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Clogged arteries are seen as the quintessential symptom of an unhealthy modern lifestyle. But the condition was common across the ancient world, even among active hunter–gatherers with no access to junk food, a study of mummies has found. “There’s a belief that if we go back in time, everything’s going to be OK,” says cardiologist Greg Thomas of the University of California, Irvine, a senior member of the study team. “But these mummies still have coronary artery disease.” In atherosclerosis, arteries become narrowed and hardened by plaques — made up of cholesterol and immune cells called macrophages — that build up in their walls. The condition can lead to heart attacks, stroke and other cardiovascular diseases and is the leading cause of death in the developed world. A lack of exercise and a diet high in saturated fat — both of which increase levels of 'bad' cholesterol in the blood — are thought to increase the risk of plaques building up. This has led to the suggestion that to avoid heart disease we should try to live more like our hunter–gatherer ancestors, on a diet of unprocessed foods high in protein and unsaturated fats. To find out if that’s really true, Thomas and his colleagues performed CT scans on 137 mummies from four very different ancient populations: Egyptian, Peruvian, the Ancestral Puebloans of southwest America and the Unangans of the Aleutian Islands in Alaska. The Egyptians were artificially embalmed, whereas the other bodies were preserved naturally by very dry or very cold conditions. The four groups had different lifestyles — the Ancestral Puebloans were forager–farmers, for example, whereas the Unangan were hunter–gatherers with an exclusively marine diet. The researchers checked the mummies’ scans for calcified plaques in the wall of an artery or along the expected course of an artery. They diagnosed probable or definite atherosclerosis in 47 (34%) of the 137 mummies, and in all four populations, ranging from 25% of the 51 ancient Peruvians to 60% of the five Unangans. The researchers say that they found a level of disease equivalent to that in modern populations — a result Thomas describes as “a shock”. “Now we’ve scanned the common man and woman and they’ve got the same disease,” says Thomas. Rather than excess cholesterol, he suggests that high levels of inflammation — caused by smoke inhalation or chronic infection, for instance — may have triggered the disease in these individuals. But Thomas says that cardiovascular disease should not now be seen as simply a consequence of an unhealthy lifestyle. “We’ve oversold the ability to stop heart disease,” he says. “We can slow it down, but to think we can prevent it is unrealistic.”
University of Arizona geneticists have discovered the oldest known genetic branch of the human Y chromosome – the hereditary factor determining male sex. The new divergent lineage, which was found in an individual who submitted his DNA to Family Tree DNA, a company specializing in DNA analysis to trace family roots, branched from the Y chromosome tree before the first appearance of anatomically modern humans in the fossil record.
"Our analysis indicates this lineage diverged from previously known Y chromosomes about 300,000 ago, a time when anatomically modern humans had not yet evolved," said Michael Hammer, an associate professor in the University of Arizona's department of ecology and evolutionary biology and a research scientist at the UA's Arizona Research Labs. "This pushes back the time the last common Y chromosome ancestor lived by almost 70 percent."
Unlike the other human chromosomes, the majority of the Y chromosome does not exchange genetic material with other chromosomes, which makes it simpler to trace ancestral relationships among contemporary lineages. If two Y chromosomes carry the same mutation, it is because they share a common paternal ancestor at some point in the past. The more mutations that differ between two Y chromosomes the farther back in time the common ancestor lived. Originally, a DNA sample obtained from an African American living in South Carolina was submitted to the National Geographic Genographic Project. When none of the genetic markers used to assign lineages to known Y chromosome groupings were found, the DNA sample was sent to Family Tree DNA for sequencing. Fernando Mendez, a postdoctoral researcher in Hammer's lab, led the effort to analyze the DNA sequence, which included more than 240,000 base pairs of the Y chromosome.
An automated system that reconstructs ancient languages could help recover the sound of words not spoken for thousands of years. Like living things, languages evolve. Words mutate, sounds shift, and new tongues arise from old. Charting this landscape is usually done through manual research. But now a computer has been taught to reconstruct lost languages using the sounds uttered by those who speak their modern successors. Alexandre Bouchard-Côté at the University of British Columbia in Vancouver, Canada, and colleagues have developed a machine-learning algorithm that uses rules about how the sounds of words can vary to infer the most likely phonetic changes behind a language's divergence. For example, in a recent change known as the Canadian Shift, many Canadians now say "aboot" instead of "about". "It happens in all words with a similar sound," says Bouchard-Côté. The team applied the technique to thousands of word pairings used across 637 Austronesian languages – the family that includes Fijian, Hawaiian and Tongan. The system was able to suggest how ancestor languages might have sounded and also identify which sounds were most likely to change. When the team compared the results with work done by human specialists, they found that over 85 per cent of suggestions were within a single character of the actual words. For example, the modern word for "wind" in Fijiian is cagi . Using this and the same word in other modern Austronesian languages, the automatic system reconstructed the ancestor word beliu and the human experts reconstructed bali. Reconstructing ancient languages can reveal details of our ancient history. Looking at when the word for "wheel" diverges in the family tree of European languages helps us date the human settlement of different parts of the continent, for instance. The technique could improve machine translation of phonetically similar languages, such as Portuguese and French. Endangered languages could also be preserved if they are phonetically related to more widely spoken tongues, says Bouchard-Côté. He is now working on an online version of the tool for linguists to use.
The star exhibit initially promised for the British Museum’s “Ice Age Art” show will not be coming—but for a good reason. New pieces of Ulm’s Lion Man sculpture have been discovered and it has been found to be much older than originally thought, at around 40,000 years. This makes it the world’s earliest figurative sculpture. The story of the discovery of the Lion Man goes back to August 1939, when fragments of mammoth ivory were excavated at the back of the Stadel Cave in the Swabian Alps, south-west Germany. This was a few days before the outbreak of the Second World War. When it was eventually reassembled in 1970, it was regarded as a standing bear or big cat, but with human characteristics.
The ivory from which the figure had been carved had broken into myriad fragments. When first reconstructed, around 200 pieces were incorporated into the 30cm-tall sculpture, with about 30% of its volume missing.
Further fragments were later found among the previously excavated material and these were added to the figure in 1989. At this point, the sculpture was recognised as representing a lion. Most specialists have regarded it as male, although paleontologist Elisabeth Schmid controversially argued that it was female, suggesting that early society might have been matriarchal.
The latest news is that almost 1,000 further fragments of the statue have been found, following recent excavations in the Stadel Cave by Claus-Joachim Kind. Most of these are minute, but a few are several centimetres long. Some of the larger pieces are now being reintegrated into the figure. Even more exciting than the discovery of new pieces, the sculpture’s age has been refined using radio-carbon dating of other bones found in the strata. This reveals a date of 40,000 years ago, while until recently it was thought to be 32,000 years old. Once reconstruction is completed, several tiny, unused fragments of the mammoth ivory are likely to be carbon dated, and this is expected to confirm the result.
This revised dating pushes the Lion Man right back to the oldest sculptures, which have been found in two other caves in the Swabian Alps. These rare finds are dated at 35,000 to 40,000 years, but the Lion Man is by far the largest and most complex piece. A few carved items have been found in other regions which are slightly older, but these have simple patterns, not figuration.
A genetic analysis has shown that Northern European people are a mixture of two very different ancestral populations - and one of these populations is related to Native Americans. The discovery applies to the British, Scandinavians, French and some Eastern Europeans, and explains some genetic similarities among what would otherwise seem to be very divergent groups. "There is a genetic link between the paleolithic population of Europe and modern Native Americans," says Nick Patterson of the Genetic Society of America. "The evidence is that the population that crossed the Bering Strait from Siberia into the Americas more than 15,000 years ago was likely related to the ancient population of Europe." By examining DNA, his team found that one of these ancestral populations was the first farming population of Europe, whose DNA lives on today in relatively unmixed form in Sardinians and the people of the Basque Country, as well as the Druze population in the Middle East. The other ancestral population is likely to have been the initial hunter-gathering population of Europe - very different from the farmers. Today, the hunter-gathering ancestral population of Europe seems to be most in evidence in the people of far Northeastern Siberia and Native Americans.
Australia experienced a wave of migration from India about 4,000 years ago, a genetic study suggests. It was thought the continent had been largely isolated after the first humans arrived about 40,000 years ago until the Europeans moved in in the 1800s. But DNA from Aboriginal Australians revealed there had been some movement from India during this period. The researchers believe the Indian migrants may have introduced the dingo to Australia. By looking at specific locations, called genetic markers, within the DNA sequences, the researchers were able to track the genes to see who was most closely related to whom. They found an ancient genetic association between New Guineans and Australians, which dates to about 35,000 to 45,000 years ago. At that time, Australia and New Guinea were a single land mass, called Sahul, and this tallies with the period when the first humans arrived. But the researchers also found a substantial amount of gene flow between India and Australia. Prof Stoneking from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said: "We have a pretty clear signal from looking at a large number of genetic markers from all across the genome that there was contact between India and Australia somewhere around 4,000 to 5,000 years ago."
Southern Africa's bushmen, and their relatives the Khoe, veered off on their own path of genetic development 100,000 years ago, according to a new study. The split, gleaned from an analysis of genetic data, is the earliest divergence scientists have discovered in the evolution of modern humans. The Khoe and the San peoples - who speak click languages, and live across a wide swath of southern Africa from Namibia to Mozambique to South Africa - have long fascinated scientists. The San, in particular, were one of the last remaining hunter-gatherer societies, living well into the 20th century in a style anthropologists think was similar to humans' most ancient ancestors. The study published in the journal Science analyses the genes of 220 members of the Khoe and San groups. Researchers looked at 2.3 million genetic variations for each participant, learning important information about the Khoe-San and, more generally, the origins of modern humans.
Dr. Susan Hayes, a facial anthropologist and an honorary senior research fellow at the University of Wollongong in Australia, has reported results of the forensic facial reconstruction of mysterious Homo floresiensis, a primitive hominin discovered in 2003 on the Indonesian island of Flores and nicknamed the Hobbit.
Dr. Hayes’ facial approximation of the female Homo floresiensis. Dr. Hayes works predominantly with archaeological remains of anatomically modern humans, including the Lapita People (Vanuatu), the Amerindian Huarpe (Argentina), and the first Maori to inhabit New Zealand. In her new study, Dr. Hayes has used so-called facial approximation techniques to show how Homo floresiensis might have once looked. “In the media it’s often called ‘facial reconstruction’, but because I’m evidence-based and work in archaeological science, we prefer the term ‘facial approximation’,” Dr Hayes said.
European Americans have a larger proportion of potentially harmful variants than African Americans --- probably an artefact of their original migration out of Africa. The human genome has been busy over the past 5,000 years. Human populations have grown exponentially, and new genetic mutations arise with each generation. Humans now have a vast abundance of rare genetic variants in the protein-encoding sections of the genome. A study published in Nature now helps to clarify when many of those rare variants arose. Researchers used deep sequencing to locate and date more than one million single-nucleotide variants — locations where a single letter of the DNA sequence is different from other individuals — in the genomes of 6,500 African and European Americans. The findings confirm their earlier work suggesting that the majority of variants, including potentially harmful ones, were picked up during the past 5,000–-10,000 years.
Unraveling the mystery of why the inhabitants of Ikaria, an island of 99 square miles that is home to almost 10,000 Greek nationals, live so long and so well. In 2000, another island of longevity has been identified - a region of Sardinia’s Nuoro province is a place with the highest concentration of male centenarians in the world. Social structure might turn out to be more important. In Sardinia, a cultural attitude that celebrated the elderly kept them engaged in the community and in extended-family homes until they were in their 100s. Studies have linked early retirement among some workers in industrialized economies to reduced life expectancy.
For decades the origin and evolution of life was restricted to the fossil record that recorded hard-shelled life. We now know, through determination of absolute ages by radioactive decay, that this record only record the last 500 m.y. or so of life. Prior to that, life existed as soft-bodied organisms, or even earlier, as single cell bacteria (prokaryotes) or single-celled organisms with nuclei (eukaryotes). The oldest microfossils, composed of single-celled organisms that probably were similar to cyanobacteria, are 3.5 b.y. old, and are found in Western Australia (not the same locality where the very old zircon mineral grains were found). More convincing evidence for life in the Archean comes from fossil layered microbial communities called stromatolites. Although the 3.5 b.y. old microfossils are still debated, people pretty much agree that the fossil record for life is undisputable by about 3.0 b.y., and stromatolites are part of this evidence. Fossil bacteria are universally accepted for the Proterozoic, where the images (and chemical compositions) are much more clear than the fuzzy images for the 3.5 b.y. old microfossils. The Proterozoic microfossils are much more similar to the modern cyanobacteria. The occurrence of cyanobacteria early in earth's history is critical, since their metabolic "waste product" is oxygen, and it was essential to produce high levels of oxygen in the earth's atmosphere before more complex life (which requires different means of metabolism and energy storage) could evolve. In the latest part of the Proterozoic (~ 600 m.y. ago), multi-cellular, complex life is recorded in the fossil record. The figure shown above casts the origin and evolution of life into a 24 hour clock.
People with blue eyes have a single, common ancestor, according to new research. A team of scientists has tracked down a genetic mutation that leads to blue eyes. The mutation occurred between 6,000 and 10,000 years ago. Before then, there were no blue eyes. "Originally, we all had brown eyes," said Hans Eiberg from the Department of Cellular and Molecular Medicine at the University of Copenhagen. The mutation affected the so-called OCA2 gene, which is involved in the production of melanin, the pigment that gives color to our hair, eyes and skin. "A genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a 'switch,' which literally 'turned off' the ability to produce brown eyes," Eiberg said. The genetic switch is located in the gene adjacent to OCA2 and rather than completely turning off the gene, the switch limits its action, which reduces the production of melanin in the iris. In effect, the turned-down switch diluted brown eyes to blue. If the OCA2 gene had been completely shut down, our hair, eyes and skin would be melanin-less, a condition known as albinism. The mutation is what regulates the OCA2 switch for melanin production. And depending on the amount of melanin in the iris, a person can end up with eye color ranging from brown to green. Brown-eyed individuals have considerable individual variation in the area of their DNA that controls melanin production. But they found that blue-eyed individuals only have a small degree of variation in the amount of melanin in their eyes.
In a stunning technical feat, an international team of scientists has sequenced the genome of an archaic Siberian girl 31 times over, using a new method that amplifies single strands of DNA. The sequencing is so complete that researchers have as sharp a picture of this ancient genome as they would of a living person's, revealing, for example that the girl had brown eyes, hair, and skin. "No one thought we would have an archaic human genome of such quality," says Matthias Meyer, a postdoc at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. "Everyone was shocked by the counts. That includes me." That precision allows the team to compare the nuclear genome of this girl, who lived in Siberia's Denisova Cave more than 50,000 years ago, directly to the genomes of living people, producing a "near-complete" catalog of the small number of genetic changes that make us different from the Denisovans, who were close relatives of Neandertals. "This is the genetic recipe for being a modern human," says team leader Svante Pääbo, a paleogeneticist at the institute. Ironically, this high-resolution genome means that the Denisovans, who are represented in the fossil record by only one tiny finger bone and two teeth, are much better known genetically than any other ancient human—including Neandertals, of which there are hundreds of specimens. The team confirms that the Denisovans interbred with the ancestors of some living humans and found that Denisovans had little genetic diversity, suggesting that their small population waned further as populations of modern humans expanded. "Meyer and the consortium have set up the field of ancient DNA to be revolutionized—again," says Beth Shapiro, an evolutionary biologist at the University of California, Santa Cruz, who was not part of the team. Evolutionary geneticist Sarah Tishkoff of the University of Pennsylvania agrees: "It's really going to move the field forward."
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The 2013 Academy Awards were, as always, as much about making appearances as about making films, as red carpet watchers noted fashion trends and faux pas. Both Jessica Chastain and Naomi Watts wore Armani, although fortunately not the same dress. And Best Supporting Actress Anne Hathaway switched from Valentino to a controversial pale pink Prada at the last minute because her original dress looked too much like someone else's. Of course, no actress would be caught dead wearing the same style 2 years in a row. A new study of ancient beaded jewelry from a South African cave finds that ancient humans were no different, avoiding outdated styles as early as 75,000 years ago. Personal ornaments, often in the form of beads worn as necklaces or bracelets, are considered by archaeologists as a key sign of sophisticated symbolic behavior, communicating either membership in a group or individual identity. Such ornaments are ubiquitous in so-called Upper Paleolithic sites in Europe beginning about 40,000 years ago, where they were made from many different materials—animal and human teeth, bone and ivory, stone, and mollusk shells—and often varied widely among regions and sites. Even more ancient personal ornaments go back to at least 100,000 years ago in Africa and the Near East. But this earlier jewelry seems less variable and was nearly always made from mollusk shells. So some archaeologists have questioned whether these earlier ornaments played the same symbolic roles as the later ones, or even whether they were made by humans at all. In a new study in press at the Journal of Human Evolution, a team led by archaeologist Marian Vanhaeren of the University of Bordeaux in France claims to have found evidence of a relatively sudden shift in the way that shell beads were strung. The beads were found at Blombos Cave in South Africa in archaeological layers dated between 75,000 and 72,000 years ago, during a time period marked by four distinct layers of artifacts called the Still Bay tradition. This tradition includes bone awls and sophisticated stone spear points and knives, as well as beads from jewelry: sixty-eight specimens of the southern African tick shell, Nassarius kraussianus, most found clustered together and thought to be part of individual necklaces or bracelets. All the shells are perforated with a single hole, and the team's microscopic studies—as well as experiments with shells of the same species collected near the site—have suggested that they were punctured with a finely tipped bone point.
Mesolithic hunter-gatherers living on a meat-dominated, grain-free diet had much healthier mouths that we have today, with almost no cavities and gum disease-associated bacteria, a genetic study of ancient dental plaque has revealed. An international team of researchers, led by a group at the Australian Centre for Ancient DNA, University of Adelaide, extracted DNA from dental plaque from 34 prehistoric northern European human skeletons, and traced the changes in the nature of oral bacteria from the last hunter-gatherers to Neolithic and medieval farmers and modern individuals. "Dental plaque represents the only easily accessible source of preserved human bacteria," says lead author Dr Christina Adler, now associate lecturer in dentistry at the University of Sydney. The researchers found the composition of bacteria changed with the introduction of farming and again 150 years ago during the Industrial Revolution. In contrast to the hunter-gatherer and early agriculturist diet, a modern diet full of refined carbohydrates and sugars has given us mouths dominated by cavity-causing bacteria. "What we found was that the early [hunter-gatherer] groups really had a lot lower frequencies of any of the disease-associated bacteria compared to what you see today [and] that the number of species per person's mouth, or the diversity, was much higher in the past," says Adler. However, while the researchers noted that bacteria associated with dental cavities such as S. mutans became dominant around the time of the Industrial Revolution, the frequency of bacteria associated with periodontal diseases such as gingivitis has not changed much since farming began. This may have implications for the notion that gum disease and associated bacteria are a significant contributor to the recent increase in conditions such as cardiovascular disease and atherosclerotic plaques, says co-author Professor Alan Cooper, director of the Australian Centre for Ancient DNA. "It has been suggested that the presence of this permanent inflammation state along the gums was promoting an immune inflammatory response, which in turn leads to cardiovascular disease," says Cooper. "The idea was that a recent increase in the bacteria P. gingivalis [which causes gingivitis], was associated with the recent increases in cardiovascular disease, however we could show that this particular species has been fairly stable throughout the farming period." The results will no doubt be good news for advocates of the so-called 'paleolithic diet' - high in meat, low in grains. Cooper says it would be interesting to study the effects of the diet on the bacterial population of the mouths, particularly after reseeding with healthy bacteria.
University of British Columbia and Berkeley researchers have used a sophisticated new computer system to quickly reconstruct protolanguages – the rudimentary ancient tongues from which modern languages evolved. University of British Columbia and Berkeley researchers have used a sophisticated new computer system to quickly reconstruct protolanguages – the rudimentary ancient tongues from which modern languages evolved The results, which are 85 per cent accurate when compared to the painstaking manual reconstructions performed by linguists, will be published next week in the Proceedings of the National Academy of Sciences. "We're hopeful our tool will revolutionize historical linguistics much the same way that statistical analysis and computer power revolutionized the study of evolutionary biology," says UBC Assistant Prof. of Statistics Alexandre Bouchard-Côté, lead author of the study. "And while our system won't replace the nuanced work of skilled linguists, it could prove valuable by enabling them to increase the number of modern languages they use as the basis for their reconstructions." Protolanguages are reconstructed by grouping words with common meanings from related modern languages, analyzing common features, and then applying sound-change rules and other criteria to derive the common parent. The new tool designed by Bouchard-Côté and colleagues at the University of California, Berkeley analyzes sound changes at the level of basic phonetic units, and can operate at much greater scale than previous computerized tools. The researchers reconstructed a set of protolanguages from a database of more than 142,000 word forms from 637 Austronesian languages—spoken in Southeast Asia, the Pacific and parts of continental Asia.
Scientists using a "more reliable" form of radiocarbon dating have re-assessed fossils from the region and found them to be far older than anyone thought. The work appears in the journal PNAS. Its results have implications for when and where we - modern humans - might have co-existed with our evolutionary "cousins", the Neanderthals. "The picture emerging is of an overlapping period [in Europe] that could be of the order of perhaps 3,000-4,000 years - a period over which we have a mosaic of modern humans being present and then Neanderthals slowly ebbing away, and finally becoming extinct," explained co-author Prof Thomas Higham from the Oxford Radiocarbon Accelerator Unit at the University of Oxford, UK. "What our research contributes is that in southern Spain, Neanderthals don't hang on for another 4,000 years compared with the rest of Europe. And the hunch must be that they go extinct in the south of Spain at the same time as everywhere else," he told BBC News. Though once thought to have been our ancestors, the Neanderthals are now considered an evolutionary dead end. They first appear in the fossil record hundreds of thousand of years ago and, at their peak, dominated a wide range, spanning Britain and Iberia in the west to Israel in the south and Uzbekistan in the east. Our own species, Homo sapiens, evolved in Africa, and displaced the Neanderthals after entering Europe somewhere around the 45,000-year mark. No-one can say for sure what, if any, active role modern humans had in the decline of Europe's Neanderthals. What is clear though is that some mixing must have occurred somewhere at some point. This is evident from DNA studies that prove Neanderthals made a small but significant contribution to the genetics of many modern humans. However, scientists think this interbreeding could have occurred outside Europe, in the eastern Mediterranean or Middle East region (the area archaeologists call the "Levant"), and quite probably even deeper in time - some 80,000-90,000 years or so ago.
A new DNA analysis method reveals how ancient skeletons would have looked in the flesh and even predicts hair and eye color.
For years, when museums, textbooks or other outlets attempted to illustrate what a particular ancient human skeleton would have looked like in the flesh, their method was admittedly unscientific—they basically had to make an educated guess. Now, though, a group of researchers from Poland and the Netherlands has provided a remarkable new option, described in an article they published in the journal Investigative Genetics on Sunday. By adapting DNA analysis methods originally developed for forensic investigations, they’ve been able to determine the hair and eye color of humans who lived as long as 800 years ago. The team’s method examines 24 locations in the human genome that vary between individuals and play a role in determining hair and eye color. Although this DNA degrades over time, the system is sensitive enough to generate this information from genetic samples—taken either from teeth or bones—that are several centuries old (although the most degraded samples can provide information for eye color only). As a proof of concept, the team performed the analysis for a number of people whose eye and hair color we already know. Among others, they tested the DNA of Władysław Sikorski, a former Prime Minister of Poland who died in a 1943 plane crash, and determined that Sikorski had blue eyes and blonde hair, which correctly matches color photographs. For example, in the paper, the researchers analyzed the hair and eye color for a female skeleton buried in the crypt of a Benedictine Abbey near Kraków, Poland, sometime between the 12th and 14th centuries. The skeleton had been of interest to archaeologists for some time, since male monks were typically the only people buried in the crypt. The team’s analysis showed that she had brown eyes and dark blond or brown hair. The team is not sure yet just how old a skeleton has to be for its DNA to be degraded beyond use—the woman buried in the crypt was the oldest one tested—so it’s conceivable that it might even work for individuals who’ve been in the ground for more than a millenium. The researchers suggest this sort of analysis could soon become part of a standard anthropological toolkit for evaluating human remains.
Two thousand years ago, people could not go to the nearest pharmacy for Cold-Eeze, but they appear to have concocted their very own zinc remedy, according to a new analysis of ancient remnants. Scientists have characterized the mineralogical and chemical ingredients of medicine from a 2,200-year-old shipwreck, revealing new insights into the pharmaceutical practices of the ancient world. A number of small, airtight tin containers thought to contain substances for therapeutic use were recovered from the remains of the shipwreck, discovered off the coast of Italy in the late 1980s. When scientists later unsealed one of the small containers, they found six well-preserved, grey tablets, each approximately the shape of a circular makeup sponge. A preliminary DNA analysis of the tablets in 2010 had revealed around a dozen herbal components, including carrots, parsley and wild onion, bound by clay. However, the total composition and medicinal characteristics remained unknown until now. To explore potential medicinal uses, researchers employed a combination of analytical techniques, including mass spectrometry, X-ray diffraction, and spectroscopy. They found that inorganic elements accounted for 80% of the total sample. Zinc, in the form of hydrozincite and smithsonite minerals, was by far the most abundant component, comprising three-quarters of the inorganic elements. Organic components, like wheat flour, vegetable and animal fats, beeswax, pollen grains, and other herbs accounted for the other 20%. “The research highlights the presence of zinc compounds as the active ingredients,” says Gianna Giachi, a chemist at the Superintendence for the Archaeological Heritage of Tuscany, in Florence, Italy.
Predating the Maya civilization and Ancient Egypt, on December 21st 2012 the rising sun will align with the entrance to the Ancient Temple of Newgrange and illuminate its tomb. It was constructed 5,200 years ago by people with advanced knowledge of astronomy.
The Romani people—once known as “gypsies” or Roma—have been objects of both curiosity and persecution for centuries. Today, some 11 million Romani, with a variety of cultures, languages and lifestyles, live in Europe—and beyond. But where did they come from? A team of European researchers has now collected data on some 800,000 genetic variants (single nucleotides polymorphisms) in 152 Romani people from 13 different Romani groups in Europe. The team then contrasted the Romani sequences with those already known for more than 4,500 Europeans as well as samples from the Indian subcontinent, Central Asia and the Middle East. According to the analysis, the initial founding group of Romani likely departed from what is now the Punjab state in northwestern India close to the year 500 CE. From there, they likely traveled through Central Asia and the Middle East but appear to have mingled only moderately with local populations there. The subsequent doorway to Europe seems to have been the Balkan area—specifically Bulgaria—from which the Romani began dispersing around 1,100 CE. These travels, however, were not always easy. For example, after the initial group left India, their numbers took a dive, with less than half of the population surviving (some 47 percent, according to the genetic analysis). And once groups of Romani that would go on to settle Western Europe left the Balkan region, they suffered another population bottleneck, losing some 30 percent of their population. Local mixing was not constant over the past several centuries—even in the same groups. The genetic history, as told through this genome-wide analysis, reveals different social mores at different times. For example, Romani populations in Romania, Hungary, Slovakia, Bulgaria and Croatia show genetic patterns that suggest a limited pairing with local populations until recently. Whereas Romani populations in Portugal, Spain and Lithuania have genetic sequences that suggest they had previously mixed with local European populations more frequently but have “higher levels of recent genetic isolation from non-Romani Europeans,” the researchers noted in their paper.
DNA sequencing of 36 complete Y chromosomes has uncovered a previously unknown population explosion that occurred 40 to 50 thousand years ago, between the first expansion of modern humans out of Africa 60 to 70 thousand years ago and the Neolithic expansions of people in several parts of the world starting 10 thousand years ago. This is the first time researchers have used the information from large-scale DNA sequencing to create an accurate family tree of the Y chromosome, from which the inferences about human population history could be made. "We have always considered the expansion of humans out of Africa as being the largest population expansion of modern humans, but our research questions this theory," says Ms Wei Wei, first author from the Wellcome Trust Sanger Institute and the West China University of Medical Sciences. "The out-of-Africa expansion, which happened approximately 60,000 years ago, was extremely large in geographical terms with humans spreading around the globe. Now we've found a second wave of expansion that is much larger in terms of human population growth and occurred over a very short period, somewhere between 40,000 to 50,000 years ago."
The bond between man and dog has always been extremely evident, an unconditioned friendship, at least from the dog’s part, which has lead the latter to be rightfully often referred to as man’s best friend. But how, why, and when did dogs become such a significant part of our lives. By domesticating farm animals like cattle, pigs or sheep, man has come a long way in sustaining himself, and one can assert that both animal domestication and farming played a major role in man’s socio-cultural and psychological evolution. But dogs? While some parts of the world today consume dog meat, and it’s been proven that some North American cultures devised clothing from fabric made out of dog hair, it’s rather safe to say that dogs weren’t domesticated with a practical goal in mind. Man’s ubiquitous need for company might have been the cause for the first domestication attempts, and one of the first such acts might have taken place in the freezing solitude of a cave in the middle of the last ice age.
Recently, scientists have come across a 33,000 year old dog fossil in Siberia, that bears the oldest signs of domestication by man so far found. A similar find was found in Belgium, when a dog fossil from the same period was discovered. When correlating the two, it seems that dog domestication didn’t result from a single event that than sparked a cultural phenomenon, but rather that it came naturally for man to befriend canines, as these isolated fossils suggest.
Dutch linguists have developed a new method using Bayesian phylogenetic approaches to analyze the evolution of structural features in more than 50 language families. The study explores how stable over time the structural features of languages are – aspects like word order, the inventory of sounds, or plural marking of nouns. “If at least some of them are relatively stable over long time periods, they promise a way to get at ancient language relationships,” the linguists stated in the paper. “But opinion has been divided, some researchers holding that universally there is a hierarchy of stability for such features, others claiming that individual language families show their own idiosyncrasies in what features are stable and which not.” Using a large database and many alternative methods they show that both positions are right: there are universal tendencies for some features to be more stable than others, but individual language families have their own distinctive profile. These distinctive profiles can then be used to probe ancient relations between what are today independent language families. This work thus has implications for our understanding of differential rates of language change, and by identifying distinctive patterns of change it provides a new window into very old historical processes that have shaped the linguistic map of the world. It shows that there is no conflict between the existence of universal tendencies and factors specific to a language family or geographic area.
The Khoe and San peoples in southern Africa play an important role for our understanding of the evolutionary history of humans. These peoples are directly descended from the first branching of the genealogical tree of today’s humans. This is shown in a study led by Uppsala University researchers and being presented in the early online version of the journal Science today. The study is based on an analysis of 2.3 million genetic variants from seven groups of the click-speaking Khoe and San peoples, a total of 220 individuals from southern Africa. The analysis is the largest genetic study ever of the Khoe and San peoples. These peoples belong to a branch that diverged from other peoples at least 100 000 years ago. This was long before modern human´s diaspora from Africa and even long before the evolutionary diversification of Pygmies in Central Africa and before the emergence of the hunters and gatherers of East Africa. The evolutionary history of humans in Africa is much more complex than we have believed so far. Our analyses show deep divergences among the various African peoples, with the deepest divergence involving the Khoe and San peoples, says Mattias Jakobsson, Uppsala University, who directed the study. When modern humans began to spread outside Africa 60-70 000 years ago, there were already clear stratification among African populations. Our data suggest that there was no single geographical origin but that several populations contributed genes to the ancestral population that lead to today’s humans.
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