New Method Confirms Humans and Neandertals Interbred

Technical objections to the idea that Neandertals interbred with the ancestors of Eurasians have been overcome, thanks to a genome analysis method described in the April 2014 issue of the journal GENETICS. The technique can more confidently detect the genetic signatures of interbreeding than previous approaches and will be useful for evolutionary studies of other ancient or rare DNA samples.

“Our approach can distinguish between two subtly different scenarios that could explain the genetic similarities shared by Neandertals and modern humans from Europe and Asia,” said study co-author Konrad Lohse, a population geneticist at the University of Edinburgh.

The first scenario is that Neandertals occasionally interbred with modern humans after they migrated out of Africa. The alternative scenario is that the humans who left Africa evolved from the same ancestral subpopulation that had previously given rise to the Neandertals.

Many researchers argue the interbreeding scenario is more likely, because it fits the genetic patterns seen in studies that compared genomes from many modern humans. But the new approach completely rules out the alternative scenario without requiring all the extra data, by using only the information from one genome each of several types: Neandertal, European/Asian, African and chimpanzee.

The same method will be useful in other studies of interbreeding where limited samples are available. “Because the method makes maximum use of the information contained in individual genomes, it is particularly exciting for revealing the history of species that are rare or extinct,” said Lohse. In fact, the authors originally developed the method while studying the history of insect populations in Europe and island species of pigs in South East Asia, some of which are extremely rare.

Lohse cautions against reading too much into the fact that the new method estimates a slightly higher genetic contribution of Neandertals to modern humans than previous studies. Estimating this contribution is complex and is likely to vary slightly between different approaches.

“This work is important because it closes a hole in the argument about whether Neandertals interbred with humans. And the method can be applied to understanding the evolutionary history of other organisms, including endangered species,” said Mark Johnston, Editor-in-Chief of the journal GENETICS.

First Eurasians left Africa up to 130,000 years ago

A team of researchers led by the University of Tübingen's Professor Katerina Harvati has shown that anatomically modern humans spread from Africa to Asia and Europe in several migratory movements. The first ancestors of today's non-African peoples probably took a southern route through the Arabian Peninsula as early as 130,000 years ago, the researchers found. The study is published by Professor Katerina Harvati and her team from the Institute for Archaeological Sciences at the University of Tübingen and the Senckenberg Center for Human Evolution and Palaeoenvironment, in collaboration with colleagues from the University of Ferrara, Italy, and the National Museum of Natural History, France. The study appears in the online Early Edition of the Proceedings of the National Academy of Sciences.

The Out-of-Africa model that best fits both the genetic and cranial shape data. A first migration along the Indian Ocean rim occurred as early as 130 thousand years ago (green arrow) and was followed by a second, more recent migration wave into Eurasia (red arrow).

Credit: Katerina Harvati/University of Tübingen and Senckenberg Center for Human Evolution and Palaeoenvironment

The scientists tested different hypothetical dispersal scenarios, taking into account the geography of potential migration routes, genetic data and cranial comparisons. They found that the first wave of migration out of Africa started earlier than previously thought, taking place as early as the late Middle Pleistocene -- with a second dispersal to northern Eurasia following about 50,000 years ago.

Most scientists agree that all humans living today are descended from a common ancestor population which existed 100,000 to 200,000 years ago in Africa. The decreasing genetic and phenotypic diversity observed in humans at increasing distances from Sub-Saharan Africa has often been interpreted as evidence of a single dispersal 50,000 to 75,000 years ago. However, recent genetic, archaeological and palaeoanthropological studies challenge this scenario.

Professor Harvati's team tested the competing out-of-Africa models of a single dispersal against multiple dispersals of anatomically modern humans. The scientists compared modern human crania from different parts of the world, neutral genetic data, and geographical distances associated with different dispersal routes. Likewise, they reconstructed population split times from both the genetic data and as predicted by each competing model. Because each dispersal scenario is associated with specific geographic and temporal predictions, the researchers were able to test them against the observed neutral biological distances between groups, as revealed from both genetic and cranial data.

"Both lines of evidence -- anatomical cranial comparisons as well as genetic data -- support a multiple dispersal model," says Katerina Harvati. The first group of our ancestors left Africa about 130,000 years ago and followed a coastal route through the Arabian Peninsula to Australia and the west Pacific region. "Australian aborigines, Papuans and Melanesians were relatively isolated after the early dispersal along the southern route," says Hugo Reyes-Centeno, first author of the study and member of the Tübingen team. He adds that other Asian populations appear to be descended from members of a later migratory movement from Africa to northern Eurasia about 50,000 years ago.

The researchers are confident that continued field work and advances in genetics will allow for fine-tuning of models of human expansion out of Africa. So far we can only speculate whether, for example, severe droughts in East Africa occurring between 135,000 and 75,000 years ago prompted migration or had an impact on the local evolution of human populations. The southern route region is a vast geographical space that has been understudied by archaeologists and anthropologists, so future work in this area will help support their findings.

A woman at the Last Supper

 I have commented before on a woman at the Last Supper

 in Da Vinci's famous picture:

http://archaeologynewsreport.blogspot.com/2013/02/a-woman-sitting-at-da-vincis-last-supper.html

and Federico Barocci's, painted in 1580,

http://archaeologynewsreport.blogspot.com/2013/06/more-on-woman-in-da-vincis-last-supper.html

Here's still another manifestation:

Hendrick Goltzius, The Last Supper, 1598. Engraving, state i/iii, plate and sheet 20.1 x 13.4 cm. University of San Diego

The second person to Christ's left is pretty clearly a young woman - notice her hair, youthful features, no beard. He also seem to have his arm around a child!

A gold signet ring bearing the name of Egyptian Pharoah Seti I in a 3,300-year-old coffin at the foot of Tel Shadud in the Jezreel Valley

 Complete article

 

Gold scarab with symbol of Pharaoh Seti I set in a ring found in a 3,300 year old coffin in the Jezreel Valley
Photo Credit: Clara Amit, courtesy of the Israel Antiquities Authority


A gold signet ring bearing the name of Egyptian Pharoah Seti I was among the personal belongings of a wealthy Canaanite recently discovered in a 3,300-year-old coffin at the foot of Tel Shadud in the Jezreel Valley.


The skeleton of an adult was found inside the clay coffin. Next to it was more pottery, a bronze dagger, bronze bowl and hammered pieces of bronze.

Also found next to the deceased was an Egyptian scarab seal, encased in gold and affixed to a ring. This item is used to seal documents and objects.

The name of the crown of Pharaoh Seti I, who ruled ancient Egypt in the 13th century BCE, appears on the seal. Seti I was the father of Ramses II, identified by some scholars are the pharaoh mentioned in the Biblical story of the Israelites’ Exodus from Egypt.



 

The Egyptian coffin lid after it was cleaned up.
Photo by: Clara Amit, courtesy of the Israel Antiquities Authority

Already in the first year of his reign (1294 BCE) a revolt broke out against Seti I in the Beit Shean Valley, but he conquered that region and established Egyptian rule in Canaan.

Seti’s name on the seal symbolizes power and protection, and the reference to him on the scarab found in the coffin aided the researchers in dating the time of burial. A cemetery dating to Seti I’s reign was previously uncovered at Beit Shean, the center of Egyptian rule in the Land of Israel, and similar clay coffins were exposed.

Tel Shadud preserves the Biblical name “Sarid” and the mound, located in the northern part of the Jezreel Valley close to Kibbutz Sarid, is often referred to as Tel Sarid.

The graves of two men and two women who may have been family members were located nearby, researchers said, noting the find is evidence of Egyptian control of the Jezreel Valley in the 13th century BCE (Late Bronze Age).

Neanderthals and Cro-magnons did not coincide on the Iberian Peninsula

The meeting between a Neanderthal and one of the first humans, which we used to picture in our minds, did not happen on the Iberian Peninsula. That is the conclusion reached by an international team of researchers from the Australian National University, Oxford University, the UPV/EHU-University of the Basque Country, University of Maryland, Universitat de Girona and the University of Oviedo, after redoing the dating of the remains in three caves located on the route through the Pyrenees of the first beings of our species: L'Arbreda, Labeko Koba and La Viña. The paper, entitled The chronology of the earliest Upper Palaeolithic in northern Iberia: New insights from L'Arbreda, Labeko Koba and La Viña, has been published in the Journal of Human Evolution.

Until now, the carbon 14 technique, a radioactive isotope which gradually disappears with the passing of time, has been used to date prehistoric remains. When about 40,000 years, in other words approximately the period corresponding to the arrival of the first humans in Europe, have elapsed, the portion that remains is so small that it can become easily contaminated and cause the dates to appear more recent. It was from 2005 onwards that a new technique began to be used; it is the one used to purify the collagen in DNA tests. Using this method, the portion of the original organic material is obtained and all the subsequent contamination is removed.

And by using this technique, scientists have been arriving at the same conclusions at key sites across Europe:  "We can see that the arrival of our species in Europe took place 8,000 years earlier than what had been thought and we can see the earliest datings of our species and the most recent Neanderthal ones, in which, in a specific regional framework, there is no overlapping," explained Alvaro Arrizabalaga, professor of the department of Geography, Prehistory and Archaeology, and one of the UPV/EHU researchers alongside María-José Iriarte and Aritza Villaluenga.

The three caves chosen for the recently published research are located in Girona (L'Arbreda), Gipuzkoa (Labeko Koba) and Asturias (La Viña); in other words, at the westernmost and easternmost tips of the Pyrenees and it was where the flow of populations and animals between the peninsula and continent took place. "L'Arbreda is on the eastern pass; Labeko Koba, in the Deba valley, is located on the entry corridor through the Western Pyrenees (Arrizabalaga and Iriarte excavated it in a hurry in 1988 before it was destroyed by the building of the Arrasate-Mondragon bypass) and La Viña is of value as a paradigm, since it provides a magnificent sequence of the Upper Palaeolithic, in other words, of the technical and cultural behaviour of the Cro-magnons during the last glaciation", pointed out Arrizabalaga.

The selecting of the remains was very strict allowing only tools made of bones or, in the absence of them, bones bearing clear traces of human activity, as a general rule with butchery marks, in other words, cuts in the areas of the tendons so that the muscle could be removed. "The Labeko Koba curve is the most consistent of the three, which in turn are the most consistent on the Iberian Peninsula," explained Arrizabalaga. 18 remains were dated at Labeko Koba and the results are totally convergent with respect to their stratigraphic position, in other words, those that appeared at the lowest depths are the oldest ones.

The main conclusion -"the scene of the meeting between a Neanderthal and a Cro-magnon does not seem to have taken place on the Iberian Peninsula"- is the same as the one that has been gradually reached over the last three years by different research groups when studying key settlements in Great Britain, Italy, Germany and France.  "For 25 years we had been saying that Neanderthals and early humans lived together for 8,000-10,000 years. Today, we think that in Europe there was a gap between one species and the other and, therefore, there was no hybridation, which did in fact take place in areas of the Middle East," explained Arrizabalaga. The UPV/EHU professor is also the co-author of a piece of research published in 2012 that puts back the datings of the Neanderthals. "We did the dating again in accordance with the ultrafiltration treatment that eliminates rejuvenating contamination, remains of the Mousterian, the material culture belonging to the Neanderthals from sites in the south of the Peninsula. Very recent dates had been obtained in them -up to 29,000 years- but the new datings go back to 44,000 years older than the first dates that can be attributed to the Cro-Magnons," explained the UPV/EHU professor.

Reference

R.E Wood, A. Arrizabalaga, M. Camps, S. Fallon, M.-J. Iriarte-Chiapusso, R. Jones, J. Maroto, M. de la Rasilla, D. Santamaría, J. Soler, N. Soler, A. Villaluenga, T.F.G. Higham. The chronology of the earliest Upper Palaeolithic in northern Iberia: New insights from L'Arbreda, Labeko Koba and La Viña, Journal of Human Evolution (2014), http://dx.doi.org/10.1016/j.jhevol.2013.12.017

Julià Maroto, Manuel Vaquero, Álvaro Arrizabalaga, Javier Baena, Enrique Baquedano, Jesús Jordá, Ramon Julià, Ramón Montes, Johannes Van Der Plicht, j, Pedro Rasines, Rachel Wood. Current issues in late Middle Palaeolithic chronology: New assessments from Northern Iberia Quaternary International (2012) doi:10.1016/j.quaint.2011.07.007

Neanderthals were no strangers to good parenting

Archaeologists at the University of York are challenging the traditional view that Neanderthal childhood was difficult, short and dangerous.

A research team from PALAEO (Centre for Human Palaeoecology and Evolutionary Origins) and the Department of Archaeology at York offer a new and distinctive perspective which suggests that Neanderthal children experienced strong emotional attachments with their immediate social group, used play to develop skills and played a significant role in their society.

The traditional perception of the toughness of Neanderthal childhood is based largely on biological evidence, but the archaeologists, led by Dr Penny Spikins, also studied cultural and social evidence to explore the experience of Neanderthal children.

In research published in the Oxford Journal of Archaeology, they found that Neanderthal childhood experience was subtly different from that of their modern human counterparts in that it had a greater focus on social relationships within their group. Investigation of Neanderthal burials suggests that children played a particularly significant role in their society, particularly in symbolic expression.

The research team, which also included Gail Hitchens, Andy Needham and Holly Rutherford, say there is evidence that Neanderthals cared for their sick and injured children for months and often years. The study of child burials, meanwhile, reveals that the young may have been given particular attention when they died, with generally more elaborate graves than older individuals.

Neanderthal groups are believed to have been small and relatively isolated, suggesting important implications for the social and emotional context of childhood. Living in rugged terrain, there will have been little selection pressure on overcoming the tendency to avoid outside groups with a consequent natural emotional focus on close internal connections.

Dr Spikins, who has a new book on why altruism was central to human evolutionary origins, How Compassion Made Us Human, (Pen and Sword) published later this year, said: "The traditional view sees Neanderthal childhood as unusually harsh, difficult and dangerous. This accords with preconceptions about Neanderthal inferiority and an inability to protect children epitomising Neanderthal decline.

"Our research found that a close attachment and particular attention to children is a more plausible interpretation of the archaeological evidence, explaining an unusual focus on infants and children in burial, and setting Neanderthal symbolism within a context which is likely to have included children.

"Interpretations of high activity levels and frequent periods of scarcity form part of the basis for this perceived harsh upbringing. However, such challenges in childhood may not be distinctive from the normal experience of early Palaeolithic human children, or contemporary hunter-gatherers in particularly cold environments. There is a critical distinction to be made between a harsh childhood and a childhood lived in a harsh environment."

Two Thousand Year Old Ossuaries Containing Jewish Bones from the Second Temple Period were Seized this Weekend in Jerusalem

Photograph: the IAA Unit for the Prevention of Antiquities Robbery.

The ossuaries were allegedly plundered recently from an magnificent ancient burial cave in the Jerusalem region

A number of suspects were apprehended in the early hours of Friday (28.3) in a joint operation by inspectors of the IAA Unit for the Prevention of Antiquities Robbery and detectives and patrolmen of the Shefet police station in Jerusalem. They were caught while in possession of eleven decorated stone ossuaries – ancient coffins – that the Jewish population used for burial in the Second Temple period, two thousand years ago. Some of the ossuaries still contained the skeletal remains of the deceased.

The suspects – residents of Jerusalem, Tel Aviv and the Arab village of Abadiyah, in the vicinity of Bethlehem – were caught red-handed by a team of patrolmen and detectives from the Shefet Station in Jerusalem when they were closing a deal to sell the ossuaries to Jewish merchants, near the Hizma checkpoint north of Jerusalem.

The inspectors of the IAA Unit for the Prevention of Antiquities Robbery immediately recognized that these are special ancient ossuaries of unique significance. It is suspected the ossuaries were recently looted from an ancient burial cave in the region of Jerusalem.

The suspects were arrested on the spot and taken in for questioning under caution by investigators of the IAA and the Shefet police station. Their remand was extended Friday morning by the Jerusalem Magistrates Court.

The Jewish population used stone ossuaries for secondary burial during the Second Temple period and they were very common from the second century BCE until the first century CE. The ossuaries are decorated with typical Jewish symbols, among them the lily flower, the six-petal rosette and other symbols. The decorations adorning the ossuaries were a major element of the Jewish art of the period.

Shallow engravings, etched in the past by means of a sharp stylus, were found on the walls of two of the seized ossuaries. They cite the names of the deceased whose bones were collected in the coffins. One of the engraved ossuaries that were found bore the name “Ralfin”, written in squared Hebrew script characteristic of the Second Temple period. This name is apparently a Hebraized form of an unusual Roman name. According to Dr. Eitan Klein, deputy director of the Unit for the Prevention of Antiquities Robbery, who examined the ossuaries, “this is the first time this name appears on an ossuary from the Land of Israel”. On the other ossuary is a Greek inscription that could not be deciphered, and below it the name “Yo‘azar”, in squared Hebrew script. The name Yo‘azar is a common Jewish name in the Second Temple period, and occurs in contemporary written sources, such as Josephus’ writings. The name appears in this form and a slightly different form – “Yeho‘azar” – on numerous Jewish ossuaries from this period.

Some of the ossuaries were engraved with inscriptions in squared Hebrew script, characteristic of the Second Temple period and some bore Greek inscriptions, including the names of the deceased.

According to Dr. Eitan Klein, “these are singular finds. The inscriptions on the ossuaries provide us with additional characters and names from amongst the Jewish population in the Second Temple period, and the motifs adorning the ossuaries will supplement our knowledge with new information about the world of Jewish art in this period”. Dr. Klein stated, “There is no doubt that the ossuaries were recently looted from a magnificent burial cave in Jerusalem. Remnants of paint remained on top of the ossuaries and the containers themselves belong to the group of “magnificent Jerusalem” ossuaries that were manufactured in the city in antiquity”.

The Israel Antiquities Authority reports that the bones found inside the ossuaries will be turned over to the Ministry of Religious Affairs for burial.

Humans and saber-toothed tiger met in Germany 300,000 years ago

Scientists excavating at the Schöningen open-cast coal mine in north-central Germany have discovered the remains of a saber-toothed cat preserved in a layer some 300,000 years old -- the same stratum in which wooden spears were found, indicating that early humans also inhabited the area, which at that time was the bank of a shallow lake.

The discovery sheds new light on the relationship between early humans and beasts of prey. It is highly likely that humans were confronted by saber-toothed cats at the Schöningen lakeside. In that case, all the human could do was grab his up to 2.3m long spear and defend himself. In this context, the Schöningen spears must be regarded as weapons for defense as well as hunting -- a vital tool for human survival in Europe 300,000 years ago.

Archaeologists uncovered a first tooth of a young adult Homotherium latidens in October 2012. Measuring more than a meter at the shoulder and weighing some 200kg, the saber-tooth was no pussycat. It had razor-sharp claws and deadly jaws with upper-jaw canines more than 10cm long.

The find shows that the saber-toothed cat died out later in central Europe than previously believed. Along with the sensational wooden spears, the same level has yielded bones and stone tools indicating that early humans -- probably Homo heidelbergenis -- hunted horses and camped along a 100m stretch of the lakeside.

The new finds demonstrate that a long time before anatomically modern humans, Homo sapiens sapiens have reached Europe some 40,000 years ago, early man was able to defend himself against highly dangerous animals with his weapon technology.

World’s oldest weather report could revise Bronze Age chronology

A new translation of a 6-foot-tall calcite block called the Tempest Stela suggests the Egyptian pharaoh Ahmose ruled at a time 30 to 50 years earlier than previously thought—a finding that could change scholars’ understanding of a critical juncture in the Bronze Age.

Courtesy of Metropolitan Museum of Art

 

An inscription on a 3,500-year-old stone block from Egypt may be one of the world’s oldest weather reports—and could provide new evidence about the chronology of events in the ancient Middle East.

A new translation of a 40-line inscription on the 6-foot-tall calcite block called the Tempest Stela describes rain, darkness and “the sky being in storm without cessation, louder than the cries of the masses.”

Two scholars at the University of Chicago’s Oriental Institute believe the unusual weather patterns described on the slab were the result of a massive volcano explosion at Thera—the present-day island of Santorini in the Mediterranean Sea. Because volcano eruptions can have a widespread impact on weather, the Thera explosion likely would have caused significant disruptions in Egypt. 

The new translation suggests the Egyptian pharaoh Ahmose ruled at a time closer to the Thera eruption than previously thought—a finding that could change scholars’ understanding of a critical juncture in human history as Bronze Age empires realigned. The research from the Oriental Institute’s Nadine Moeller and Robert Ritner appears in the spring issue of the Journal of Near Eastern Studies.

The Tempest Stela dates back to the reign of the pharaoh Ahmose, the first pharaoh of the 18^th Dynasty. His rule marked the beginning of the New Kingdom, a time when Egypt’s power reached its height. The block was found in pieces in Thebes, modern Luxor, where Ahmose ruled.

If the stela does describe the aftermath of the Thera catastrophe, the correct dating of the stela itself and Ahmose’s reign, currently thought to be about 1550 B.C., could actually be 30 to 50 years earlier.

“This is important to scholars of the ancient Near East and eastern Mediterranean, generally because the chronology that archaeologists use is based on the lists of Egyptian pharaohs, and this new information could adjust those dates,” said Moeller, assistant professor of Egyptian archaeology at the Oriental Institute, who specializes in research on ancient urbanism and chronology.

In 2006, radiocarbon testing of an olive tree buried under volcanic residue placed the date of the Thera eruption at 1621-1605 B.C. Until now, the archeological evidence for the date of the Thera eruption seemed at odds with the radiocarbon dating, explained Oriental Institute postdoctoral scholar Felix Hoeflmayer, who has studied the chronological implications related to the eruption. However, if the date of Ahmose’s reign is earlier than previously believed, the resulting shift in chronology “might solve the whole problem,” Hoeflmayer said.

The revised dating of Ahmose’s reign could mean the dates of other events in the ancient Near East fit together more logically, scholars said. For example, it realigns the dates of important events such as the fall of the power of the Canaanites and the collapse of the Babylonian Empire, said David Schloen, associate professor in the Oriental Institute and Near Eastern Languages & Civilizations on ancient cultures in the Middle East.

“This new information would provide a better understanding of the role of the environment in the development and destruction of empires in the ancient Middle East,” he said.

For example, the new chronology helps to explain how Ahmose rose to power and supplanted the Canaanite rulers of Egypt—the Hyksos—according to Schloen. The Thera eruption and resulting tsunami would have destroyed the Hyksos’ ports and significantly weakened their sea power.

In addition, the disruption to trade and agriculture caused by the eruption would have undermined the power of the Babylonian Empire and could explain why the Babylonians were unable to fend off an invasion of the Hittites, another ancient culture that flourished in what is now Turkey.   

‘A TEMPEST OF RAIN’

Some researchers consider the text on the Tempest Stela to be a metaphorical document that described the impact of the Hyksos invasion. However, Ritner’s translation shows that the text was more likely a description of weather events consistent with the disruption caused by the massive Thera explosion.

Ritner said the text reports that Ahmose witnessed the disaster—the description of events in the stela text is frightening.

The stela’s text describes the “sky being in storm” with “a tempest of rain” for a period of days. The passages also describe bodies floating down the Nile like “skiffs of papyrus.”

Importantly, the text refers to events affecting both the delta region and the area of Egypt further south along the Nile. “This was clearly a major storm, and different from the kinds of heavy rains that Egypt periodically receives,” Ritner said.

In addition to the Tempest Stela, a text known as the Rhind Mathematical Papyrus from the reign of Ahmose also makes a special point of mentioning thunder and rain, “which is further proof that the scholars under Ahmose paid close and particular attention to matters of weather,” Ritner said.

Marina Baldi, a scientist in climatology and meteorology at the Institute of Biometeorology of the National Research Council in Italy, has analyzed the information on the stela along with her colleagues and compared it to known weather patterns in Egypt.

A dominant weather pattern in the area is a system called “the Red Sea Trough,” which brings hot, dry air to the area from East Africa. When disrupted, that system can bring severe weather, heavy precipitation and flash flooding, similar to what is reported on the Tempest Stela.

“A modification in the atmospheric circulation after the eruption could have driven a change in the precipitation regime of the region. Therefore the episode in the Tempest Stela could be a consequence of these climatological changes,” Baldi explained.

Other work is underway to get a clearer idea of accurate dating around the time of Ahmose, who ruled after the Second Intermediate period when the Hyksos people seized power in Egypt. That work also has pushed back the dates of his reign closer to the explosion on Thera, Moeller explained. 

Ancient nomads spread earliest domestic grains along Silk Road

Findings push back earliest known East-West interaction along Silk Road by 2,000 years  

Charred grains of barley, millet and wheat deposited nearly 5,000 years ago at campsites in the high plains of Kazakhstan show that nomadic sheepherders played a surprisingly important role in the early spread of domesticated crops throughout a mountainous east-west corridor along the historic Silk Road, suggests new research from Washington University in St. Louis.

"Our findings indicate that ancient nomadic pastoralists were key players in an east-west network that linked innovations and commodities between present-day China and southwest Asia," said study co-author Michael Frachetti, PhD, an associate professor of archaeology in Arts & Sciences at Washington University and principal investigator on the research project.

"Ancient wheat and broomcorn millet, recovered in nomadic campsites in Kazakhstan, show that prehistoric herders in Central Eurasia had incorporated both regional crops into their economy and rituals nearly 5,000 years ago, pushing back the chronology of interaction along the territory of the 'Silk Road' more than 2,000 years," Frachetti said.

The study, to be published April 2 in the Proceedings of the Royal Society B, establishes that several strains of ancient grains and peas had made their way across Eurasia thousands of years earlier than previously documented.

While these crops have been known to exist much earlier in ancient China and Southwest Asia, finding them intermingled in the Bronze Age burials and households of nomadic pastoralists provides some of the earliest concrete signs for east-west interaction in the vast expanse of Eurasian mountains and the first botanical evidence for farming among Bronze Age nomads.

Bread wheat, cultivated at least 6,000 years ago in Southwest Asia, was absent in China before 2500 B.C. while broomcorn millet, domesticated 8,000 years ago in China, is missing in southwest Asia before 2000 B.C. This study documents that ancient grains from eastern China and soutwest Asia had made their way to Kazakhstan in the center of the continent by 2700-2500 B.C. (nearly 5,000 years ago).

"This study starts to rewrite the model for economic change across Eurasia," said first author Robert Spengler, PhD, a paleoethnobotanist and research associate in Arts & Sciences at WUSTL.

"It illustrates that nomads had diverse economic systems and were important for reshaping economic spheres more generally."

Findings are based on archaeobotanical data collected from four Bronze Age pastoralist campsites in Central Eurasian steppe/mountains: Tasbas and Begash in the highlands of Kazakhstan and Ojakly and Site 1211/1219 in Turkmenistan.

"This is one of the first systematic applications of archaeobotany in the region, making the potential for further future discovery very exciting," Spengler said.

Frachetti and a team of WUSTL researchers led the on-site excavations, working closely with archaeologists based in Turkmenistan, Kazakhstan and Italy. Spengler conducted the paleoethnobotany laboratory work at WUSTL, under the directorship of Gayle J. Fritz, PhD, professor of archaeology and expert in human-plant relationships.

"Finding this diverse crop assemblage at Tasbas and Begash illustrates first evidence for the westward spread of East Asian and Southwest Asian crops eastward, and the surprise is that it is nomads who are the agents of change," Frachetti said.

Contemporary Europeans have as many as three times more Neanderthal variants in genes than Asians and Africans

Although Neanderthals are extinct, fragments of their genomes persist in modern humans. These shared regions are unevenly distributed across the genome and some regions are particularly enriched with Neanderthal variants. An international team of researchers led by Philipp Khaitovich of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and the CAS-MPG Partner Institute for Computational Biology in Shanghai, China, show that DNA sequences shared between modern humans and Neanderthals are specifically enriched in genes involved in the metabolic breakdown of lipids. This sharing of genes is seen mainly in contemporary humans of European descent and may have given a selective advantage to the individuals with the Neanderthal variants.

Skeleton of a neanderthal (left) and a modern human (right).

© Ian Tattersall

The researchers analyzed the distribution of Neanderthal variants in the genomes of eleven contemporary human populations of African, Asian and European descent. They found that genes involved in the lipid synthesis contained a particularly high number of Neanderthal variants in contemporary humans of European origin, but not in Asians and Africans. “These sequences show signs of recent positive selection”, says Philipp Khaitovich of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and the CAS-MPG Partner Institute for Computational Biology in Shanghai, China. “This may indicate that they give modern humans carrying the Neanderthal genotype a selective advantage.”

Analyzing the influence of Neanderthal variants on lipid processing in modern humans, the researchers further found recent evolutionary changes in lipid concentration and expression of metabolic enzymes in brains of humans of European origin. “We don’t know what these lipid concentration changes do to the brain, but the fact that Neanderthal variants might have changed our brain composition has interesting implications”, says Philipp Khaitovich.  Further work is needed, however, in order to fully assess the potential functional effects of these changes.