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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Topic: Anthropology news updates
    Posted: 27-Oct-2019 at 14:20

Descendants of early Europeans and Africans in US carry Native American genetic legacy


Many people in the U.S. do not belong to Native American communities but still carry bits of Native American DNA, inherited from European and African ancestors who had children with indigenous individuals during colonization and settlement. In a new study published 19th September in PLOS Genetics, Andrew Conley of the Georgia Institute of Technology and colleagues investigate this genetic legacy and what it can tell us about how non-natives migrated across the U.S.

When Europeans colonized North America, infectious diseases and violent conflict greatly reduced the numbers of Native Americans living on the continent. Their DNA lives on, however, not only in recognized Native American tribes, but also in the descendants of Europeans and enslaved Africans that settled within the country. To better understand this genetic reservoir, researchers analyzed patterns of Native American ancestry from genomic data collected from descendants of African slaves, and Spanish and Western European settlers.

The analysis showed that African descendants had low levels of Native American ancestry, consistent with the two groups mixing in the Antebellum South, followed by African American dispersal in the Great Migration. European descendants had the lowest amount of Native American ancestry, and showed a historical pattern of continual but infrequent mixing between local Native American groups and European settlers as they moved westward. Spanish descendants had the highest and most variable amounts of Native American ancestry, and their profiles showed regional patterns reflecting the different waves of Spanish-descended immigrants that moved into the country. Native American DNA was sufficient to distinguish between descendants of very early Spanish settlers in the U.S., known as Hispanos or Nuevomexicanos, and descendants of subsequent immigrants arriving from Mexico.

"The presence of Native American genetic ancestry among individuals who do not self-identify as Native American can also be leveraged to broaden genomic medicine and include population groups currently underserved and underrepresented in genomic databases," said author Andrew Conley. "For future studies, we are very interested to use this rich genomic resource to study the distribution of health-related genetic variants in the Native American genomic background."

Overall, the study shows that much of the genetic legacy of the original inhabitants of the area that is now the continental U.S. can be found in the genomes of the descendants of European and African immigrants to the region. By making use of large genomic databases, the new study adds insight into the current discussion of the meaning of Native American identity and its distinction from genetic ancestry.

http://https://www.sciencedaily.com/releases/2019/09/190919142344.htm



Edited by TheAlaniDragonRising - 27-Oct-2019 at 14:22
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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 20-Jul-2018 at 16:50

The New Story of Humanity's Origins in Africa



There is a decades-old origin story for our species, in which we descended from a group of hominids who lived somewhere in Africa around 200,000 years ago. Some scientists have placed that origin in East Africa; others championed a southern birthplace. In either case, the narrative always begins in one spot. Those ancestral hominids, probably Homo heidelbergensis, slowly accumulated the characteristic features of our species—the rounded skull, small face, prominent chin, advanced tools, and sophisticated culture. From that early cradle, we then spread throughout Africa, and eventually the world.

But some scientists are now arguing that this textbook narrative is wrong in its simplicity, linearity, and geography. Yes, we evolved from ancestral hominids in Africa, but we did it in a complicated fashion—one that involves the entire continent.

Consider the ancient human fossils from a Moroccan cave called Jebel Irhoud, which were described just last year. These 315,000-year-old bones are the oldest known fossils of Homo sapiens. They not only pushed back the proposed dawn of our species, but they added northwest Africa to the list of possible origin sites. They also had an odd combination of features, combining the flat faces of modern humans with the elongated skulls of ancient species like Homo erectus. From the front, they could have passed for us; from the side, they would have stood out.

Fossils from all over Africa have modern and ancient traits in varied combinations, including the 260,000-year-old Florisbad skull from South Africa; the 195,000-year-old remains from Omo Kibish in Ethiopia; and the 160,000-year-old Herto skull, also from Ethiopia. Some scientists have argued that these remains represent different subspecies of Homo sapiens, or different species altogether.

But perhaps they really were all Homo sapiens, and our species simply used to be far more diverse than we currently are. “If you look at skulls, you’ll see different features of modern humans arising in different locations at different times,” says Eleanor Scerri, an archaeologist at the University of Oxford. And the reason for that, she says, is that “we’re a species with multiple African origins.”

She and others argue that humans originated from several diverse populations that lived across Africa. Separated from each other by geographical barriers, they mostly evolved in isolation, and each group developed some of our hallmark traits, but not others. But their separation wasn’t constant: As a changing climate remodeled the African landscape, greening deserts and drying out forests, those early humans were repeatedly drawn together and pulled apart. Whenever they met, they mated and mingled, exchanging genes and ideas in a continent-wide melting pot that eventually coalesced into the full bingo of features that you or I might recognize.

This theory, known as “African multiregionalism,” is a fundamentally different view of how we came to be. It’s saying that no single place or population gave rise to us. It’s saying that the cradle of humankind was the entirety of Africa.

Scerri recently convened with 22 other anthropologists, archaeologists, geneticists, and climatologists in London to review the evidence for African multiregionalism. Their discussions are described in a paper that is published today, and that Mark Thomas, a co-author, describes as a call to arms. “We’re saying that it’s extremely unlikely that humans evolved in one location and then spread throughout the world,” he says. “Our ancestry will have reached to many, many corners of Africa.”

“It’s a good paper and I definitely agree,” says Louise Leakey, who has long studied hominid fossils in East Africa. “The numerous finds that have emerged from different sites in Africa [suggest] a patchwork of highly structured populations living across the continent.”

This can be a tricky concept to grasp, because we’re so used to thinking about ancestry in terms of trees, whether it’s a family tree that unites members of a clan or an evolutionary tree that charts the relationships between species. Trees have single trunks that splay out into neatly dividing branches. They shift our thoughts toward single origins. Even if humans were widespread throughout Africa 300,000 years ago, surely we must have started somewhere.

Not so, according to the African-multiregionalism advocates. They’re arguing that Homo sapiens emerged from an ancestral hominid that was itself widespread through Africa, and had already separated into lots of isolated populations. We evolved within these groups, which occasionally mated with each other, and perhaps with other contemporaneous hominids like Homo naledi.

The best metaphor for this isn’t a tree. It’s a braided river—a group of streams that are all part of the same system, but that weave into and out of each other.

These streams eventually merge into the same big channel, but it takes time—hundreds of thousands of years. For most of our history, any one group of Homo sapiens had just some of the full constellation of features that we use to define ourselves. “People back then looked more different to each other than any populations do today," says Scerri, “and it’s very hard to answer what an early Homo sapiens looked like. But there was then a continent-wide trend to the modern human form.” Indeed, the first people who had the complete set probably appeared between 40,000 and 100,000 years ago.

Our behavior likely evolved in the same patchwork way. For a few million years, hominids made the same style of large stone handaxes from one millennium to the next. But that technological stagnation ended around 300,000 years ago—the same age as the earliest Homo sapiens fossils. From that time period, archeologists have recovered new kinds of specialized and sophisticated stone tools, like awls and spear tips.

These tools of the so-called Middle Stone Age show that the modern human mind developed at roughly the same time as the modern human body. And they hint that this transition happened at a continental scale, for such tools have been found at Jebel Irhoud in Morocco, at Olorgesaillie in Kenya, and at Florisbad in South Africa, with regional differences at each site.  

There’s one large potential problem with the African multiregionalism story. Genetic studies of today’s African populations suggest that they diverged from one another between 100,000 and 150,000 years ago—far later than the early, continent-wide origin suggested by the bones and tools. That deep and broad origin might be right, “but, it’s not something that we geneticists have formally tested,” says Brenna Henn from UC Davis, who is an author on the new paper. “We have discussed ways of doing that, but there’s no published paper yet saying that there is deep population structure in Africa.”

But the DNA of today’s Africans has been shaped by more recent population upheavals that have obscured the goings-on of 300,000 years ago. What’s more, the studies that analyzed this modern DNA have largely relied on tree-like population models in which a single lineage grows from a single place—exactly the scenario that proponents of African multiregionalism say is wrong. “In science, we use simple models for good reasons, because often we don’t have sufficient data to inform more complex models,” says Thomas, who is a geneticist himself. “But there’s a difference between using simple models and believing in them.”

“We’re just at the beginning of trying to figure out how to refine this new theory,” says Scerri. “To know more about what happened, we need to get more data from many of the gaps in Africa. The earliest Homo sapiens fossils we have come from 10 percent of Africa, and we’re extrapolating to 90 percent of the continent. Most of it remains unexplored. We’re effectively saying those places aren’t worth looking at because we have the answer from 10 percent. How can we possibly know that?”

http://https://www.theatlantic.com/science/archive/2018/07/the-new-story-of-humanitys-origins/564779/



Edited by TheAlaniDragonRising - 20-Jul-2018 at 17:01
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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 10-Jan-2018 at 19:23

Study may shed new light on dispersal of early modern humans

A recent study* of lithic artifacts recovered decades ago from the Mount Carmel (in Israel)Skhul Cave suggests, according to the study authors, that the occupation of the Levant by early modern humans during the Pleistocene was not as simple and straight-forward as the traditionally accepted paradigm has depicted. 

Archaeological and fossil finds from caves in the Levant, particularly the Skhul and Qafzeh caves in northern Israel, have often been cited as evidence to support the popular theory that early modern humans left Africa in a single wave perhaps 100,000+ years ago and occupied locations in the Levant, only to be snuffed out due to environmental change and the lack of more advanced stone tool and weapon technology before their descendants could colonize further eastward into greater Southwest Asia and the Far East. It has been portrayed as a short-lived movement, with a more successful dispersal out of Africa occurring later, around 60 - 70,000 years ago, based on the interpretation of other finds and genetic evidence. Recent findings in other parts of the world, including China and other regions, however, have turned up evidence for early modern human occupation that challenge the dating of the latter dispersal model by thousands of years.

Enter here a recent study of a collection of lithic artifacts from Skhul Cave, a total of 270 samples, currently housed at the Pitt River Museum (PRM), University of Oxford. In that study, Huw S. Groucutt of the University of Oxford and colleagues analyzed 56 stone cores, 85 Levallois flakes, 47 non-Levallois flakes, 81 retouched stone tools and 1 hammerstone, providing the first in-depth, complete examination and description of the assemblage using modern techniques of analysis. In the process, they also compared them to lithics excavated at other paleolithic sites and integrated their findings with the paleontological and chronometric (dating) data from previous research of the Skhul and Qafzeh caves. The latest chronological data from Skhul and Qafzeh suggests the artifacts were made and used about 130 - 120,000 and 95,000 years ago, respectively. This places the artifacts, and the early modern human fossils excavated in the caves, among the first early modern humans outside of Africa known to date. 

By analyzing the artifacts within the context of finds from other sites, the stratigraphic context of the cave, and paleo-climate data, the authors hypothesize that the dispersal of and occupation by early modern humans in the Levant may have been longer and more complex than previously modeled. Write Groucutt and colleagues, “accumulating the multidisciplinary data, including the analysis of the PRM Skhul lithic assemblage we have presented, increasingly suggest that there were multiple dispersals of Homo sapiens out of Africa in MIS 5 [between 130,000 and 80,000 years ago], corresponding with humid phases, and alternating with phases of aridity.”* With this conclusion, the authors also recognize that other hypotheses could explain their results, such as the evolution of the Skhul and Qafzeh hominids from an indigenous Middle Pleistocene hominid population in southwest Asia.

Skhul Cave was initially excavated by Theodore McCown in 1931 and 1932. Excavations eventually yielded lithic tools and other finds, including human fossil remains representing seven adults and three children, some of whom were suggested by the excavators as having been intentionally buried. In addition to the lithic tools, perforated Nassarius shells thought to have been imported to the caves from a different location were also discovered. The discoverers have suggested that these people may have collected and used them as decorative beads, a behavior distinctly more ‘advanced’ than what is attributed to much earlier hominid species. The morphological features of the fossils show characteristics identified with both neanderthals and modern humans, and though they were initially classified as neanderthals, today the generally accepted classification is that of archaic (early) modern human. The specimens are thought to represent some of the earliest modern humans to occupy regions outside of Africa. The finds in both the Skull and Qafzeh caves provide evidence to support the theory that early modern humans and neanderthals lived concurrently in Eurasia for a time, and may even have interbred in the Levant. 

Although the initial investigations at Skhul in the 1930’s employed techniques and methodology that are considered inadequate by modern standards, and the collection analyzed does not represent the complete assemblage of all lithics recovered from the site, Groucutt and colleagues determined nevertheless that the artifact sampling met the requirements for making some valid observations and drawing conclusions for a hypothesis worth testing at other digs and through future studies. “We have described the Skhul lithic assemblage acknowledging its limitations in terms of excavation methods and so on, and formulated hypotheses that can be tested by multidisciplinary analyses of new sites,” the study authors concluded.*   

http://popular-archaeology.com/issue/winter-2018/article/study-may-shed-new-light-on-dispersal-of-early-modern-humans

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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 06-May-2017 at 15:50

How migrations and other population dynamics could have shaped early human culture


Something odd happened in the transition from the Middle to the Upper Paleolithic, around 50,000 years ago. Modern humans and their immediate ancestors had been using tools for a few million years prior, but the repertoire was limited. Then, all of sudden, there was an explosion of new tools, art and other cultural artifacts.

What caused that change has been the subject of much debate. Maybe brainpower reached a critical threshold. Maybe climate change forced our prehistoric kin to innovate or die. Maybe it was aliens.

Or maybe it was the result of populations growing and spreading throughout the land, Stanford researchers write in Royal Society Interface. That certainly could explain some other curious features of Paleolithic culture—and it could mean that a number of paleontologists' inferences about our genetic and environmental past are, if not wrong, not as well supported as they had thought.

Cultural bursts

"One captivating observation is if you look at the archaeological record, it seems to be highly punctuated" leading up to the Upper Paleolithic, said Oren Kolodny, a postdoctoral fellow in the lab of Marcus Feldman, a professor of biology. In other words, Kolodny said, the Paleolithic was a time marked by periods of slow change separated by bursts of cultural innovation.

"Those cultural bursts have been taken as evidence of an external change," such as genetic or environmental shifts, said Nicole Creanza, who led the study with Kolodny while a postdoctoral fellow in Feldman's lab. "But to some extent, Oren, Marc and I felt that the simplest explanation could be that culture itself is capable of behaving in a punctuated fashion," said Creanza, who is now an assistant professor of biological sciences at Vanderbilt University.

A search for something simpler

The researchers wondered, how could culture create these bursts of innovation?

In a 2015 paper, Kolodny, Creanza and Feldman, who is also co-director of Stanford's Center for Computational, Evolutionary and Human Genomics, argued that human culture could have evolved through several distinct kinds of advance. First, some ideas emerge as "lucky leaps," Kolodny said—perhaps an early human witnessed a mouse get trapped in a tangle of grass, and the hunting net was born. Other ideas could emerge either as extensions of those leaps or as combinations of other ideas or technologies. Finally, groups can also lose ideas, as prehistoric Tasmanians did when they lost, incredibly, the knowledge of how to fish, Kolodny said.

Aided by computer simulations, the team showed that combining the three kinds of advance could have led directly to bursts of innovation, as seen in the archaeological record. They also found that at the point where new ideas balance out with lost ones, the number of ideas a population can support increases dramatically with population size. A population twice the size, Kolodny, Creanza and Feldman's model predicted, could support much more than twice the number of ideas.

Migration and other game changers

In their latest paper, Creanza, Kolodny and Feldman, who is also the Burnet C. and Mildred Finley Wohlford Professor in the School of Humanities and Sciences, combined those conclusions with two new components. First, they considered migrations between otherwise distinct populations and assumed that such travel is more likely in larger populations. Second, they studied what would happen if certain major innovations, such as domesticating plants or developing hunting knives, helped grow the population.

The updated model made a number of predictions that at least qualitatively resemble what archaeologists know about cultural evolution in the Paleolithic.

First, when population sizes are small and migration is relatively rare, a pattern of cultural booms and busts is likely. Essentially, the occasional travel may bring a new idea, setting off a boom. Then, without a steady stream of new ideas or population growth - that is, a steady stream of new brains to contain all those new ideas - some ideas will be lost to time.

Innovations that encouraged population growth, however, can have lasting effects, since even slight increases in population size can support a disproportionate increase in innovation.

Migration can do something similar. As travel increases, it bridges societies, allowing for an exchange of ideas that creates a complex of interrelated cultures. And as travel becomes common, smaller groups effectively merge into one large population, with vastly more capacity for innovation. In fact, that can create a feedback loop: populations grow, contact with others increases, innovation results and populations grow even more....

http://popular-archaeology.com/issue/spring-2017/article/how-migrations-and-other-population-dynamics-could-have-shaped-early-human-culture



Edited by TheAlaniDragonRising - 06-May-2017 at 16:01
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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 10-Apr-2017 at 21:13

Prehistoric Native Americans farmed macaws in 'feather factories'

To ancient peoples of the American Southwest, a macaw’s brilliant feathers weren’t just adornments. They were status symbols and spiritual emblems — so precious, in fact, that macaws were kept in captivity and deliberately plucked of their plumage, new evidence suggests.

Macaw skeletons from three prehistoric pueblos in New Mexico bear signs of feather harvesting, according to analysis presented on 31 March at a meeting of the Society for American Archaeology in Vancouver, Canada. But the skeletons also hint that the macaws’ handlers went to great lengths to care for their demanding charges. “People were doing their utmost to keep them alive,” says Randee Fladeboe, an archaeologist at the University of Florida in Gainesville who analysed the macaw bones.

Archaeologists studying the ancient Native Americans called the Puebloans and nearby groups have found macaw bones and feathers dating from ad 300 to ad 1450 at sites ranging from Utah in the American Southwest to Chihuahua in Mexico. It is likely that many of these birds were imported; there is scanty evidence of macaw breeding, except at one Mexican site, and many macaws are tropical. The highly prized scarlet macaw (Ara macao), for example, lives at least 500 kilometres to the southeast.

Fladeboe examined the wing bones of 17 scarlet and military macaws (Ara militaris) from three pueblos. Fifteen of the birds had small bumps marring the upper surfaces of their wing bones.

A macaw’s flight feathers are rooted in the bone, so pulling them out can cause bleeding and infection, Fladeboe says. Multiple infections, or a combination of infection and malnutrition, lead to bumps like those on the skeletons. Macaws do sometimes yank out their own feathers, but the ancient bones show traces of multiple feather loss along their entire lengths and on both right and left wings. To Fladeboe, it seems unlikely that 15 of the 17 macaws she studied would strip themselves so methodically.

Tough old birds

One macaw had suffered two broken wings, and its beak bore signs of attacks from other macaws. Its bones also show irregularities from either malnutrition or illness. This macaw probably would not have survived without hand-feeding and protection, Fladeboe says.

Fladeboe makes a “good preliminary case” that the birds were plucked by humans, says zooarchaeologist Erin Keenan Early at Texas State University in San Marcos, who thinks the evidence that the birds were well cared for is also credible. Fladeboe plans to do computerized tomography scanning of the bones to confirm her early results.

Macaws that were stressed by captivity and feather removal may have engaged in “self-destructive and otherwise aggressive behavior, making them quite difficult to care for”, says zooarchaeologist Meredith Wismer of the University of Iowa in Iowa City. Fladeboe thinks that the birds’ caretakers probably learned to soothe the macaws; happy macaws have more attractive feathers. 


Few sites had more macaws than Chaco Canyon, a cluster of settlements in New Mexico. Chaco’s Pueblo Bonito even had what seems to be an aviary, complete with a layer of guano 25 centimetres thick. A radiocarbon analysis demonstrated that macaws were living there in the late 1000s and early 1100s, even as the pueblo was heading towards collapse.

Earlier research had shown that birds were imported to the pueblo when it was flourishing1. But seemingly the pueblo’s access to macaws “continued throughout the rise and decline of Chaco”, illustrating the birds’ importance, says archaeologist Adam Watson of the American Museum of Natural History in New York City, who presented the new dates at the meeting on 30 March.

Macaw keepers at places such as Chaco Canyon clearly had to go to great lengths to procure the water and food the birds needed, Fladeboe says. To ancient Southwestern peoples, the macaws served a role befitting their powers as ambassadors to the underworld and bringers of rain. The macaws’ caretakers “did obviously care for the birds”, she says. “To say that they only cared about them [for] their feather output would be to do them a disservice.”

http://www.nature.com/news/prehistoric-native-americans-farmed-macaws-in-feather-factories-1.21803

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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 18-Feb-2017 at 23:14

Linguist's 'big data' research supports waves of migration into the Americas

University of Virginia linguistic anthropologist Mark A. Sicoli and colleagues are applying the latest technology to an ancient mystery: how and when early humans inhabited the New World. Their new research analyzing more than 100 linguistic features suggest more complex patterns of contact and migration among the early peoples who first settled the Americas.

The diversity of languages in the Americas is like no other continent of the world, with eight times more "isolates" than any other continent. Isolates are "languages that have no demonstrable connection to any other language with which it can be classified into a family," Sicoli said. There are 26 isolates in North America and 55 in South America, mostly strung across the western edge of the continents, compared to just one in Europe, eight in Africa and nine in Asia.

"Scientists in the past few decades have rethought the settlement of the Americas," Sicoli said, "replacing the idea that the land which connected Asia and North America during the last ice age was merely a 'bridge' with the hypothesis that during the last ice age humans lived in this refuge known as 'Beringia' for up to 15,000 years and then seeded migrations not only into North America, but also back into Asia."

In a Feb. 17 presentation to the annual meeting of the American Association for the Advancement of Science in Boston, Sicoli will join other scientists discussing "Beringia and the Dispersal of Modern Humans to the Americas." Since much of Beringia, theorized to have been located generally between northwest North America and northeastern Asia, has been under water for more than 10,000 years, it has been challenging to find archaeological and ecological evidence for this "deep history," as Sicoli calls it.

Recent ecological, genetic and archaeological data support the notion of human habitation in Beringia during the latest ice age. The new linguistic research methods, which use "big data" to compare similarities and differences between languages, suggest that such a population would have been linguistically diverse, Sicoli said.

In "Linguistic Perspectives on Early Population Migrations and Language Contact in the Americas," Sicoli shows how big data analyses point to the existence of at least three now-extinct languages of earlier migrations that influenced existing Dene and Aleut languages as they moved to the Alaska coast. The data comparing dozens of indigenous languages support phases of migration for the Dene languages and multilingual language contact systems along the Alaska coast, which potentially involved languages related to current linguistic isolates. Traces of such language contacts support that the mixing populations also mixed their languages as part of human adaptation strategies for this region and its precarious environment.

"The computational methods give us traction on questions that have been unanswered," said Sicoli, who has been working in collaboration with Anna Berge of the University of Alaska and Gary Holton of the University of Hawaii. "They help us understand how people migrated and languages diversified not simply through isolation, but through multilingual contact."

Analyzing languages of the Dene-Yeniseian macro-family, Sicoli and Holton previously found support for Dene migrations from Beringia into North America and Yeniseian migration into Siberia. The linguists' continuing research is following up on this earlier study that posited a back-migration for the Yeniseian language family.

"In new work, Holton and I also are considering typological linguistic evidence for the subgrouping of the Dene languages suggestive of multiple routes and phases for Dene migrations in North America," Sicoli said. "We find additional support for coastal and interior distributions with two interior migration chains from Alaska into Canada and a later phase of migration involving connections between Tsuut'ina Athabaskan in western Canada and the Apache and Navajo languages of the U.S. Southwest. We also find support for a series of migrations from the Alaska and Canadian interior to the Alaska coast, which raises the question of language contact with prior languages that we are exploring with Aleut specialist Anna Berge."

In his presentation, Sicoli describes several comparisons from computational work with multiple languages from the Dene family and the more recently arriving Eskimo-Aleut family of languages. He combines geographical maps with language networks from the database that show shared features. For example, they "coded Aleut and Eskimo languages, adding them to the typological database that already included Dene languages and Haida [an isolate], and have been integrating results of phylogenetic and network analysis with prior studies of vocabulary and grammatical patterns," Sicoli writes.

"Based on linguistic analysis including computational phylogenetics," Sicoli writes, "we suggest the prehistory of South Alaska, the Aleutian Islands, and the Pacific Northwest Coast involved intensive language contacts, including language shifts from now extinct languages that we can infer through typological features, grammar and vocabulary found in languages documented in historic periods."

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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 05-Feb-2016 at 10:40

DNA evidence uncovers major upheaval in Europe near end of last Ice Age

DNA evidence lifted from the ancient bones and teeth of people who lived in Europe from the Late Pleistocene to the early Holocene -- spanning almost 30,000 years of European prehistory -- has offered some surprises, according to researchers who report their findings in the Cell Press journalCurrent Biology on Feb. 4, 2016. Perhaps most notably, the evidence shows a major shift in the population around 14,500 years ago, during a period of severe climatic instability.

"We uncovered a completely unknown chapter of human history: a major population turnover in Europe at the end of the last Ice Age," says leading author Johannes Krause of the Max Planck Institute for the Science of Human History in Germany.

The researchers pieced this missing history together by reconstructing the mitochondrial genomes of 35 hunter-gatherer individuals who lived in Italy, Germany, Belgium, France, the Czech Republic, and Romania from 35,000 to 7,000 years ago. Mitochondria are organelles within cells that carry their own DNA and can be used to infer patterns of maternal ancestry.

"There has been a real lack of genetic data from this time period, so consequently we knew very little about the population structure or dynamics of the first modern humans in Europe," Krause says.

The new data show that the mitochondrial DNA of three individuals who lived in present-day Belgium and France before the coldest period in the last Ice Age -- the Last Glacial Maximum -- belonged to haplogroup M. This is remarkable because the M haplogroup is effectively absent in modern Europeans but is extremely common in modern Asian, Australasian, and Native American populations.

The absence of the M haplogroup and its presence in other parts of the world had previously led to the argument that non-African people dispersed on multiple occasions to spread across Eurasia and Australasia. The researchers say the discovery of this maternal lineage in Europe in the ancient past now suggests instead that all non-Africans dispersed rapidly from a single population, at a time they place around 50,000 years ago. Then, at some later stage, the M haplogroup was apparently lost from Europe.

"When the Last Glacial Maximum began around 25,000 years ago, hunter-gatherer populations retreated south to a number of putative refugia, and the consequent genetic bottleneck probably resulted in the loss of this haplogroup," explains first author of the study Cosimo Posth of Germany's University of Tübingen.

The researchers say their biggest surprise, however, was evidence of a major turnover of the population in Europe around 14,500 years ago, as the climate began to warm. "Our model suggests that during this period of climatic upheaval, the descendants of the hunter-gatherers who survived through the Last Glacial Maximum were largely replaced by a population from another source," says Adam Powell, another senior author at the Max Planck Institute for the Science of Human History.

The researchers say the next step is to construct a more comprehensive picture of the past by analyzing the complete genomes of these ancient individuals along with additional specimens representing more times and places.

The researchers received support from the Baden-Württemberg Foundation, the DFG, the European Research Council, the Wenner-Gren Foundation, the College of Social and Behavioral Sciences of CSUN, and the RBINS.

http://www.sciencedaily.com/releases/2016/02/160204150602.htm

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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 13-Dec-2015 at 08:35

NYU-led research differentiates facial growth in Neanderthals and modern humans

New York University—international research team, led by Rodrigo Lacruz, PhD, assistant professor in the Department of Basic Science and Craniofacial Biology at New York University's College of Dentistry (NYUCD), has just published a study describing for the first time the developmental processes that differentiate Neanderthal facial skeletons from those of modern humans.

Lacruz's research team showed that the Neanderthals, who appeared about 200,000 years ago, are quite distinct from Homo sapiens (humans) in the manner in which their faces grow, adding to an old but important debate concerning the separation of these two groups. The paper, "Ontogeny of the Maxilla in Neanderthals and their Ancestors," appears in Nature Communications

"This is an important piece of the puzzle of evolution," says Lacruz, a paleoanthropologist and enamel biologist. "Some have thought that Neanderthals and humans should not be considered distinct branches of the human family tree. However, our findings, based upon facial growth patterns, indicate they are indeed sufficiently distinct from one another.

In conducting the research, the team set out to understand the morphological processes that distinguish Neanderthals' faces from modern humans'--a potentially important factor in understanding the process of evolution from archaic to modern humans.

Bone is formed through a process of bone deposition by osteoblasts (bone-forming cells) and resorption by osteoclast (bone-absorbing) cells, which break down bone. In humans, the outermost layer of bone in the face consists of large resorptive fields, but in Neanderthals, the opposite is true: In the outermost layer of bone, there is extensive bone deposition.

The team used an electron microscope and a portable confocal microscope, developed by co-author Dr. Timothy Bromage of NYUCD's Department of Biomaterials, himself a pioneer in the study of facial growth remodeling in fossil hominins, to map for the first time the bone-cell growth processes (resorption and deposition) that had taken place in the outer layer of the facial skeletons of young Neanderthals.

"Cellular processes relating to growth are preserved on the bones," says Bromage. "Resorption can be seen as crater-like structures--called lacunae--on the bone surface, whereas layers of osteoblast deposits have a relatively smooth appearance."

The study found that in Neanderthals, facial bone-growth remodeling--the process by which bone is deposited and reabsorbed, forming and shaping the adult skeleton--contributed to the development of a projecting (prognathic) maxilla (upper jawbone) because of extensive deposits by osteoblasts without a compensatory resorption--a process they shared with ancient hominins. This process is in stark contrast to that in human children, whose faces grow with a counter-balance action mediated by resorption taking place especially in the lower part of the face, leading to a flatter jaw relative to Neanderthals.

The team studied several well-preserved Neanderthal child skulls unearthed in 1926 in the British territory of Gibraltar and from the La Quina site in southwestern France, also excavated in the early 1900s. They also compared Neanderthal facial-growth remodeling with that of four Middle Pleistocene (about 400,000 years ago) hominin faces of teenagers from the fossil collection of the Sima de los Huesos in north-central Spain. The Sima fossils are considered likely Neanderthal ancestors based on both anatomical features and genomic DNA analysis....

http://popular-archaeology.com/issue/fall-2015/article/nyu-led-research-differentiates-facial-growth-in-neanderthals-and-modern-humans

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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 22-Jul-2015 at 12:45
A DNA Search for the First Americans Links Amazon Groups to Indigenous Australians
The new genetic analysis takes aim at the theory that just one founding group settled the Americas.

More than 15,000 years ago, humans began crossing a land bridge called Beringia that connected their native home in Eurasia to modern-day Alaska. Who knows what the journey entailed or what motivated them to leave, but once they arrived, they spread southward across the Americas

The prevailing theory is that the first Americans arrived in a single wave, and all Native American populations today descend from this one group of adventurous founders. But now there’s a kink in that theory. The latest genetic analyses back up skeletal studies suggesting that some groups in the Amazon share a common ancestor with indigenous Australians and New Guineans. The find hints at the possibility that not one but two groups migrated across these continents to give rise to the first Americans.

“Our results suggest this working model that we had is not correct. There’s another early population that founded modern Native American populations,” says study coauthor David Reich, a geneticist at Harvard University.  

The origin of the first Americans has been hotly debated for decades, and the questions of how many migratory groups crossed the land bridge, as well as how people dispersed after the crossing, continue to spark controversy. In 2008, a team studying DNA from 10,800-year-old poop concluded that a group of ancient humans in Oregon has ancestral ties to modern Native Americans. And in 2014, genetic analysis linked a 12,000-year-old skeleton found in an underwater cave in Mexico to modern Native Americans.

Genetic studies have since connected both these ancient and modern humans to ancestral populations in Eurasia, adding to the case that a single migratory surge produced the first human settlers in the Americas. Aleutian Islanders are a notable exception. They descend from a smaller second influx of Eurasians 6,000 years ago that bear a stronger resemblance to modern populations, and some Canadian tribes have been linked to a third wave.

Reich’s group had also previously found genetic evidence for a single founding migration. But while sifting through genomes from cultures in Central and South America, Pontus Skoglund, a researcher in Reich’s lab, noticed that the Suruí and Karitiana people of the Amazon had stronger ties to indigenous groups in Australasia—Australians, New Guineans and Andaman Islanders—than to Eurasians.

Other analyses haven’t looked at Amazonian populations in depth, and genetic samples are hard to come by. So the Harvard lab teamed up with researchers in Brazil to collect more samples from Amazonian groups to investigate the matter. Together they scrutinized the genomes of 30 Native American groups in Central and South America. Using four statistical strategies, they compared the genomes to each other and to those of 197 populations from around the world. The signal persisted. Three Amazonian groups—Suruí, Karitiana and Xavante—all had more in common with Australasians than any group in Siberia.

Researchers mapped similarities in genes, mutations and random pieces of DNA of Central and South American tribes with other groups. Warmer colors indicate the strongest affinities. (Pontus Skoglund, Harvard Medical School)

The DNA that links these groups had to come from somewhere. Because the groups have about as much in common with Australians as they do with New Guineans, the researchers think that they all share a common ancestor that lived tens of thousands of years ago in Asia but that doesn’t otherwise persist today. One branch of this family tree moved north to Siberia, while the other spread south to New Guinea and Australia. The northern branch likely migrated across the land bridge in a separate surge from the Eurasian founders. The researchers have dubbed this hypothetical second group “Population y” for ypykuéra, or “ancestor” in Tupi, a language spoken by the Suruí and Karitiana.

When exactly Population y arrived in the Americans remains unclear—before, after or simultaneously with the first wave of Eurasians are all possibilities. Reich and his colleagues suspect the line is fairly old, and at some point along the way, Population y probably mixed with the lineage of Eurasian settlers. Amazonian tribes remain isolated from many other South American groups, so that’s probably why the signal remains strong in their DNA.  

The results line up with studies of ancient skulls unearthed in Brazil and Colombia that bear stronger resemblance to those of Australasians than the skulls of other Native Americans. Based on the skeletal remains, some anthropologists had previously pointed to more than one founding group, but others had brushed off the similarities as a byproduct of these groups living and working in similar environments. Bones can only be measured and interpreted so many ways, while genes usually make a more concrete case.

“The problem so far was that there has never been strong genetic evidence to support this notion,” says Mark Hubbe, an anthropologist at Ohio State University who was not affiliated with the latest study.

But even genetic evidence is subject to skepticism and scrutiny. Cecil Lewis Jr., an anthropological geneticist at the University of Oklahoma, cautions that Amazonian groups are low on genetic diversity and are more susceptible to genetic drift. “This raises very serious questions about the role of chance … in creating this Australasian affinity,” he says.

Another group led by Eske Willerslev and Maanasa Raghavan at the University if Copenhagen reports in Science today that Native Americans descend from just one line that crossed the land bridge no earlier than 23,000 years ago. While they didn’t look at Amazonian groups in-depth, the team did find a weak link between Australasians and some South American populations, which they chalk up to gene flow from Eskimos. 

There’s just one problem: Evidence of Population y doesn’t persist in modern Eurasian groups, nor does it seem to show up in other Native Americans. If Aleutian Islanders or their ancestors had somehow mixed with an Australasian group up north or made their way south to the Amazon, they'd leave genetic clues along the way. “It’s not a clear alternative,” argues Reich. 

Both studies therefore suggest that the ancestry of the first Americans is a lot more complicated than scientists had envisioned. “There is a greater diversity of Native American founding populations than previously thought,” says Skoglund. “And these founding populations connect indigenous groups in far apart places of the world.”

http://www.smithsonianmag.com/science-nature/dna-search-first-americans-links-amazon-indigenous-australians-180955976/?utm_source=facebook.com&no-ist



Edited by TheAlaniDragonRising - 22-Jul-2015 at 12:52
What a handsome figure of a dragon. No wonder I fall madly in love with the Alani Dragon now, the avatar, it's a gorgeous dragon picture.
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  Quote red clay Quote  Post ReplyReply Direct Link To This Post Posted: 17-Jul-2015 at 09:22
I don't know why we are always surprised by findings such as this. Humans are problem solvers. Missing a body part such as a toe or leg etc. is a problem, replace it with something else, problem solved.

What I find amazing is the fact that Romans were doing cataract removal [Eye surgery] BCE.
"Arguing with someone who hates you or your ideas, is like playing chess with a pigeon. No matter what move you make, your opponent will walk all over the board and scramble the pieces".
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  Quote Don Quixote Quote  Post ReplyReply Direct Link To This Post Posted: 16-Jul-2015 at 14:25
Prosthetics in Ancient Egypt? The picture shows they did a good job.

"...Egyptians appear to have taken great pains to have the bodies of their dead buried intact. Some mummified remains are found with makeshift limbs and false eyes to replace missing parts. This artificial toe, attached to the right foot of a priest's daughter, is so well made, however, it's unlikely it was only intended to prepare her for the afterlife.

The dense hardwood used in the toe's construction is robust enough to withstand bodily forces—while walking, a big toe must bear up to 40 percent of a person's body weight. It also has a beveled edge at its attachment point, indicating it was deliberately designed to maximize comfort, says Jacqueline Finch, a visiting scientist at the University of Manchester's KNH Centre for Biomedical Egyptology. She recruited two volunteers who are missing their right big toes to wear a reproduction of this device along with replica Egyptian sandals. Both reported that it was comfortable and assisted them in walking.

Until now, an artificial leg made of bronze and wood and found buried with a Roman aristocrat in southern Italy dating to 300 B.C. was thought to be the first prosthesis. Finch's work suggests, however, that the Egyptians be credited with pioneering prosthetic medicine..."
http://archive.archaeology.org/1105/artifact/egyptian_mummy_artificial_toe.html
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  Quote Don Quixote Quote  Post ReplyReply Direct Link To This Post Posted: 25-Jun-2015 at 21:02
"...Indigenous people that lived in southeastern Brazil in the late 1800s shared some genetic sequences with Polynesians, an analysis of their remains shows. The finding offers some support for the possibility that Pacific islanders traded with South America thousands of years ago, but researchers say that the distinctive DNA sequences, or haplogroups, may have entered the genomes of the native Brazilians through the slave trade during the nineteenth century...."
http://www.nature.com/news/dna-study-links-indigenous-brazilians-to-polynesians-1.12710?utm_content=buffer31410&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer

I wasn't aware that Polynesians were enslaved together with people from West Africa. It seems to me that the genetic connection would be older, via some Polynesian crossings of the Pacific...Kon Tiki and so on.
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  Quote Don Quixote Quote  Post ReplyReply Direct Link To This Post Posted: 21-Apr-2015 at 16:06
Medieval medicines, according to this article weren't only mumbo-jumbo - most of the recipes cited in this article show mixtures of quite useful herbs; of course, I would avoid adding cormorant blood, bull gall and the patient urine to the potions...

"....Supposedly invented by St Paul, this potion was to be drunk. The extensive list of ingredients included liquorice, sage, willow, roses, fennel, cinnamon, ginger, cloves, cormorant blood, mandrake, dragon’s blood and three kinds of pepper.Although this sounds like a real witch’s brew, most of the ingredients do have some medicinal value: liquorice is good for the chest – it was and continues to be used to treat coughs and bronchitis; sage is thought to improve blood flow to the brain and help one’s memory, and willow contains salicylic acid, a component of aspirin. Fennel, cinnamon and ginger are all carminatives (which relieve gas in the intestines), and would relieve a colicky stomach...."

http://www.historyextra.com/article/medieval/9-weird-medieval-medicines?utm_source=Facebook+referral&utm_medium=Facebook.com&utm_campaign=Bitly

Edited by Don Quixote - 21-Apr-2015 at 16:07
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  Quote Don Quixote Quote  Post ReplyReply Direct Link To This Post Posted: 24-Mar-2015 at 14:29
Public Buildings or Maya Society - which came first? Kind of like the old saying about the hen and the egg...

"(Takeshi Inomata)
TUCSON, ARIZONA—Excavations at the Maya site of Ceibal in Guatemala have revealed a public plaza that dates to about 950 B.C., and ceremonial buildings surrounding the plaza that grew to monumental sizes by about 800 B.C. Yet there is little evidence of permanent residential dwellings in the area during the same time period. “Our study presents the first relatively concrete evidence that mobile and sedentary people came together to build a ceremonial center,” Takeshi Inomata of the University of Arizona said in a press release. Most people at this time were living a traditional hunter-gatherer lifestyle, moving throughout the rainforest. These different groups of people may have come together at Ceibal to construct the buildings and to participate in public ceremonies over a period of several hundred years before making the transition to a fully sedentary society. “This tells us something about the importance of ritual and construction. People tend to think that you have a developed society and then building comes. I think in many cases it’s the other way around,” Inomata explained."
http://www.archaeology.org/news/3112-150324-maya-melting-pot
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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 20-Mar-2015 at 22:59

East African Fossil Finds Show Early Human Diversity

Modern scholarship on human evolution has generally accepted the suggestion that there were some key changes in the skeletal anatomy of early humans sometime between the two genuses,Australopithecus, and Homo. Australopithecus, the proto-human thought to be ancestral to the more direct human line of Homo, is considered to have featured more primitive, ape-like characteristics.Homo, by contrasthas been thought to feature new, derived characteristics approaching the morphology more typically associated with human-like physical traits. 

But given the relative scarcity of early Homo fossil remains, comparatively less is known about the earliest Homo postcranial morphologies. A recent study by an international team ofHomo fossil remains uncovered in Kenya, however, has provided a few more clues reflecting on the diversity and complexity of early Homo differentiation during the earliest periods of the emergence of humans from the still obscure primordial mix of a time when some species of Australopithecus are thought to have coexisted with their 'more advanced' Homo counterparts. The team examined a partial ilium (the uppermost and largest bone of thepelvis), and a femur (thigh bone) found at the famous hominin fossil site of Koobi Fora, Kenya, dating to 1.9 Ma (millions of years ago). They found that the specimens featured attributes commonly associated with the genus Homo. But they also found morphological characteristics not typically seen in eastern African early Homo erectus fossils:  "The geometry of the femoral midshaft and contour of the pelvic inlet do not resemble that of any specimens attributed to H. erectus from eastern Africa," summarized the study authors in their report, which will soon be published in the Journal of Human Evolution. "This new fossil confirms the presence of at least two postcranial morphotypes within early Homo, and documents diversity in postcranial morphology among early Homo species that may reflect underlying body form and/or adaptive differences."*

Koobi Fora has long been known as a key region containing hominin fossils that have shed light on human evolution over the last 4.2 million years. It is described as a ridge or outcrop of Pliocene/Pleistocene sediments that preserve a prolific record of mammal fossils, including early hominin species. The ridge is being eroded into a badlands terrain by rivers draining into modern Lake Turkana. Anciently, Lake Turkana provided a good habitable lake environment for a variety of mammals, including early humans. In 1968, Richard Leakey, the son of famous paleoanthropologist Louis Leakey and Mary Leakey, established the Koobi Fora Base Campa field center for hominin studies, at Lake Turkana.

http://popular-archaeology.com/issue/spring-2015/article/east-african-fossil-find-shows-early-human-diversity

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  Quote Don Quixote Quote  Post ReplyReply Direct Link To This Post Posted: 05-Jan-2015 at 17:48
Amulet for protection of evil with the image of a god on it from 6 cent. AD has been found in Cyprus. At this time Cyrpus was s apart of the Byzantine/Eastern Roman Empire, with Chrsitianity as official religion. However, the god/s presented and mentioned on the amulet are Ra and Harpocrates, a Greek god of science.
http://www.archaeology.org/news/2867-150105-cyprus-palindrome-amulet-unearthed

In time Christianity adopted the idea of such amulets, and in Bulgaria small amulets with the images of Christ or saints, made to be worn around the neck for protection, are still sold.

Edited by Don Quixote - 05-Jan-2015 at 17:51
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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 01-Jan-2015 at 06:36

Hunter-gatherer past shows our fragile bones result from inactivity since invention of farming

New research across thousands of years of human evolution shows that our skeletons have become much lighter and more fragile since the invention of agriculture -- a result of our increasingly sedentary lifestyles as we shifted from foraging to farming.
The new study, published today in the journal PNAS, shows that, while human hunter-gatherers from around 7,000 years ago had bones comparable in strength to modern orangutans, farmers from the same area over 6,000 years later had significantly lighter and weaker bones that would have been more susceptible to breaking.

Bone mass was around 20% higher in the foragers -- the equivalent to what an average person would lose after three months of weightlessness in space.

After ruling out diet differences and changes in body size as possible causes, researchers have concluded that reductions in physical activity are the root cause of degradation in human bone strength across millennia. It is a trend that is reaching dangerous levels, they say, as people do less with their bodies today than ever before.

Researchers believe the findings support the idea that exercise rather than diet is the key to preventing heightened fracture risk and conditions such as osteoporosis in later life: more exercise in early life results in a higher peak of bone strength around the age of 30, meaning the inevitable weakening of bones with age is less detrimental.

There is, in fact, no anatomical reason why a person born today could not achieve the bone strength of an orangutan or early human forager, say researchers; but even the most physically active people alive are unlikely to be loading bones with enough frequent and intense stress to allow for the increased bone strength seen in the 'peak point' of traditional hunter-gatherers and non-human primate bones.

"Contemporary humans live in a cultural and technological milieu incompatible with our evolutionary adaptations. There's seven million years of hominid evolution geared towards action and physical activity for survival, but it's only in the last say 50 to 100 years that we've been so sedentary -- dangerously so," said co-author Dr Colin Shaw from the University of Cambridge's Phenotypic Adaptability, Variation and Evolution (PAVE) Research Group.

"Sitting in a car or in front of a desk is not what we have evolved to do."

The researchers x-rayed samples of human femur bones from the archaeological record, along with femora from other primate species, focusing on the inside of the femoral head: the ball at the top of the femur which fits into the pelvis to form the hip joint, one of the most load-bearing bone connections in the body.

Two types of tissue form bone: the cortical or 'hard' bone shell coating the outside, and the trabecular or 'spongy' bone: the honeycomb-like mesh encased within cortical shell that allows flexibility but is also vulnerable to fracture.

The researchers analysed the trabecular bone from the femoral head of four distinct archaeological human populations representing mobile hunter-gatherers and sedentary agriculturalists, all found in the same area of the US state of Illinois (and likely to be genetically similar as a consequence).

The trabecular structure is very similar in all populations, with one notable exception: within the mesh, hunter-gatherers have a much higher amount of actual bone relative to air.

"Trabecular bone has much greater plasticity than other bone, changing shape and direction depending on the loads imposed on it; it can change structure from being pin or rod-like to much thicker, almost plate-like. In the hunter-gatherer bones, everything was thickened," said Shaw.

This thickening is the result of constant loading on the bone from physical activity as hunter-gatherers roamed the landscape seeking sustenance. This fierce exertion would result in minor damage that caused the bone mesh to grow back ever stronger and thicker throughout life -- building to a 'peak point' of bone strength which counter-balanced the deterioration of bones with age.

Shaw believes there are valuable lessons to be learnt from the skeletons of our prehistoric predecessors. "You can absolutely morph even your bones so that they deal with stress and strain more effectively. Hip fractures, for example, don't have to happen simply because you get older if you build your bone strength up earlier in life, so that as you age it never drops below that level where fractures can easily occur."

Other theories for humans evolving a lighter, more fragile skeleton include changes in diet or selection for a more efficient, lighter skeleton, which was never reversed.

While the initial switch to farming did cause a dip in human health due to monoculture diets that lacked variety, the populations tested were unaffected by this window in history. "Of course we need a level of calcium to maintain bone heath, but beyond that level excess calcium isn't necessary," said Shaw.

The research also counters the theory that, at some point in human evolution, our bones just became lighter -- perhaps because there wasn't enough food to support a denser skeleton. "If that was true, human skeletons would be entirely distinct from other living primates. We've shown that hunter-gatherers fall right in line with primates of a similar body size. Modern human skeletons are not systemically fragile; we are not constrained by our anatomy."

"The fact is, we're human, we can be as strong as an orangutan -- we're just not, because we are not challenging our bones with enough loading, predisposing us to have weaker bones so that, as we age, situations arise where bones are breaking when, previously, they would not have" Shaw said.

While the 7,000-year-old foragers had vastly stronger bones than the 700-year-old farmers, Shaw says that neither competes with even earlier hominids from around 150,000 years ago. "Something is going on in the distant past to create bone strength that outguns anything in the last 10,000 years."

The next step for Shaw's research team will be to look at how different types of loading and mobility shape bodies and bones by cross-referencing archaeological records with testing on modern ultra-marathon runners, who cover punishing distances over a range of terrains -- from the Himalayas to the Namibian desert. He hopes this future work will provide insight into the kind of mobility that gave our ancient ancestors such powerful physical strength.

http://www.sciencedaily.com/releases/2014/12/141222165033.htm

What a handsome figure of a dragon. No wonder I fall madly in love with the Alani Dragon now, the avatar, it's a gorgeous dragon picture.
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  Quote Don Quixote Quote  Post ReplyReply Direct Link To This Post Posted: 09-Dec-2014 at 19:41
Check it out! The Vikings were taking their girlfriend to a trip to Scotland and the Orkneys, instead of only relying on seducing of local maids :).
"...OSLO, NORWAY—Analysis of mitochondrial DNA obtained from 80 Viking skeletons in Norway suggests that Norse women participated in the colonization of the Scottish mainland, Shetland, Orkney, and Iceland 1,000 years ago. Mitochondrial DNA is only inherited through the female line. “It seems to support the view that a significant number of women were involved in the settlement of the smaller isles, which overrules the idea that it just involved raping and pillaging by males going out on a rampage,” Erika Hagelberg of the University of Oslo told The Independent. ..."
http://www.archaeology.org/news/2763-141208-norway-viking-women
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  Quote Don Quixote Quote  Post ReplyReply Direct Link To This Post Posted: 30-Aug-2014 at 16:54
How long ago was the toilet seat invented? It may not look like some heroic invention, but my body is definitely happy that someone had thought about it.

"...NORTHUMBERLAND, ENGLAND—A 2,000-year-old wooden toilet seat has been discovered in a muddy garbage trench at Vindolanda, a Roman fort located at Hadrian’s Wall...."
http://www.archaeology.org/news/2472-140828-england-vindolanda-seat
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  Quote TheAlaniDragonRising Quote  Post ReplyReply Direct Link To This Post Posted: 01-Aug-2014 at 23:13

Society bloomed with gentler personalities and more feminine faces: Technology boom 50,000 years ago correlated with less testosterone

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.

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.

What they can't tell from the bones is whether these humans had less testosterone in circulation, or fewer receptors for the hormone.

The research team also included Duke animal cognition researchers Brian Hare and Jingzhi Tan, who say this argument is in line with what has been established in non-human species.

In a classic study of Siberian foxes, animals that were less wary and less aggressive toward humans took on a different, more juvenile appearance and behavior after several generations of selective breeding.

"If we're seeing a process that leads to these changes in other animals, it might help explain who we are and how we got to be this way," said Hare, who also studies differences between our closest ape relatives -- aggressive chimpanzees and mellow, free-loving bonobos.

Those two apes develop differently, Hare said, and they respond to social stress differently. Chimpanzee males experience a strong rise in testosterone during puberty, but bonobos do not. When stressed, the bonobos don't produce more testosterone, as chimps do, but they do produce more cortisol, the stress hormone.

Their social interactions are profoundly different and, relevant to this finding, their faces are different, too. "It's very hard to find a brow-ridge in a bonobo," Hare said.

Cieri compared the brow ridge, facial shape and interior volume of 13 modern human skulls older than 80,000 years, 41 skulls from 10,000 to 38,000 years ago, and a global sample of 1,367 20th century skulls from 30 different ethnic populations.

The trend that emerged was toward a reduction in the brow ridge and a shortening of the upper face, traits which generally reflect a reduction in the action of testosterone.

There are a lot of theories about why, after 150,000 years of existence, humans suddenly leapt forward in technology. Around 50,000 years ago, there is widespread evidence of producing bone and antler tools, heat-treated and flaked flint, projectile weapons, grindstones, fishing and birding equipment and a command of fire. Was this driven by a brain mutation, cooked foods, the advent of language or just population density?

The Duke study argues that living together and cooperating put a premium on agreeableness and lowered aggression and that, in turn, led to changed faces and more cultural exchange.

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

http://www.sciencedaily.com/releases/2014/08/140801171114.htm

What a handsome figure of a dragon. No wonder I fall madly in love with the Alani Dragon now, the avatar, it's a gorgeous dragon picture.
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