Thursday, January 18, 2018

First evidence of sub-Saharan Africa glassmaking



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IMAGE: This is Sub-Saharan Africa glass. view more 
Credit: Abidemi Babatunde Babalola
Scholars from Rice University, University College London and the Field Museum have found the first direct evidence that glass was produced in sub-Saharan Africa centuries before the arrival of Europeans, a finding that the researchers said represents a "new chapter in the history of glass technology."

The discovery is discussed in "Chemical Analysis of Glass Beads from Igbo Olokun, Ile-Ife (SW Nigeria): New Light on Raw Materials, Production and Interregional Interactions," which will appear in an upcoming volume of the Journal of Archaeological Science.

Lead author Abidemi Babatunde Babalola, a recent graduate of Rice with a Ph.D. in anthropology and a visiting fellow at Harvard University, came across evidence of early glassmaking during archaeological excavations at Igbo Olokun, located on the northern periphery of Ile-Ife in southwestern Nigeria. He recovered more than 12,000 glass beads and several kilograms of glass-working debris.

"This area has been recognized as a glass-working workshop for more than a century," Babalola said. "The glass-encrusted containers and beads that have been uncovered there were viewed for many years as evidence that imported glass was remelted and reworked."

However, 10 years ago this idea was challenged when analyses of glass beads attributed to Ile-Ife showed that some had a chemical composition very different from that of known glass production areas. Researchers raised the possibility of local production in Ife, although direct evidence for glassmaking and its chronology was lacking.

"The Igbo Olokun excavations have provided that evidence," Babalola said.

The researchers' analysis of 52 glass beads from the excavated assemblage revealed that none matched the chemical composition of any other known glass-production area in the Old World, including Egypt, the eastern Mediterranean, the Middle East and Asia. Rather, the beads have a high-lime, high-alumina (HLHA) composition that reflects local geology and raw materials, the researchers said.

The excavations provided evidence that glass production at Igbo Olokun dates to the 11th through 15th centuries A.D., well before the arrival of Europeans along the coast of West Africa.

Babalola said the presence of the HLHA glass at other important early West African sites suggests that it was widely traded. He hopes the research will cast more light on the innovation and development of glass in early sub-Saharan Africa and how the regional dynamics in glass production connect with the global phenomenon of glass invention and exchange.

He also hopes his work will help researchers understand its impact on the social, political and economic fabrics of the African societies.

The complexity of the Neanderthals’ origin



Top view of the Montmaurin-La Niche mandible/José María Bermúdez de Castro.
Credit: Image courtesy of CENIEH
A team of scientists from the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), led by José María Bermúdez de Castro, together with the French researcher Amélie Vialet, from the Natural History Museum in Paris, has just published a paper in the journal PLOS ONE on the Middle Pleistocene Montmaurin-La Niche mandible, which reveals the complexity of the origin of the Neanderthals.

This mandible was found by Raoul Cammas on 18 June 1949 in the karstic cavities of Montmaurin within the La Niche cave (France), where stone tools and fossil remains of different species of canids, equids and ursids also appeared, helping to place it in time.

The presumed age of this mandible, between 200,000 and 240,000 years, had led a close morphological similarity to the mandible of European Neanderthals to be presumed, particularly in the teeth, but the mathematical techniques applied to the study of a wide variety of mandibles, including those of a group of recent African ones, show that it is more in line with the most archaic specimens from Europe, including those from Dmanisi.

"We find here an archaic mandible, and dental pieces which taxonomically are indisputably Neanderthal, which helps to support the hypothesis that the Neanderthal lineage did not evolve linearly but in mosaic," explains Bermúdez de Castro.

Comparative studies

Considered for two decades to be the oldest human fossil found in France, the mandible has formed part of different comparative studies, and the description published by G. Billy and Henri V. Vallois in 1977 stands out. That work was undertaken more than 40 years ago, in the context of what was then known and of the theories then current on the colonization of the European continent.

However, human evolution in Europe was undoubtedly more complex than was thought only a couple of decades ago, as is explained in this paper entitled A reassessment of the Montmaurin-La Niche mandible (Haute Garonne, France) in the context of European Pleistocene human evolution, in which Mario Modesto, María Martinón-Torres and Marina Martínez de Pinillos also participated.

The possibility that there could have coexisted at least two hominin lineages, and that interbreeding, prolonged periods of isolation, genetic drift and other processes were habitual in the Middle Pleistocene in Europe is gaining momentum, while at the same time linear hypotheses such as "accretion" are losing ground.

"The appearance of the classic Neanderthals in the Late Pleistocene is a question by no means finally settled. There remain many open questions, and the Montmaurin-La Niche mandible now joins the list of X-files," concludes Bermúdez de Castro.

DNA ends 4,000-year-old Egyptian mummy mystery


 
The Two Brothers are the Museum's oldest mummies and amongst the best-known human remains in its Egyptology collection. They are the mummies of two elite men -- Khnum-nakht and Nakht-ankh -- dating to around 1800 BC.
 
Credit: Manchester Museum, The University of Manchester
 
Using 'next generation' DNA sequencing scientists have found that the famous 'Two Brothers' mummies of the Manchester Museum have different fathers so are, in fact, half-brothers.
The Two Brothers are the Museum's oldest mummies and amongst the best-known human remains in its Egyptology collection. They are the mummies of two elite men -- Khnum-nakht and Nakht-ankh -- dating to around 1800 BC.

However, ever since their discovery in 1907 there has been some debate amongst Egyptologists whether the two were actually related at all. So, in 2015, 'ancient DNA' was extracted from their teeth to solve the mystery.

But how did the mystery start? The pair's joint burial site, later dubbed The Tomb of The Two Brothers, was discovered at Deir Rifeh, a village 250 miles south of Cairo.

They were found by Egyptian workmen directed by early 20th century Egyptologists, Flinders Petrie and Ernest Mackay. Hieroglyphic inscriptions on the coffins indicated that both men were the sons of an unnamed local governor and had mothers with the same name, Khnum-aa. It was then the men became known as the Two Brothers.

When the complete contents of the tomb were shipped to Manchester in 1908 and the mummies of both men were unwrapped by the UK's first professional female Egyptologist, Dr Margaret Murray. Her team concluded that the skeletal morphologies were quite different, suggesting an absence of family relationship. Based on contemporary inscriptional evidence, it was proposed that one of the Brothers was adopted.

Therefore, in 2015, the DNA was extracted from the teeth and, following hybridization capture of the mitochondrial and Y chromosome fractions, sequenced by a next generation method. Analysis showed that both Nakht-Ankh and Khnum-Nakht belonged to mitochondrial haplotype M1a1, suggesting a maternal relationship. The Y chromosome sequences were less complete but showed variations between the two mummies, indicating that Nakht-Ankh and Khnum-Nakht had different fathers, and were thus very likely to have been half-brothers.

Dr Konstantina Drosou, of the School of Earth and Environmental Sciences at the University of Manchester who conducted the DNA sequencing, said: "It was a long and exhausting journey to the results but we are finally here. I am very grateful we were able to add a small but very important piece to the big history puzzle and I am sure the brothers would be very proud of us. These moments are what make us believe in ancient DNA. "

The study, which is being published in the Journal of Archaeological Science, is the first to successfully use the typing of both mitochondrial and Y chromosomal DNA in Egyptian mummies.
Dr Campbell Price, Curator of Egypt and Sudan at Manchester Museum, said: "The University of Manchester, and Manchester Museum in particular, has a long history of research on ancient Egyptian human remains. Our reconstructions will always be speculative to some extent but to be able to link these two men in this way is an exciting first."

Wednesday, January 17, 2018

The earliest domestic turkeys in ancient Mexico


For the first time, research has uncovered the origins of the earliest domestic turkeys in ancient Mexico.

The study also suggests turkeys weren't only prized for their meat - with demand for the birds soaring with the Mayans and Aztecs because of their cultural significance in rituals and sacrifices.

In an international collaboration, researchers from the University of York, the Institute of Anthropology and History in Mexico, Washington State University and Simon Fraser University, studied the remains of 55 turkeys which lived between 300BC and 1500 AD and had been discovered in Mesoamerica- an area stretching from central Mexico to Northern Costa Rica within which pre-Columbian societies such as the Mayans and Aztecs flourished.

Analysing the ancient DNA of the birds, the researchers were able to confirm that modern European turkeys are descended from Mexican ancestors.

The team also measured the carbon isotope ratios in the turkey bones to reconstruct their diets. They found that the turkeys were gobbling crops cultivated by humans such as corn in increasing amounts, particularly in the centuries leading up to Spanish exploration, implying more intensive farming of the birds.

Interestingly, the gradual intensification of turkey farming does not directly correlate to an increase in human population size, a link you would expect to see if turkeys were reared simply as a source of nutrition.

Lead author of the paper and Marie Sk?odowska-Curie Fellow in the Department of Archaeology at the University of York, Dr Aurélie Manin, said:

"Turkey bones are rarely found in domestic refuse in Mesoamerica and most of the turkeys we studied had not been eaten - some were found buried in temples and human graves, perhaps as companions for the afterlife. This fits with what we know about the iconography of the period, where we see turkeys depicted as gods and appearing as symbols in the calendar.

"The archaeological evidence suggests that meat from deer and rabbit was a more popular meal choice for people in pre-Columbian societies; turkeys are likely to have also been kept for their increasingly important symbolic and cultural role".
The fact that some of the turkey bones were uncovered outside of the natural range of the species also suggests that there was a thriving turkey trade in live birds along Mesoamerica's expanding trade routes.

Senior author of the paper from the Department of Archaeology at the University of York, Dr Camilla Speller, said: "Even though humans in this part of the word had been practicing agriculture for around 10,000 years, the turkey was the first animal, other than the dog, people in Mesoamerica started to take under their control.

"Turkeys would have made a good choice for domestication as there were not many other animals of suitable temperament available and turkeys would have been drawn to human settlements searching for scraps"

Some of the remains the researchers analysed were from a cousin of the common turkey - the brightly plumed Ocellated turkey. In a strange twist the researchers found that the diets of these more ornate birds remained largely composed of wild plants and insects, suggesting that they were left to roam free and never domesticated.

"Why two biologically very similar species living in the same area were treated so differently remains a mystery," added Dr Speller.

Monday, January 15, 2018

Possible cause of early colonial-era Mexican epidemic identified


Salmonella enterica, the bacterium responsible for enteric fever, may be the long-debated cause of the 1545-1550 AD 'cocoliztli' epidemic in Oaxaca, Mexico, that heavily affected the native population
Max Planck Institute for the Science of Human History

An international team, led by researchers from the Max Planck Institute for the Science of Human History (MPI-SHH), Harvard University and the Mexican National Institute of Anthropology and History (INAH), has used ancient DNA and a new data processing program to identify the possible cause of a colonial-era epidemic in Mexico.

Many large-scale epidemics spread through the New World during the 16th century but their biological causes are difficult to determine based on symptoms described in contemporaneous historical accounts. In this study, published in Nature Ecology and Evolution, scientists made use of new methods in ancient DNA research to identify Salmonella enterica Paratyphi C, a pathogen that causes enteric fever, in the skeletons of victims of the 1545-1550 cocoliztli epidemic in Mexico.

 After European contact, dozens of epidemics swept through the Americas, devastating New World populations. Although many first-hand accounts of these epidemics were recorded, in most cases it has been difficult, if not impossible, for researchers to definitively identify their causes based on historical descriptions of their symptoms alone. In some cases, for example, the symptoms caused by infection of different bacteria or viruses might be very similar, or the symptoms presented by certain diseases may have changed over the past 500 years. Consequently, researchers have hoped that advancements in ancient DNA analysis and other such approaches might provide a breakthrough in identifying the unknown causes of past epidemics.

The first direct evidence for one of the potential causes of the 1545-1550 cocoliztli epidemic
Of all the colonial New World epidemics, the unidentified 1545-1550 "cocoliztli" epidemic was among the most devastating, affecting large parts of Mexico and Guatemala, including the Mixtec town of Teposcolula-Yucundaa, located in Oaxaca, Mexico. Archaeological excavations at the site have unearthed the only known cemetery linked to this particular outbreak to date.

"Given the historical and archaeological context of Teposcolula-Yucundaa, it provided us with a unique opportunity to address the question regarding the unknown microbial causes responsible for this epidemic," explains Åshild J. Vågene of the MPI-SHH, co-first author of the study. After the epidemic, the city of Teposcolula-Yucundaa was relocated from the top of a mountain to the neighboring valley, leaving the epidemic cemetery essentially untouched prior to recent archaeological excavations. These circumstances made Teposcolula-Yucundaa an ideal site to test a new method to search for direct evidence of the cause of the disease.

The scientists analyzed ancient DNA extracted from 29 skeletons excavated at the site, and used a new computational program to characterize the ancient bacterial DNA. This technique allowed the scientists to search for all bacterial DNA present in their samples, without having to specify a particular target beforehand. This screening method revealed promising evidence of S. enterica DNA traces in 10 of their samples.

Subsequent to this initial finding, a DNA enrichment method specifically designed for this study was applied. With this, the scientists were able to reconstruct full S. enterica genomes, and 10 of the individuals were found to contain a subspecies of S. enterica that causes enteric fever. This is the first time scientists have recovered molecular evidence of a microbial infection from this bacterium using ancient material from the New World.

Enteric fever, of which typhoid fever is the best known variety today, causes high fevers, dehydration, and gastro-intestinal complications. Today, the disease is considered a major health threat around the world, having caused an estimated 27 million illnesses in the year 2000 alone. However, little is known about its past severity or worldwide prevalence.

A new tool in discovering past diseases

"A key result of this study is that we were successful in recovering information about a microbial infection that was circulating in this population, and we did not need to specify a particular target in advance," explains Alexander Herbig, also of the MPI-SHH and co-first author of the study. In the past, scientists usually targeted a particular pathogen or a small set of pathogens, for which they had prior indication.

"This new approach allows us to search broadly at the genome level for whatever may be present," added Johannes Krause, director of the Department of Archaeogenetics at the MPI-SHH and last author of the study. Kirsten Bos, also of the MPI-SHH, adds, "This is a critical advancement in the methods available to us as researchers of ancient diseases - we can now look for the molecular traces of many infectious agents in the archaeological record, which is especially relevant to typical cases where the cause of an illness is not known a priori."

Archaeologist discovers the earliest tomb of a Scythian prince



Deep in a swamp in the Russian republic of Tuva, SNSF-funded archaeologist Gino Caspari has discovered an undisturbed Scythian burial mound. All the evidence suggests that this is not only the largest Scythian princely tomb in South Siberia, but also the earliest -- and that it may be harbouring some outstandingly well-preserved treasures.

Gino Caspari made the most significant find in his career to date not with a shovel, but at a computer. A recipient of Swiss National Science Foundation (SNSF) funding, archaeologist Caspari discovered a circular structure on high-resolution satellite images of the Uyuk River valley (Siberia) on his computer screen. An initial trial dig carried out this summer by the Bern University scientist together with the Russian Academy of Sciences and the Hermitage Museum confirmed his suspicion: the structure is a kurgan, a Scythian princely tomb.

Looking back at the beginnings

Working with a Swiss-Russian team, Caspari was able to prove that the burial mound -- referred to as Tunnug 1 (or Arzhan 0) -- was similar in construction to the kurgan Arzhan 1 located only ten kilometres away to the northeast. Arzhan 1 had long been regarded as the earliest Scythian princely tomb in the region, which is also known as the "Siberian Valley of Kings" owing to the numerous kurgans found there. The earliest princely tombs consist of a stone packing with a circular arrangement of chambers. The walls of the chambers are made of larch logs.

Scythian burial objects typically include weapons, horse's harnesses and objects decorated in the so-called animal style.

Wooden beams found by Caspari during the test excavation date back to the 9th century BC, predating Arzhan 1, which was built at the turn of the 9th to the 8th century BC and excavated in the 1970s. "We have a great opportunity here," says a delighted Caspari, commenting on the results of the trial dig published in the current issue of Archaeological Research in Asia.

"Archaeological methods have become considerably more sophisticated since the 1970s. Today we have completely different ways of examining material to find out more about the transition from the Late Bronze Age to the Iron Age," remarks the SNSF-funded researcher. He also stresses that the way we look at prehistoric times is changing radically thanks to genetics, isotope analysis and geophysical methods as well as developments in geographic information systems and remote sensing.

Protective armour of ice

The Arzhan 0 burial mound is in an inaccessible location amid swampy terrain, which also makes it harder for grave robbers to reach.

"The kurgan is five arduous hours by off-road vehicle from the nearest settlement," Caspari points out.

As it may never have been disturbed, it could contain similar treasures to Arzhan 2. Between 2001 and 2004, a German team of archaeologists discovered an undisturbed burial chamber in Arzhan 2 containing the richest collection of burial artefacts ever found in the Eurasian steppe. Over a thousand gold objects had been placed with the two corpses in the tomb's main chamber, in addition to magnificently adorned weapons, pots and horses with exquisite harnesses. Made of solid gold, the necklace of the Scythian prince from Arzhan 2 weighs 2 kilos alone. But the date of the burial is put at the 7th century BC, i.e. well into the Iron Age.

The climatic characteristics of the Siberian soil add to Caspari's hopes. In the Uyuk Valley, the permafrost layer largely begins just a few metres below the surface. Everything above that thaws in summer, and organic material rots. However, beneath the thick stone packing of the kurgans, the rays of sunlight are unable to thaw out the soil.

"Very rarely ice lenses form directly beneath the kurgans," explains Caspari.

The ice prevents the decay of organic matter and preserves sensitive material. Caspari is expecting further finds to be unearthed in the course of the project: "If we're lucky, we might even find some well-preserved wood carvings or carpets under the stones, or perhaps an ice mummy."

Wednesday, January 10, 2018

Dual migration created genetic 'melting pot' of the first Scandinavians


IMAGE
IMAGE: These are skeletal fragments from Hummervikholmen, one of sites featured in this study. view more 
Credit: Beate Kjørslevik
New genomic data suggest that the first human settlers on the Scandinavian peninsula followed two distinct migration routes. The study published January 9 in the open access journal PLOS Biology led by researchers from Uppsala University with an international team of collaborators, also indicates that the resulting mixed population genetically adapted to the extreme environmental conditions.

There is consistent evidence of a human presence in the Scandinavian peninsula from around 11,700 years ago, and similarities between stone tool artefacts found in Scandinavia and those seen in both Western Europe and Eastern Europe suggest that several groups may have migrated into the area when the ice retreated. The migration routes and genetic makeup of the first Scandinavians have, however, previously been elusive.


By sequencing the genomes of 7 hunter-gatherers excavated across Scandinavia and dated to be 9,500-6,000 years old, the researchers found that migrations into the Scandinavian peninsula most likely followed two routes; one from central Europe and one from the Northeast along the Norwegian Atlantic Coast. The two groups met and mixed in Scandinavia, creating a genetically diverse population with many genetic variants that have not been passed down to modern-day Europeans.

The research team also investigated whether the individuals showed signs of adaptation to the cold and low daylight conditions found in high-latitude environments. They discovered that several genetic variants in the hunter-gatherers were linked to a gene associated with physical performance, which they hypothesise could be part of the physiological adaptation to cold. The hunter-gatherers also had a high frequency of genetic variants linked to reduced skin pigmentation -- a known adaptation to environments with low UV radiation, such as those at high latitude.

"We used cutting-edge genomic approaches to investigate hypotheses about the early colonization of northern Europe after the ice-sheet of the last glaciation retracted. It is really great to see how evidence from different disciplines can be combined to understand these complex past demographic processes," said population geneticist Torsten Günther, one of the lead authors.

He adds: "Our findings are important for human genetics, archaeology and anthropology, and it will be interesting to see what similar approaches can tell us about the post glacial population dynamics in other parts of Europe and the rest of the world."