Monday, April 30, 2018

DNA adds twist to ancient story of a Native American group

The ancient genomes of the Tsimshian indigenous people left tell-tale markers on the trail of their past, revealing that at least 6,000 years ago their population size was on a slow but steady decline.

The American Journal of Human Genetics published the findings, which draw from the first population-level nuclear DNA analysis of a Native American group from ancient to modern times.

"The finding contradicts a popular notion," says John Lindo, a geneticist in Emory University's Department of Anthropology and first author on the paper. "There is this idea that after Native Americans came in through the Bering Strait that they were all expanding in population size until Europeans showed up. At least for this one population, we've shown that was not the case."

A boon in next-generation DNA sequencing technology has opened the possibility to explore the evolutionary history of different populations. "Ancient nuclear DNA analysis is a relatively new field," Lindo says. "Not until recently have we had methods to sequence an entire genome quickly and inexpensively."

Nuclear DNA provides information on an individual's lineages going back hundreds of thousands of years. Lindo is one of the few geneticists looking at ancient whole genomes of Native Americans. He is especially interested in understanding how the genomes of their different populations evolved over time.

"Their evolutionary histories are radically different," Lindo says. "Over thousands of years, various Native American populations have adapted to living in every ecology throughout North and South America, from the Arctic to the Amazon. That's about as an extreme as you can get for differences in environments."

The Tsimshian people historically lived in longhouses in coastal British Columbia and southern Alaska where they harvested the abundant sea life. Lindo and his colleagues sequenced the genomes of 25 living Tsimshian people and 25 ancient individuals who lived in the same region between 6,000 and 500 years ago, and confirmed that they were a continuous population through time.

In a previous paper, drawing from the same data set, they found a dramatic shift between the two time periods in a class of genes associated with the immune system, suggesting a strong evolutionary pressure on the population to adapt to pathogens. A demographic model indicated a crash in the Tsimshian population size of about 57 percent during the early-to-mid 19th century. That finding fitted with historical accounts for how smallpox, introduced by European colonization, devastated the Tsimshian population during two epidemics within that timeframe.

The current paper looked at broader genetic variations between the ancient and modern DNA. An analysis showed both how the variation declined slowly in the ancient population before the collapse, but has since recovered.

"After a population collapse, only a subset of the genetic diversity remains," Lindo says. "We find a more nuanced story, that despite the population collapse, the genetic diversity of modern Tsimshian people varies significantly."

Intermarriage with other Native American groups and non-native populations increased the genetic diversity of some of the modern-day Tsimshian people so that it is near the levels prior to their population collapse, the analysis showed.

"A population with relatively high genetic diversity has a greater potential to fight off pathogens and avoid recessive traits," Lindo says. "It exemplifies the benefits of gene flow between populations, especially following catastrophic events such as the small pox epidemics that the Tsimshian endured."

Senior authors on the paper are Michael DeGiorgio from Pennsylvania State University and Ripan Malhi from the University of Illinois. The paper's coauthors include Tsimshian representatives Joycelynn Mitchell and Barbara Petzelt from the Metlakatla Treaty Office in Prince Rupert, Canada.
Malhi, a leader in forging trusting relationships between genetic researchers and indigenous people, was a mentor to Lindo, who earned his PhD at the University of Illinois at Champaign-Urbana.
Lindo is continuing that tradition of building trust and working closely with indigenous populations. His ancient DNA research at Emory integrates the approaches of ancient whole genomes, statistical modeling and functional methods.

One of his projects is focused on genetic fluctuations to help understand ancient adaptions in various Native American populations. He is currently working with 10 different tribes from throughout North America.

"Community engagement is essential when working with indigenous communities," says Lindo, explaining that he first meets personally with a tribal community to talk about how a genetic study might add to their knowledge of their own history.

"I listen to their stories and how they are working to keep their cultures alive," he says. "One elder from a southwestern tribe told me that his grandfather was taken away in the early 1900s because he was a shaman and Christianity was swelling through the area. Each tribe's stories are different but they are all powerful, and sometimes difficult, stories to hear."

Most ancient DNA analyses have come out of Europe, where more ancient DNA labs are based and cold temperatures have helped preserve specimens.

Lindo wants to bring some of the same insights that those of European ancestry are gaining about their past to Native Americans.

"I'd like to disentangle this idea that Native Americans are part of a singular race," he says. "I want to help Native American tribes to reclaim knowledge of their very ancient evolutionary histories -- histories that have been largely wiped away because of colonialism."

Saturday, April 28, 2018

Study sheds light on recently evolved traits among Japanese descendants

Osaka University

IMAGE: Genetic loci with strong recent selection pressure in the Japanese population. view more 
Credit: Osaka University
Osaka - Evolution enables beneficial traits to dominate a population. Given enough time, groups exposed to different environments will eventually evolve unique adaptive traits. Knowing how environmental pressures shape human evolution can lead to a better understanding of why certain populations or ethnic groups today are predisposed to certain characteristics. In a new study published in Nature Communications, researchers centered at Osaka University conducted a large-scale genomic analysis to explore recent evolutionary events among individuals of Japanese descent.
The team performed whole-genome sequencing using 2,234 Japanese participants. As its name suggest, the technique attempts to read the entirety of a genome--all three billion letters of it. Comparing the genomes of many individuals at once makes it possible to find regions that have changed more rapidly than others--in other words, places where evolution has caused a particular genetic trait to predominate.
Not all genome sequencing studies are created equal; however, with some doing a better job of reading genomes than others.
"Whole-genome sequencing is a common technique, but our analysis achieved exceptionally 'deep' sequencing," lead author Yukinori Okada explains. "This means that we collected significantly more information from each person's genome compared with similar studies. This allowed us to identify evolutionary changes that occurred over much more recent periods of time, on the scale of the last 2,000 to 3,000 years."
Previous studies looking at similar time scales have focused exclusively on European ancestry. In those studies, it was found that Europeans mostly experienced adaptations related to height, obesity, and the immune system. The current study supplements these findings by focusing on Japanese individuals--from an area where evolutionary pressures have had a distinct impact on adaptive traits.
"Our study is the largest high-depth sequencing study conducted to date on a non-European population," contributing author Saori Sakaue adds. "We found that very different evolutionary traits have evolved in Japanese populations over the last few thousand years, particularly traits involved in the metabolism of alcohol, glucose, and lipids. Given the clear evolutionary differences between European and Japanese populations, we expect our findings to shed light on how different ancestries can evolve divergent traits over very short periods of time."

Palmyra: Loss and Remembrance

Palmyra: Loss and Remembrance
Getty Villa. LOS ANGELES
April 18, 2018 – May 27, 2019

The ancient city of Palmyra (“Place of Palms”), well situated in an oasis in the Syrian desert, flourished between the first and third centuries AD. At the crossroads of trade routes between the Roman and Parthian Persian empires, the people of Palmyra embellished their tombs with distinctive funerary portraits that illuminate the rich cultural exchanges and interactions taking place throughout the eastern Mediterranean and Near East. 

Head of a Man, AD 190-210. Palmyran Limestone. H: 34 x W: 26.5 x D: 33 cm (13 3/8 x 10 7/16 x 13 in.) Ny Carlsberg Glyptotek, Copenhagen IN1145 VEX.2018.3.1

Palmyra: Loss and Remembrance , on display as a long- term loan at the Getty Villa from April 18, 2018 through May 27, 2019, presents a selection of the finest surviving Palmyran funerary portrait sculptures from the unrivalled collection of the Ny Carlsberg Glyptotek in Copenhagen. 

The exhibition will also include historical engravings and photographs from the Getty Research Institute that represent the earliest photographic record of this unique archaeological site. As part of the reinstallation of the antiquities collection at the Getty Villa, this exhibition will be the first display in a new gallery dedicated to “The Classical World in Context,” which will present long- term loans of objects from cultures that engaged and interacted with the ancient classical cultures of Greece and Italy. 

“Control of the Near Eastern lands conquered by Alexander the Great in the 320s BC gradually shrank back to Syria and the eastern littoral of the Mediterranean, where it remained into the first centuries of the Roman Empire. But the influence of Greek and Roman art in the further reaches of Alexander’s conquests lingered m uch longer , and we see remarkable efflorescences of classicizing sculpture in the first centuries AD in Parthia ( Mesopotamia and Persia), Gandhara (Pakistan), and , closer to the Mediterranean, at Petra and Palmyra,” says Timothy Potts, director of the J. Paul Getty Museum. “The remarkable works of art from the latter site are the most vivid artistic evidence of a cosmopolitan, polyg lot, and multicultural world that flourished in the first centuries of the Christian era . Sadly, much of this extraordinary artistic heritage has been the subject of horrendous vandalism in recent years —which makes those works that survive even more precious .” 

The people of the ancient city of Palmyra grew rich transporting silk, spices, gems, and other commodities, as well as slaves, by caravan to the Mediterranean from Persia, India, and as far east as China. Grand temples, colonnaded streets, and richly decorated communal tombs attest to Palmyra’s period of great prosperity. Ornamented tombs contained expressive likenesses of men, women, and children accompanied by inscriptions naming the deceased. 

Details of their dress, jewelry, and other attributes reveal the city’s distinctive cultural mix of Greek, Roman, and Parthian (ancient Iranian) culture . Inspired by their Greek and Roman neighbors, Palmyrans made and publicly displayed portraits honoring the deeds of important citizens. Most surviving sculpture from the site, however, consists of funerary portraits commemorating the dead. 

Reliefs carved from local limestone and then brightly painted were arranged in rows within monumental tombs. They were used to seal loculi (individual burial niches) within towers, hypogea (underground chambers) , and mausolea (temple- like structures ) where hundreds were buried in vast galleries of multi- generational family portraits . 

Most reliefs bear inscriptions in Palmyr an Aramaic express ing grief for the loss of the deceased, naming family members, and, in some cases, provid ing lengthy genealogies. 

The Palmyran custom was to depict the deceased finely clothed and gazing forward. Men usually appear in tunics and Greek -style cloaks; their professions are rarely indicated, though priestly status is noted. In early reliefs, women hold a distaff and spindle for spinning wool —traditional symbols of female virtue. With time, female portraits included rich displays of jewelry and changing hairstyles, likely reflecting the increasing wealth, growing trade connections, and evolving fashions of the city. 

Although Palmyran reliefs usually present their subjects with generic features and neutral expressions, they nonetheless reveal deliberate and individualized choices. Those who commissioned and carved the portraits selected from a repertoire of hairstyles, clothing, gestures, jewelry, and other meaningful attributes. In commemorating the dead, they sometimes also included representations of other family members. Palmyran portraits —while less naturalistic than Roman sculptures of the time—embody familial aspirations and communal values as well as personal emblems of those they represent. 

“These vivid personal portraits bring the viewer face- to-face with ancient individuals and their families, expressing their values and reflecting developing social trends,” says Kenneth Lapati , curator of the exhibition. “At the same time, they convey ancient cosmopolitanism and connections between diverse cultures.” 

Designated a UNESCO World Heritage site in 1980, the ancient buildings of Palmyra have inspired Western artists and architects s ince the late 1600s. Though the monuments of Palmyra survived for millennia, the site has suffered greatly in the current Syrian civil war, which has resulted in thousands of deaths and the deliberate destruction of buildings and artifacts. 

Recently acquired by the Getty Research Institute and on view for the first time, are well - preserved photographs of the site taken in 1864 by Louis Vignes, a French naval officer who was trained in photography by the renowned photographer Charles Nègre. The earliest photographic record of the site, these photographs include unique views and panoramas of Palmyra’s Roman ruins, some of which are now destroyed. 

Man with Camel, about AD 160
Object: H: 56.5 x W: 54.5 x D: 10 cm (22 1/4 x 21 7/16 x
3 15/16 in.)
Ny Carlsberg Glyptotek, Copenhagen IN2883


Male and His Sons (?) AD 192–210
Palymran Limestone
Object: H: 60 x W: 36 x D: 19.5 cm (23 5/8 x 14 3/16 x 7 11/16 in.)
Cantor Arts Center at Stanford University, Stanford Family
Collections, Palo Alto JLS.17200 (left), Ny Carlsberg Glyptotek,
Copenhagen IN2775 (right)
Another highlight of the exhibition is a double relief of a father and son, which was broken in half and sold separately sometime before 1880, and will be reunited in the exhibition for the first time . 

In 1880, Leland Stanford Jr. purchased one half in Rome . Today, it is in the collection of the Iris & B. Gerald Cantor Center for Visual Arts at Stanford University. In 1929, the Ny Carlsberg Glyptotek acquired the other half from a collector in Beirut. In 2012, former Getty scholar Fred Albertson recognized that part of the younger man’s shoulder, as well as the branch that supports the dorsalium (funerary curtain) behind him, is preserved on the slab 4 depicting the older man. The s imilar carving of the faces, drapery, and inscriptions confirm ed that the two pieces belong together. 

Palmyra: Loss and Remembrance is curated by Kenneth Lapatin, curat or of antiquities at the J. Paul Getty Museum in collaboration with Rubina Raja, director of the Palmyra Portrait Project and professor of classical art and a rchaeology at Aarhus University , and Anne Marie Nielsen , curator of Greek and Roman art at the Ny Carlsberg Glyptotek.

Identifying the use of tinder fungi among neolithic communities at la Draga

The use of fungi to light or transport fire at la Draga some 7,300 years ago is one of the oldest examples documented until now of the technological use of these organisms
Universitat Autonoma de Barcelona
IMAGE: Sample of Ganoderma adspersum with signs of carbonization. view more 
Credit: la Draga team
Inhabitants of the Neolithic community at la Draga (Banyoles, Girona) already used fungi to light or transport fires 7300 years ago. The discovery represents one of the oldest examples of technological use of fungi documented until now and is the result of several archaeological interventions at the site, which have also yielded an exceptional collection of these organisms, unique in all of prehistoric Europe.
The study of this atypical set of remains, published recently in the journal PLOS ONE, was conducted by Marian Berihuete-Azorín (Hohenheim University), Josep Girbal (UAB), Raquel Piqué (UAB), Antoni Palomo (Museum of Archaeology of Catalonia) and Xavier Terradas (CSIC-IMF).

"Despite the use of fire being well documented, at the la Draga site we had not yet found proof of the materials used to light or transport it. Data gathered points to the majority of fungi recovered were selected, taken to the forest surrounding the site, dried and stored, with the intention of using them as tinder. In addition, it was evident in two of the samples we analysed that they were being used for this purpose, which proved our hypothesis", explains Raquel Piqué, researcher at the UAB Department of Prehistory.

The site of la Draga is one of the exceptional examples for the study of archaeological remains, which remain under the phreatic level, and this has allowed researchers to recover up to 86 different individuals, some of them complete, and conduct a taxonomic study which allowed to verify the presence of six fungi species: Skeletocutis nivea, Coriolopsis gallica, Daedalea quercina, Daldinia concentrica, Ganoderma adspersum and Lenzites warnieri.

"Being able to recover these remains is extraordinary, given that their conservation as archaeological material is very difficult due to their easiness to decompose", adds Antoni Palomo, research at the MAC and the UAB.

The majority of fungi recovered at la Draga are polypore and can both grow on dead tree trunks and parasitise living trees. They are non-edible species which have been traditionally used to light fires, and are therefore known as "tinder-fungi". Their woody structure makes them high inflammable and therefore ideal for starting and transporting fire. Among the species used for this purpose there are Daedalea quercina, different kinds of Ganoderma, Coriolopsis gallica and Daldinia concentrica, all of them documented at la Draga.

Tinder fungi was used to catch the sparks produced by hitting a siliceous rock against a mineral rich in ferric sulphide such as pyrite or marcasite. Researchers assure that the discovery makes La Draga an exceptional example for the study of fungi during Prehistory. It is one of the archaeological sites with a higher variety of fungi that has been retrieved till date.

Until now, the few archaeological discoveries of fungi belonged to sites in northern and central Europe, and only in a few cases was it possible to demonstrate technological uses. One of the most important was at the Mesolithic site of Starr Carr in England, in which samples were also interpreted as having been intentionally transported in order to be used as tinder fungi. Another notable example, but chronologically more recent than La Draga, are the remains transported by the iceman Ötzi as part of his equipment.

Importance of the Neolithic Site of la Draga
The remains studied form part a set of discoveries made at the Neolithic site of la Draga, located at the eastern shore of Lake Banyoles. The importance of this prehistoric settlement lies in the fact that it is one of the first enclaves where Neolithic farming societies decided to settle in the northeast of the Iberian Peninsula, about 7300 years ago, transforming the surroundings in order to carry out the agricultural and livestock practices necessary for their subsistence. The most outstanding feature at the site is the conservation of elements built with wood and other organic materials, an exceptional feat for such an early society and which contributes to a more complete comprehension of these first farming societies of the westernmost Mediterranean.

The site was discovered in 1990 and since then, different interventions have been carried out under the coordination of the Archaeological Museum of Banyoles and the participation of the Universitat Autònoma de Barcelona, the Spanish National Research Council (IMF, Barcelona) and the Museum of Archaeology of Catalonia.

Wednesday, April 25, 2018

The equine herald of a new age

As they had for more than a decade, Stuart Tyson Smith and his colleagues were excavating a tomb in what was Upper Nubia in their years-long UC Santa Barbara-Purdue University mission to understand the history of an ancient village on the fringes of Egyptian dominance.

But rather than finding mummified human remains, they unearthed the skeleton of a horse so well-preserved it had hair on its legs. It had been covered with a burial shroud, and among the items found with it was a piece of iron that appeared to be a cheek piece from a bridle.

Smith, a professor of archaeology in UCSB's Department of Anthropology, called the find "a complete surprise. I was not expecting to find that. We had this nice pyramid tomb and we were going down the shaft expecting to find a few human burials, and there we were about half-way down the shaft and here's this horse."

The horse turned out to be much more than an unexpected oddity. In their paper "Symbolic Equids and Kushite State Formation: A Horse Burial at Tombos," in the journal Antiquity, Smith and his collaborators -- lead author Sarah Schrader, horse specialist Sandra Olsen and co-director of the expedition Michele Buzon -- argue that the horse represents a shift away from Egyptian governance and towards a Kushite rule in which the animal was embraced as central to the state's identity.

"One of the interesting things about our horse is that it foreshadows the later development where these Nubian kings are really into horses," Smith said. Indeed, when the Kushite king Piankhi put down a rebellion in northern Egypt he was said to be enraged that his horses there had been starved in his absence. "His complaint was not that they had rebelled against him, but they had mistreated his horses," he said.

 The Tombos horse was discovered in 2011, and members of the Purdue team - professor Michele Buzon and alumna Sarah Schrader - played a part in the excavation and analysis. The horse is dated to the Third Intermediate Period, 1050-728 B.C.E., and it was found more than 5 feet underground in a tomb. The horse, with some chestnut-colored fur remaining, had been buried in a funeral position with a burial shroud. 
"It was clear that the horse was an intentional burial, which was super fascinating," said Buzon, a professor of anthropology. "Remnants of fabric on the hooves indicate the presence of a burial shroud. Changes on the bones and iron pieces of a bridle suggest that the horse may have pulled a chariot. We hadn't found anything like this in our previous excavations at Tombos. Animal remains are very rare at the site."

Buzon, a bioarchaeologist, has worked with Stuart Tyson Smith, anthropology professor at the University of California, Santa Barbara, for 18 years at this site in modern-day Sudan, and both are principal investigators on the project. Buzon uses health and cultural evidence from more than 3,000-year-old burial sites to understand the lives of Nubians and Egyptians during the New Kingdom Empire. This is when Egyptians colonized the area in about 1500 B.C. to gain access to trade routes on the Nile River. Over the years, hundreds of artifacts, including pottery, tools, carvings and dishes were unearthed at this burial site for about 200 individuals.

"Finding the horse was unexpected," Schrader said. "Initially, we weren't sure if it was modern or not. But as we slowly uncovered the remains, we began to find artifacts associated with the horse, such as the scarab, the shroud and the iron cheekpiece. At that point, we realized how significant this find was. Of course, we became even more excited when the carbon-14 dates were assessed and confirmed how old the horse was."

Schrader, who graduated from Purdue in 2013 with a doctoral degree in anthropology, is an assistant professor of human osteoarchaeology at Leiden University in The Netherlands. Schrader is lead author on this article, and she helped frame this find within the context of Nubian history.

Once the archaeologists discovered the horse, Sandra Olsen, curator-in-charge at the Biodiversity Institute and Natural History Museum at the University of Kansas and a well-known ancient horse expert, was invited to Purdue to analyze the horse skeleton. Buzon coordinated the analysis between the team, and she established the chronology of the horse via radiocarbon dating.

"The horse was treated well in life, seeing as how it lived to a mature age," Schrader said. "It also was important to the people of ancient Tombos because it was buried - a rite that is usually reserved for humans. Furthermore, the fact that one of the earliest pieces of iron from Africa was found in association with the horse reiterates how special it was to the people. It is also important to assess the context of Tombos with regard to the horse - the horse is an important and rare find. The fact that it is buried at Tombos indicates that this town may have served an important function in the post-colonial Napatan Period."

Using radiocarbon testing, the Tombos horse was dated to about 950 BC, in the Third Intermediate Period, when the Kushites of Nubia took advantage of strife in Egypt to coalesce into a political, economic and military power.

The horse was buried about 100 years after the colony began to break away in 1070 BC. The burial, Smith said, was a new development in the village at the Third Cataract of the Nile. Buried in an older tomb that had been adapted for the task, the horse was laid to rest in sacred ground.

"It's gorgeous, and the bones are a nice, rich brown color that you don't see in other contemporary horse burials," Smith noted. "All the pieces are there, everything's intact. It even had some fur left on it. As a result, because of the preservation, it's one of the most complete skeletons, and best preserved, of any of these early horses that have been found in northeast Africa."

The Tombos horse, which was determined to be female, was carefully lain on its side. Close inspection of the skeleton also revealed it suffered from arthritis and degeneration associated with wearing a chariot saddle harness. Curiously, Egyptian art always depicted chariot horses as stallions.
"It makes a certain amount of sense that they would emphasize stallions in the art," Smith said, "because they're fierce in warfare and that sort of thing. But it is interesting that in reality they were using mares as well. It's just that the artwork emphasizes the stallion as the pre-eminent chariot horse."

Among the more intriguing items found with the horse was the piece of iron that Smith said radiocarbon testing dates to around 950 BC. "This is a very early date for iron," he noted. "For a long time people had thought that iron production in Nubia really didn't ramp up until about 500 BC."
Smith, who owns a horse, said he quickly recognized the artifact as a cheek piece for a bridle, and co-author Olson has since confirmed the assessment. "It's rare to find iron like that in a good context," he said, "where you can really pin the date down.

"It also counters the narrative that Nubians were backwards somehow, that anything good they got they got from Egypt," he continued. "But they seem to have been going out and seizing what they needed. They had the latest military technology in the form of iron weaponry like we found, but also these iron trappings from the horse."

Smith and Buzon have been excavating Tombos, just east of the Nile River in Sudan, since 2000. It was founded by the Egyptians as an administrative center in Nubia around 1450 BC. Their work there has unraveled what they term "cultural entanglement," the process by which colonizing powers and indigenous people influence one another and change over time.

"You can see this long, entangled history of the horse weaving its way through all these different cultures until it comes to Nubia," Smith said. "But then, horses were important in Egypt, but we have very few horse burials there. If it was a widespread practice you'd expect to see more of them."
The Nubians, who would conquer Egypt and establish the Kushite Dynasty in 728 BC, proved to be adept at adapting Egyptian practices and technology and making them their own.

"For Nubians, they really elaborated on Egyptian materials and practices in a way that you don't see in Egypt," Smith said. "That's the case with a lot of these features that Nubians were borrowing. They often take something they really like, like horses, and they make it much more elaborate, through ritualized burial, than the examples that you have in Egypt."

Tuesday, April 24, 2018

Did last ice age affect breastfeeding in Native Americans?

The critical role that breast feeding plays in infant survival may have led, during the last ice age, to a common genetic mutation in East Asians and Native Americans that also, surprisingly, affects the shape of their teeth.
The genetic mutation, which probably arose 20,000 years ago, increases the branching density of mammary ducts in the breasts, potentially providing more fat and vitamin D to infants living in the far north where the scarcity of ultraviolet radiation makes it difficult to produce vitamin D in the skin.
If the spread of this genetic mutation is, in fact, due to selection for increased mammary ductal branching, the adaptation would be the first evidence of selection on the human maternal-infant bond.
"This highlights the importance of the mother-infant relationship and how essential it has been for human survival," said Leslea Hlusko, an associate professor of integrative biology at the University of California, Berkeley.
As for the teeth, it just so happens that the gene controlling mammary duct growth also affects the shape of human incisors. Consequently, as the genetic mutation was selected for in an ancestral population living in the far north during the last Ice Age, shovel-shaped incisors became more frequent too. Shoveled incisors are common among Native Americans and northeastern Asian populations but rare in everyone else.
Hlusko and her colleagues outline the many threads of evidence supporting the idea in an article published this week in the journal Proceedings of the National Academy of Sciences.
The finding could also have implications for understanding the origins of dense breast tissue and its role in breast cancer.
For the study, Hlusko and her colleagues assessed the occurrence of shovel-shaped incisors in archeological populations in order to estimate the time and place of evolutionary selection for the trait. They found that nearly 100 percent of Native Americans prior to European colonization had shoveled incisors, as do approximately 40 percent of East Asians today.
The team then used the genetic effects that are shared with dental variation as a way to discern the evolutionary history of mammary glands because of their common developmental pathway.
"People have long thought that this shoveling pattern is so strong that there must have been evolutionary selection favoring the trait, but why would there be such strong selection on the shape of your incisors?" Hlusko said. "When you have shared genetic effects across the body, selection for one trait will result in everything else going along for the ride."
The vitamin D connection Getting enough vitamin D, which is essential for a robust immune system and proper fat regulation as well as for calcium absorption, is a big problem in northern latitudes because the sun is low on the horizon all year long and, above the Arctic Circle, doesn't shine at all for part of the year. While humans at lower latitudes can get nearly all the vitamin D they need through exposure of the skin to ultraviolet light, the scarce UV at high latitudes forced northern peoples like the Siberians and Inuit to get their vitamin D from animal fat, hunting large herbivores and sea mammals.
But babies must get their vitamin D from mother's milk, and Hlusko posits that the increased mammary duct branching may have been a way of delivering more vitamin D and the fat that goes with it.
Hlusko, who specializes in the evolution of teeth among animals, in particular primates and early humans, discovered these connections after being asked to participate in a scientific session on the dispersal of modern humans throughout the Americas at the February 2017 American Association for the Advancement of Science meeting. In preparing her talk on what teeth can tell us about the peopling of the New World, she pulled together the genetics of dental variation with the archaeological evidence to re-frame our understanding of selection on incisor shape.
Incisors are called "shovel-shaped" when the tongue-side of the incisors - the cutting teeth in the front of the mouth, four on top, four on the bottom - have ridges along the sides and biting edge. It is distinctive of Native Americans and populations in East Asia - Korea, Japan and northern China - with an increasing incidence as you travel farther north. Unpersuaded by a previously proposed idea that shoveled incisors were selected for use softening animal hides, she looked at explanations unrelated to teeth.
The genetic mutation responsible for shoveling - which occurs in at least one of the two copies, or alleles, of a gene called EDAR, which codes for a protein called the ectodysplasin A receptor - is also involved in determining the density of sweat glands in the skin, the thickness of hair shafts and ductal branching in mammary glands. Previous genetic analysis of living humans concluded that the mutation arose in northern China due to selection for more sweat glands or sebaceous glands during the last ice age.
"Neither of those is a satisfying explanation," Hlusko said. "There are some really hot parts in the world, and if sweating was so sensitive to selective pressures, I can think of some places where we would have more likely seen selection on that genetic variation instead of in northern China during the Last Glacial Maximum."
The Beringian standstill Clues came from a 2007 paper and later a 2015 study by Hlusko's coauthor Dennis O'Rourke, in which scientists deduced from the DNA of Native Americans that they split off from other Asian groups more than 25,000 years ago, even though they arrived in North American only 15,000 years ago. Their conclusion was that Native American ancestors settled for some 10,000 years in an area between Asia and North America before finally moving into the New World. This so-called Beringian standstill coincided with the height of the Last Glacial Maximum between 18,000 and 28,000 years ago.
According to the Beringian standstill hypothesis, as the climate became drier and cooler as the Last Glacial Maximum began, people who had been living in Siberia moved into Beringia. Gigantic ice sheets to the east prohibited migration into North America. They couldn't migrate southwest because of a large expanse of a treeless and inhospitable tundra. The area where they found refuge was a biologically productive region thanks to the altered ocean currents associated with the last ice age, a landmass increased in size by to the lower sea levels. Genetic studies of animals and plants from the region suggest there was an isolated refugium in Beringia during that time, where species with locally adaptive traits arose. Such isolation is ripe for selection on genetic variants that make it easier for plants, animals and humans to survive.
"If you take these data from the teeth to interpret the evolutionary history of this EDAR allele, you frame-shift the selective episode to the Beringian standstill population, and that gives you the environmental context," Hlusko said. "At that high latitude, these people would have been vitamin D deficient. We know they had a diet that was attempting to compensate for it from the archaeological record, and because there is evidence of selection in this population for specific alleles of the genes that influence fatty acid synthesis. But even more specifically, these genes modulate the fatty acid composition of breast milk. It looks like this mutation of the EDAR gene was also selected for in that ancestral population, and EDAR's effects on mammary glands is the most likely target of the selection."
The EDAR gene influences the development of many structures derived from the ectoderm in the fetus, including tooth shape, sweat glands, sebaceous glands, mammary glands and hair. As a consequence, selection on one trait leads to coordinated evolution of the others. The late evolutionary biologist and author Steven Jay Gould referred to such byproducts of evolution as spandrels.
"This Beringian population is one example of what has happened thousands of times, over millions of years: Human populations form, exist for a little while and then disperse to form new populations, mixing with other groups of people, all of them leaving traces on modern human variation today," Hlusko said. "An important take-home message is that human variation today reflects this dynamic process of ephemeral populations, rather than the traditional concept of geographic races with distinct differences between them."

Oldest peace treaty in the world

IMAGE: This is the oldest-preserved peace treaty between Ramesses II and ?attušili III, c. 1259 B.C. view more 
Credit: Staatliche Museen zu Berlin, Vorderasiatisches Museum, Olaf M. Teßmer
According to archaeologists, the world's oldest peace treaty disproves the widespread notion that in antiquity, peace was not brought about by negotiations, but always by humiliating those who had lost. 

 "More than 3,200 years ago, Egyptians and Hittites ensured each other mutual support in the treaty; neither of them triumphed. This must have been preceded by much negotiating, as is evidenced by extensive correspondence between the rulers", say Director Prof. Dr Achim Lichtenberger and Curator Dr Helge Nieswandt of the University of Münster's Archaeological Museum. "Although the 'victorious peace' dominates over the 'peace of reconciliation' in peace images of antiquity, our research shows that the latter also existed." 

From 28 April, the museum will present a copy of the oldest contract (fig. 1) from the Berlin Pergamon Museum in the exhibition project "Frieden. Von der Antike bis heute" (Peace. From Antiquity to the Present Day). Another copy can be seen in the United Nations Building in New York.

The researchers of the museum and of the Cluster of Excellence "Religion and Politics" also do away with other clichés. A large number of peace images were created not in times of peace, but in times of war, such as the Roman goddess of peace Pax showing on countless coins. "Despite the glorification of war in antiquity, which undoubtedly existed and alienates us: images of the ideal of peace were particularly widespread during wars," says Nieswandt. 

Heap of coins, with Roman coins depicting the goddess of peace, 3rd century AD
© Archäologisches Museum der WWU Münster, Foto: Robert Dylka

He will present the "inflation of peace" on coins (fig. 2) on 23 May at the Cluster of Excellence's conference "PEACE. Theories, Images and Strategies from Antiquity to the Present Day", which is part of the exhibition project.

In the exhibition with the subtitle "Eirene - Pax. Frieden in der Antike" (Peace in Antiquity), the museum will also, for the first time, present 
 Eirene by Cephisodotus, 375/74 AD; bronze-coloured copy
© Archäologisches Museum der WWU Münster, Foto: Silke Hockmann
a bronze-coloured copy of the famous goddess of peace "Eirene" by sculptor Cephisodotus (fig. 3). It symbolises that with peace comes prosperity. "Despite the glorification of war, people from antiquity always knew that it is not war but peace that leads to wealth," says Lichtenberger. 

 Roman coins with ears and handshake from 68 AD, a year of civil war
© Staatliche Museen zu Berlin, Münzkabinett, 18228354, Foto: Dirk Sonnenwald

This ideal is also illustrated by many of the other 160 antique exhibits such as the messenger staff, the handshake and ears of grain (fig. 4). "They show how strongly our Western peace symbols of today are rooted in ancient Greek and Roman images and how they have repeated themselves over centuries. 

Accordingly, the ancient illustrations are often familiar to us."Bronze-coloured goddess of peace and doves in animal idyll
According to Lichtenberger, even the most famous symbol of peace today, the dove, originates from antiquity. The derivation is not linear, however: "While in antiquity, the dove itself did not signify peace, it was closely associated with Aphrodite, the goddess of love. It also appeared in animal idylls in which the peaceful coexistence of animals represented peace. The dove could thus be adapted as a symbol of peace by Christians."

Pax with caduceus on Roman coin
© Archäologisches Museum der WWU Münster, Foto: Robert Dylka
 An allegory of peace in the tradition of antiquity from 1659 by Flemish painter Theodoor van Thulden, depicting horn of plenty and caduceus, also shows how far the ancient symbols extend into later centuries. "According to ancient ideas, the caduceus granted its bearer diplomatic immunity," says Nieswandt. "The fact that the goddess Pax holds it on numerous ancient coin depictions underlines once more the importance that negotiated peace had for antiquity as well". (fig. 5)

Regarding the numerous coin depictions of the goddess of peace "Pax" (fig. 2), Helge Nieswandt explains that she was often, particularly in times of war, shown on coins, the first mass medium of mankind, because rulers thus offered an ideal in reply to reality. 

The researcher will show this in his conference lecture on 23 May using an example of Roman antiquity: "When the order of the Roman Empire fell apart in the 3rd century AD, and when mostly short-lived soldier emperors took turns, there was an 'inflation of peace' on coins." Researchers see this as one example of many for the fact that people in all centuries expressed and depicted a longing for peace, but were not able to secure it in the long run. This guiding principle characterises the exhibition "Peace. From Antiquity to the Present Day".

About the bronze copy of Cephisodotus' Eirene, the scholar explains that it is a statue whose Greek original from the 4th century BC has not survived, but whose popularity and appearance are attested to by numerous Roman copies. Goddess of peace Eirene holds the infant Plutus, the personification of wealth, in her arms. 

The Archaeological Museum has commissioned a restorer with the bronze-coloured copy of this 2.05-metre and thus larger-than-life representation and will for the first time present it to the public at the opening of the exhibition on 28 April. "According to our investigations, the bronze, which is shining like gold, is only one possibility of several coloured versions, but in any case it is more plausible than the white of the plaster. The Münster reconstruction is to be understood as an incentive to see the statue differently than before. (sca/vvm)

Friday, April 20, 2018

Getty Conservation Institute Announces Near Completion of Work at the Tomb of King Tutankhamen

The Getty Conservation Institute (GCI)  has nearly completed its work at the Tomb of Tutankhamen in Egypt, one of the most famous cultural heritage sites in the world. The project —a multiyear collaboration between the GCI and Egypt’s Ministry of Antiquities (formerly known as the Supreme Council of Antiquities) focused on conservation and the creation of a sustainable plan for continued conservation and management of the tomb. Work at the legendary site included the conservation of wall paintings, environmental and infrastructure improvements, and training for future care of the site. 

Conservation work on the wall paintings in the tomb © J. Paul Getty Trust 

"This project greatly expanded our understanding of one of the best known and significant sites from antiquity, and the methodology used can serve as a model for similar sites,” says Tim Whalen, John E. and Louise Bryson Director of the Getty Conservation Institute. “The work at Tutankhamen’s tomb is representative of the kind of collaborative effort the GCI undertakes with colleagues internationally to advance conservation practice and to protect our cultural heritage.” 

The discovery of Tutankhamen’s tomb, located in Egypt’s Valley of the Kings, is considered one of the most spectacular in the history of archaeology. Built hastily upon the death of the young King Tutankhamen, the tomb was buried by flood debris at its entrance soon after it was sealed, and as a result evaded plunder for over 3,000 years. 

After discovering the tomb in 1922, Howard Carter carefully documented and stabilized the tomb’s contents, some of which have been exhibited around the world. The tomb itself became a “must -see” attraction for visitors to Egypt, which resulted in concerns regarding the site’s condition. 

 3D drawing of the tomb. (Courtesy of the Theban Mapping Project)   

The tomb still houses a handful of original objects, including the mummy of Tutankhamen himself (on display in an oxygen- free case), the quartzite sarcophagus with its granite lid on the floor beside it, the gilded wooden outermost coffin, and the wall paintings of the burial chamber. The concerns regarding the tomb included the humidity and carbon dioxide levels, and the dust introduced by visitors. 

“Humidity promotes micro biological growth and may also physically stress the wall paintings, while carbon dioxide creates an uncomfortable atmosphere for visitors themselves,” says Neville Agnew, the GCI senior principal project specialist who has led the project. “But perhaps even more harmful has been the physical damage to the wall paintings. Careful examination showed an accumulation of scratches and abrasion in areas close to where visitors and film crews have access within the tomb’s tight space.” 

The pharaoh Tutankhamen pictured on the north wall of the burial chamber © J. Paul Getty Trust

 Another serious problem in the tomb is the dust visitors bring in on their shoes and clothing, which settles on the floor and the uneven surfaces of the walls. Dust on the walls obscures the brightness of the paintings and necessitates cleaning, which increases the risk of additional paint loss. 

In 2009, the Ministry asked the GCI to collaborate on a project to conserve the tomb and its wall paintings. The GCI has had considerable experience working in Egypt, first on the Tomb of Queen Nefertari in the Valley of the Queens (1986 – 92), and later on the planning for the conservation and management of the Valley of the Queens (beginning in 2006). 

The team of experts working on the Tutankhamen project included an Egypto logist to conduct background research; environmental engineers to investigate the tomb’s microclimatic conditions; microbiologists to study mysterious brown spots on the surface of the wall paintings; documentation specialists, architects, and designers to upgrade the tomb’s infrastructure; scientists to study the original materials of the wall paintings; and conservators to carry out condition recording and treatment and to train local conservators. 

The wall paintings were found to be in relatively stable condition, apart from localized flaking and loss of paint. Most of the flaking was likely due to inconsistencies in the materials used and their application, but other losses were attributed to damage caused by visitors. 

Newly designed barriers now restrict visitor access in these areas so that further losses can be minimized. Stabilization of the paintings addressed paint flaking and plaster instability and also included dust removal and reduction of coatings from previous treatments (past treatments were not always based on thorough understanding of the paintings’ conditions and the causes of their deterioration). Condition monitoring protocols were also established to better evaluate future changes.  

Detail of a wall painting with brown spots © J. Paul Getty Trust 

Also addressed were the mysterious brown spots on the wall paintings. Other tombs do not show the same phenomenon, and Egyptian authorities wondered if the presence of visitors was causing the spots to grow, so the project conducted research to identify the microorganisms and determine if they posed a continued risk. 

The brown spots were already present when Carter first entered the tomb, and a comparison of the spots with historic photographs from the mid -1920s showed no new growth. To confirm this finding , DNA and chemical analysis were undertaken and physical samples of the spots were examined under magnification and then mounted in cross section. The investigation confirmed the spots to be microbiological in origin but concluded they were dead and thus no longer a threat. Because the spots have penetrated into the paint layer, they were not removed since this would harm the wall paintings. 

In addition to the wall paintings conservation, the GCI also facilitated upgrades to the protection and presentation of the site, including infrastructure (walkways, viewing platform, and an air filtration and ventilation system to protect against humidity, carbon dioxide, and dust), new bilingual signage and interpretive materials, training of staff, and devising a pro gram for sustainable maintenance and controlled visitation to the tomb. New lighting will be installed in the fall of 2018. 

“Because the project allowed for unprecedented study of the tomb and its wall paintings, its findings have provided a deeper understanding of tomb construction and decoration practices from the New Kingdom,” says Lori Wong, a project specialist at the GCI and an expert in wall paintings conservation. “This work has also shed new light on the tomb’s condition and the causes of its deterioration, and these findings will be used to protect the tomb for years to come.” 

A project monograph will be published, as well as a book for the general public.

Wednesday, April 18, 2018

Sweet potato history casts doubt on early contact between Polynesia and the Americas

Evidence reported in the journal Current Biology on April 12 shows that sweet potatoes arose before there were any humans around to eat them. The findings also suggest that the sweet potato crossed the ocean from America to Polynesia without any help from people. The discovery raises doubts about the existence of pre-Columbian contacts between Polynesia and the American continent.

"Apart from identifying its progenitor, we also discovered that sweet potato originated well before humans, at least 800,000 years ago," says Robert Scotland from the University of Oxford. "Therefore, it is likely that the edible root already existed when humans first found this plant."

Scotland and colleagues set out to clarify the origin and evolution of the sweet potato, which is one of the most widely consumed crops in the world and an important source of vitamin A precursors. They also aimed to explore a question that has been of interest for centuries: how did the sweet potato, a crop of American origin, come to be widespread in Polynesia by the time Europeans first arrived? In fact, researchers have suggested that the sweet potato's early presence in Polynesia was evidence of pre-European contacts between Americans and Polynesians.

The researchers combined genome skimming and target DNA capture to sequence the whole chloroplasts and 605 single-copy nuclear regions from 199 specimens representing the sweet potato and all of its crop wild relatives. The data strongly suggest that sweet potato arose after a genome duplication event. Its closest wild relative is Ipomoea trifida. The findings confirm that no other extant species was involved in the sweet potato's origin.

Phylogenetic analysis of the DNA sequences produced conflicting family trees. However, the researchers report, those conflicting patterns can be explained by a dual role for I. trifida. Sweet potato arose from I. trifida and later hybridized with I. trifida to produce another, independent sweet potato lineage.

"We demonstrate that the existence of those two different lineages is the result of an ancient hybridization between sweet potato and its progenitor," says Munoz-Rodriguez, first author of the paper. "We conclude that sweet potato evolved at least 800,000 years ago from its progenitor, and then after the two species became distinct, they hybridized."

The findings come as good news for the future of the sweet potato. That's because the loss of genetic diversity in crops is a major threat for food security. One way to improve or reinforce desirable properties in food crops is to cross them with their closest wild relatives. So, Scotland says, the identification of the sweet potato's progenitor opens the door to a more accurate understanding of its potential role in sweet potato breeding.

The new view on sweet potato history also has major implications for understanding human history.

"Our results challenge not only the hypothesis that the sweet potato was taken to Polynesia by humans, but also the long-time argued existence of ancient contacts between Americans and Polynesians," Munoz-Rodriguez says. "These contacts were considered as true based on evidence from chickens, humans, and sweet potato. Evidence from chickens and humans is now considered questionable, and thus sweet potato was the remaining biological evidence of these alleged contacts. Therefore, our results refute the dominant theory and call into question the existence of pre-European contacts across the Pacific."

Tuesday, April 17, 2018

Boy unearths treasure of the Danish king Bluetooth in Germany

René Schön and his student Luca Malaschnitschenko were looking for treasure using metal detectors in January on northern Rügen island when they chanced upon what they initially thought was a worthless piece of aluminium.

But upon closer inspection, they realised that it was a piece of silver, German media reported.
Over the weekend, the regional archaeology service began a dig covering 400 sq metres (4,300 sq ft). It has found a hoard believed to be linked to the Danish king Harald Gormsson, better known as “Harry Bluetooth”, who reigned from around AD 958 to 986.
Braided necklaces, pearls, brooches, a Thor’s hammer, rings and up to 600 chipped coins were found, including more than 100 that date back to Bluetooth’s era, when he ruled over what is now Denmark, northern Germany, southern Sweden and parts of Norway.

“This trove is the biggest single discovery of Bluetooth coins in the southern Baltic Sea region and is therefore of great significance,” the lead archaeologist, Michael Schirren, told national news agency DPA.

The oldest coin is a Damascus dirham dating to 714 while the most recent is a penny dating to 983.
The find suggests that the treasure may have been buried in the late 980s – also the period when Bluetooth was known to have fled to Pomerania, where he died in 987.

“We have here the rare case of a discovery that appears to corroborate historical sources,” said the archaeologist Detlef Jantzen.

Bluetooth is credited with unifying Denmark. The Viking-born king also turned his back on old Norse religion and introduced Christianity to the Nordic country.

But he was forced to flee to Pomerania after a rebellion led by his son Sven Gabelbart.

Wednesday, April 11, 2018

Unusual climate during Roman times plunged Eurasia into hunger and disease

A recent study published in an esteemed academic journal indicates that volcanic eruptions in the mid 500s resulted in an unusually gloomy and cold period. A joint research project of the Chronology Laboratory of the Finnish Museum of Natural History and Natural Resources Institute Finland (Luke) suggests that the years 536 and 541-544 CE were very difficult for many people.

An extended period of little light may make it difficult for humans to survive. The level of production of plants is dependent on the amount of available sunlight. Food production, i.e, farming and animal husbandry, rely on the same solar energy. Humans, meanwhile, become more prone to disease if they are not exposed to enough sunlight to produce vitamin D.

"Our research shows that the climate anomaly, which covered all of the northern hemisphere, was the compound result of several volcanic eruptions," says Markku Oinonen, director of the Chronology Laboratory.

The aerosols that were released into the atmosphere with the eruptions covered the sun for a long time.

The exceptionally poor climate conditions were significantly detrimental to farming and reduced the production of vitamin D among the populace. This means that the people who were already weakened by hunger also had to grapple with a compromised immune system.

Trees are a re­cord of the past
The study is based on dendrochronology or tree-ring dating. The series of annual growth rings from subfossil - or intact - tree deposits covers the past 7,600 years. The trees are often found on the bottom of small lakes, and Luke has been taking samples and recording the findings since the 1990s.
"Researchers have put together an annual growth ring calendar of treeline pine spanning more than 7,600 years. Various historical events can be contrasted with the calendar. The growth ring calendar is an important indicator of global climate change," says researcher Samuli Helama from Luke.
The samples in the recent study were dated with the help of the growth ring calendar at Luke, and sample shavings were carved out of them for each calendar year. The Chronology Laboratory then conducted isotope analyses on the samples.

Car­bon iso­topes in­dic­ate sum­mer weather
The results of the study are based on the analysis of the variation of carbon isotopes in the annual growth rings of trees. The variety in carbon isotopes reflects the photosynthesis of the trees, which in turn is largely dependent on the amount of solar radiation available during the summer.
The new study tracks the correlation of carbon isotope variation and volcanic eruptions from the 19th century until recent years, and shows the dramatic reduction in available sunlight in 536 as well as between 541 and 544 CE. The variation of summer temperatures was similarly reconstructed on the basis of the density of the trees' annual growth rings.

Hard times brought the plague
The unusually poor years coincide with the bubonic plague epidemic that devastated the Roman Empire. The epidemic caused by the Yersinia pestis bacterium began in 542 CE and killed approximately half, or more, of the inhabitants of what was then considered the Eastern Roman Empire. The plague spread through Europe, from the Mediterranean, possibly as far north as Finland, and had killed tens of millions of people by the 8th century.

Tuesday, April 10, 2018

First human migration out of Africa more geographically widespread than previously thought

IMAGE: Fossil finger bone of Homo sapiens from the Al Wusta site, Saudi Arabia. view more 
Credit: Ian Cartwright
A project led by the Max Planck Institute for the Science of Human History has discovered a fossilized finger bone of an early modern human in the Nefud Desert of Saudi Arabia, dating to approximately 90,000 years ago. The discovery, described in Nature Ecology and Evolution, is the oldest directly dated Homo sapiens fossil outside of Africa and the Levant and indicates that early dispersals into Eurasia were more expansive than previously thought.

Researchers conducting archaeological fieldwork in the Nefud Desert of Saudi Arabia have discovered a fossilized finger bone of an early member of our species, Homo sapiens. The discovery is the oldest directly dated Homo sapiens fossil outside of Africa and the immediately adjacent Levant, and indicates that early dispersals into Eurasia were more expansive than previously thought. Prior to this discovery, it was thought that early dispersals into Eurasia were unsuccessful and remained restricted to the Mediterranean forests of the Levant, on the doorstep of Africa. The finding from the Al Wusta site shows that there were both multiple dispersals out of Africa, and these spread further than previously known.

Oldest directly dated Homo sapiens fossil outside of Africa and the Levant
The results, published in Nature Ecology and Evolution, detail the discovery made at the site of Al Wusta, an ancient fresh-water lake located in what is now the hyper-arid Nefud Desert. Numerous animal fossils, including those of hippopotamus and tiny fresh water snails were found at Al Wusta, as well as abundant stone tools made by humans. Among these finds was a well preserved and small fossil, just 3.2 cm long, which was immediately recognized as a human finger bone. The bone was scanned in three dimensions and its shape compared to various other finger bones, both of recent Homo sapiens individuals and bones from other species of primates and other forms of early humans, such as Neanderthals.

The results conclusively showed that the finger bone, the first ancient human fossil found in Arabia, belonged to our own species. Using a technique called uranium series dating, a laser was used to make microscopic holes in the fossil and measure the ratio between tiny traces of radioactive elements. These ratios revealed that the fossil was 88,000 years old. Other dates obtained from associated animals fossils and sediments converged to a date of approximately 90,000 years ago. Further environmental analyses also revealed the site to have been a freshwater lake in an ancient grassland environment far removed from today's deserts.

Lead author Dr. Huw Groucutt, of the University of Oxford and the Max Planck Institute for the Science of Human History, states, "This discovery for the first time conclusively shows that early members of our species colonized an expansive region of southwest Asia and were not just restricted to the Levant. The ability of these early people to widely colonize this region casts doubt on long held views that early dispersals out of Africa were localized and unsuccessful."

Modern deserts of the Arabian Peninsula were once lush grasslands that humans were able to colonize
Project Lead, Professor Michael Petraglia of the Max Planck Institute for the Science of Human History adds, "The Arabian Peninsula has long been considered to be far from the main stage of human evolution. This discovery firmly puts Arabia on the map as a key region for understanding our origins and expansion to the rest of the world. As fieldwork carries on, we continue to make remarkable discoveries in Saudi Arabia."

Friday, April 6, 2018

Genetics of the modern heirs of the Incas shed new lights about their origins and lineages

IMAGE: Iconic sacred citadelle of Machu Picchu, at the edge of the Andes and Amazon, symbol of the largest empire of the Pre Columbian Americas. view more 
Credit: Jose Sandoval
A multinational South American team from Peru, Brasil and Bolivia led by the Universidad de San Martin de Porres at Lima, Peru, published the first genetic study on the modern descendants of the imperial Inka lineages in the journal Molecular Genetics and Genomics. This work supported by funds from the Genographic Project (Geno 2.0), shows new insights about the Inkas origins and lineages.

The Inka people arrived to Cusco valley and in a few centuries they built the Tawantinsuyu, the largest empire in the Americas. The Tawantinsuyu was the cultural climax of 6,000 years of Central Andes civilizations overlapping modern countries of Peru, Bolivia, Ecuador, the South of Colombia and the North of Argentina and Chile. In contrast with the richness of archeological and cultural evidence, pre Columbian history vanishes in time as it intermingles with myths due to the lack of writing systems before the arrival of the European chroniclers.

Very little is known about the Inka origins and some genetic information could help reconstruct part of their history. Unfortunately the mummies and bodily remains of the Inka emperors, worshiped as gods, were burnt and buried in unknown locations due to religious and political persecution by the Christian Conquistadors and Inquisitors, so no direct material remain to study their DNA.

 "Thus for now, only the genetic analysis of modern families of Inka descent could provide some clues about their ancestors" remarks geneticist Jose Sandoval, first author, working at Universidad de San Martin de Porres at Lima, Peru.

There were two foundational myths for the origin of the Inkas before they established in Cusco valley to build their capital city.

One is that Manco Capac and Mama Ocllo, considered children of the Sun God and founder parents of the civilization, came from Lake Titicaca about 500 km southwards from the border of North Bolivia and South Peru, more or less the same region where Tiwanaku empire existed a few centuries before.

The second myth narrates that four Ayar brothers, with divine powers, came out from the caves inside of a hill in the area of Paccarictambo, 50 km south of Cusco and only one of them, Manco, arrived to the Cusco valley.

 Concerning the succession of the rulers (between 12 to 14), most chroniclers mention only one patrilineal heritage, however other authors think that it was a complex selection of military and administrative skills not necessarily electing the son of a previous Inka. "A unique patrilineal cluster would be expected in the first case. In the second case, two or more patrilineal pattern will be evident" says geneticist Ricardo Fujita, senior author, also at Universidad de San Martin de Porres".

The research team included historian Ronald Elward, who studied documentation of twelve Inka noble families and followed up from the conquista times to their contemporary descendants. "Most of them still living in the towns of San Sebastian and San Jeronimo, Cusco, Peru, at present, are probably the most homogeneous group of Inka lineage" says Elward.

Markers for Y chromosome and mtDNA were used for the genetic analysis of these families and compared with a database for 2400 native individuals from Peru, Bolivia, Ecuador and Brazil. "The results show distinctive patrilineal origins to two founder individuals who lived between 1000 to 1500 AD, a period between the decline of former Tiwanaku (south) and Wari (north) contemporary empires, and the rise of the Inca empire a few centuries later" says geneticist Fabricio Santos from the Universidad Federal de Minas Gerais at Belo Horizonte, Brazil.

The first patrilineal haplotype named AWKI-1 (awki means crown prince in quechua language) is found in the putative families descending of 2 earlier Incas Yahuar Huacac and Viracocha. The same pattern of the Inca descendants was also found in individuals living south to Cusco, mainly in Aymaras of Peru and Bolivia.

The second patrilineal haplotype named AWKI-2 was found in one descendant of a more recent Inca, Huayna Capac, father of the two brothers (Huascar and Atahualpa) who were fighting a fraternal war over the empire at the arrival of the Conquistadors. "AWKI-2 is also found in dozens of individuals from different locations in the Andes and occasionally in the Amazon, suggesting a populational expansion" says Dr. Santos.

"In addition to San Sebastian and San Jeronimo, most locations of AWKI-1, AWKI-2 were southwards to Cusco including the basin of lake Titicaca and neighboring Paccarictambo, in agreement with the two foundational myths of the Incas" says Ricardo Fujita, "probably two pictures at different times of the same journey with final destination Cusco" adds Fujita. "It is also remarkable that in these contemporary Inka noblility families there is a continuity since pre Columbian times" says Ronald Elward.

 The analysis of their mtDNA suggested a highly varied matrilineal marker whose counterparts are found all over the Andes reflecting a high genetic flow. "This probably reflects the political alliances by arranged marriages between Cusco nobility and daughters of lords of kingdoms and chiefdoms all over the empire" states Jose Sandoval.

This work is the continuation of several studies performed by the team to reconstruct South American history by Genetics and also funded by a previous grant of the Genographic Project (Geno 1.0) led in South America by Fabricio Santos. Two published works included the unique ancient roots of the Uros, people from the Floating Islands of the Lake Titicaca and the Quechwa-Lamistas in Peruvian Amazon. Modern Uros are Aymara speaking people that some have thought to be people from the Aymara ethnia who profited tourism by living on the floating islands. However the team showed that they were genetically isolated people who had lost their original Uro language, shifting to more the widely used Aymara language.

On the other hand the Kechwa-Lamista are Amazonian people who speak the Andean Quechua language and they were presumed descendants of Andeans Chancas, former enemies of the Incas, and were chased by them towards the Amazon. DNA showed that they are actually descendants of linguistically different Amazonian people who were gathered by Catholic missions and were taught the Quechua language (learn by the missionaries at the Andes) for a better evangelization.

"In some cases Genetics shows us something different than the official history. What is no written or badly written in historical records, can be revealed by what is written in our DNA. " concludes Ricardo Fujita. "This study is just the tip of the iceberg in trying to solve part of several enigmas of one of the most remarkable civilizations. The DNA of one Inka monarch bodily remain or of one direct descendant who lived at the beginning of the Spanish colonization could give more certainty about the Inca lineage, and our team is looking forward to it" declares Jose Sandoval.