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Metazoan phylogeny remains one of evolutionary biology''s major unsolved problems. Molecular and morphological data, as well as different analytical approaches, have produced highly conflicting results due to homoplasy resulting from more than 570 million years of evolution . To date, parsimony has been the only feasible combined approach but is highly sensitive to long-branch attraction . Recent development of stochastic models for discrete morphological characters and computationally efficient methods for Bayesian inference has enabled combined molecular and morphological data analysis with rigorous statistical approaches less prone to such inconsistencies . We present the first statistically founded analysis of a metazoan data set based on a combination of morphological and molecular data and compare the results with a traditional parsimony analysis. Interestingly, the Bayesian analyses demonstrate a high degree of congruence between morphological and molecular data, and both data sets contribute to the result of the combined analysis. Additionally, they resolve several irregularities obtained in previous studies and show high credibility values for controversial groups such as the ecdysozoans and lophotrochozoans. Parsimony, on the contrary, shows conflicting results, with morphology being congruent to the Bayesian results and the molecular data set producing peculiarities that are largely reflected in the combined analysis. [Copyright &y& Elsevier]

Owing to their constant low temperatures, glacial ice and permafrost might contain the oldest nucleic acids and microbial cells on Earth, which could prove key to reconstructing past ecosystems and for the planning of missions to other planets. However, recent claims concerning viable cells and microbial nucleic acids obtained from ice- and permafrost cores from hundreds of thousands to millions of years old are not properly authenticated and the findings could be the result of contamination. Here, we discuss the processes that restrict the long-term survival of DNA and/or RNA molecules in ice and permafrost, and highlight sources of contamination that could result in false claims. Additionally, we present a set of precautions, controls and criteria to help ensure that future cultures and sequences are authentic. [Copyright &y& Elsevier]

Genetic analyses of permafrost and temperate sediments reveal that plant and animal DMA may be preserved for long periods, even in the absence of obvious macrofossils. In Siberia, five permafrost cores ranging from 400,000 to 10,000 years old contained at least 19 different plant taxa, including the oldest authenticated ancient DMA sequences known, and megafaunal sequences including mammoth, bison, and horse. The genetic data record a number of dramatic changes in the taxonomic diversity and composition of Beringian vegetation and fauna. Temperate cave sediments in New Zealand also yielded DNA sequences of extinct biota, including two species of ratite moa, and 29 plant taxa characteristic of the prehuman environment. Therefore, many sedimentary deposits may contain unique, and widespread, genetic records of paleoenvironments. [ABSTRACT FROM AUTHOR]

Abstract Empirical investigations of intraspecific outbreeding and subsequent introgressive hybridization in natural populations are rare, particularly among conspecific populations of large mammals. Using mitochondrial DNA data [partial control region (496 basepairs — bp) and cytochrome b gene (343 bp) sequences analysed from 95 individuals representing 17 sampling locations scattered through the African miombo (Brachystegia ) woodland ecosystem] and phylogeographical statistical procedures (gene genealogy, nested cladistic and admixture proportion analyses), we (i) give a detailed dissection of the geographical genetic structure of Hippotragus niger ; (ii) infer the processes and events potentially involved in the population history; and (iii) trace extensive introgressive hybridization in the species. The present-day sable antelope population shows a tripartite pattern of genetic subdivision representing West Tanzanian, Kenya/East Tanzanian and Southern Africa locations. Nested clade analysis revealed that past allopatric fragmentation, caused probably by habitat discontinuities associated with the East African Rift Valley system, together with intermediary episodic long-distance colonization and restricted, recurrent gene flow have played an predominant role in shaping the extent of maternal genetic diversity (10.4%) and population structure. An extensive (average rate of admixture = 20.0%), but geographically circumscribed and unidirectional hybridization event in the past was inferred, resulting in an extreme (the highest discovered so far in mammals) intraspecific difference of 18.2% among morphologically monotypic sable antelopes from West Tanzania. The results are used to provide an evolutionary framework within which taxonomic implications and conservation decisions can be evaluated. [ABSTRACT FROM AUTHOR]

Studies the diversity of eukaryotic fungi, plants, algae and protists in fossil glacier ice. Materials and methods of the study; Results and discussion.

Premise: Cultivation and naturalization of plants beyond their natural range can bring previously geographically isolated taxa together, increasing the opportunity for hybridization, the outcomes of which are not predictable. Here, we explored the phenotypic and genomic effects of interspecific gene flow following the widespread cultivation of Mentha spicata (spearmint), M. longifolia, and M. suaveolens. Methods: We morphologically evaluated 155 herbarium specimens of three Mentha species and sequenced the genomes of a subset of 93 specimens. We analyzed the whole genomes in a population and the phylogenetic framework and associated genomic classifications in conjunction with the morphological assessments. Results: The allopolyploid M. spicata, which likely evolved in cultivation, had altered trichome characters, that is possibly a product of human selection for a more palatable plant or a byproduct of selection for essential oils. There were signs of genetic admixture between mints, including allopolyploids, indicating that the reproductive barriers between Mentha species with differences in ploidy are likely incomplete. Still, despite gene flow between species, we found that genetic variants associated with the cultivated trichome morphology continue to segregate. Conclusions: Although hybridization, allopolyploidization, and human selection during cultivation can increase species richness (e.g., by forming hybrid taxa), we showed that unless reproductive barriers are strong, these processes can also result in mixing of genes between species and the potential loss of natural biodiversity. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor regarding an article which was published in the May 24, 2003 issue of 'The Lancet.' How the article discussed the idea that many microbial bacteria and viruses found on Earth could have extraterrestrial origins.

Aim: In this study, we assessed the importance of local‐ to landscape‐scale effects of land cover and land use on flying insect biomass. Location: Denmark and parts of Germany. Methods: We used rooftop‐mounted car nets in a citizen science project ("InsectMobile") to allow for large‐scale geographic sampling of flying insects. Volunteers sampled insects along 278 five‐km routes in urban, farmland, grassland, wetland and forest landscapes in the summer of 2018. The bulk insect samples were dried overnight to obtain the sample biomass. We extracted proportional land use variables in buffers between 50 and 1,000 m along the routes and compiled them into land cover categories to examine the effect of each land cover, and specific land use types, on insect biomass. Results: We found a negative association between urban cover and flying insect biomass (1% increase in urban cover = 1% [95% CI: −3.0 to 0.0] decrease in biomass in Denmark, and a 3% [95% CI: −3.0 to 0.0] decrease in Germany) at a landscape scale (1,000‐m buffer). In Denmark, we also found positive effects of semi‐natural land cover types, that is protected grassland (largest at the landscape scale, 1000 m) and forests (largest at intermediate scales, 250 m). Protected grassland cover had a stronger positive effect on insect biomass than forest cover did. For farmland cover, the positive association with insect biomass was not clearly modified by any variable associated with farmland use intensity. The negative association between insect biomass and urban land cover appeared to be reduced by increased urban green space. Main conclusions: Our results show that land cover has an impact on flying insect biomass with the magnitude of this effect varying across spatial scales. However, the vast expanse of grey space in urbanized areas has a direct negative impact on flying insect biomass across all spatial scales examined. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the early-life development of the skin microbiome in atopic dermatitis. Nineteen infants with atopic dermatitis and 19 healthy infants were evaluated 3 times, at 3 months intervals, within the first 30 months of life. Tape-strips were collected from volar forearms, cheeks, and eczema lesions, and the skin microbiome was assessed by 16S rRNA sequencing. Both the community structure and richness of the skin microbiome of infants with atopic dermatitis differed significantly from that of healthy infants, with greater richness in healthy infants. For infants with atopic dermatitis, the community composition was not dominated by Staphylococci. For healthy infants, community composition and richness correlated significantly with age, while such a pattern was not revealed in infants with atopic dermatitis. This suggests a slower maturation of the skin microbiome in atopic dermatitis, which precedes the staphylococcal predominance observed in older children and adults. [ABSTRACT FROM AUTHOR]

Migration allows animals to exploit spatially separated and seasonally available resources at a continental to global scale. However, responding to global climatic changes might prove challenging, especially for long-distance intercontinental migrants. During glacial periods, when conditions became too harsh for breeding in the north, avian migrants have been hypothesized to retract their distribution to reside within small refugial areas. Here, we present data showing that an Afro-Palearctic migrant continued seasonal migration, largely within Africa, during previous glacial-interglacial cycles with no obvious impact on population size. Using individual migratory track data to hindcast monthly bioclimatic habitat availability maps through the last 120,000 y, we show altered seasonal use of suitable areas through time. Independently derived effective population sizes indicate a growing population through the last 40,000 y. We conclude that the migratory lifestyle enabled adaptation to shifting climate conditions. This indicates that populations of resource-tracking, longdistance migratory species could expand successfully during warming periods in the past, which could also be the case under future climate scenarios. [ABSTRACT FROM AUTHOR]

Studies the characterization of genetic miscoding lesions caused by postmortem damage. Key issues of interest; Analysis of pertinent topics and relevant issues; Implications on human genetics.

Late Quaternary climatic fluctuations in the Northern Hemisphere had drastic effects on large mammal species, leading to the extinction of a substantial number of them. The giant deer (Megaloceros giganteus) was one of the species that became extinct in the Holocene, around 7660 calendar years before present. In the Late Pleistocene, the species ranged from western Europe to central Asia. However, during the Holocene, its range contracted to eastern Europe and western Siberia, where the last populations of the species occurred. Here, we generated 35 Late Pleistocene and Holocene giant deer mitogenomes to explore the genetics of the demise of this iconic species. Bayesian phylogenetic analyses of the mitogenomes suggested five main clades for the species: three pre-Last Glacial Maximum clades that did not appear in the post-Last Glacial Maximum genetic pool, and two clades that showed continuity into the Holocene. Our study also identified a decrease in genetic diversity starting in Marine Isotope Stage 3 and accelerating during the Last Glacial Maximum. This reduction in genetic diversity during the Last Glacial Maximum, coupled with a major contraction of fossil occurrences, suggests that climate was a major driver in the dynamics of the giant deer. [ABSTRACT FROM AUTHOR]

The study of South American camelids and their domestication is a highly debated topic in zooarchaeology. Identifying the domestic species (alpaca and llama) in archaeological sites based solely on morphological data is challenging due to their similarity with respect to their wild ancestors. Using genetic methods also presents challenges due to the hybridization history of the domestic species, which are thought to have extensively hybridized following the Spanish conquest of South America that resulted in camelids slaughtered en masse. In this study, we generated mitochondrial genomes for 61 ancient South American camelids dated between 3,500 and 2,400 years before the present (Early Formative period) from two archaeological sites in Northern Chile (Tulán-54 and Tulán-85), as well as 66 modern camelid mitogenomes and 815 modern mitochondrial control region sequences from across South America. In addition, we performed osteometric analyses to differentiate big and small body size camelids. A comparative analysis of these data suggests that a substantial proportion of the ancient vicuña genetic variation has been lost since the Early Formative period, as it is not present in modern specimens. Moreover, we propose a domestication hypothesis that includes an ancient guanaco population that no longer exists. Finally, we find evidence that interbreeding practices were widespread during the domestication process by the early camelid herders in the Atacama during the Early Formative period and predating the Spanish conquest. [ABSTRACT FROM AUTHOR]

The Lund collection is one of the oldest subfossil collections in the world. The vast assemblage of subfossils was collected in the 1830s and 1840s by Peter Wilhelm Lund in Lagoa Santa, Brazil, and was shipped to Copenhagen in 1848, where it was stored in various locations around the city with little attention for the future preservation of the collection. So far, successful genetic research on the material collected by Lund has been limited to two samples of human petrous bone. However, less is known about the preservation conditions of the vast amounts of small and fragmentary bones stored in the collection. To address this, we studied ancient DNA from bulk bone samples of approximately 100 bone fragments from the P.W. Lund collection from boxes with varying degrees of physical preservation conditions. Using bulk bone metabarcoding, we found a high species diversity in all samples. In total, we identified 17 species, representing 11 mammals, two birds, one fish, and three frogs. Of these, two species are new to the collection. Collectively, these results exhibit the potential of future genetic studies on the famous P.W. Lund collection and suggest that the effects of poor storage conditions are probably negligible compared with the long‐term in situ degradation that specimens undergo before excavation. [ABSTRACT FROM AUTHOR]

For at least 9000 years dogs have been pulling sleds across the Arctic, facilitating subsistence strategies and migrations. Despite the enduring presence of dogs in the Arctic there is an absence of comprehensive studies of the material culture associate with dog sledding, including the diverse technical elements needed for the activity. This study proposes a framework for the recognition of reliable archaeological indicators of dog sledding. The outcome is based on comparisons between ethnographic information of the dog traction technology and archaeological sites from the Arctic regions of Siberia, Alaska, Canada, and Greenland using multivariate analysis. These sites were selected as case studies to encompass the breadth of geographical and Inuit cultural diversity where dog sledding traditionally has been practiced. We argue, that by using this framework it is possible to study dog sledding in the Arctic prior to the Thule Inuit period and gain more knowledge about the origin of the practice. By combining sources from ethnography, history and archaeology, our framework identified items involved in dog sledding that were universal to the practice as well as items that were regionally specific. However, the most reliable evidence for dog sledding is the presence of both sled parts, dog bones and equipment for harnessing the dogs. [Display omitted] • Ethnographic framework reveals reliable indicators for identifying dog sledding on archaeological sites through material evidence. • Determining universal and regionally specific indicators of dog sledding on prehistoric archaeological sites. • Providing a method for reexamining early archaeological sites to identify previously overlooked evidence for dog traction. [ABSTRACT FROM AUTHOR]

North America is currently home to a number of grey wolf (Canis lupus) and wolf-like canid populations, including the coyote (Canis latrans) and the taxonomically controversial red, Eastern timber and Great Lakes wolves. We explored their population structure and regional gene flow using a dataset of 40 full genome sequences that represent the extant diversity of North American wolves and wolf-like canid populations. This included 15 new genomes (13 North American grey wolves, 1 red wolf and 1 Eastern timber/Great Lakes wolf), ranging from 0.4 to 15x coverage. In addition to providing full genome support for the previously proposed coyote-wolf admixture origin for the taxonomically controversial red, Eastern timber and Great Lakes wolves, the discriminatory power offered by our dataset suggests all North American grey wolves, including the Mexican form, are monophyletic, and thus share a common ancestor to the exclusion of all other wolves. Furthermore, we identify three distinct populations in the high arctic, one being a previously unidentified “Polar wolf” population endemic to Ellesmere Island and Greenland. Genetic diversity analyses reveal particularly high inbreeding and low heterozygosity in these Polar wolves, consistent with long-term isolation from the other North American wolves. [ABSTRACT FROM AUTHOR]

1. Species richness is unrivalled as the most reported biodiversity metric in ecological and conservation research. Unfortunately, species richness ignores the scale-dependency of biodiversity. 2. We propose the metric uniquity , a quantitative and spatially scalable measure of uniqueness of a site based on a species-by-site matrix and a site-by-habitat type classification with area weights for habitat types correcting for sampling biases. 3. An example of uniquity is presented using vascular plant data from 130 sites representing a larger region (Denmark). We demonstrate the importance of the scale parameter of uniquity for the prediction of independent uniqueness indices calculated from species distribution data and the number of recorded red listed species. 4. We compare the performance of uniquity with the performance of the indices Local Contribution to Beta Diversity (LCBD) and Range Rarity Richness (RRR), and we investigate its sensitivity to small sample size and poorly resolved habitat classification. 5. We assess the performance of the uniquity metric applied to DNA metabarcoding data for plants, fungi and eukaryotes from the same set of study sites. 6. Uniquity is a strong predictor of site uniqueness based on national distribution data and also correlates neatly with the observed number of red listed species. Uniquity based on DNA metabarcoding corresponds well with the number of red listed species observed. 7. Perspective: Uniquity is generally applicable to biotas sampled with comparable effort, including field inventories, trap sampling, and DNA metabarcoding data. To our knowledge uniquity is the first index of uniqueness that explicitly considers spatial scale and sampling biases, while simultaneously accepting non-annotated DNA-data as input. Based on our study we offer general recommendations for further use and testing of uniquity as conservation value metric. [ABSTRACT FROM AUTHOR]

New Zealand's geographic isolation, lack of native terrestrial mammals, and Gondwanan origins make it an ideal location to study evolutionary processes. However, since the archipelago was first settled by humans 750 y ago, its unique biodiversity has been under pressure, and today an estimated 49% of the terrestrial avifauna is extinct. Current efforts to conserve the remaining fauna rely on a better understanding of the composition of past ecosystems, as well as the causes and timing of past extinctions. The exact temporal and spatial dynamics of New Zealand's extinct fauna, however, can be difficult to interpret, as only a small proportion of animals are preserved as morphologically identifiable fossils. Here, we conduct a large-scale genetic survey of subfossil bone assemblages to elucidate the impact of humans on the environment in New Zealand. By genetically identifying more than 5,000 nondiagnostic bone fragments from archaeological and paleontological sites, we reconstruct a rich faunal record of 110 species of birds, fish, reptiles, amphibians, and marine mammals. We report evidence of five whale species rarely reported from New Zealand archaeological middens and characterize extinct lineages of leiopelmatid frog (Leiopelma sp.) and kākāpō (Strigops habroptilus) haplotypes lost from the gene pool. Taken together, this molecular audit of New Zealand's subfossil record not only contributes to our understanding of past biodiversity and precontact Māori subsistence practices but also provides a more nuanced snapshot of anthropogenic impacts on native fauna after first human arrival. [ABSTRACT FROM AUTHOR]

Human parvovirus B19 (B19V) is a ubiquitous human pathogen associated with a number of conditions, such as fifth disease in children and arthritis and arthralgias in adults. B19V is thought to evolve exceptionally rapidly among DNA viruses, with substitution rates previously estimated to be closer to those typical of RNA viruses. On the basis of genetic sequences up to ~70 years of age, the most recent common ancestor of all B19V has been dated to the early 1800s, and it has been suggested that genotype 1, the most common B19V genotype, only started circulating in the 1960s. Here we present 10 genomes (63.9-99.7% genome coverage) of B19V from dental and skeletal remains of individuals who lived in Eurasia and Greenland from ~0.5 to ~6.9 thousand years ago (kya). In a phylogenetic analysis, five of the ancient B19V sequences fall within or basal to the modern genotype 1, and five fall basal to genotype 2, showing a long-term association of B19V with humans. The most recent common ancestor of all B19V is placed ~12.6 kya, and we find a substitution rate that is an order of magnitude lower than inferred previously. Further, we are able to date the recombination event between genotypes 1 and 3 that formed genotype 2 to ~5.0-6.8 kya. This study emphasizes the importance of ancient viral sequences for our understanding of virus evolution and phylogenetics. [ABSTRACT FROM AUTHOR]

The ethnic groups that inhabit the mountainous Dir and Swat districts of northern Pakistan are marked by high levels of cultural and phenotypic diversity. To obtain knowledge of the extent of genetic diversity in this region, we investigated Y-chromosomal diversity in five population samples representing the three main ethnic groups residing within these districts, including Gujars, Pashtuns and Kohistanis. A total of 27 Y-chromosomal short tandem repeats (Y-STRs) and 331 Y-chromosomal single nucleotide polymorphisms (Y-SNPs) were investigated. In the Y-STRs, we observed very high and significant levels of genetic differentiation in nine of the 10 pairwise between-group comparisons ( RST 0.179-0.746), and the differences were mirrored in the Y-SNP haplogroup frequency distribution. No genetic differences were found between the two Pashtun subethnic groups Tarklanis and Yusafzais ( RST = 0.000). Utmankhels, also considered Pashtuns culturally, were not closely related to any of the other population samples ( RST 0.451-0.746). Thus, our findings provide examples of both associations and dissociations between cultural and genetic legacies. When analyzed within a larger continental-scale context, these five ethnic groups fall mostly outside the previously characterized Y-chromosomal gene pools of the Indo-Pakistani subcontinent. Male founder effects, coupled with culturally and topographically based constraints upon marriage and movement, are likely responsible for the high degree of genetic structure in this region. [ABSTRACT FROM AUTHOR]

Background: An increasing number of studies are addressing the evolutionary genomics of dog domestication, principally through resequencing dog, wolf and related canid genomes. There is, however, only one de novo assembled canid genome currently available against which to map such data - that of a boxer dog (Canis lupus familiaris). We generated the first de novo wolf genome (Canis lupus lupus) as an additional choice of reference, and explored what implications may arise when previously published dog and wolf resequencing data are remapped to this reference. Results: Reassuringly, we find that regardless of the reference genome choice, most evolutionary genomic analyses yield qualitatively similar results, including those exploring the structure between the wolves and dogs using admixture and principal component analysis. However, we do observe differences in the genomic coverage of re-mapped samples, the number of variants discovered, and heterozygosity estimates of the samples. Conclusion: In conclusion, the choice of reference is dictated by the aims of the study being undertaken; if the study focuses on the differences between the different dog breeds or the fine structure among dogs, then using the boxer reference genome is appropriate, but if the aim of the study is to look at the variation within wolves and their relationships to dogs, then there are clear benefits to using the de novo assembled wolf reference genome. [ABSTRACT FROM AUTHOR]

Focuses on contamination in the draft of the human genome masquerades as lateral gene transfer. Transfer of bacterial genes; Prokaryotic DNA sequences.

The past decade has witnessed a revolution in ancient DNA (aDNA) research. Although the field's focus was previously limited to mitochondrial DNA and a few nuclear markers, whole genome sequences from the deep past can now be retrieved. This breakthrough is tightly connected to the massive sequence throughput of next generation sequencing platforms and the ability to target short and degraded DNA molecules. Many ancient specimens previously unsuitable for DNA analyses because of extensive degradation can now successfully be used as source materials. Additionally, the analytical power obtained by increasing the number of sequence reads to billions effectively means that contamination issues that have haunted aDNA research for decades, particularly in human studies, can now be efficiently and confidently quantified. At present, whole genomes have been sequenced from ancient anatomically modern humans, archaic hominins, ancient pathogens and megafaunal species. Those have revealed important functional and phenotypic information, as well as unexpected adaptation, migration and admixture patterns. As such, the field of aDNA has entered the new era of genomics and has provided valuable information when testing specific hypotheses related to the past. [ABSTRACT FROM AUTHOR]

DNA obtained from environmental samples such as sediments, ice or water (environmental DNA, eDNA), represents an important source of information on past and present biodiversity. It has revealed an ancient forest in Greenland, extended by several thousand years the survival dates for mainland woolly mammoth in Alaska, and pushed back the dates for spruce survival in Scandinavian ice-free refugia during the last glaciation. More recently, eDNA was used to uncover the past 50 000 years of vegetation history in the Arctic, revealing massive vegetation turnover at the Pleistocene/Holocene transition, with implications for the extinction of megafauna. Furthermore, eDNA can reflect the biodiversity of extant flora and fauna, both qualitatively and quantitatively, allowing detection of rare species. As such, trace studies of plant and vertebrate DNAin the environment have revolutionized our knowledge of biogeography. However, the approach remains marred by biases related toDNAbehaviour in environmental settings, incomplete reference databases and false positive results due to contamination.We provide a review of the field. [ABSTRACT FROM AUTHOR]

A novel human protoparvovirus related to human bufavirus and preliminarily named cutavirus has been discovered. We detected cutavirus in a sample of cutaneous malignant melanoma by using viral enrichment and high-throughput sequencing. The role of cutaviruses in cutaneous cancers remains to be investigated. [ABSTRACT FROM AUTHOR]

To date, the field of ancient DNA has relied almost exclusively on mitochondrial DNA (mtDNA) sequences. However, a number of recent studies have reported the successful recovery of anciet nuclear DNA (nuDNA) sequences, thereby allowing the characterization of genetic loci directly involved in phenotypic traits of extinct taxa. It is well documented that postmortem damage in ancient mtDNA can lead to the generation of artifactual sequences. However, as yet no one has thoroughly investigated the damage spectrum in ancient nuDNA. By comparing clone sequences from 23 fossil specimens, recovered from environments ranging from permafrost to desert, we demonstrate the presence of miscoding lesion damage in both the mtDNA and nuDNA, resulting in insertion of erroneous bases during amplification. Interestingly, no significant differences in the frequency of miscoding lesion damage are recorded between mtDNA and nuDNA despite great differences in cellular copy numbers. For both mtDNA and nuDNA, we find significant positive correlations between total sequence heterogeneity and the rates of type 1 transitions (adenine ↵ guanine and thymine ↵ cytosine) and type 2 transitions (cytosine ↵ thymine and guanine ↵ adenine), respectively. Type 2 transitions are by far the most dominant and increase relative to those of type 1 with damage load. The results suggest that the deamination of cytosine (and 5-methyl cytosine) to uracil (and thymine) is the main cause of miscoding lesions in both ancient mtDNA and nuDNA sequences. We argue that the problems presented by postmortem damage, as well as problems with contamination from exogenous sources of conserved nuclear genes, allelic variation, and the reliance on single nucleotide polymorphisms, call for great caution in studies relying on ancient nuDNA sequences. [ABSTRACT FROM AUTHOR]

One of Denmark's earliest Christian cemeteries is Kongemarken, dating to around AD 1000-1250. A feature of early Scandinavian Christian cemeteries is sex segregation, with females buried on the northern sides and males on the southern sides. However, such separation was never complete; in the few early Christian cemeteries excavated in Scandinavia, there were always a few males placed on the north side, and some females on the south side. At Kongemarken, several males with juxtaposed females were found on the north side of the cemetery. Thus, to evaluate possible kinship relationships, and more general questions of population affinity, we analyzed mitochondrial DNA extracted from nine individuals excavated in two different areas within the cemetery: one male and four females from Area 1, and one male and three females from Area 2. Using stringent laboratory protocols, each individual was unequivocally assigned to a mitochondrial haplogroup. A surprising amount of haplogroup diversity was observed (Area 1:1 U7 (male), 1 H, 1 I, 1 J, and 1 T2; Area 2:2 H, 1 I, and 1 T, with one H being male); even the three subjects of haplogroup H were of different subtypes. This indicates that no subjects within each area were maternally related. The observed haplogroup, U7, while common in India and in western Siberian tribes, was not previously observed among present-day ethnic Scandinavians, and haplogroup I is rare (2%) in Scandinavia. These observations suggest that the individuals living in the Roskilde region 1,000 years ago were not all members of a tightly knit local population and comprised individuals with genetic links with populations that were from much farther away. [ABSTRACT FROM AUTHOR]

Abstract: The majority of ancient DNA studies on human specimens have utilised teeth and bone as a source of genetic material. In this study the levels of endogenous contamination (i.e. present within the sample prior to sampling for the DNA analysis) are assessed within human bone and teeth specimens sampled from the cemetery of Santa Lucia alle Malve, Matera, Italy. This site is of exceptional interest, because the samples have been assayed for 18 measures of biochemical and physical preservation, and it is the only one identified in a study of more than 107 animal and 154 human bones from 43 sites across Europe, where a significant number of human bones was well preserved. The findings demonstrate several important issues: (a) although teeth are more resilient to contamination than bone, both are readily contaminated (presumably through handling or washing), and (b) once contaminated in this way, both are difficult (if not impossible) to decontaminate. Furthermore, although assessed on bone samples, several of the specific biochemical and physical characteristics that describe overall sample preservation, levels of microbial attack and related increases in sample porosity directly correlate with the presence of observable contamination in both bone and teeth samples from individual samples. While we can only speculate on the cause of this relationship, we posit that they provide useful guides for the assessment of whether samples are likely to be contaminated or not. [Copyright &y& Elsevier]

The diversity of fungi in permanently frozen soil from northeastern Siberia was studied by culture-independent PCR amplification of diverse environmental 18S rRNA genes. Elaborate protocols to avoid contamination during drilling, sampling, and amplification were used. A broad diversity of eukaryotic DNA sequences that were 510 bp long, including sequences of various fungi, plants, and invertebrates, could be obtained reproducibly from samples that were up to 300,000 to 400,000 years old. The sequences revealed that ancient fungal communities included a diversity of cold-adapted yeasts, dark-pigmented fungi, plant-parasitic fungi, and lichen mycobionts. DNA traces of tree-associated macrofungi in a modern tundra sample indicated that there was a shift in fungal diversity following the last ice age and supported recent results showing that there was a severe change in the plant composition in northeastern Siberia during this period. Interestingly, DNA sequences with high homology to sequences of coprophilic and keratinophilic fungi indicated that feces, hair, skin, and nails could have been sources of ancient megafauna DNA recently reported to be present in small amounts of Siberian permafrost sediments. [ABSTRACT FROM AUTHOR]

The widespread extinctions of large mammals at the end of the Pleistocene epoch have often been attributed to the depredations of humans; here we present genetic evidence that questions this assumption. We used ancient DNA and Bayesian techniques to reconstruct a detailed genetic history of bison throughout the late Pleistocene and Holocene epochs. Our analyses depict a large diverse population living throughout Beringia until around 37,000 years before the present, when the population's genetic diversity began to decline dramatically. The timing of this decline correlates with environmental changes associated with the onset of the last glacial cycle, whereas archaeological evidence does not support the presence of large populations of humans in Eastern Beringia until more than 15,000 years later. [ABSTRACT FROM AUTHOR]

Traces the genetic origins of islanders in the Andaman archipelago, which lies in an arc between Burma and Indonesia in the Bay of Bengal. Key issues of interest; Analysis of pertinent topics and relevant issues; Implications on human genetics.

Studies the distribution patterns of postmortem damage in human mitochondrial DNA. Key issues of interest; Analysis of pertinent topics and relevant issues; Implications on human genetics.

• Genetic and stable isotope analyses of fur clothing from the Arctic. • Excellent preservation of endogenous mitochondrial DNA. • Genetic and macroscopic species identifications were inconsistent in a third of the sampled garments. • Stable isotope analysis revealed diversity of dog diets across the Arctic. Among Indigenous populations of the Arctic, domestic dogs (Canislupus familiaris) were social actors aiding in traction and subsistence activities. Less commonly, dogs fulfilled a fur-bearing role in both the North American and Siberian Arctic. Examples of garments featuring dog skins were collected during the 19th-20th centuries and are now curated by the National Museum of Denmark. We sequenced the mitochondrial genomes of macroscopically identified dog skin garments. We conducted stable carbon and nitrogen isotope ratio analysis of the dog furs and of fur samples from contemporaneous pelts of Arctic (C. lupus arctos) and grey (C. lupus) wolves. Despite the presence of biocides used to protect the fur clothing during storage, we extracted well-preserved DNA using a minimally-invasive sampling protocol. Unexpectedly, the mtDNA genomes of one-third of the samples were consistent with wild taxa, rather than domestic dogs. The strong marine component in the diets of North American dogs distinguished them from Greenland and Canadian wolves, but Siberian dogs consumed diets that were isotopically similar to wild species. We found that dog provisioning practices were variable across the Siberian and North American Arctic, but in all cases, involved considerable human labor. [ABSTRACT FROM AUTHOR]