Storia Genetica d'Europa

The Genetic History of Europe

The European continent has a complex human evolutionary history. The first modern humans are believed to have entered Europe some 40,000 years ago, at a time when Neanderthals were the predominant Homo species (or subspecies). In the subsequent millennia a series of environmental and climatic fluctuations have occurred, which caused much of the flora and fauna of the continent to move and migrate in order to maintain viable populations in the habitats to which they had evolved. Humans were no different. These factors, together with successive waves of new peoples from the Middle East and  elsewhere, such as the so-called Neolithic farmers, have combined to produce the present genetic variation in Europe today. The impact of these events, and of the more recent historical episodes of migration and admixture, is hotly debated among geneticists, historians, demographers and so on.

This project aims to investigate the present population structure of Europe to gather new insights on the role played by these events in shaping continental genetic variation. We initially focused on Y chromosome  markers to build up on the large body of data available on European populations. Our results (Busby et al, 2012 -http://rspb.royalsocietypublishing.org/content/279/1730/884.long ) showed that microsatellites require careful handling when tackling issues like lineage dating.

At the moment we are focusing on the impact of historical events, as in the past the focus has been very much on the Palaeolithic-Neolithic dichotomy and not much more. We are currently exploring genome-wide data to investigate these questions in collaboration with colleagues in the Dept of statistics and at UCL. Stay tuned for future updates!

Fonte: Human Evolutionary Genetic Group - University of Oxford

Il colore dei mesolitici

Gli studi più recenti lasciano concludere che i cacciatori raccoglitori europei (in questo caso, della Spagna) del Mesolitico avevano la pelle scura. analogamente a quelli indiani. Poi, per un processo che fu - più probabilmente - di selezione ed incroci, la colorazione si schiarì, in modo più completo in europa ed in modo variegato in India. Un altro fatto rilevante - anche se più tecnico - è l'appartenenza allall'aplogruppo Y C6: questo permette di concludere che l'aplogruppo C6 sia stato pan-eurasiatico. Ciò è importante, in quanto sembra essere legato a più elevate difese contro le infezioni, che sarebbero divenute indubbiamente più frequenti con l'introduzione dell'allevamento e la maggiore densità di popolazione del Neolitico.

Gli Europei di 7.000 anni fa avevano occhi blu e pelle scura: l'aspetto delle antiche popolazioni di cacciatori-raccoglitori è stato ricostruito per la prima volta grazie all'analisi del Dna dei resti di un individuo vissuto nel Mesolitico in Spagna. Il risultato, pubblicato sulla rivista Nature, si deve al gruppo coordinato da Carles Lalueza-Fox, dell'Istituto di Biologia Evolutiva a Barcellona.

I resti dell'uomo sono stati scoperti nel 2006 con un altro scheletro maschile nel sito La Brana - Arintero in Valdelugueros, nel Nord della Spagna. Entrambi gli uomini sono vissuti nel Mesolitico, il periodo compreso fra 10.000 a 5.000 anni fa (tra il Paleolitico e Neolitico), che si conclude con l'avvento dell'agricoltura e l'allevamento, pratiche arrivate dal Medio Oriente.

La ricerca è stata condotto sul Dna estratto da un dente di uno dei due uomini, indicato come La Brana 1. L'analisi mostra come alcune nuove abitudini introdotte dall'agricoltura abbiano influenzato le popolazioni, facendo emergere nuovi geni associati con il sistema immunitario e la dieta. L'arrivo del Neolitico, con una dieta a base di carboidrati e nuovi agenti (come virus batteri e parassiti) trasmessi dagli animali domestici, ha comportato infatti problemi metabolici e immunologici che si sono tradotti in adattamenti genetici nelle popolazioni. Tra questi vi è la capacità di digerire il lattosio, che il cacciatore-raccoglitore di La Brana infatti non aveva.

L'uomo aveva anche difficoltà a digerire gli alimenti contenenti amidi rispetto agli agricoltori del Neolitico. Per quanto riguarda l'aspetto fisico: il mix di occhi azzurri, pelle d'ebano e capelli scuri suggerisce che il passaggio alla pelle più chiara degli europei moderni era ancora in corso durante il Mesolitico ma il colore degli occhi era cambiato prima. ''La sorpresa più grande - osserva Lalueza-Fox - è stata scoprire che questa persona possedeva versioni dei geni africani che determinano la pigmentazione della pelle, il che indica che aveva la pelle scura, anche se non possiamo stabilire l'esatta tonalità''. Ma per l'esperto, ancora più sorprendente è, contemporaneamente, la presenza di geni responsabili degli occhi azzurri negli europei di oggi.

Il Dna dell'antico uomo racconta anche le sue parentele: aveva un antenato comune con i coloni del sito Paleolitico di Mal'ta, vicino al lago Baikal in Siberia. Inoltre i suoi 'parenti' attuali potrebbero essere nel Nord Europa, come Svezia e Finlandia, le cui popolazioni sono le più vicine sotto il profilo genetico. Dati, conclude Lalueza-Fox, che indicano ''una continuità genetica nelle popolazioni dell'Eurasia centrale e occidentale''.

Brown-skinned, blue-eyed, Y-haplogroup C-bearing European hunter-gatherer from Spain (Olalde et al. 2014)

Ricostruzione ipotetica dell'aspetto di un cacciatore raccoglitore mesolitico europeo: pelle scura, occhi azzurri

There is nothing like a little ancient DNA weirdness to start off 2014, which promises to be as exciting as 2013 was.

The new study La Brana 1 identifies it as ancestral in the SLC24A5 locus in which virtually all Europeans are derived. This comes in the heels of the Loschbour preprint which identified that sample from Luxembourg as also being ancestral. Taken together, it's now clear that hunter-gatherers from Mesolithic Western Europe were brown.

Curiously, it now seems that both Europe and India were (in part) inhabited by brown people and became lighter by a process of admixture + selection. The process went "all the way" in Europe, but a cline of pigmentation was sustained in India.

The other finding (not mentioned in the abstract) is that La Brana 1 belonged to Y-haplogroup C6! This is a low-frequency European clade of haplogroup C. So now, we have evidence that haplogroup C is not eastern Eurasian (as the presence of its subclades in Australia, India, East Asia, and the Americas might suggest), but a pan-Eurasian entity. It remains to be seen whether this C-in-Europe can be pushed further back in time, but finding it in Mesolithic Iberia reduces the chance that it's some random eastern Eurasian who made it to the outskirts of Europe recently.

Finally, La Brana 1 has derived alleles at loci associated with pathogen resistance. This might be important, because a common hypothesis is that Europeans developed this type of resistance during the Neolithic as they started interacting with the pathogens of domesticated species and started living in less-hygienic higher-density settlements.


Nature (2014) doi:10.1038/nature12960

Derived immune and ancestral pigmentation alleles in a 7,000-year-old Mesolithic European 

Iñigo Olalde et al.

Ancient genomic sequences have started to reveal the origin and the demographic impact of farmers from the Neolithic period spreading into Europe1, 2, 3. The adoption of farming, stock breeding and sedentary societies during the Neolithic may have resulted in adaptive changes in genes associated with immunity and diet. However, the limited data available from earlier hunter-gatherers preclude an understanding of the selective processes associated with this crucial transition to agriculture in recent human evolution. Here we sequence an approximately 7,000-year-old Mesolithic skeleton discovered at the La Braña-Arintero site in León, Spain, to retrieve a complete pre-agricultural European human genome. Analysis of this genome in the context of other ancient samples suggests the existence of a common ancient genomic signature across western and central Eurasia from the Upper Paleolithic to the Mesolithic. The La Braña individual carries ancestral alleles in several skin pigmentation genes, suggesting that the light skin of modern Europeans was not yet ubiquitous in Mesolithic times. Moreover, we provide evidence that a significant number of derived, putatively adaptive variants associated with pathogen resistance in modern Europeans were already present in this hunter-gatherer.

-----------------------------

Spanish hunter-gatherer had blue eyes and dark skin 

La Braña 1, name used to baptize a 7,000 years old individual from the Mesolithic Period, whose remains were recovered at La Braña-Arintero site in Valdelugueros (León, Spain) had blue eyes and dark skin. These details are the result of a study conducted by Carles Lalueza-Fox, researcher from the Spanish National Research Council (CSIC), in collaboration with the Centre for GeoGenetics (Denmark). La Braña 1 represents the first recovered genome of an European hunter-gatherer. The research is published in Nature 

The skeleton of La Braña 1, as it was discovered in 2006 [Credit: J.M. Vidal Encina] 

The Mesolithic, a period that lasted from 10,000 to 5,000 years ago (between the Paleolithic and the Neolithic), ends with the advent of agriculture and livestock farming, coming from the Middle-East. The arrival of the Neolithic, with a carbohydrate-based diet and new pathogens transmitted by domesticated animals, entailed metabolic and immunological challenges that were reflected in genetic adaptations of post-Mesolithic populations. Among these is the ability to digest lactose, which La Braña individual could not do. Lalueza-Fox states: "However, the biggest surprise was to discover that this individual possessed African versions in the genes that determine the light pigmentation of the current Europeans, which indicates that he had dark skin, although we can not know the exact shade." 

La Braña 1, the name used to baptize a 7,000-year-old individual from the Mesolithic Period, had blue eyes and dark skin [Credit: Spanish National Research Council] 

CSIC researcher, who works at the Institute of Evolutionary Biology (a joint centre of CSIC and the University Pompeu Fabra (UPF), located in Barcelona, adds: "Even more surprising was to find that he possessed the genetic variations that produce blue eyes in current Europeans, resulting in a unique phenotype in a genome that is otherwise clearly northern European." The study of the genome suggests that current populations nearest to La Braña 1 are in northern Europe, such as Sweden and Finland. In addition, the work points out that La Braña 1 has a common ancestor with the settlers of the Upper Paleolithic site of Mal'ta, located in Lake Baikal (Siberia), whose genome was recovered a few months ago. Lalueza-Fox concludes: "These data indicate that there is genetic continuity in the populations of central and western Eurasia. In fact, these data are consistent with the archeological remains, as in other excavations in Europe and Russia, including the site of Mal'ta, anthropomorphic figures -called Paleolithic Venus- have been recovered and they are very similar to each other." 

Frontal view of the La Braña 1 skull [Credit: J.M. Vidal Encina] 

DNA with an "exceptional" preservation La Braña-Arintero site was discovered by chance in 2006 and excavated by Julio Manuel Vidal Encinas, archeologist of the Council of Castilla y León. The cave, located in a cold mountainous area with a steady temperature and 1,500 meters below the sea level, contributed to the "exceptional" preservation of the DNA from two individuals found inside, and they were called La Braña 1 and La Braña 2. According to Iñigo Olalde, lead author of the study, "the intention of the team is to try to recover the genome of the individual called La Braña 2, which is worse preserved, in order to keep obtaining information about the genetic characteristics of these early Europeans." Source: Spanish National Research Council (CSIC) [January 26, 2014]

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Link

Pigmenti preistorici

Analisi dei pigmenti usati 

nell'arte rupestre preistorica

 Un team che coinvolge ricercatori del Consiglio nazionale delle ricerche spagnolo ha analizzato, per la prima volta, due figure rupestri di ripari situati nel complesso archeologico di Minateda, a Hellin (Albacete). Hanno stili diversi e sono separati da diversi millenni nel tempo. I risultati, pubblicati nel Journal of Archaeological Science , mostrano che la composizione del dipinto nella preistoria non ha cambiato in migliaia di anni e che non c'erano connotazioni culturali o rituali nel suo farsi. 

La composizione della pittura nella preistoria non cambia in migliaia di anni e la sua realizzazione non aveva connotazioni rituali, secondo una nuova ricerca [Crediti: CSIC] 

La prima delle figure analizzate, raffigurante un bovide, appartiene all'arte levantina praticata dai nomadi cacciatori-raccoglitori che abitavano la penisola iberica circa 10.000 anni fa. D'altra parte, la seconda figura, raffigurante un quadrupede, ha uno stile schematico, sviluppato dai primi produttori, agricoltori e allevatori che vivevano nella zona compresa tra 6.500 e 3.500 anni fa. Il primo stile è caratterizzato dal naturalismo delle sue forme e scene, mentre la seconda illustra le sue ragioni, a volte raggiungendo anche l'astrazione. Gli artisti utilizzati ossidi di ferro e terrigeni come pigmenti. Questi materiali sono facilmente reperibili nell'ambiente dei rifugi analizzati: il Grande Abrigo de Minateda, il più emblematico per definire l'origine e l'evoluzione di arte rupestre nel bacino del Mediterraneo della Penisola Iberica, e la Abrigo del Barranco de la Mortaja. Alberto Jorge, CSIC ricercatore presso il Museo Nazionale di Scienze Naturali, afferma: "Le composizioni dei pigmenti utilizzati in entrambi gli stili, separati da diversi millenni nel tempo, sono identici, il che significa che gli artisti non si spengono le ricette intenzioni come era in precedenza pensò. La verità è che si tratta di un materiale abbondante e di buona qualità pigmentazione che era facile da trovare nelle vicinanze ". Nuove interpretazioni Un'altra conclusione dei lavori ha implicazioni nella metodologia di ricerca dei pigmenti di arte rupestre all'aperto. La presenza di ossalato di calcio sarebbe dimostrare che il pigmento e portante fuse con lo strato esterno nei secoli. Jorge spiega: "Questo risultato potrebbe mettere in discussione gli studi condotti finora, sulla base di distinguere tre livelli stratigrafici - superficie, pigmenti e patina-, in quanto questi sono continuamente fusi e modificati, che introduce un fattore casuale chiaro nel dating". I ricercatori hanno anche rilevato la presenza di alcuni acidi grassi, il che suggerisce che quando i pigmenti sono stati elaborati, applicati o conservati, potrebbero venire a contatto con pelli di animali. CSIC ricercatore aggiunge: "Da ora in poi, dobbiamo essere molto cauti quando si parla sui rituali nella preparazione dei pigmenti, in quanto queste interpretazioni si avvicinò quando sostanze come fosfati di calcio, interpretati come carbonizzata e le ossa schiacciato, sono stati trovati nei pigmenti. Queste estrapolazioni non sono corrette in quanto abbiamo anche trovato queste sostanze nel substrato roccioso stessa " .

 Fonte: Spanish National Research Council [14 gennaio 2014]

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Arco Neolitico rinvenuto grazie allo scioglimento delle nevi.

Melting snow reveals Neolithic bow, arrows

A melting patch of ancient snow in the mountains of Norway has revealed a bow and arrows that were probably used by hunters to kill reindeer as long ago as 5,400 years.

The oldest of the arrows was 5,400 years old. The bow and arrow design is strikingly similar to those found in other frigid locales, such as the Yukon. Though people from these two far-flung regions never met, they seemed to have separately developed similar adaptations [Credit: Martin Callanan]

The discovery highlights the worrying effects of climate change, said study author Martin Callanan, an archaeologist at the Norwegian University of Science and Technology.

"It's actually a little bit unnerving that they're so old and that they're coming out right now," Callanan told LiveScience. "It tells us that there's something changing."

Componenti (aste e punte) di frecce neolitiche.

Parti dell'arco lungo neolitico

Renne: vivono nelle valli, ma salgono sui monti d'estate per trovare refrigerio ed allontanarsi dal fastidio degli insetti.

Locked in snow

Callanan and his colleagues spend every summer hiking up the Trollheim and Dovre mountains, a few hours south of Trondheim, Norway, to study the snow patches in the area, track snow melt and look for archaeological artifacts. The mountains stretch 6,200 feet (1,900 meters) above sea level, and at the highest elevations, only rocks and snow prevail year-round.

In 2010 and 2011, a patch of snow melted, revealing an ancient bow and several arrows that had been locked in the snow for centuries. The bow was made from a common type of elm that grows at lower altitudes along the coast. The arrows were tipped in slate and set in different types of wood.

Radioisotope dating revealed that the Neolithic bow was about 3,800 years old, while the oldest of the arrows were 5,400 years old. 

Stone Age hunters probably used the bow and arrows to kill reindeer, which spend summer days at high altitudes. The mountain retreat would have allowed the animals a respite from pesky insects, while standing on snow patches would have helped the shaggy creatures keep cool, Callanan said. Those predictable habits likely made them easy prey for ancient hunters.

No one knows exactly who left these ancient hunting instruments, but the bow and arrows have a design that's strikingly similar to those found thousands of miles away in other frigid landscapes, such as the Yukon, Callanan said.

"The people in Norway, they didn't have any contact with people in the Yukon, but they have the same type of adaptation," Callanan said. "Across different cultures, people have acted in the same way."

Decomposing artifacts

Finding such well-preserved tools is rare, said E. James Dixon, an archaeologist and director of the Maxwell Museum of Anthropology at the University of New Mexico, who was not involved in the study. "It's one of the rare glimpses that we have into this Neolithic-period archery technology," Dixon said.

However, while the find itself is stunning, the climate change that caused such ancient snow to melt is bad for archaeology, he said.

Artifacts locked in ice can be preserved for thousands of years.

"As soon as ice melts and it comes out, it's subject to decomposition and we lose it," Dixon told LiveScience. "For every artifact we find, there are probably hundreds, maybe thousands, that are lost and just destroyed forever."

The bow and arrows are described in the September issue of the journal Antiquity. 

See more photos of the ancient bow and arrows.

Author: Tia Ghose | Source: LiveScience [September 30, 2013]

Effetto della prima agricoltura sull'umanità

Early agriculture had dramatic effects on 

humans

The introduction of agriculture in Europe was followed by regional population crashes despite trends of demographical growth, reports research published in Nature Communications this week. Sean Downey, assistant professor in the University of Maryland's Department of Anthropology, was co-author of the paper. The work suggests that these sharp population decreases weren't due to changing climatic conditions, and therefore the authors propose internal causes. The research represents a major revision to our understanding of how the introduction of agricultural technology impacted humans.

Map of Central and North Western Europe. Points indicate archaeological site locations and colours delineate the sub-regions used to estimate demographic patterns [Credit: Nature Communications/doi:10.1038/ncomms3486]

Stephen Shennan, professor of theoretical archaeology at the Institute of Archaeology, University College London, received grant funding from the European Research Council to study early agriculture and its impact on populations across Europe. His multidisciplinary team of researchers includes co-author Downey, and Mark Thomas, Research Department of Genetics, Evolution and Environment, University College London, who designed the statistical analysis necessary to produce the findings.

Agriculture was introduced in the Aegean (modern day Turkey) around 8,500 years ago and steadily spread across Europe, reaching France around 7,800 years ago, and Britain, Ireland and northern Europe approximately 6,000 years ago. In all instances, the introduction of agriculture meant a drastic change in food production and consumption patterns, which led to a population boom. Utilizing radiocarbon dating, and an innovative new method for improving the accuracy of this data, the study's authors examined how population levels changed over time across Europe during the late Mesolithic, ("Middle Stone age") and Early Neolithic ("New Stone age").

The research team discovered that, in all of the 12 different European regions studied, from the South of France to Scotland and Denmark, drastic population fluctuations can be observed. In fact, they note that in some cases population declines were as significant as 30-60 percent from the highest levels achieved after the introduction of agriculture. These dramatic changes in population are of similar scale to the decrease estimated for the much later "Black Death".

The authors found that those fluctuations cannot be associated with climatic factors; however, the exact reasons for this population decline remains unknown.

"It's striking that the development of agriculture – one of humanity's major evolutionary steps – failed to buffer against widespread social collapse during this early period of rapid population growth in Europe," explains Downey. "At this point in the research we can only speculate at the direct causes, but the study demonstrates that agriculture-based societies in the past were vulnerable to population collapse on a broad scale." Downey continues by explaining the study's finding: "There were no correlations between the collapse of regional populations and known climate shifts. It wasn't the climate, so we think it must have been the long-term impact new agricultural technologies had on local environments in reducing resources. The stress this caused among farmers was likely exacerbated by other well-known consequences of living in higher-density populations: increased incidence of social conflict and of disease."

Source: University of Maryland [October 01, 2013]

IDENTITA' DELL'OSSIDIANA IN 10 SECONDI

I ricercatori dell'Università di Sheffield hanno sviluppato un metodo per  determinare l'origine dell'ossidiana che richiede solo 10 secondi -- Dozzine di volte più veloce del metodo attualmente in uso -- per mezzo di uno strumento portatile a mano, che può essere usato negli scavi archeologici.

Dr Ellery Frahm using pXRF [Credit: University of Sheffield]

L'ossidiana, cioé il 'vetro vulcanico' che si ritrova in natura, è liscio, duro e molto più affilato di un bisturi quando sia fratturato: il che lo rese un materiale molto ricercato per ottenerne stumenti di pietra, per tutta la storia dell'umanità. I più antichi strumenti di ossidiana furono trovati circa  due milioni d'anni fa nell'Africa orientale e alcuni bisturi sono tutt'oggi in ossidiana (per esempio, in oculistica, ndt.).  

La composizione chimica dell'ossidiana varia da vulcano a vulcano e le 'impronte digitali' chimiche permettono ai ricercatori di  confrontare un artefatto d'ossidiana sfruttando proprio l'origine vulcanica del materiale.  I test chimici spesso coinvolgono laboratori d'analisi dedicati specificamente all'uopo, persino con reattori nucleari, che richiedono mesi o anni d'attesa dopo lo scavo.

Il nuovo procedimento adotta una tecnica d'analisi  detta "fluorescenza portatile a raggi X" (portable X-ray fluorescence = pXRF) che richiede uno strumento portatile non più grande e non dissimile da un telefono portatile cordless. Questa metodica è comodissima, dando la possibilità all'archeologo d'identificare l'origine dell'oggetto di pietra  sul campo, invece di doverlo spedire lontano, risparmiando così tempo e denaro. Sarà usata prima per studiare gli strumenti d'ossidiana fatti dai primi esseri umani, includendo Neanderthal ed Erectus, decine di migliaia d'anni fa.
Il Dr Ellery Frahm dell'Università di Sheffield, Dipartimento di Archeologia, è molto soddisfatto di potere esaminare i reperti sul campo, senza più le lunghe attese che erano richieste in passato e soprattutto del fatto che il riconoscimento sia fatto contestualmente al momento dello scavo, sul sito di scavo, con risultati entro 10 secondi per ciò che riguarda la provenienza dell'ossidiana.

La ricerca è stata condotta in Armenia, "perché si tratta di uno dei territori naturalmente più ricchi di ossidiana in assoluto ed insieme uno dei paesaggi culturali più ricchi nel mondo, con assemblaggi litici di numerosi siti del Paleolitico che sono composti prevalentemente, se non unicamente, di ossidiana". 
Il presente lavoro è il più recente: prima la ricerca era condotta in siria, un'area nella quale gli attuali eventi bellici stanno mettendo a rischio tutto l'insieme dell'eredità culturale del paese. 

Questa ricerca globalmente ha avuto origine  dal fatto che il dipartimento sia entrato  nel circuito - a finanziamento Unione europea - Marie Curie "New Archaeological Research Network for Integrating Approaches to Ancient Material Studies," conosciuto meglio sotto l'acronimo di NARNIA. Il dr Frahm sostiene che la ricerca di Sheffield a mezzo NARNIA  unisce  lavoro laboratoristico archeologico al lavoro archeologico sul campo: tenedo in mente due scopi fondamentali. "Lavorare dove prima non potevamo lavorare e rispondere a domande a cui prima non potevamo rispondere."

Il Dr Frahm si dichiara estremamente soddisfatto del fatto che l'analisi chimica sia stata portata via ai "camici bianchi" per essere consegnata agli "scarponi infangati". Più specialisti presenti sul campo significa sempre migliori risultati pratici. 

Source: University of Sheffield [September 09, 2013]

Researchers at the University of Sheffield have developed a method of sourcing obsidian artefacts that takes only 10 seconds -- dozens of times faster than the current methods -- with a handheld instrument that can be used at archaeological excavations.

Dr Ellery Frahm using pXRF [Credit: University of Sheffield]

Obsidian, naturally occurring volcanic glass, is smooth, hard, and far sharper than a surgical scalpel when fractured, making it a highly desirable raw material for crafting stone tools for almost all of human history. The earliest obsidian tools, found in East Africa, are nearly two million years old, and obsidian scalpels are still used today in specialised medical procedures.

The chemistry of obsidian varies from volcano to volcano, and the chemical "fingerprints" allow researchers to match an obsidian artefact to the volcanic origin of its raw material. The chemical tests often involve dedicated analytical laboratories, even nuclear reactors, and take place months or years after an archaeological site has been excavated.

The new process uses an analytical technique called portable X-ray fluorescence (pXRF), which involves a handheld instrument about the size, shape, and weight of a cordless drill. This portability enables archaeologists to identify the origins of stone tools in the field rather than having to send off artefacts to a distant lab. The newly developed method, which saves time and money, will first be used to study obsidian tools made by early humans, including Neanderthals and Homo erectus, tens of thousands of years ago.

Dr Ellery Frahm from the University of Sheffield's Department of Archaeology explained: "Obsidian sourcing has, for the last 50 years, involved chemical analysis in a distant laboratory, often taking five minutes per artefact, completely separate from the process of archaeological excavation. We sought to bring new tools for chemical analysis with us into the field, so we can do obsidian sourcing as we excavate or survey an archaeological site, not wait until months or years later to learn the results. We can now analyse an obsidian artefact in the field, and just 10 seconds later, we have an answer for its origin.

"We carried out the research in Armenia because it has one of the most obsidian-rich natural and cultural landscapes in the world, and the lithic assemblages of numerous Palaeolithic sites are predominantly, if not entirely, composed of obsidian."

The work is the latest of Dr Frahm's achievements in the field of obsidian sourcing, an area that he previously researched in Syria, prior to the current conflict situation which now threatens the country's heritage.

This research arose from the department's involvement in the EU-funded Marie Curie network "New Archaeological Research Network for Integrating Approaches to Ancient Material Studies," known by its acronym as NARNIA. Dr Frahm explained that Sheffield's research with NARNIA includes uniting archaeological labwork and fieldwork in the field: "We have a broad remit on the project, but we are driven by two goals: work where we couldn't work before, and answer what we couldn't answer before."

Dr Frahm continued: "Here at Sheffield we're shifting chemical analysis from the realm of 'white lab coats' to 'muddy boots.' The more that archaeologists and specialists in various fields can work together on-site the better.

Source: University of Sheffield [September 09, 2013]