Showing posts with label Neolithic. Show all posts
Showing posts with label Neolithic. Show all posts

Wednesday, 27 February 2013

Y chromosomes of Corded Ware at Wroclaw-Jagodno (SW Poland)

From the paper:
Two teeth coming from fossil human skeletons were examined in the Molecular Technology Institute of Forensic Medicine Department, Wroclaw Medical University. It was stated that both teeth came from two men on the basis of the gene of amelogenin variants study. Determining polymorphisms of SNP type from chromosome Y resulted in categorizing skeleton from grave no. 1 with very high probability into haplogroup G, whereas skeleton from grave no. 2 with very high probability into one of three haplogroups J, I or E*.
Table 2:

It appears that dots represent identity with the reference sequence, so for example M201 has a dot for skeleton 1 which indicates a T at position 15,027,529 (GRCh37) which is the position where this mutation has occurred. So, the attribution of skeleton 1 to haplogroup G seems reasonable, and suggests continuity between the Neolithic population of Europe (where G is over-represented) and this CW individual.
It's not clear to me how skeleton 2 is attributed to J or I or E* on the basis of these SNPs. If anyone can figure it out, post in the comments.

Journal of Archaeological Science doi:10.1016/j.jas.2013.02.002
Assessment of late Neolithic pastoralist's life conditions from the Wroclaw-Jagodno site (SW Poland) on the basis of physiological stress markers
Bohdan Gworys et al.
So-called physiological stress markers are extremely valuable in assessing life conditions of old human populations. They constitute effects of adverse environmental conditions, which leave traces on skeleton. Those traces allow for partial assessment of life conditions not only in environmental and social but also cultural aspects for prehistoric populations. The aim of this study is to estimate the influence of general environmental conditions on human organism at the final stage of the Neolithic period – in the Corded Ware culture. Two skeletons discovered in a tumulus on the outskirts of Wroclaw in the Jagodno district have been subjected to assessment. Their age at the moment of death has been determined in both cases on the basis of multi-feature analysis of changes occurring in formation of particular morphologic features of skeleton and teeth. Attention has been paid to the obliteration degree of skull sutures and the surface state of chewing tooth crowns. A comprehensive DNA analysis has been conducted determining sex of the remains. Also bacteriological analysis of the research material has been conducted. Measurements of all available metric features of the skeletons have been performed with the use of the Martin method. Inventory and basic description of the finds accompanying skeleton remains have been carried out as well. Intensity of the following physiological stress markers have been defined and evaluated: Harris lines; cribra orbitalia; cribra cranii. Skull morphology, degree of suture obliteration, surface state of chewing tooth crowns and estimation of degree of bone development of postcranial skeleton indicate that both skeletons detailed age was about 16 – 18 years. Harris lines on the femur were formed in the 2nd and the 3rd year of life and on both tibias – in the 2nd year of life. Obtained results indicate that those people were expose to stress connected with food deficit when they were very young. Poor porotic changes on the skull and isotopic data suggest that their life quality increased at later age.
Link

Wednesday, 20 February 2013

AAPA 2013 abstracts

The program of the 2013 meeting of the American Association of Physical Anthropologists is now online (pdf). As always, there is plenty of interest here, so I'll just highlight a few titles that caught my eye; feel free to add more in the comments.


Neolithic human mitochondrial haplogroup H genomes and the genetic origins of Europeans.
Haplogroup (hg) H dominates present-day Western European mitochondrial (mt) DNA variability (>40%), yet was less prevalent amongst early Neolithic farmers (~19%) and virtually absent in Mesolithic hunter-gatherers. To investigate this haplogroup’s significance in the maternal population history of Europeans we employed novel techniques such as DNA immortalization and hybridization-enrichment to sequence 39 hg H mt genomes from ancient human remains across a transect through time in Neolithic Central Europe. The results of our population genetic analyses reveal that the current patterns of diversity and distribution of hg H were largely established during the Mid-Neolithic, but with substantial genetic contributions from subsequent pan-European cultures such as the Bell Beakers, which expanded out of Iberia in the Late Neolithic (~2800 BC). Using a strict diachronic approach allowed us to reconcile ‘real-time’ genetic data from the most common European mtDNA hg with cultural changes that took place between the Early Neolithic (~5450 BC) and Bronze Age (~2200 BC) in Central Europe. This revealed the Late Neolithic (2800-2200 BC) as a dynamic period that profoundly shaped the genetic landscape of modern-day Europeans. Furthermore, linking ancient hg H genome sequences to specific points in time by using radiocarbon dates as tip calibrations allowed us to reconstruct a precise lineage history of hg H and to calculate a mutation rate 45% higher than traditional estimates based on the human/chimp split.
Preliminary research on hereditary features of Yinxu Population.
... The 37 individuals sampled in this study have been discovered in middle to small size burials, and therefore constitute a representative sample to study Yinxu commoners’ society. Mitochondrial DNA analysis showed that the Yinxu population included the haplogroups D, G, A, C, Z, M10, M*, B, F and N9a. According to the analysis of molecular variance, the distribution frequency and the rare published data, the Yinxu population shows a closest genetic affinity with the populations of Dadianzi and Zhukaigou early Bronze Age sites (Inner Mongolia), but a more distant relation to the historical period populations. The Yinxu population is also very similar to the modern northern Han Chinese. ... 

Investigating lactase persistence in a Medieval German cemetery: A step towards understanding the rise of the European lactase persistence polymorphism (-3910C/T).
Previous ancient DNA-based studies on the Neolithic found that the incidence of LP falls below detection levels in most regions. Our research shows that between the Neolithic and Medieval periods, the frequency of LP rose from near 0% to over 50%. Also, given that the frequency of LP genotypes in modern-day Germany is estimated at 78.5%, our results indicate that rather than being stable by the Medieval period, the lactase persistent genotype has continued to increase in frequency over the last 1000 years. This new evidence sheds light on the dynamic evolutionary history of the European lactase persistent trait and its global cultural implications.
 New Neanderthal remains from Kalamakia cave, Mani peninsula, Southern Greece.

Peeling back the layers: additional evidence for the date of the Petralona skull (Homo heidelbergensis), Greece.
,.. We conclude that there is no white sinter deposited directly on the skull and therefore the initial date of the skull given by Henning et al. and Grun’s revised date of ca. 200 ka are correct.
Analysis of archaic introgression in Ötzi the Tyrolean Iceman, a 5300 year-old prehistoric modern human.
... We carried out a series of comparisons to address these questions. By examining the Neandertal similarity of individuals from the 1000 Genomes Project, we have substantially expanded the sample of Neandertal-human comparisons. We also examined the genome of the Tyrolean Iceman, a European from approximately 5300 years ago. This is the first comparison of Neandertal genomes to the genome of a prehistoric modern human individual.
A quantitative approach for late Pleistocene hominin brain size.
... The results of our study show that Neanderthals have smaller brains than the Pleistocene AMH despite the fact that the latter are smaller in body mass. However, the Holocene AMH (7 populations) have smaller brain sizes than those of Neanderthals. ...
Re-evaluating the functional and adaptive significance of Neandertal nasofacial anatomy.
... Among Middle and Late Pleistocene Homo, there is evidence that nasal morphology varies with climate, albeit within an archaic architectural nasofacial framework. Neandertal internal nasal dimensions are greater in both height and length than archaic humans from sub-Saharan Africa. Furthermore, while other aspects of the nose are relatively broad, superior internal breadth dimensions in Neandertals are narrowed relative to sub-Saharan archaics. These differences parallel those seen in modern humans, indicating that Neandertals had an increased capacity for nasal heat and moisture exchange over their African counterparts and thus exhibit clear evidence for cold-climate adaptation.

Saturday, 16 February 2013

Ancient mtDNA and gene flow from Siberia to NE Europe

I had mentioned the thesis by the lead author, and now a paper from it has been published. If anyone notices any new material in the new paper, feel free to highlight it in the comments.

PLoS Genet 9(2): e1003296. doi:10.1371/journal.pgen.1003296

Ancient DNA Reveals Prehistoric Gene-Flow from Siberia in the Complex Human Population History of North East Europe

Clio Der Sarkissian et al.

North East Europe harbors a high diversity of cultures and languages, suggesting a complex genetic history. Archaeological, anthropological, and genetic research has revealed a series of influences from Western and Eastern Eurasia in the past. While genetic data from modern-day populations is commonly used to make inferences about their origins and past migrations, ancient DNA provides a powerful test of such hypotheses by giving a snapshot of the past genetic diversity. In order to better understand the dynamics that have shaped the gene pool of North East Europeans, we generated and analyzed 34 mitochondrial genotypes from the skeletal remains of three archaeological sites in northwest Russia. These sites were dated to the Mesolithic and the Early Metal Age (7,500 and 3,500 uncalibrated years Before Present). We applied a suite of population genetic analyses (principal component analysis, genetic distance mapping, haplotype sharing analyses) and compared past demographic models through coalescent simulations using Bayesian Serial SimCoal and Approximate Bayesian Computation. Comparisons of genetic data from ancient and modern-day populations revealed significant changes in the mitochondrial makeup of North East Europeans through time. Mesolithic foragers showed high frequencies and diversity of haplogroups U (U2e, U4, U5a), a pattern observed previously in European hunter-gatherers from Iberia to Scandinavia. In contrast, the presence of mitochondrial DNA haplogroups C, D, and Z in Early Metal Age individuals suggested discontinuity with Mesolithic hunter-gatherers and genetic influx from central/eastern Siberia. We identified remarkable genetic dissimilarities between prehistoric and modern-day North East Europeans/Saami, which suggests an important role of post-Mesolithic migrations from Western Europe and subsequent population replacement/extinctions. This work demonstrates how ancient DNA can improve our understanding of human population movements across Eurasia. It contributes to the description of the spatio-temporal distribution of mitochondrial diversity and will be of significance for future reconstructions of the history of Europeans.

Link

Thursday, 14 February 2013

Southeast Asian Neolithic dogs

From the paper:
Nevertheless, the close phylogenetic clustering of haplotypes from Thailand, Brunei, Bali, and the Philippines suggests these populations originated from the same source, consistent with a single migration event, whereas the dingoes, NGSDs, and dogs from Taiwan appear sufficiently distinct from these to reflect a distinct migration event (Fig. 2b-c). The clustering of the three Island Southeast Asian populations with Thailand also was more consistent with origination from Mainland Southeast Asia than Taiwan (in agreement with mtDNA findings of Oskarsson et al. 2011).
and:
In light of findings from the present study, it seems clear that both post-Victorian and Neolithic exchanges link eastern and western Eurasian dogs. However, the cause of post-Victorian haplotype sharing between Western breed dogs and Southeast Asian village dogs apparently reflects very recent introduction of Western dogs to the East rather than extraction of Eastern dogs to create Western breeds during the Victorian Era.
and:
Specifically, our aging of this European haplogroup to 5,800 (±SE = 1750) or 8,400 (±SE = 2500) years (depending on the dingo calibration to 3,500 or 5,000 years, respectively) suggests that the connection between pre-Victorian European and Southeast Asian dogs traces only to the Neolithic period and is not of sufficient antiquity to support the hypothesis of a single origin of dogs from Southeast Asia. Thus, although future studies are needed to combine the Y SNPs and STR markers in a geographically broader sampling of dogs than was considered here, our findings support the hypothesis for a massive Neolithic expansion of dogs from Southeast Asia rather than a Paleolithic origin of dogs from this region.

This massive Neolithic expansion of Southeast Asian dogs is testable by looking at early European dogs; these ought not to belong to haplogroup H1. It would also be interesting to speculate about the trade routes and/or population movements that facilitated the spread of dogs from SE Asia to Europe during the Neolithic.

Mol Biol Evol (2013) doi: 10.1093/molbev/mst027

Y chromosome analysis of dingoes and Southeast Asian village dogs suggests a Neolithic continental expansion from Southeast Asia followed by multiple Austronesian dispersals

Benjamin N. Sacks et al.

Dogs originated >14,000 BP, but the location(s) where they first arose is uncertain. The earliest archaeological evidence of ancient dogs was discovered in Europe and the Middle East, some 5–7 millennia before that from Southeast Asia. However, mitochondrial DNA analyses suggest that most modern dogs derive from Southeast Asia, which has fueled the controversial hypothesis that dog domestication originated in this region despite the lack of supporting archaeological evidence. We propose and investigate with Y chromosomes an alternative hypothesis for the proximate origins of dogs from Southeast Asia--a massive Neolithic expansion of dogs from this region that largely replaced more primitive dogs to the west and north. Previous attempts to test matrilineal findings with independent patrilineal markers have lacked the necessary genealogical resolution and mutation rate estimates. Here, we used Y chromosome genotypes, composed of 29 SNPs and 5 STRs, from 338 Australian dingoes, New Guinea singing dogs, and village dogs from Island Southeast Asia, along with modern European breed dogs, to estimate the evolutionary mutation rates of Y chromosome STRs based on calibration to the independently known age of the dingo population. Dingoes exhibited a unique haplogroup characterized by a single distinguishing SNP mutation and 14 STR haplotypes. The age of the European haplogroup was estimated to be only 1.7 times older than that of the dingo population, suggesting an origin during the Neolithic rather than the Paleolithic (as predicted by the Southeast Asian origins hypothesis). We hypothesize that isolation of Neolithic dogs from wolves in Southeast Asia was a key step accelerating their phenotypic transformation, enhancing their value in trade and as cargo, and enabling them to rapidly expand and replace more primitive dogs to the West. Our findings also suggest that dingoes could have arrived in Australia directly from Taiwan, independently of later dispersals of dogs through Thailand to Island Southeast Asia.

Link

Monday, 11 February 2013

Human mobility at the start of Balkan Neolithic

Link to press release.

PNAS doi: 10.1073/pnas.1211474110

Strontium isotopes document greater human mobility at the start of the Balkan Neolithic

Dušan Borić and T. Douglas Price

Questions about how farming and the Neolithic way of life spread across Europe have been hotly debated topics in archaeology for decades. For a very long time, two models have dominated the discussion: migrations of farming groups from southwestern Asia versus diffusion of domesticates and new ideas through the existing networks of local forager populations. New strontium isotope data from the Danube Gorges in the north-central Balkans, an area characterized by a rich burial record spanning the Mesolithic–Neolithic transition, show a significant increase in nonlocal individuals from ∼6200 calibrated B.C., with several waves of migrants into this region. These results are further enhanced by dietary evidence based on carbon and nitrogen isotopes and an increasingly high chronological resolution obtained on a large sample of directly dated individuals. This dataset provides robust evidence for a brief period of coexistence between indigenous groups and early farmers before farming communities absorbed the foragers completely in the first half of the sixth millennium B.C.

Link

Wednesday, 6 February 2013

Complex history of the olive tree

Proc. R. Soc. B 7 April 2013 vol. 280 no. 1756
doi: 10.1098/rspb.2012.2833

The complex history of the olive tree: from Late Quaternary diversification of Mediterranean lineages to primary domestication in the northern Levant

G. Besnard et al.

The location and timing of domestication of the olive tree, a key crop in Early Mediterranean societies, remain hotly debated. Here, we unravel the history of wild olives (oleasters), and then infer the primary origins of the domesticated olive. Phylogeography and Bayesian molecular dating analyses based on plastid genome profiling of 1263 oleasters and 534 cultivated genotypes reveal three main lineages of pre-Quaternary origin. Regional hotspots of plastid diversity, species distribution modelling and macrofossils support the existence of three long-term refugia; namely the Near East (including Cyprus), the Aegean area and the Strait of Gibraltar. These ancestral wild gene pools have provided the essential foundations for cultivated olive breeding. Comparison of the geographical pattern of plastid diversity between wild and cultivated olives indicates the cradle of first domestication in the northern Levant followed by dispersals across the Mediterranean basin in parallel with the expansion of civilizations and human exchanges in this part of the world.

Link

Wednesday, 23 January 2013

Dog food

Diet Shaped Dog Domestication
The analysis turned up 36 regions, with 122 genes in all, that may have contributed to dog evolution, the team reports online today in Nature. Nineteen of these regions contain genes important for the brain, eight of which are involved with nervous system development, which makes sense given the importance of behavioral changes in the transition to becoming man's best friend, Axelsson notes.

More surprising were genes for digesting starch. Dogs had four to 30 copies of the gene for amylase, a protein that starts the breakdown of starch in the intestine. Wolves have only two copies, one on each chromosome. As a result, that gene was 28-fold more active in dogs, the researchers found. More copies means more protein, and test-tube studies indicate that dogs should be fivefold better than wolves at digesting starch, the chief nutrient in agricultural grains such as wheat and rice. The number of copies of this gene also varies in people: Those eating high carbohydrate diets -- such as the Japanese and European Americans -- have more copies than people with starch-poor diets, such as the Mbuti in Africa. "We have adapted in a very similar way to the dramatic changes that happened when agriculture was developed," Axelsson says.
Nature (2013) doi:10.1038/nature11837

The genomic signature of dog domestication reveals adaptation to a starch-rich diet

Erik Axelsson et al.

The domestication of dogs was an important episode in the development of human civilization. The precise timing and location of this event is debated1, 2, 3, 4, 5 and little is known about the genetic changes that accompanied the transformation of ancient wolves into domestic dogs. Here we conduct whole-genome resequencing of dogs and wolves to identify 3.8 million genetic variants used to identify 36 genomic regions that probably represent targets for selection during dog domestication. Nineteen of these regions contain genes important in brain function, eight of which belong to nervous system development pathways and potentially underlie behavioural changes central to dog domestication6. Ten genes with key roles in starch digestion and fat metabolism also show signals of selection. We identify candidate mutations in key genes and provide functional support for an increased starch digestion in dogs relative to wolves. Our results indicate that novel adaptations allowing the early ancestors of modern dogs to thrive on a diet rich in starch, relative to the carnivorous diet of wolves, constituted a crucial step in the early domestication of dogs.

Link

Tuesday, 24 August 2004

Y chromosomal haplogroup J as a signature of the post-neolithic colonization of Europe

A very important new paper about Y chromosome haplogroup J. I will have more to say once I have finished reading it carefully.

Update:
The main finding of the authors is that haplogroup J was not carried by a single advance from the Middle East into Europe. Rather, at least two expansions can be detected, a "Neolithic" one and a "Greek" one:

In summary, our data are in agreement with a major discontinuity for the peopling of southern Europe. Here, haplogroup J constitutes not only the signature of a single wave-of-advance from the Levant but, to a greater extent, also of the expansion of the Greek world, with an accompanying novel quota of genetic variation produced during its demographic growth. In the analysis by Cavalli-Sforza et al. (1994), the two peopling contributions can be distinguished, as they are caught in the first and the fourth principal component, respectively, but the relevance of the latter may have been underestimated. The two processes, widely spaced in time, are associated with dramatically different travel technologies. This implies that, in the central and west Mediterranean, the entry of J chromosomes may have occurred mainly by sea, i.e., in the south–east of both Spain and Italy.

Human Genetics
(online first)

Y chromosomal haplogroup J as a signature of the post-neolithic colonization of Europe
F. Di Giacomo et al.

Abstract In order to attain a finer reconstruction of the peopling of southern and central-eastern Europe from the Levant, we determined the frequencies of eight lineages internal to the Y chromosomal haplogroup J, defined by biallelic markers, in 22 population samples obtained with a fine-grained sampling scheme. Our results partially resolve a major multifurcation of lineages within the haplogroup. Analyses of molecular variance show that the area covered by haplogroup J dispersal is characterized by a significant degree of molecular radiation for unique event polymorphisms within the haplogroup, with a higher incidence of the most derived sub-haplogroups on the northern Mediterranean coast, from Turkey westward; here, J diversity is not simply a subset of that present in the area in which this haplogroup first originated. Dating estimates, based on simple tandem repeat loci (STR) diversity within each lineage, confirmed the presence of a major population structuring at the time of spread of haplogroup J in Europe and a punctuation in the peopling of this continent in the post-Neolithic, compatible with the expansion of the Greek world. We also present here, for the first time, a novel method for comparative dating of lineages, free of assumptions of STR mutation rates.

Link

Tuesday, 17 August 2004

Ancient DNA of Neolithic skeleton from NE Siberia

A skeleton from northeastern Yakutia (east Siberia) dating to the Neolithic period (3,600 years BP) belongs to mtDNA haplogroup C and the combined mtDNA and autosomal analysis shows its similarity to modern east Siberian/Native American populations.

American Journal of Physical Anthropology (Early View)

Ancient DNA analysis of human Neolithic remains found in northeastern Siberia
François-Xavier Ricaut et al.

ABSTRACT

We successfully extracted DNA from a bone sample of a Neolithic skeleton (dated 3,600 ± 60 years BP) excavated in northeastern Yakutia (east Siberia). Ancient DNA was analyzed by autosomal STRs (short tandem repeats) and by sequencing of the hypervariable region I (HV1) of the mitochondrial DNA (mtDNA) control region. The STR profile, the mitochondrial haplotype, and the haplogroup determined were compared with those of modern Eurasian and Native American populations. The results showed the affinity of this ancient skeleton with both east Siberian/Asian and Native American populations.
Link

Thursday, 5 August 2004

mtDNA analysis of Neolithic Siberians

This study shows that modern Siberians are partly descended from the Mongoloid Neolithic Siberians.

Anthropol Anz. 1998 Mar;56(1):1-6.

Siberian population of the New Stone Age: mtDNA haplotype diversity in the ancient population from the Ust'-Ida I burial ground, dated 4020-3210 BC by 14C.
Naumova O Y et al.

On the basis of analysis of mtDNA from skeletal remains, dated by 14C 4020-3210 BC, from the Ust'-Ida I Neolithic burial ground in Cis-Baikal area of Siberia, we obtained genetic characteristics of the ancient Mongoloid population. Using the 7 restriction enzymes for the analysis of site's polymorphism in 16,106-16,545 region of mtDNA, we studied the structure of the most frequent DNA haplotypes, and estimated the intrapopulational nucleotide diversity of the Neolithic population. Comparison of the Neolithic and modern indigeneous populations from Siberia, Mongolia and Ural showed, that the ancient Siberian population is one of the ancestors of the modern population of Siberia. From genetic distance, in the assumption of constant nucleotide substitution rate, we estimated the divergence time between the Neolithic and the modern Siberian population. This divergence time (5572 years ago) is conformed to the age of skeletal remains (5542-5652 years). With use of the 14C dates of the skeletal remains, nucleotide substitution rate in mtDNA was estimated as 1% sequence divergence for 8938-9115 years.


Link