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1.
Nature ; 607(7918): 313-320, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35768506

RESUMO

The grey wolf (Canis lupus) was the first species to give rise to a domestic population, and they remained widespread throughout the last Ice Age when many other large mammal species went extinct. Little is known, however, about the history and possible extinction of past wolf populations or when and where the wolf progenitors of the present-day dog lineage (Canis familiaris) lived1-8. Here we analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today. This population connectivity allowed us to detect natural selection across the time series, including rapid fixation of mutations in the gene IFT88 40,000-30,000 years ago. We show that dogs are overall more closely related to ancient wolves from eastern Eurasia than to those from western Eurasia, suggesting a domestication process in the east. However, we also found that dogs in the Near East and Africa derive up to half of their ancestry from a distinct population related to modern southwest Eurasian wolves, reflecting either an independent domestication process or admixture from local wolves. None of the analysed ancient wolf genomes is a direct match for either of these dog ancestries, meaning that the exact progenitor populations remain to be located.


Assuntos
Cães , Genoma , Genômica , Filogenia , Lobos , África , Animais , DNA Antigo/análise , Cães/genética , Domesticação , Europa (Continente) , Genoma/genética , História Antiga , Oriente Médio , Mutação , América do Norte , Seleção Genética , Sibéria , Proteínas Supressoras de Tumor/genética , Lobos/classificação , Lobos/genética
2.
PLoS One ; 16(9): e0257041, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34492092

RESUMO

The branched reduction system at the Heidenschmiede described here is hitherto exceptional for the Middle Paleolithic of the Swabian Jura. By means of refits and supporting objects, we are able to describe a superordinate reduction system that combines several individual reduction concepts, such as Levallois and blade production, within one volume. In the Middle Paleolithic of the Swabian Jura, blade technology has thus far played a rather minor role. On the one hand, it is possible to split a selected volume (nodule) into three parts, which are reduced separately according to individual concepts. On the other hand, it is also possible to reduce parts of a volume with one concept first and then with another. The hypothetical reduction system can be branched or linear, thus emphasizing the technological flexibility in core reduction, which requires a high degree of cognitive skills of three-dimensional imagination.


Assuntos
Adaptação Fisiológica , Arqueologia , Homem de Neandertal/fisiologia , Animais , Fósseis , Imageamento Tridimensional , Datação Radiométrica
3.
Sci Rep ; 11(1): 5137, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664287

RESUMO

Dogs are known to be the oldest animals domesticated by humans. Although many studies have examined wolf domestication, the geographic and temporal origin of this process is still being debated. To address this issue, our study sheds new light on the early stages of wolf domestication during the Magdalenian period (16-14 ka cal BP) in the Hegau Jura region (Southwestern Germany and Switzerland). By combining morphology, genetics, and isotopes, our multidisciplinary approach helps to evaluate alternate processes driving the early phases of domestication. The isotope analysis uncovered a restricted, low δ15N protein diet for all analyzed Gnirshöhle specimens, while morphological examinations and phylogenetic relationships did not unequivocally assign them to one or the other canid lineage. Intriguingly, the newly generated mitochondrial canid genomes span the entire genetic diversity of modern dogs and wolves. Such high mitochondrial diversity could imply that Magdalenian people tamed and reared animals originating from different wolf lineages. We discuss our results in light of three ecological hypotheses and conclude that both domestication and the existence of a specialized wolf ecomorph are highly probable. However, due to their proximity to humans and a restricted diet, we propose domestication as the most likely scenario explaining the patterns observed herein.


Assuntos
Canidae/genética , DNA Mitocondrial/genética , Filogenia , Lobos/genética , Animais , Cavernas , Cães , Domesticação , Fósseis , Suíça
4.
Sci Rep ; 9(1): 10700, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31417104

RESUMO

The cave bear (Ursus spelaeus) is one of the Late Pleistocene megafauna species that faced extinction at the end of the last ice age. Although it is represented by one of the largest fossil records in Europe and has been subject to several interdisciplinary studies including palaeogenetic research, its fate remains highly controversial. Here, we used a combination of hybridisation capture and next generation sequencing to reconstruct 59 new complete cave bear mitochondrial genomes (mtDNA) from 14 sites in Western, Central and Eastern Europe. In a Bayesian phylogenetic analysis, we compared them to 64 published cave bear mtDNA sequences to reconstruct the population dynamics and phylogeography during the Late Pleistocene. We found five major mitochondrial DNA lineages resulting in a noticeably more complex biogeography of the European lineages during the last 50,000 years than previously assumed. Furthermore, our calculated effective female population sizes suggest a drastic cave bear population decline starting around 40,000 years ago at the onset of the Aurignacian, coinciding with the spread of anatomically modern humans in Europe. Thus, our study supports a potential significant human role in the general extinction and local extirpation of the European cave bear and illuminates the fate of this megafauna species.


Assuntos
Genoma Mitocondrial , Ursidae/genética , Animais , Teorema de Bayes , DNA Mitocondrial , Europa (Continente) , Extinção Biológica , Feminino , Fósseis , Filogenia , Filogeografia , Densidade Demográfica , Análise de Sequência de DNA
5.
Mol Ecol Resour ; 18(6): 1196-1208, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29877032

RESUMO

The prevalence of contaminant microbial DNA in ancient bone samples represents the principal limiting factor for palaeogenomic studies, as it may comprise more than 99% of DNA molecules obtained. Efforts to exclude or reduce this contaminant fraction have been numerous but also variable in their success. Here, we present a simple but highly effective method to increase the relative proportion of endogenous molecules obtained from ancient bones. Using computed tomography (CT) scanning, we identify the densest region of a bone as optimal for sampling. This approach accurately identifies the densest internal regions of petrous bones, which are known to be a source of high-purity ancient DNA. For ancient long bones, CT scans reveal a high-density outermost layer, which has been routinely removed and discarded prior to DNA extraction. For almost all long bones investigated, we find that targeted sampling of this outermost layer provides an increase in endogenous DNA content over that obtained from softer, trabecular bone. This targeted sampling can produce as much as 50-fold increase in the proportion of endogenous DNA, providing a directly proportional reduction in sequencing costs for shotgun sequencing experiments. The observed increases in endogenous DNA proportion are not associated with any reduction in absolute endogenous molecule recovery. Although sampling the outermost layer can result in higher levels of human contamination, some bones were found to have more contamination associated with the internal bone structures. Our method is highly consistent, reproducible and applicable across a wide range of bone types, ages and species. We predict that this discovery will greatly extend the potential to study ancient populations and species in the genomics era.


Assuntos
Osso e Ossos/química , DNA Antigo/análise , DNA Antigo/isolamento & purificação , Fósseis , Tomografia Computadorizada por Raios X/métodos , Humanos
6.
Sci Rep ; 7(1): 17714, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29255197

RESUMO

The population dynamics of the Pleistocene woolly mammoth (Mammuthus primigenius) has been the subject of intensive palaeogenetic research. Although a large number of mitochondrial genomes across Eurasia have been reconstructed, the available data remains geographically sparse and mostly focused on eastern Eurasia. Thus, population dynamics in other regions have not been extensively investigated. Here, we use a multi-method approach utilising proteomic, stable isotope and genetic techniques to identify and generate twenty woolly mammoth mitochondrial genomes, and associated dietary stable isotopic data, from highly fragmentary Late Pleistocene material from central Europe. We begin to address region-specific questions regarding central European woolly mammoth populations, highlighting parallels with a previous replacement event in eastern Eurasia ten thousand years earlier. A high number of shared derived mutations between woolly mammoth mitochondrial clades are identified, questioning previous phylogenetic analysis and thus emphasizing the need for nuclear DNA studies to explicate the increasingly complex genetic history of the woolly mammoth.


Assuntos
DNA Mitocondrial/genética , Mamutes/genética , Animais , DNA Antigo/análise , Europa (Continente) , Extinção Biológica , Fósseis , Genoma Mitocondrial/genética , Haplótipos/genética , Filogenia , Dinâmica Populacional , Proteômica/métodos , Análise de Sequência de DNA
7.
Sci Rep ; 6: 32969, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27615365

RESUMO

Sub-fossilised remains may still contain highly degraded ancient DNA (aDNA) useful for palaeogenetic investigations. Whether X-ray computed [micro-] tomography ([µ]CT) imaging of these fossils may further damage aDNA remains debated. Although the effect of X-ray on DNA in living organisms is well documented, its impact on aDNA molecules is unexplored. Here we investigate the effects of synchrotron X-ray irradiation on aDNA from Pleistocene bones. A clear correlation appears between decreasing aDNA quantities and accumulating X-ray dose-levels above 2000 Gray (Gy). We further find that strong X-ray irradiation reduces the amount of nucleotide misincorporations at the aDNA molecule ends. No representative effect can be detected for doses below 200 Gy. Dosimetry shows that conventional µCT usually does not reach the risky dose level, while classical synchrotron imaging can degrade aDNA significantly. Optimised synchrotron protocols and simple rules introduced here are sufficient to ensure that fossils can be scanned without impairing future aDNA studies.


Assuntos
Osso e Ossos/diagnóstico por imagem , DNA Antigo , Fósseis/diagnóstico por imagem , Animais , Relação Dose-Resposta à Radiação , Síncrotrons , Raios X
8.
Sci Rep ; 5: 10853, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-26052672

RESUMO

The giant deer Megaloceros giganteus is among the most fascinating Late Pleistocene Eurasian megafauna that became extinct at the end of the last ice age. Important questions persist regarding its phylogenetic relationship to contemporary taxa and the reasons for its extinction. We analyzed two large ancient cervid bone fragments recovered from cave sites in the Swabian Jura (Baden-Württemberg, Germany) dated to 12,000 years ago. Using hybridization capture in combination with next generation sequencing, we were able to reconstruct nearly complete mitochondrial genomes from both specimens. Both mtDNAs cluster phylogenetically with fallow deer and show high similarity to previously studied partial Megaloceros giganteus DNA from Kamyshlov in western Siberia and Killavullen in Ireland. The unexpected presence of Megaloceros giganteus in Southern Germany after the Ice Age suggests a later survival in Central Europe than previously proposed. The complete mtDNAs provide strong phylogenetic support for a Dama-Megaloceros clade. Furthermore, isotope analyses support an increasing competition between giant deer, red deer, and reindeer after the Last Glacial Maximum, which might have contributed to the extinction of Megaloceros in Central Europe.


Assuntos
DNA Mitocondrial/genética , Cervos/genética , Genoma Mitocondrial/genética , Animais , Europa (Continente) , Fósseis , Alemanha , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Filogenia , Análise de Sequência de DNA/métodos
9.
Mol Biol Evol ; 27(5): 975-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20335279

RESUMO

The causes of the late Pleistocene megafaunal extinctions are still enigmatic. Although the fossil record can provide approximations for when a species went extinct, the timing of its disappearance alone cannot resolve the causes and mode of the decline preceding its extinction. However, ancient DNA analyses can reveal population size changes over time and narrow down potential causes of extinction. Here, we present an ancient DNA study comparing late Pleistocene population dynamics of two closely related species, cave and brown bears. We found that the decline of cave bears started approximately 25,000 years before their extinction, whereas brown bear population size remained constant. We conclude that neither the effects of climate change nor human hunting alone can be responsible for the decline of the cave bear and suggest that a complex of factors including human competition for cave sites lead to the cave bear's extinction.


Assuntos
Extinção Biológica , Ursidae/genética , Ursidae/fisiologia , Animais , Comportamento Competitivo , Ecossistema , Feminino , História Antiga , Humanos , Densidade Demográfica , Ursidae/classificação
10.
Nature ; 460(7256): 737-40, 2009 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-19553935

RESUMO

Considerable debate surrounds claims for early evidence of music in the archaeological record. Researchers universally accept the existence of complex musical instruments as an indication of fully modern behaviour and advanced symbolic communication but, owing to the scarcity of finds, the archaeological record of the evolution and spread of music remains incomplete. Although arguments have been made for Neanderthal musical traditions and the presence of musical instruments in Middle Palaeolithic assemblages, concrete evidence to support these claims is lacking. Here we report the discovery of bone and ivory flutes from the early Aurignacian period of southwestern Germany. These finds demonstrate the presence of a well-established musical tradition at the time when modern humans colonized Europe, more than 35,000 calendar years ago. Other than the caves of the Swabian Jura, the earliest secure archaeological evidence for music comes from sites in France and Austria and post-date 30,000 years ago.


Assuntos
Música/história , Animais , Aves/anatomia & histologia , Osso e Ossos , Cultura , Alemanha , História Antiga , Cornos
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