TY - GEN A1 - Xenikoudakis, Georgios A1 - Ahmed, Mayeesha A1 - Harris, Jacob Colt A1 - Wadleigh, Rachel A1 - Paijmans, Johanna L. A. A1 - Hartmann, Stefanie A1 - Barlow, Axel A1 - Lerner, Heather A1 - Hofreiter, Michael T1 - Ancient DNA reveals twenty million years of aquatic life in beavers T2 - Current biology : CB N2 - Xenikoudakis et al. report a partial mitochondrial genome of the extinct giant beaver Castoroides and estimate the origin of aquatic behavior in beavers to approximately 20 million years. This time estimate coincides with the extinction of terrestrial beavers and raises the question whether the two events had a common cause. Y1 - 2020 U6 - https://doi.org/10.1016/j.cub.2019.12.041 SN - 0960-9822 SN - 1879-0445 VL - 30 IS - 3 SP - R110 EP - R111 PB - Current Biology Ltd. CY - London ER - TY - GEN A1 - Zancolli, Giulia A1 - Baker, Timothy G. A1 - Barlow, Axel A1 - Bradley, Rebecca K. A1 - Calvete, Juan J. A1 - Carter, Kimberley C. A1 - de Jager, Kaylah A1 - Owens, John Benjamin A1 - Price, Jenny Forrester A1 - Sanz, Libia A1 - Scholes-Higham, Amy A1 - Shier, Liam A1 - Wood, Liam A1 - Wüster, Catharine E. A1 - Wüster, Wolfgang T1 - Is hybridization a source of adaptive venom variation in rattlesnakes? BT - a test, using a crotalus scutulatus × viridis hybrid zone in southwestern New Mexico T2 - Toxins N2 - Venomous snakes often display extensive variation in venom composition both between and within species. However, the mechanisms underlying the distribution of different toxins and venom types among populations and taxa remain insufficiently known. Rattlesnakes (Crotalus, Sistrurus) display extreme inter-and intraspecific variation in venom composition, centered particularly on the presence or absence of presynaptically neurotoxic phospholipases A2 such as Mojave toxin (MTX). Interspecific hybridization has been invoked as a mechanism to explain the distribution of these toxins across rattlesnakes, with the implicit assumption that they are adaptively advantageous. Here, we test the potential of adaptive hybridization as a mechanism for venom evolution by assessing the distribution of genes encoding the acidic and basic subunits of Mojave toxin across a hybrid zone between MTX-positive Crotalus scutulatus and MTX-negative C. viridis in southwestern New Mexico, USA. Analyses of morphology, mitochondrial and single copy-nuclear genes document extensive admixture within a narrow hybrid zone. The genes encoding the two MTX subunits are strictly linked, and found in most hybrids and backcrossed individuals, but not in C. viridis away from the hybrid zone. Presence of the genes is invariably associated with presence of the corresponding toxin in the venom. We conclude that introgression of highly lethal neurotoxins through hybridization is not necessarily favored by natural selection in rattlesnakes, and that even extensive hybridization may not lead to introgression of these genes into another species. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 443 KW - adaptation KW - Crotalus KW - evolution KW - hybridization KW - introgression KW - Mojave toxin KW - molecular evolution KW - venom Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-407595 ER - TY - GEN A1 - Paijmans, Johanna L. A. A1 - Barlow, Axel A1 - Förster, Daniel W. A1 - Henneberger, Kirstin A1 - Meyer, Matthias A1 - Nickel, Birgit A1 - Nagel, Doris A1 - Worsøe Havmøller, Rasmus A1 - Baryshnikov, Gennady F. A1 - Joger, Ulrich A1 - Rosendahl, Wilfried A1 - Hofreiter, Michael T1 - Historical biogeography of the leopard (Panthera pardus) and its extinct Eurasian populations T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Background Resolving the historical biogeography of the leopard (Panthera pardus) is a complex issue, because patterns inferred from fossils and from molecular data lack congruence. Fossil evidence supports an African origin, and suggests that leopards were already present in Eurasia during the Early Pleistocene. Analysis of DNA sequences however, suggests a more recent, Middle Pleistocene shared ancestry of Asian and African leopards. These contrasting patterns led researchers to propose a two-stage hypothesis of leopard dispersal out of Africa: an initial Early Pleistocene colonisation of Asia and a subsequent replacement by a second colonisation wave during the Middle Pleistocene. The status of Late Pleistocene European leopards within this scenario is unclear: were these populations remnants of the first dispersal, or do the last surviving European leopards share more recent ancestry with their African counterparts? Results In this study, we generate and analyse mitogenome sequences from historical samples that span the entire modern leopard distribution, as well as from Late Pleistocene remains. We find a deep bifurcation between African and Eurasian mitochondrial lineages (~ 710 Ka), with the European ancient samples as sister to all Asian lineages (~ 483 Ka). The modern and historical mainland Asian lineages share a relatively recent common ancestor (~ 122 Ka), and we find one Javan sample nested within these. Conclusions The phylogenetic placement of the ancient European leopard as sister group to Asian leopards suggests that these populations originate from the same out-of-Africa dispersal which founded the Asian lineages. The coalescence time found for the mitochondrial lineages aligns well with the earliest undisputed fossils in Eurasia, and thus encourages a re-evaluation of the identification of the much older putative leopard fossils from the region. The relatively recent ancestry of all mainland Asian leopard lineages suggests that these populations underwent a severe population bottleneck during the Pleistocene. Finally, although only based on a single sample, the unexpected phylogenetic placement of the Javan leopard could be interpreted as evidence for exchange of mitochondrial lineages between Java and mainland Asia, calling for further investigation into the evolutionary history of this subspecies. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 505 KW - Ancient DNA KW - Hybridisation capture KW - Leopards KW - Mitochondrial genomes KW - Mitogenomes KW - mtDNA KW - Palaeogenetics KW - Panthera pardus Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-422555 SN - 1866-8372 IS - 505 ER - TY - GEN A1 - Hofreiter, Michael A1 - Paijmans, Johanna L. A. A1 - Goodchild, Helen A1 - Speller, Camilla F. A1 - Barlow, Axel A1 - Gonzalez-Fortes, Gloria M. A1 - Thomas, Jessica A. A1 - Ludwig, Arne A1 - Collins, Matthew J. T1 - The future of ancient DNA BT - technical advances and conceptual shifts T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - Technological innovations such as next generation sequencing and DNA hybridisation enrichment have resulted in multi-fold increases in both the quantity of ancient DNA sequence data and the time depth for DNA retrieval. To date, over 30 ancient genomes have been sequenced, moving from 0.7x coverage (mammoth) in 2008 to more than 50x coverage (Neanderthal) in 2014. Studies of rapid evolutionary changes, such as the evolution and spread of pathogens and the genetic responses of hosts, or the genetics of domestication and climatic adaptation, are developing swiftly and the importance of palaeogenomics for investigating evolutionary processes during the last million years is likely to increase considerably. However, these new datasets require new methods of data processing and analysis, as well as conceptual changes in interpreting the results. In this review we highlight important areas of future technical and conceptual progress and discuss research topics in the rapidly growing field of palaeogenomics. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 908 KW - ancient DNA KW - hybridisation capture KW - multi-locus data KW - next generation sequencing (NGS) KW - palaeogenomics KW - population genomics Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-438816 SN - 1866-8372 IS - 908 SP - 284 EP - 295 ER - TY - GEN A1 - Westbury, Michael V. A1 - Baleka, Sina Isabelle A1 - Barlow, Axel A1 - Hartmann, Stefanie A1 - Paijmans, Johanna L. A. A1 - Kramarz, Alejandro A1 - Forasiepi, Analía M. A1 - Bond, Mariano A1 - Gelfo, Javier N. A1 - Reguero, Marcelo A. A1 - López-Mendoza, Patricio A1 - Taglioretti, Matias A1 - Scaglia, Fernando A1 - Rinderknecht, Andrés A1 - Jones, Washington A1 - Mena, Francisco A1 - Billet, Guillaume A1 - de Muizon, Christian A1 - Aguilar, José Luis A1 - MacPhee, Ross D.E. A1 - Hofreiter, Michael T1 - A mitogenomic timetree for Darwin's enigmatic South American mammal Macrauchenia patachonica T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - The unusual mix of morphological traits displayed by extinct South American native ungulates (SANUs) confounded both Charles Darwin, who first discovered them, and Richard Owen, who tried to resolve their relationships. Here we report an almost complete mitochondrial genome for the litoptern Macrauchenia. Our dated phylogenetic tree places Macrauchenia as sister to Perissodactyla, but close to the radiation of major lineages within Laurasiatheria. This position is consistent with a divergence estimate of B66Ma (95% credibility interval, 56.64-77.83 Ma) obtained for the split between Macrauchenia and other Panperissodactyla. Combined with their morphological distinctiveness, this evidence supports the positioning of Litopterna (possibly in company with other SANU groups) as a separate order within Laurasiatheria. We also show that, when using strict criteria, extinct taxa marked by deep divergence times and a lack of close living relatives may still be amenable to palaeogenomic analysis through iterative mapping against more distant relatives. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 793 KW - ancient DNA KW - evolutionary history KW - genome sequence KW - reveals KW - contamination KW - alignment KW - reads KW - bones Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-440801 SN - 1866-8372 IS - 793 ER - TY - GEN A1 - Taron, Ulrike H. A1 - Lell, Moritz A1 - Barlow, Axel A1 - Paijmans, Johanna L. A. T1 - Testing of Alignment Parameters for Ancient Samples BT - Evaluating and Optimizing Mapping Parameters for Ancient Samples Using the TAPAS Tool T2 - Genes N2 - High-throughput sequence data retrieved from ancient or other degraded samples has led to unprecedented insights into the evolutionary history of many species, but the analysis of such sequences also poses specific computational challenges. The most commonly used approach involves mapping sequence reads to a reference genome. However, this process becomes increasingly challenging with an elevated genetic distance between target and reference or with the presence of contaminant sequences with high sequence similarity to the target species. The evaluation and testing of mapping efficiency and stringency are thus paramount for the reliable identification and analysis of ancient sequences. In this paper, we present ‘TAPAS’, (Testing of Alignment Parameters for Ancient Samples), a computational tool that enables the systematic testing of mapping tools for ancient data by simulating sequence data reflecting the properties of an ancient dataset and performing test runs using the mapping software and parameter settings of interest. We showcase TAPAS by using it to assess and improve mapping strategy for a degraded sample from a banded linsang (Prionodon linsang), for which no closely related reference is currently available. This enables a 1.8-fold increase of the number of mapped reads without sacrificing mapping specificity. The increase of mapped reads effectively reduces the need for additional sequencing, thus making more economical use of time, resources, and sample material. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 415 KW - ancient DNA KW - short-read mapping KW - palaeogenomics KW - alignment sensitivity / specificity Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-409683 ER - TY - GEN A1 - Basler, Nikolas A1 - Xenikoudakis, Georgios A1 - Westbury, Michael V. A1 - Song, Lingfeng A1 - Sheng, Guilian A1 - Barlow, Axel T1 - Reduction of the contaminant fraction of DNA obtained from an ancient giant panda bone T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Objective: A key challenge in ancient DNA research is massive microbial DNA contamination from the deposition site which accumulates post mortem in the study organism’s remains. Two simple and cost-effective methods to enrich the relative endogenous fraction of DNA in ancient samples involve treatment of sample powder with either bleach or Proteinase K pre-digestion prior to DNA extraction. Both approaches have yielded promising but vary-ing results in other studies. Here, we contribute data on the performance of these methods using a comprehensive and systematic series of experiments applied to a single ancient bone fragment from a giant panda (Ailuropoda melanoleuca).Results: Bleach and pre-digestion treatments increased the endogenous DNA content up to ninefold. However, the absolute amount of DNA retrieved was dramatically reduced by all treatments. We also observed reduced DNA damage patterns in pre-treated libraries compared to untreated ones, resulting in longer mean fragment lengths and reduced thymine over-representation at fragment ends. Guanine–cytosine (GC) contents of both mapped and total reads are consistent between treatments and conform to general expectations, indicating no obvious biasing effect of the applied methods. Our results therefore confirm the value of bleach and pre-digestion as tools in palaeog-enomic studies, providing sufficient material is available. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 715 KW - ancient DNA (aDNA) KW - bleach KW - pre-digestion KW - endogenous content KW - palaeogenomics KW - paleogenomics KW - next generation sequencing (NGS) KW - giant panda KW - Ailuropoda melanoleuca Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-428151 SN - 1866-8372 IS - 715 ER - TY - JOUR A1 - Paijmans, Johanna L. A. A1 - Barlow, Axel A1 - Förster, Daniel W. A1 - Henneberger, Kirstin A1 - Meyer, Matthias A1 - Nickel, Birgit A1 - Nagel, Doris A1 - Worsøe Havmøller, Rasmus A1 - Baryshnikov, Gennady F. A1 - Joger, Ulrich A1 - Rosendahl, Wilfried A1 - Hofreiter, Michael T1 - Historical biogeography of the leopard (Panthera pardus) and its extinct Eurasian populations JF - BMC Evolutionary Biology N2 - Background Resolving the historical biogeography of the leopard (Panthera pardus) is a complex issue, because patterns inferred from fossils and from molecular data lack congruence. Fossil evidence supports an African origin, and suggests that leopards were already present in Eurasia during the Early Pleistocene. Analysis of DNA sequences however, suggests a more recent, Middle Pleistocene shared ancestry of Asian and African leopards. These contrasting patterns led researchers to propose a two-stage hypothesis of leopard dispersal out of Africa: an initial Early Pleistocene colonisation of Asia and a subsequent replacement by a second colonisation wave during the Middle Pleistocene. The status of Late Pleistocene European leopards within this scenario is unclear: were these populations remnants of the first dispersal, or do the last surviving European leopards share more recent ancestry with their African counterparts? Results In this study, we generate and analyse mitogenome sequences from historical samples that span the entire modern leopard distribution, as well as from Late Pleistocene remains. We find a deep bifurcation between African and Eurasian mitochondrial lineages (~ 710 Ka), with the European ancient samples as sister to all Asian lineages (~ 483 Ka). The modern and historical mainland Asian lineages share a relatively recent common ancestor (~ 122 Ka), and we find one Javan sample nested within these. Conclusions The phylogenetic placement of the ancient European leopard as sister group to Asian leopards suggests that these populations originate from the same out-of-Africa dispersal which founded the Asian lineages. The coalescence time found for the mitochondrial lineages aligns well with the earliest undisputed fossils in Eurasia, and thus encourages a re-evaluation of the identification of the much older putative leopard fossils from the region. The relatively recent ancestry of all mainland Asian leopard lineages suggests that these populations underwent a severe population bottleneck during the Pleistocene. Finally, although only based on a single sample, the unexpected phylogenetic placement of the Javan leopard could be interpreted as evidence for exchange of mitochondrial lineages between Java and mainland Asia, calling for further investigation into the evolutionary history of this subspecies. KW - Ancient DNA KW - Hybridisation capture KW - Leopards KW - Mitochondrial genomes KW - Mitogenomes KW - mtDNA KW - Palaeogenetics KW - Panthera pardus Y1 - 2018 U6 - https://doi.org/10.1186/s12862-018-1268-0 SN - 1471-2148 VL - 18 IS - 156 PB - BioMed Central und Springer CY - London, Berlin und Heidelberg ER - TY - JOUR A1 - Taron, Ulrike H. A1 - Lell, Moritz A1 - Barlow, Axel A1 - Paijmans, Johanna L. A. T1 - Testing of Alignment Parameters for Ancient Samples BT - Evaluating and Optimizing Mapping Parameters for Ancient Samples Using the TAPAS Tool JF - Genes N2 - High-throughput sequence data retrieved from ancient or other degraded samples has led to unprecedented insights into the evolutionary history of many species, but the analysis of such sequences also poses specific computational challenges. The most commonly used approach involves mapping sequence reads to a reference genome. However, this process becomes increasingly challenging with an elevated genetic distance between target and reference or with the presence of contaminant sequences with high sequence similarity to the target species. The evaluation and testing of mapping efficiency and stringency are thus paramount for the reliable identification and analysis of ancient sequences. In this paper, we present ‘TAPAS’, (Testing of Alignment Parameters for Ancient Samples), a computational tool that enables the systematic testing of mapping tools for ancient data by simulating sequence data reflecting the properties of an ancient dataset and performing test runs using the mapping software and parameter settings of interest. We showcase TAPAS by using it to assess and improve mapping strategy for a degraded sample from a banded linsang (Prionodon linsang), for which no closely related reference is currently available. This enables a 1.8-fold increase of the number of mapped reads without sacrificing mapping specificity. The increase of mapped reads effectively reduces the need for additional sequencing, thus making more economical use of time, resources, and sample material. KW - ancient DNA KW - short-read mapping KW - palaeogenomics KW - alignment sensitivity / specificity Y1 - 2018 U6 - https://doi.org/10.3390/genes9030157 SN - 2073-4425 VL - 9 IS - 3 SP - 1 EP - 12 PB - Molecular Diversity Preservation International CY - Basel ER - TY - GEN A1 - Barlow, Axel A1 - Hartmann, Stefanie A1 - Gonzalez, Javier A1 - Hofreiter, Michael A1 - Paijmans, Johanna L. A. T1 - Consensify BT - a method for generating pseudohaploid genome sequences from palaeogenomic datasets with reduced error rates T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - A standard practise in palaeogenome analysis is the conversion of mapped short read data into pseudohaploid sequences, frequently by selecting a single high-quality nucleotide at random from the stack of mapped reads. This controls for biases due to differential sequencing coverage, but it does not control for differential rates and types of sequencing error, which are frequently large and variable in datasets obtained from ancient samples. These errors have the potential to distort phylogenetic and population clustering analyses, and to mislead tests of admixture using D statistics. We introduce Consensify, a method for generating pseudohaploid sequences, which controls for biases resulting from differential sequencing coverage while greatly reducing error rates. The error correction is derived directly from the data itself, without the requirement for additional genomic resources or simplifying assumptions such as contemporaneous sampling. For phylogenetic and population clustering analysis, we find that Consensify is less affected by artefacts than methods based on single read sampling. For D statistics, Consensify is more resistant to false positives and appears to be less affected by biases resulting from different laboratory protocols than other frequently used methods. Although Consensify is developed with palaeogenomic data in mind, it is applicable for any low to medium coverage short read datasets. We predict that Consensify will be a useful tool for future studies of palaeogenomes. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1033 KW - palaeogenomics KW - ancient DNA KW - sequencing error KW - error reduction KW - D statistics KW - bioinformatics Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-472521 SN - 1866-8372 IS - 1033 ER -