southern Museum, Macon,GA: Georgia Southern Museum.

Ethnogenesis (Wikipedia)

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References:

Past Horizons. 2011. "Bioarchaeology helps identify origins of a people". . Posted: June 30, 2011. Available online: http://www.pasthorizonspr.com/index.php/archives/06/2011/bioarchaeology-helps-identify-origins-of-a-people