146 results on '"Axel Janke"'
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2. High-speed whole-genome sequencing of a Whippet: Rapid chromosome-level assembly and annotation of an extremely fast dog’s genome
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Marcel Nebenführ, David Prochotta, Alexander Ben Hamadou, Axel Janke, Charlotte Gerheim, Christian Betz, Carola Greve, and Hanno Jörn Bolz
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Electronic computers. Computer science ,QA75.5-76.95 - Abstract
The time required for genome sequencing and de novo assembly depends on the interaction between laboratory work, sequencing capacity, and the bioinformatics workflow, often constrained by external sequencing services. Bringing together academic biodiversity institutes and a medical diagnostics company with extensive sequencing capabilities, we aimed at generating a high-quality mammalian de novo genome in minimal time. We present the first chromosome-level genome assembly of the Whippet, using PacBio long-read high-fidelity sequencing and reference-guided scaffolding. The final assembly has a contig N50 of 55 Mbp and a scaffold N50 of 65.7 Mbp. The total assembly length is 2.47 Gbp, of which 2.43 Gpb were scaffolded into 39 chromosome-length scaffolds. Annotation using mammalian genomes and transcriptome data yielded 28,383 transcripts, 90.9% complete BUSCO genes, and identified 36.5% repeat content. Sequencing, assembling, and scaffolding the chromosome-level genome of the Whippet took less than a week, adding another high-quality reference genome to the available sequences of domestic dog breeds.
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- 2024
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3. Genomic analysis reveals limited hybridization among three giraffe species in Kenya
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Raphael T. F. Coimbra, Sven Winter, Arthur Muneza, Stephanie Fennessy, Moses Otiende, Domnic Mijele, Symon Masiaine, Jenna Stacy-Dawes, Julian Fennessy, and Axel Janke
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East Africa ,Gene flow ,Giraffa ,Hybridization ,Introgression ,Population genomics ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background In the speciation continuum, the strength of reproductive isolation varies, and species boundaries are blurred by gene flow. Interbreeding among giraffe (Giraffa spp.) in captivity is known, and anecdotal reports of natural hybrids exist. In Kenya, Nubian (G. camelopardalis camelopardalis), reticulated (G. reticulata), and Masai giraffe sensu stricto (G. tippelskirchi tippelskirchi) are parapatric, and thus, the country might be a melting pot for these taxa. We analyzed 128 genomes of wild giraffe, 113 newly sequenced, representing these three taxa. Results We found varying levels of Nubian ancestry in 13 reticulated giraffe sampled across the Laikipia Plateau most likely reflecting historical gene flow between these two lineages. Although comparatively weaker signs of ancestral gene flow and potential mitochondrial introgression from reticulated into Masai giraffe were also detected, estimated admixture levels between these two lineages are minimal. Importantly, contemporary gene flow between East African giraffe lineages was not statistically significant. Effective population sizes have declined since the Late Pleistocene, more severely for Nubian and reticulated giraffe. Conclusions Despite historically hybridizing, these three giraffe lineages have maintained their overall genomic integrity suggesting effective reproductive isolation, consistent with the previous classification of giraffe into four species.
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- 2023
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4. Near chromosome-level and highly repetitive genome assembly of the snake pipefish Entelurus aequoreus (Syngnathiformes: Syngnathidae)
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Magnus Wolf, Bruno Lopes da Silva Ferrette, Raphael T. F. Coimbra, Menno de Jong, Marcel Nebenführ, David Prochotta, Yannis Schöneberg, Konstantin Zapf, Jessica Rosenbaum, Hannah A. Mc Intyre, Julia Maier, Clara C. S. de Souza, Lucas M. Gehlhaar, Melina J. Werner, Henrik Oechler, Marie Wittekind, Moritz Sonnewald, Maria A. Nilsson, Axel Janke, and Sven Winter
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Electronic computers. Computer science ,QA75.5-76.95 - Abstract
The snake pipefish, Entelurus aequoreus (Linnaeus, 1758), is a northern Atlantic fish inhabiting open seagrass environments that recently expanded its distribution range. Here, we present a highly contiguous, near chromosome-scale genome of E. aequoreus. The final assembly spans 1.6 Gbp in 7,391 scaffolds, with a scaffold N50 of 62.3 Mbp and L50 of 12. The 28 largest scaffolds (>21 Mbp) span 89.7% of the assembly length. A BUSCO completeness score of 94.1% and a mapping rate above 98% suggest a high assembly completeness. Repetitive elements cover 74.93% of the genome, one of the highest proportions identified in vertebrates. Our demographic modeling identified a peak in population size during the last interglacial period, suggesting the species might benefit from warmer water conditions. Our updated snake pipefish assembly is essential for future analyses of the morphological and molecular changes unique to the Syngnathidae.
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- 2024
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5. The genome of the pygmy right whale illuminates the evolution of rorquals
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Magnus Wolf, Konstantin Zapf, Deepak Kumar Gupta, Michael Hiller, Úlfur Árnason, and Axel Janke
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Pygmy right whale ,Caperea marginata ,Whole-genome sequencing ,Phylogenomics ,Rorquals ,Positive selection ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background Baleen whales are a clade of gigantic and highly specialized marine mammals. Their genomes have been used to investigate their complex evolutionary history and to decipher the molecular mechanisms that allowed them to reach these dimensions. However, many unanswered questions remain, especially about the early radiation of rorquals and how cancer resistance interplays with their huge number of cells. The pygmy right whale is the smallest and most elusive among the baleen whales. It reaches only a fraction of the body length compared to its relatives and it is the only living member of an otherwise extinct family. This placement makes the pygmy right whale genome an interesting target to update the complex phylogenetic past of baleen whales, because it splits up an otherwise long branch that leads to the radiation of rorquals. Apart from that, genomic data of this species might help to investigate cancer resistance in large whales, since these mechanisms are not as important for the pygmy right whale as in other giant rorquals and right whales. Results Here, we present a first de novo genome of the species and test its potential in phylogenomics and cancer research. To do so, we constructed a multi-species coalescent tree from fragments of a whole-genome alignment and quantified the amount of introgression in the early evolution of rorquals. Furthermore, a genome-wide comparison of selection rates between large and small-bodied baleen whales revealed a small set of conserved candidate genes with potential connections to cancer resistance. Conclusions Our results suggest that the evolution of rorquals is best described as a hard polytomy with a rapid radiation and high levels of introgression. The lack of shared positive selected genes between different large-bodied whale species supports a previously proposed convergent evolution of gigantism and hence cancer resistance in baleen whales.
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- 2023
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6. Range-wide whole-genome resequencing of the brown bear reveals drivers of intraspecies divergence
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Menno J. de Jong, Aidin Niamir, Magnus Wolf, Andrew C. Kitchener, Nicolas Lecomte, Ivan V. Seryodkin, Steven R. Fain, Snorre B. Hagen, Urmas Saarma, and Axel Janke
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Biology (General) ,QH301-705.5 - Abstract
The genetic structure of modern-day brown bears mainly reflects contemporary population connectivity. Recent gene flow barriers have obscured the genomic signatures of postglacial recolonisation.
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- 2023
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7. Speciation and population divergence in a mutualistic seed dispersing bird
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Jordi de Raad, Martin Päckert, Martin Irestedt, Axel Janke, Alexey P. Kryukov, Jochen Martens, Yaroslav A. Red’kin, Yuehua Sun, Till Töpfer, Matthias Schleuning, Eike Lena Neuschulz, and Maria A. Nilsson
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Biology (General) ,QH301-705.5 - Abstract
Genomic and phylogeographic analyses indicate that resource-specialization did not play a major role in the diversification and speciation of seed dispersing nutcrackers
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- 2022
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8. Informing conservation strategies with museum genomics: Long‐term effects of past anthropogenic persecution on the elusive European wildcat
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Alina von Thaden, Berardino Cocchiararo, Sarah Ashley Mueller, Tobias Erik Reiners, Katharina Reinert, Iris Tuchscherer, Axel Janke, and Carsten Nowak
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archival DNA ,bottleneck ,conservation genetics ,Felis silvestris ,museum genomics ,spatiotemporal data ,Ecology ,QH540-549.5 - Abstract
Abstract Like many carnivore species, European wildcats (Felis silvestris) have suffered severe anthropogenic population declines in the past, resulting in a strong population bottleneck at the beginning of the 20th century. In Germany, the species has managed to survive its near extinction in small isolated areas and is currently recolonizing former habitats owing to legal protection and concerted conservation efforts. Here, we SNP‐genotyped and mtDNA‐sequenced 56 historical and 650 contemporary samples to assess the impact of massive persecution on genetic diversity, population structure, and hybridization dynamics of wildcats. Spatiotemporal analyses suggest that the presumed postglacial differentiation between two genetically distinct metapopulations in Germany is in fact the result of the anthropogenic bottleneck followed by re‐expansion from few secluded refugia. We found that, despite the bottleneck, populations experienced no severe genetic erosion, nor suffered from elevated inbreeding or showed signs of increased hybridization with domestic cats. Our findings have significant implications for current wildcat conservation strategies, as the data analyses show that the two presently recognized wildcat population clusters should be treated as a single conservation unit. Although current populations appear under no imminent threat from genetic factors, fostering connectivity through the implementation of forest corridors will facilitate the preservation of genetic diversity and promote long‐term viability. The present study documents how museum collections can be used as essential resource for assessing long‐term anthropogenic effects on natural populations, for example, regarding population structure and the delineation of appropriate conservation units, potentially informing todays' species conservation.
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- 2021
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9. Northern olingo (Bassaricyon gabbi), zorilla (Ictonyx striatus), and honey badger (Mellivora capensis) mitochondrial genomes and a phylogeny of Musteloidea
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Sven Winter, Julian Fennessy, Axel Janke, and Maria A. Nilsson
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Musteloidea ,mitochondrial genome ,honey badger ,olingo ,zorilla ,Evolution ,QH359-425 ,Ecology ,QH540-549.5 - Published
- 2023
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10. A taxonomic revision of the genus Phrynoglossus in Indochina with the description of a new species and comments on the classification within Occidozyginae (Amphibia, Anura, Dicroglossidae)
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Gunther Köhler, Joseph Vargas, Ni Lar Than, Tilman Schell, Axel Janke, Steffen U. Pauls, and Panupong Thammachoti
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Zoology ,QL1-991 - Abstract
We revise the frogs of the genus Phrynoglossus from Indochina based on data of external morphology, bioacoustics and molecular genetics. The results of this integrative study provide evidence for the recognition of three distinct species, one of which we describe as new. Phrynoglossus martensii has a vast geographic distribution from central and southern Thailand across southern China to Vietnam, Laos, and Cambodia. Phrynoglossus myanhessei sp. nov. is distributed in central Myanmar whereas Phrynoglossus magnapustulosus is restricted to the Khorat Plateau, Thailand. These three species occur in allopatry and differ in their mating calls, external morphology, and in genetic distances of the 16S gene of 3.8–5.9%. Finally, we discuss and provide evolutionary evidence for the recognition of Phrynoglossus as a genus distinct from Occidozyga. Members of both genera form reciprocal monophyletic groups in our analyses of mtDNA data (16S) and are well differentiated from each other in morphology and ecology. Furthermore, they differ in the amplexus mode with Phrynoglossus having an inguinal amplexus whereas it is axillary in Occidozyga. We further provide a de novo draft genome of the holotype based on short-read sequencing technology to a coverage of 25-fold. This resource will permanently link the genetic characterization of the species to the name-bearing type specimen.
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- 2021
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11. Improving the Chromosome-Level Genome Assembly of the Siamese Fighting Fish (Betta splendens) in a University Master’s Course
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Stefan Prost, Malte Petersen, Martin Grethlein, Sarah Joy Hahn, Nina Kuschik-Maczollek, Martyna Ewa Olesiuk, Jan-Olaf Reschke, Tamara Elke Schmey, Caroline Zimmer, Deepak K. Gupta, Tilman Schell, Raphael Coimbra, Jordi De Raad, Fritjof Lammers, Sven Winter, and Axel Janke
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chromosome-level genome assembly ,betta splendens ,master’s course ,Genetics ,QH426-470 - Abstract
Ever decreasing costs along with advances in sequencing and library preparation technologies enable even small research groups to generate chromosome-level assemblies today. Here we report the generation of an improved chromosome-level assembly for the Siamese fighting fish (Betta splendens) that was carried out during a practical university master’s course. The Siamese fighting fish is a popular aquarium fish and an emerging model species for research on aggressive behavior. We updated the current genome assembly by generating a new long-read nanopore-based assembly with subsequent scaffolding to chromosome-level using previously published Hi-C data. The use of ∼35x nanopore-based long-read data sequenced on a MinION platform (Oxford Nanopore Technologies) allowed us to generate a baseline assembly of only 1,276 contigs with a contig N50 of 2.1 Mbp, and a total length of 441 Mbp. Scaffolding using the Hi-C data resulted in 109 scaffolds with a scaffold N50 of 20.7 Mbp. More than 99% of the assembly is comprised in 21 scaffolds. The assembly showed the presence of 96.1% complete BUSCO genes from the Actinopterygii dataset indicating a high quality of the assembly. We present an improved full chromosome-level assembly of the Siamese fighting fish generated during a university master’s course. The use of ∼35× long-read nanopore data drastically improved the baseline assembly in terms of continuity. We show that relatively in-expensive high-throughput sequencing technologies such as the long-read MinION sequencing platform can be used in educational settings allowing the students to gain practical skills in modern genomics and generate high quality results that benefit downstream research projects.
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- 2020
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12. De novo Genome Assembly of the Raccoon Dog (Nyctereutes procyonoides)
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Luis J. Chueca, Judith Kochmann, Tilman Schell, Carola Greve, Axel Janke, Markus Pfenninger, and Sven Klimpel
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genome assembly and annotation ,SARS-CoV-2 ,Carnivora ,raccoon dog (Nyctereutes procyonoides) ,B chromosome ,Genetics ,QH426-470 - Published
- 2021
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13. Chromosome-level genome assembly of a benthic associated Syngnathiformes species: the common dragonet, Callionymus lyra
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Sven Winter, Stefan Prost, Jordi de Raad, Raphael T. F. Coimbra, Magnus Wolf, Marcel Nebenführ, Annika Held, Melina Kurzawe, Ramona Papapostolou, Jade Tessien, Julian Bludau, Andreas Kelch, Sarah Gronefeld, Yannis Schöneberg, Christian Zeitz, Konstantin Zapf, David Prochotta, Maximilian Murphy, Monica M. Sheffer, Moritz Sonnewald, Maria A. Nilsson, and Axel Janke
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Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Background The common dragonet, Callionymus lyra, is one of three Callionymus species inhabiting the North Sea. All three species show strong sexual dimorphism. The males show strong morphological differentiation, e.g., species-specific colouration and size relations, while the females of different species have few distinguishing characters. Callionymus belongs to the ‘benthic associated clade’ of the order Syngnathiformes. The ‘benthic associated clade’ so far is not represented by genome data and serves as an important outgroup to understand the morphological transformation in ‘long-snouted’ syngnatiformes such as seahorses and pipefishes. Findings Here, we present the chromosome-level genome assembly of C. lyra. We applied Oxford Nanopore Technologies’ long-read sequencing, short-read DNBseq, and proximity-ligation-based scaffolding to generate a high-quality genome assembly. The resulting assembly has a contig N50 of 2.2 Mbp and a scaffold N50 of 26.7 Mbp. The total assembly length is 568.7 Mbp, of which over 538 Mbp were scaffolded into 19 chromosome-length scaffolds. The identification of 94.5% complete BUSCO genes indicates high assembly completeness. Additionally, we sequenced and assembled a multi-tissue transcriptome with a total length of 255.5 Mbp that was used to aid the annotation of the genome assembly. The annotation resulted in 19,849 annotated transcripts and identified a repeat content of 27.7%. Conclusions The chromosome-level assembly of C. lyra provides a high-quality reference genome for future population genomic, phylogenomic, and phylogeographic analyses.
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- 2020
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14. Gene flow analysis method, the D-statistic, is robust in a wide parameter space
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Yichen Zheng and Axel Janke
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Gene flow ,The D-statistic ,Sensitivity ,Population size ,Parameter space ,Simulation ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background We evaluated the sensitivity of the D-statistic, a parsimony-like method widely used to detect gene flow between closely related species. This method has been applied to a variety of taxa with a wide range of divergence times. However, its parameter space and thus its applicability to a wide taxonomic range has not been systematically studied. Divergence time, population size, time of gene flow, distance of outgroup and number of loci were examined in a sensitivity analysis. Result The sensitivity study shows that the primary determinant of the D-statistic is the relative population size, i.e. the population size scaled by the number of generations since divergence. This is consistent with the fact that the main confounding factor in gene flow detection is incomplete lineage sorting by diluting the signal. The sensitivity of the D-statistic is also affected by the direction of gene flow, size and number of loci. In addition, we examined the ability of the f-statistics, f ̂ G $$ {\widehat{f}}_G $$ and f ̂ hom $$ {\widehat{f}}_{hom} $$ , to estimate the fraction of a genome affected by gene flow; while these statistics are difficult to implement to practical questions in biology due to lack of knowledge of when the gene flow happened, they can be used to compare datasets with identical or similar demographic background. Conclusions The D-statistic, as a method to detect gene flow, is robust against a wide range of genetic distances (divergence times) but it is sensitive to population size. The D-statistic should only be applied with critical reservation to taxa where population sizes are large relative to branch lengths in generations.
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- 2018
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15. Bioacoustics Reveal Hidden Diversity in Frogs: Two New Species of the Genus Limnonectes from Myanmar (Amphibia, Anura, Dicroglossidae)
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Gunther Köhler, Britta Zwitzers, Ni Lar Than, Deepak Kumar Gupta, Axel Janke, Steffen U. Pauls, and Panupong Thammachoti
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bioacoustics ,cryptic species diversity ,Dicroglossidae ,genome ,Limnonectes bagoensis sp. nov. ,Limnonectes bagoyoma sp. nov. ,Biology (General) ,QH301-705.5 - Abstract
Striking geographic variation in male advertisement calls was observed in frogs formerly referred to as Limnonectes doriae and L. limborgi, respectively. Subsequent analyses of mtDNA and external morphological data brought supporting evidence for the recognition of these populations as distinct species. We describe two new frog species of the genus Limnonectes (i.e., L. bagoensis sp. nov. and L. bagoyoma sp. nov.) from Myanmar. Limnonectes bagoensis sp. nov. is closely related to L. doriae whereas L. bagoyoma sp. nov. is closely related to L. limborgi. Results of this integrative study provide evidence for the presence of additional undescribed species in these species complexes but due to the lack of bioacoustical data, we consider these additional diverging populations as candidate species that need further study to resolve their respective taxonomic status. Both new species are distributed in Lower Myanmar. Limnonectes doriae is restricted to southern Myanmar along the Malayan Peninsula whereas L. limborgi is known to occur in eastern Myanmar and northwestern Thailand. The remaining populations formerly referred to as either L. doriae or L. limborgi are considered representatives of various candidate species that await further study. We further provide a de novo draft genome of the respective holotypes of L. bagoensis sp. nov. and L. bagoyoma sp. nov. based on short-read sequencing technology to 25-fold coverage.
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- 2021
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16. Screening for the ancient polar bear mitochondrial genome reveals low integration of mitochondrial pseudogenes (numts) in bears
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Fritjof Lammers, Axel Janke, Cornelia Rücklé, Vera Zizka, and Maria A. Nilsson
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mitochondrial genome ,numt ,ursidae ,polar bear ,panda ,pseudogene ,Genetics ,QH426-470 - Abstract
Phylogenetic analyses of nuclear and mitochondrial genomes indicate that polar bears captured the brown bear mitochondrial genome 160,000 years ago, leading to an extinction of the original polar bear mitochondrial genome. However, mitochondrial DNA occasionally integrates into the nuclear genome, forming pseudogenes called numts (nuclear mitochondrial integrations). Screening the polar bear genome identified only 13 numts. Genomic analyses of two additional ursine bears and giant panda indicate that all except one of the discovered numts entered the bear lineage at least 14 million years ago. However, short read genome assemblies might lead to an under-representation of numts or other repetitive sequences. Our findings suggest low integration rates of numts in bears and a loss of the original polar bear mitochondrial genome.
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- 2017
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17. Genetic evidence supports a distinct lineage of American crocodile (Crocodylus acutus) in the Greater Antilles
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Yoamel Milián-García, Michael A. Russello, Jessica Castellanos-Labarcena, Martin Cichon, Vikas Kumar, Georgina Espinosa, Natalia Rossi, Frank Mazzotti, Evon Hekkala, George Amato, and Axel Janke
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Crocodylus acutus ,American crocodile ,mtDNA ,Phylogeny ,Cryptic species ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Four species of true crocodile (genus Crocodylus) have been described from the Americas. Three of these crocodile species exhibit non-overlapping distributions—Crocodylus intermedius in South America, C. moreletii along the Caribbean coast of Mesoamerica, and C. rhombifer confined to Cuba. The fourth, C. acutus, is narrowly sympatric with each of the other three species. In this study, we sampled 113 crocodiles across Crocodylus populations in Cuba, as well as exemplar populations in Belize and Florida (USA), and sequenced three regions of the mitochondrial genome (D-loop, cytochrome b, cytochrome oxidase I; 3,626 base pair long dataset) that overlapped with published data previously collected from Colombia, Jamaica, and the Cayman Islands. Phylogenetic analyses of these data revealed two, paraphyletic lineages of C. acutus. One lineage, found in the continental Americas, is the sister taxon to C. intermedius, while the Greater Antillean lineage is most closely related to C. rhombifer. In addition to the paraphyly of the two C. acutus lineages, we recovered a 5.4% estimate of Tamura-Nei genetic divergence between the Antillean and continental clades. The reconstructed paraphyly, distinct phylogenetic affinities and high genetic divergence between Antillean and continental C. acutus populations are consistent with interspecific differentiation within the genus and suggest that the current taxon recognized as C. acutus is more likely a complex of cryptic species warranting a reassessment of current taxonomy. Moreover, the inclusion, for the first time, of samples from the western population of the American crocodile in Cuba revealed evidence for continental mtDNA haplotypes in the Antilles, suggesting this area may constitute a transition zone between distinct lineages of C. acutus. Further study using nuclear character data is warranted to more fully characterize this cryptic diversity, resolve taxonomic uncertainty, and inform conservation planning in this system.
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- 2018
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18. Cryptic population structuring and the role of the Isthmus of Tehuantepec as a gene flow barrier in the critically endangered Central American River Turtle.
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Gracia P González-Porter, Jesús E Maldonado, Oscar Flores-Villela, Richard C Vogt, Axel Janke, Robert C Fleischer, and Frank Hailer
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Medicine ,Science - Abstract
The critically endangered Central American River Turtle (Dermatemys mawii) is the only remaining member of the Dermatemydidae family, yet little is known about its population structuring. In a previous study of mitochondrial (mt) DNA in the species, three main lineages were described. One lineage (Central) was dominant across most of the range, while two other lineages were restricted to Papaloapan (PAP; isolated by the Isthmus of Tehuantepec and the Sierra de Santa Marta) or the south-eastern part of the range (1D). Here we provide data from seven polymorphic microsatellite loci and the R35 intron to re-evaluate these findings using DNA from the nuclear genome. Based on a slightly expanded data set of a total of 253 samples from the same localities, we find that mtDNA and nuclear DNA markers yield a highly congruent picture of the evolutionary history and population structuring of D. mawii. While resolution provided by the R35 intron (sequenced for a subset of the samples) was very limited, the microsatellite data revealed pronounced population structuring. Within the Grijalva-Usumacinta drainage basin, however, many populations separated by more than 300 kilometers showed signals of high gene flow. Across the entire range, neither mitochondrial nor nuclear DNA show a significant isolation-by-distance pattern, but both genomes highlight that the D. mawii population in the Papaloapan basin is genetically distinctive. Further, both marker systems detect unique genomic signals in four individuals with mtDNA clade 1D sampled on the southeast edge of the Grijalva-Usumacinta basin. These individuals may represent a separate cryptic taxon that is likely impacted by recent admixture.
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- 2013
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19. Coalescent-based genome analyses resolve the early branches of the euarchontoglires.
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Vikas Kumar, Björn M Hallström, and Axel Janke
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Medicine ,Science - Abstract
Despite numerous large-scale phylogenomic studies, certain parts of the mammalian tree are extraordinarily difficult to resolve. We used the coding regions from 19 completely sequenced genomes to study the relationships within the super-clade Euarchontoglires (Primates, Rodentia, Lagomorpha, Dermoptera and Scandentia) because the placement of Scandentia within this clade is controversial. The difficulty in resolving this issue is due to the short time spans between the early divergences of Euarchontoglires, which may cause incongruent gene trees. The conflict in the data can be depicted by network analyses and the contentious relationships are best reconstructed by coalescent-based analyses. This method is expected to be superior to analyses of concatenated data in reconstructing a species tree from numerous gene trees. The total concatenated dataset used to study the relationships in this group comprises 5,875 protein-coding genes (9,799,170 nucleotides) from all orders except Dermoptera (flying lemurs). Reconstruction of the species tree from 1,006 gene trees using coalescent models placed Scandentia as sister group to the primates, which is in agreement with maximum likelihood analyses of concatenated nucleotide sequence data. Additionally, both analytical approaches favoured the Tarsier to be sister taxon to Anthropoidea, thus belonging to the Haplorrhine clade. When divergence times are short such as in radiations over periods of a few million years, even genome scale analyses struggle to resolve phylogenetic relationships. On these short branches processes such as incomplete lineage sorting and possibly hybridization occur and make it preferable to base phylogenomic analyses on coalescent methods.
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- 2013
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20. Impact of carnivory on human development and evolution revealed by a new unifying model of weaning in mammals.
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Elia Psouni, Axel Janke, and Martin Garwicz
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Medicine ,Science - Abstract
Our large brain, long life span and high fertility are key elements of human evolutionary success and are often thought to have evolved in interplay with tool use, carnivory and hunting. However, the specific impact of carnivory on human evolution, life history and development remains controversial. Here we show in quantitative terms that dietary profile is a key factor influencing time to weaning across a wide taxonomic range of mammals, including humans. In a model encompassing a total of 67 species and genera from 12 mammalian orders, adult brain mass and two dichotomous variables reflecting species differences regarding limb biomechanics and dietary profile, accounted for 75.5%, 10.3% and 3.4% of variance in time to weaning, respectively, together capturing 89.2% of total variance. Crucially, carnivory predicted the time point of early weaning in humans with remarkable precision, yielding a prediction error of less than 5% with a sample of forty-six human natural fertility societies as reference. Hence, carnivory appears to provide both a necessary and sufficient explanation as to why humans wean so much earlier than the great apes. While early weaning is regarded as essentially differentiating the genus Homo from the great apes, its timing seems to be determined by the same limited set of factors in humans as in mammals in general, despite some 90 million years of evolution. Our analysis emphasizes the high degree of similarity of relative time scales in mammalian development and life history across 67 genera from 12 mammalian orders and shows that the impact of carnivory on time to weaning in humans is quantifiable, and critical. Since early weaning yields shorter interbirth intervals and higher rates of reproduction, with profound effects on population dynamics, our findings highlight the emergence of carnivory as a process fundamentally determining human evolution.
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- 2012
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21. A genomic approach to examine the complex evolution of laurasiatherian mammals.
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Björn M Hallström, Adrian Schneider, Stefan Zoller, and Axel Janke
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Medicine ,Science - Abstract
Recent phylogenomic studies have failed to conclusively resolve certain branches of the placental mammalian tree, despite the evolutionary analysis of genomic data from 32 species. Previous analyses of single genes and retroposon insertion data yielded support for different phylogenetic scenarios for the most basal divergences. The results indicated that some mammalian divergences were best interpreted not as a single bifurcating tree, but as an evolutionary network. In these studies the relationships among some orders of the super-clade Laurasiatheria were poorly supported, albeit not studied in detail. Therefore, 4775 protein-coding genes (6,196,263 nucleotides) were collected and aligned in order to analyze the evolution of this clade. Additionally, over 200,000 introns were screened in silico, resulting in 32 phylogenetically informative long interspersed nuclear elements (LINE) insertion events. The present study shows that the genome evolution of Laurasiatheria may best be understood as an evolutionary network. Thus, contrary to the common expectation to resolve major evolutionary events as a bifurcating tree, genome analyses unveil complex speciation processes even in deep mammalian divergences. We exemplify this on a subset of 1159 suitable genes that have individual histories, most likely due to incomplete lineage sorting or introgression, processes that can make the genealogy of mammalian genomes complex. These unexpected results have major implications for the understanding of evolution in general, because the evolution of even some higher level taxa such as mammalian orders may sometimes not be interpreted as a simple bifurcating pattern.
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- 2011
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22. Phylogenetic Analysis of Kindlins Suggests Subfunctionalization of an Ancestral Unduplicated Kindlin into Three Paralogs in Vertebrates
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Ammad Aslam Khan, Axel Janke, Takashi Shimokawa, and Hongquan Zhang
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Evolution ,QH359-425 - Abstract
Kindlin proteins represent a newly discovered family of evolutionarily conserved FERM domain-containing proteins. This family includes three highly conserved proteins: Kindlin-1, Kindlin-2 and Kindlin-3. All three Kindlin proteins are associated with focal adhesions and are involved in integrin activation. The FERM domain of each Kindlin is bipartite and plays a key role in integrin activation. We herein explore for the first time the evolutionary history of these proteins. The phylogeny of the Kindlins suggests a single ancestral Kindlin protein present in even the earliest metazoan ie, hydra. This protein then underwent duplication events in insects and also experienced genome duplication in vertebrates, leading to the Kindlin family. A comparative study of the Kindlin paralogs showed that Kindlin-2 is the slowest evolving protein among the three family members. The analysis of synonymous and non-synonymous substitutions in orthologous Kindlin sequences in different species showed that all three Kindlins have been evolving under the influence of purifying selection. The expression pattern of Kindlins along with phylogenetic studies supports the subfunctionalization model of gene duplication.
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- 2011
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23. Expressed sequence tags as a tool for phylogenetic analysis of placental mammal evolution.
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Morgan Kullberg, Björn Hallström, Ulfur Arnason, and Axel Janke
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Medicine ,Science - Abstract
BackgroundWe investigate the usefulness of expressed sequence tags, ESTs, for establishing divergences within the tree of placental mammals. This is done on the example of the established relationships among primates (human), lagomorphs (rabbit), rodents (rat and mouse), artiodactyls (cow), carnivorans (dog) and proboscideans (elephant).Methodology/principal findingsWe have produced 2000 ESTs (1.2 mega bases) from a marsupial mouse and characterized the data for their use in phylogenetic analysis. The sequences were used to identify putative orthologous sequences from whole genome projects. Although most ESTs stem from single sequence reads, the frequency of potential sequencing errors was found to be lower than allelic variation. Most of the sequences represented slowly evolving housekeeping-type genes, with an average amino acid distance of 6.6% between human and mouse. Positive Darwinian selection was identified at only a few single sites. Phylogenetic analyses of the EST data yielded trees that were consistent with those established from whole genome projects.ConclusionsThe general quality of EST sequences and the general absence of positive selection in these sequences make ESTs an attractive tool for phylogenetic analysis. The EST approach allows, at reasonable costs, a fast extension of data sampling from species outside the genome projects.
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- 2007
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24. A chromosome-scale reference genome assembly of the great sand eel, Hyperoplus lanceolatus
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Sven Winter, Jordi de Raad, Magnus Wolf, Raphael T F Coimbra, Menno J de Jong, Yannis Schöneberg, Maria Christoph, Hagen von Klopotek, Katharina Bach, Behgol Pashm Foroush, Wiebke Hanack, Aaron Hagen Kauffeldt, Tim Milz, Emmanuel Kipruto Ngetich, Christian Wenz, Moritz Sonnewald, Maria Anna Nilsson, and Axel Janke
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Genetics ,Molecular Biology ,Genetics (clinical) ,Biotechnology - Abstract
Despite increasing sequencing efforts, numerous fish families still lack a reference genome, which complicates genetic research. One such understudied family is the sand lances (Ammodytidae, literally: “sand burrower”), a globally distributed clade of over 30 fish species that tend to avoid tidal currents by burrowing into the sand. Here, we present the first annotated chromosome-level genome assembly of the great sand eel (Hyperoplus lanceolatus). The genome assembly was generated using Oxford Nanopore Technologies long sequencing reads and Illumina short reads for polishing. The final assembly has a total length of 808.5 Mbp, of which 97.1% were anchored into 24 chromosome-scale scaffolds using proximity-ligation scaffolding. It is highly contiguous with a scaffold and contig N50 of 33.7 and 31.3 Mbp, respectively, and has a BUSCO completeness score of 96.9%. The presented genome assembly is a valuable resource for future studies of sand lances, as this family is of great ecological and commercial importance and may also contribute to studies aiming to resolve the suprafamiliar taxonomy of bony fishes.
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- 2023
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25. A Chromosome-Scale Genome Assembly of the Okapi (Okapia Johnstoni)
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Sven Winter, Raphael T F Coimbra, Philippe Helsen, and Axel Janke
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Genome ,Genetics ,Animals ,Giraffes ,Genomics ,Sequence Analysis, DNA ,Molecular Biology ,Chromosomes ,Genetics (clinical) ,Biotechnology - Abstract
The okapi (Okapia johnstoni), or forest giraffe, is the only species in its genus and the only extant sister group of the giraffe within the family Giraffidae. The species is one of the remaining large vertebrates surrounded by mystery because of its elusive behavior as well as the armed conflicts in the region where it occurs, making it difficult to study. Deforestation puts the okapi under constant anthropogenic pressure, and it is currently listed as “Endangered” on the IUCN Red List. Here, we present the first annotated de novo okapi genome assembly based on PacBio continuous long reads, polished with short reads, and anchored into chromosome-scale scaffolds using Hi-C proximity ligation sequencing. The final assembly (TBG_Okapi_asm_v1) has a length of 2.39 Gbp, of which 98% are represented by 28 scaffolds > 3.9 Mbp. The contig N50 of 61 Mbp and scaffold N50 of 102 Mbp, together with a BUSCO score of 94.7%, and 23 412 annotated genes, underline the high quality of the assembly. This chromosome-scale genome assembly is a valuable resource for future conservation of the species and comparative genomic studies among the giraffids and other ruminants.
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- 2022
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26. Seascape genomics and phylogeography of the sailfish (Istiophorus platypterus)
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Bruno Lopes da Silva Ferrette, Raphael T F Coimbra, Sven Winter, Menno J De Jong, Samuel Mackey Williams, Rui Coelho, Daniela Rosa, Matheus Marcos Rotundo, Freddy Arocha, Bruno Leite Mourato, Fernando Fernandes Mendonça, and Axel Janke
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Demographic history ,Whole-genome sequencing ,Reference genome assembly ,Genetics ,Genome-wide heterozygosity ,Fisheries management units ,Ecology, Evolution, Behavior and Systematics - Abstract
Permeable phylogeographic barriers characterize the vast open ocean, boosting gene flow and counteracting population differentiation and speciation of widely distributed and migratory species. However, many widely distributed species consists of distinct populations throughout their distribution, evidencing that our understanding of how the marine environment triggers population and species divergence are insufficient. The sailfish is a circumtropical and highly migratory billfish that inhabits warm and productive areas. Despite its ecological and socioeconomic importance as a predator and fishery resource, the species is threatened by overfishing, requiring innovative approaches to improve their management and conservation status. Thus, we presented a novel high-quality reference genome for the species and applied a seascape genomics approach to understand how marine environmental features may promote local adaptation and how it affects gene flow between populations. We delimit two populations between the Atlantic and Indo-Western Pacific oceans and detect outlier loci correlated with sea surface temperature, salinity, oxygen, and chlorophyll concentrations. However, the most significant explanatory factor that explains the differences between populations was isolation by distance. Despite recent population drops, the sailfish populations are not inbred. For billfishes in general, genome-wide heterozygosity was found to be relatively low compared to other marine fishes, evidencing the need to counteract overfishing effects. In addition, in a climate change scenario, management agencies must implement state-of-the-art sequencing methods, consider our findings in their management plans, and monitor genome-wide heterozygosity over time to improve sustainable fisheries and the long-term viability of its populations.
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- 2023
27. Genomics reveals broad hybridization in deeply divergent Palearctic grass and water snakes (Natrix spp.)
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Yannis Schöneberg, Sven Winter, Oscar Arribas, Matteo Riccardo Di Nicola, Maya Master, John Benjamin Owens, Michail Rovatsos, Wolfgang Wüster, Axel Janke, and Uwe Fritz
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Genetics ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics - Published
- 2023
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28. Genomic Impact of Whaling in North Atlantic Fin Whales
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Magnus Wolf, Menno de Jong, Sverrir Daníel Halldórsson, Úlfur Árnason, and Axel Janke
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Population Density ,Genome ,Fin Whale ,Genetics ,Whales ,Animals ,Genomics ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics - Abstract
It is generally recognized that large-scale whaling in the 19th and 20th century led to a substantial reduction of the size of many cetacean populations, particularly those of the baleen whales (Mysticeti). The impact of these operations on genomic diversity of one of the most hunted whales, the fin whale (Balaenoptera physalus), has remained largely unaddressed because of the paucity of adequate samples and the limitation of applicable techniques. Here, we have examined the effect of whaling on the North Atlantic fin whale based on genomes of 51 individuals from Icelandic waters, representing three temporally separated intervals, 1989, 2009 and 2018 and provide a reference genome for the species. Demographic models suggest a noticeable drop of the effective population size of the North Atlantic fin whale around a century ago. The present results suggest that the genome-wide heterozygosity is not markedly reduced and has remained comparable with other baleen whale species. Similarly, there are no signs of apparent inbreeding, as measured by the proportion of long runs of homozygosity, or of a distinctively increased mutational load, as measured by the amount of putative deleterious mutations. Compared with other baleen whales, the North Atlantic fin whale appears to be less affected by anthropogenic influences than other whales such as the North Atlantic right whale, consistent with the presence of long runs of homozygosity and higher levels of mutational load in an otherwise more heterozygous genome. Thus, genome-wide assessments of other species and populations are essential for future, more specific, conservation efforts.
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- 2022
29. Gene losses in the common vampire bat illuminate molecular adaptations to blood feeding
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M. Foote, A.-W. Ahmed, Ana Luiza Fonseca Destro, B. K. Lim, Nikolai Hecker, Martin Pippel, M. Bontempo Freitas, A. Morales, T. Brown, Michael Hiller, Tilman Schell, Axel Janke, B. Kirilenko, M. Blumer, J. A. Oliveira, David Jebb, and Carola Greve
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EXPRESSION ,CHOLESTEROL 24-HYDROXYLASE ,Lineage (genetic) ,Acclimatization ,Biology ,FUNCTIONAL-PROPERTIES ,INSULIN-SECRETION ,Genome ,Chiroptera ,Animals ,RAB15 EFFECTOR PROTEIN ,FATTY-ACID RECEPTOR ,Gene ,Science & Technology ,Multidisciplinary ,Obligate ,IRON ,Vampire ,MICE REVEALS ,biology.organism_classification ,Adaptation, Physiological ,Diet ,GLYCOGEN-SYNTHESIS ,Multidisciplinary Sciences ,ZINC TRANSPORTER ,Evolutionary biology ,Vampire bat ,Desmodus rotundus ,CYP39A1 ,Science & Technology - Other Topics - Abstract
Feeding exclusively on blood, vampire bats represent the only obligate sanguivorous lineage among mammals. To uncover genomic changes associated with adaptations to this unique dietary specialization, we generated a new haplotype-resolved reference-quality genome of the common vampire bat (Desmodus rotundus) and screened 26 bat species for genes that were specifically lost in the vampire bat lineage. We discovered previously-unknown gene losses that relate to metabolic and physiological changes, such as reduced insulin secretion (FFAR1,SLC30A8), limited glycogen stores (PPP1R3E), and a distinct gastric physiology (CTSE). Other gene losses likely reflect the biased nutrient composition (ERN2,CTRL) and distinct pathogen diversity of blood (RNASE7). Interestingly, the loss ofREP15likely helped vampire bats to adapt to high dietary iron levels by enhancing iron excretion and the loss of the 24S-hydroxycholesterol metabolizing enzymeCYP39A1could contribute to their exceptional cognitive abilities. Finally, losses of key cone phototransduction genes (PDE6H,PDE6C) suggest that these strictly-nocturnal bats completely lack cone-based vision. These findings enhance our understanding of vampire bat biology and the genomic underpinnings of adaptations to sanguivory.
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- 2022
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30. The Earth BioGenome Project 2020: Starting the clock
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Harris A. Lewin, Stephen Richards, Erez Lieberman Aiden, Miguel L. Allende, John M. Archibald, Miklós Bálint, Katharine B. Barker, Bridget Baumgartner, Katherine Belov, Giorgio Bertorelle, Mark L. Blaxter, Jing Cai, Nicolette D. Caperello, Keith Carlson, Juan Carlos Castilla-Rubio, Shu-Miaw Chaw, Lei Chen, Anna K. Childers, Jonathan A. Coddington, Dalia A. Conde, Montserrat Corominas, Keith A. Crandall, Andrew J. Crawford, Federica DiPalma, Richard Durbin, ThankGod E. Ebenezer, Scott V. Edwards, Olivier Fedrigo, Paul Flicek, Giulio Formenti, Richard A. Gibbs, M. Thomas P. Gilbert, Melissa M. Goldstein, Jennifer Marshall Graves, Henry T. Greely, Igor V. Grigoriev, Kevin J. Hackett, Neil Hall, David Haussler, Kristofer M. Helgen, Carolyn J. Hogg, Sachiko Isobe, Kjetill Sigurd Jakobsen, Axel Janke, Erich D. Jarvis, Warren E. Johnson, Steven J. M. Jones, Elinor K. Karlsson, Paul J. Kersey, Jin-Hyoung Kim, W. John Kress, Shigehiro Kuraku, Mara K. N. Lawniczak, James H. Leebens-Mack, Xueyan Li, Kerstin Lindblad-Toh, Xin Liu, Jose V. Lopez, Tomas Marques-Bonet, Sophie Mazard, Jonna A. K. Mazet, Camila J. Mazzoni, Eugene W. Myers, Rachel J. O’Neill, Sadye Paez, Hyun Park, Gene E. Robinson, Cristina Roquet, Oliver A. Ryder, Jamal S. M. Sabir, H. Bradley Shaffer, Timothy M. Shank, Jacob S. Sherkow, Pamela S. Soltis, Boping Tang, Leho Tedersoo, Marcela Uliano-Silva, Kun Wang, Xiaofeng Wei, Regina Wetzer, Julia L. Wilson, Xun Xu, Huanming Yang, Anne D. Yoder, Guojie Zhang, Lewin, Harris A [0000-0002-1043-7287], Richards, Stephen [0000-0001-8959-5466], Allende, Miguel L [0000-0002-2783-2152], Blaxter, Mark L [0000-0003-2861-949X], Coddington, Jonathan A [0000-0001-6004-7730], Conde, Dalia A [0000-0002-7923-8163], Corominas, Montserrat [0000-0002-0724-8346], Crandall, Keith A [0000-0002-0836-3389], Durbin, Richard [0000-0002-9130-1006], Edwards, Scott V [0000-0003-2535-6217], Gilbert, M Thomas P [0000-0002-5805-7195], Graves, Jennifer Marshall [0000-0001-6480-7856], Greely, Henry T [0000-0002-1105-6734], Grigoriev, Igor V [0000-0002-3136-8903], Hogg, Carolyn J [0000-0002-6328-398X], Jakobsen, Kjetill Sigurd [0000-0002-8861-5397], Janke, Axel [0000-0002-9394-1904], Johnson, Warren E [0000-0002-5954-186X], Karlsson, Elinor K [0000-0002-4343-3776], Kress, W John [0000-0002-0140-5267], Leebens-Mack, James H [0000-0003-4811-2231], Lindblad-Toh, Kerstin [0000-0001-8338-0253], Marques-Bonet, Tomas [0000-0002-5597-3075], Mazet, Jonna AK [0000-0002-8712-5951], Myers, Eugene W [0000-0002-6580-7839], Robinson, Gene E [0000-0003-4828-4068], Roquet, Cristina [0000-0001-8748-3743], Ryder, Oliver A [0000-0003-2427-763X], Sabir, Jamal SM [0000-0003-4785-9894], Shaffer, H Bradley [0000-0002-5795-9242], Sherkow, Jacob S [0000-0002-9724-9261], Soltis, Pamela S [0000-0001-9310-8659], Tang, Boping [0000-0002-3241-7914], Yoder, Anne D [0000-0002-1781-9552], Zhang, Guojie [0000-0001-6860-1521], and Apollo - University of Cambridge Repository
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Introduction ,Multidisciplinary ,Base Sequence ,Evolution ,Botany ,Ambientale ,Eukaryota ,Genomics ,Botanik ,Biodiversity ,Biological Sciences ,Biodiversitat ,Biodiversity [MeSH] ,Genomics [MeSH] ,Eukaryota/genetics [MeSH] ,Humans [MeSH] ,Base Sequence/genetics [MeSH] ,Animals [MeSH] ,Animals ,Humans ,The Earth BioGenome Project: The Launch of a Moonshot for Biology ,Genomes ,Uncategorized - Abstract
November 2020 marked 2 y since the launch of the Earth BioGenome Project (EBP), which aims to sequence all known eukaryotic species in a 10-y timeframe. Since then, significant progress has been made across all aspects of the EBP roadmap, as outlined in the 2018 article describing the project's goals, strategies, and challenges (1). The launch phase has ended and the clock has started on reaching the EBP's major milestones. This Special Feature explores the many facets of the EBP, including a review of progress, a description of major scientific goals, exemplar projects, ethical legal and social issues, and applications of biodiversity genomics. In this Introduction, we summarize the current status of the EBP, held virtually October 5 to 9, 2020, including recent updates through February 2021. References to the nine Perspective articles included in this Special Feature are cited to guide the reader toward deeper understanding of the goals and challenges facing the EBP.
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- 2022
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31. Bioacoustics Reveal Hidden Diversity in Frogs: Two New Species of the Genus Limnonectes from Myanmar (Amphibia, Anura, Dicroglossidae)
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Ni Lar Than, Deepak K. Gupta, Steffen U. Pauls, Panupong Thammachoti, Axel Janke, Gunther Köhler, and Britta Zwitzers
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new species ,Mitochondrial DNA ,Limnonectes bagoyoma sp. nov ,Dicroglossidae ,Ecology ,biology ,QH301-705.5 ,Ecological Modeling ,Zoology ,Geographic variation ,Myanmar ,biology.organism_classification ,Thailand ,Agricultural and Biological Sciences (miscellaneous) ,Genome ,bioacoustics ,cryptic species diversity ,Genus ,Limnonectes ,Limnonectes bagoensis sp. nov ,Biology (General) ,genome ,Nature and Landscape Conservation - Abstract
Striking geographic variation in male advertisement calls was observed in frogs formerly referred to as Limnonectes doriae and L. limborgi, respectively. Subsequent analyses of mtDNA and external morphological data brought supporting evidence for the recognition of these populations as distinct species. We describe two new frog species of the genus Limnonectes (i.e., L. bagoensis sp. nov. and L. bagoyoma sp. nov.) from Myanmar. Limnonectes bagoensis sp. nov. is closely related to L. doriae whereas L. bagoyoma sp. nov. is closely related to L. limborgi. Results of this integrative study provide evidence for the presence of additional undescribed species in these species complexes but due to the lack of bioacoustical data, we consider these additional diverging populations as candidate species that need further study to resolve their respective taxonomic status. Both new species are distributed in Lower Myanmar. Limnonectes doriae is restricted to southern Myanmar along the Malayan Peninsula whereas L. limborgi is known to occur in eastern Myanmar and northwestern Thailand. The remaining populations formerly referred to as either L. doriae or L. limborgi are considered representatives of various candidate species that await further study. We further provide a de novo draft genome of the respective holotypes of L. bagoensis sp. nov. and L. bagoyoma sp. nov. based on short-read sequencing technology to 25-fold coverage.
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- 2021
32. Two high-quality de novo genomes from single ethanol-preserved specimens of tiny metazoans (Collembola)
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Bruno Huettel, Axel Janke, Cyrille A. D’Haese, Christian Woehle, Carola Greve, Michael Hiller, Magnus Wolf, Clément Schneider, Miklós Bálint, LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Partenaires INRAE, Max Planck Institute for Plant Breeding Research (MPIPZ), Mécanismes Adaptatifs et Evolution (MECADEV), and Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)
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0106 biological sciences ,AcademicSubjects/SCI02254 ,Biodiversity ,Health Informatics ,Genomics ,Biology ,[SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy ,Data Note ,010603 evolutionary biology ,01 natural sciences ,Genome ,DNA sequencing ,03 medical and health sciences ,eukaryote biodiversity ,Phylogenetics ,low-input DNA ,Animals ,Gene ,Arthropods ,integrative taxonomy ,030304 developmental biology ,PacBio ,0303 health sciences ,Contig ,Ethanol ,[SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE] ,High-Throughput Nucleotide Sequencing ,[SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology ,Sequence Analysis, DNA ,long-read genome sequencing ,soil invertebrates ,Computer Science Applications ,[SDV.BA.ZI]Life Sciences [q-bio]/Animal biology/Invertebrate Zoology ,Evolutionary biology ,AcademicSubjects/SCI00960 ,Taxonomy (biology) ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology - Abstract
Background Genome sequencing of all known eukaryotes on Earth promises unprecedented advances in biological sciences and in biodiversity-related applied fields such as environmental management and natural product research. Advances in long-read DNA sequencing make it feasible to generate high-quality genomes for many non–genetic model species. However, long-read sequencing today relies on sizable quantities of high-quality, high molecular weight DNA, which is mostly obtained from fresh tissues. This is a challenge for biodiversity genomics of most metazoan species, which are tiny and need to be preserved immediately after collection. Here we present de novo genomes of 2 species of submillimeter Collembola. For each, we prepared the sequencing library from high molecular weight DNA extracted from a single specimen and using a novel ultra-low input protocol from Pacific Biosciences. This protocol requires a DNA input of only 5 ng, permitted by a whole-genome amplification step. Results The 2 assembled genomes have N50 values >5.5 and 8.5 Mb, respectively, and both contain ∼96% of BUSCO genes. Thus, they are highly contiguous and complete. The genomes are supported by an integrative taxonomy approach including placement in a genome-based phylogeny of Collembola and designation of a neotype for 1 of the species. Higher heterozygosity values are recorded in the more mobile species. Both species are devoid of the biosynthetic pathway for β-lactam antibiotics known in several Collembola, confirming the tight correlation of antibiotic synthesis with the species way of life. Conclusions It is now possible to generate high-quality genomes from single specimens of minute, field-preserved metazoans, exceeding the minimum contig N50 (1 Mb) required by the Earth BioGenome Project.
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- 2021
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33. Screening for the ancient polar bear mitochondrial genome reveals low integration of mitochondrial pseudogenes (
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Fritjof, Lammers, Axel, Janke, Cornelia, Rücklé, Vera, Zizka, and Maria A, Nilsson
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Mito Communication ,polar bear ,numt ,Mitochondrial genome ,panda ,pseudogene ,Ursidae ,Research Article - Abstract
Phylogenetic analyses of nuclear and mitochondrial genomes indicate that polar bears captured the brown bear mitochondrial genome 160,000 years ago, leading to an extinction of the original polar bear mitochondrial genome. However, mitochondrial DNA occasionally integrates into the nuclear genome, forming pseudogenes called numts (nuclear mitochondrial integrations). Screening the polar bear genome identified only 13 numts. Genomic analyses of two additional ursine bears and giant panda indicate that all except one of the discovered numts entered the bear lineage at least 14 million years ago. However, short read genome assemblies might lead to an under-representation of numts or other repetitive sequences. Our findings suggest low integration rates of numts in bears and a loss of the original polar bear mitochondrial genome.
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- 2021
34. A taxonomic revision of the genus Phrynoglossus in Indochina with the description of a new species and comments on the classification within Occidozyginae (Amphibia, Anura, Dicroglossidae)
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Ni Lar Than, Gunther Köhler, Joseph Vargas, Tilman Schell, Axel Janke, Panupong Thammachoti, and Steffen U. Pauls
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0106 biological sciences ,0301 basic medicine ,Computer science ,Zoology ,Myanmar ,amplexus mode ,010603 evolutionary biology ,01 natural sciences ,Khorat Plateau ,Aerugoamnis ,Amphibia ,bioacoustics ,cryptic species diversity ,03 medical and health sciences ,Phrynoglossus myanhessei sp. n ,Gnathostomata ,Genus ,Branchiostoma capense ,Animalia ,Chordata ,genome ,Ecology, Evolution, Behavior and Systematics ,Occidozyga ,Vertebrata ,Lissamphibia ,new species ,Craniata ,Dicroglossidae ,biology ,Ymeria ,Cephalornis ,biology.organism_classification ,Thailand ,030104 developmental biology ,QL1-991 ,Phrynoglossus ,Anura ,Occidozyginae - Abstract
We revise the frogs of the genusPhrynoglossusfrom Indochina based on data of external morphology, bioacoustics and molecular genetics. The results of this integrative study provide evidence for the recognition of three distinct species, one of which we describe as new.Phrynoglossus martensiihas a vast geographic distribution from central and southern Thailand across southern China to Vietnam, Laos, and Cambodia.Phrynoglossus myanhesseisp. nov.is distributed in central Myanmar whereasPhrynoglossus magnapustulosusis restricted to the Khorat Plateau, Thailand. These three species occur in allopatry and differ in their mating calls, external morphology, and in genetic distances of the 16S gene of 3.8–5.9%. Finally, we discuss and provide evolutionary evidence for the recognition ofPhrynoglossusas a genus distinct fromOccidozyga. Members of both genera form reciprocal monophyletic groups in our analyses of mtDNA data (16S) and are well differentiated from each other in morphology and ecology. Furthermore, they differ in the amplexus mode withPhrynoglossushaving an inguinal amplexus whereas it is axillary inOccidozyga. We further provide ade novodraft genome of the holotype based on short-read sequencing technology to a coverage of 25-fold. This resource will permanently link the genetic characterization of the species to the name-bearing type specimen.
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- 2021
35. Speciation and population divergence in a mutualistic seed dispersing bird
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Jordi de Raad, Martin Päckert, Martin Irestedt, Axel Janke, Alexey P. Kryukov, Jochen Martens, Yaroslav A. Red’kin, Yuehua Sun, Till Töpfer, Matthias Schleuning, Eike Lena Neuschulz, and Maria A. Nilsson
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Seed Dispersal ,Seeds ,Medicine (miscellaneous) ,Animals ,Passeriformes ,General Agricultural and Biological Sciences ,Pinus ,Symbiosis ,General Biochemistry, Genetics and Molecular Biology ,Ecosystem - Abstract
Bird-mediated seed dispersal is crucial for the regeneration and viability of ecosystems, often resulting in complex mutualistic species networks. Yet, how this mutualism drives the evolution of seed dispersing birds is still poorly understood. In the present study we combine whole genome re-sequencing analyses and morphometric data to assess the evolutionary processes that shaped the diversification of the Eurasian nutcracker (Nucifraga), a seed disperser known for its mutualism with pines (Pinus). Our results show that the divergence and phylogeographic patterns of nutcrackers resemble those of other non-mutualistic passerine birds and suggest that their early diversification was shaped by similar biogeographic and climatic processes. The limited variation in foraging traits indicates that local adaptation to pines likely played a minor role. Our study shows that close mutualistic relationships between bird and plant species might not necessarily act as a primary driver of evolution and diversification in resource-specialized birds.
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- 2021
36. A new genus and species of mud snake from Myanmar (Reptilia, Squamata Homalopsidae)
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Axel Janke, Damian Baranski, Carola Greve, Khin Pa Pa Khaing, Gunther Köhler, Steffen U. Pauls, Ni Lar Than, and Tilman Schell
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0106 biological sciences ,Male ,Squamata ,Reptilia ,010607 zoology ,Zoology ,Myanmar ,010603 evolutionary biology ,01 natural sciences ,DNA barcoding ,Genus ,Hemipenis ,Homalopsidae ,Animals ,Animalia ,Chordata ,Ecology, Evolution, Behavior and Systematics ,Ecosystem ,Phylogeny ,Taxonomy ,biology ,Holotype ,Subcaudal scales ,Animal Structures ,Lizards ,Dorsal scales ,Biodiversity ,biology.organism_classification ,Animal Science and Zoology ,Female ,Animal Distribution ,Ventral scales - Abstract
Based on two male and two female individuals, we describe a new genus and species of mud snake, Myanophis thanlyinensis gen. nov., sp. nov., from the vicinity of the campus of East Yangon University, Yangon, Thanlyin, Myanmar. This species differs from every other homalopsid species by the following combination of characters: (1) dorsal scales smooth, row formula 21–21–19 or 21–21–17; (2) tail short, ratio tail length/SVL 0.185–0.204 in males, 0.160–0.167 in females; (3) nasal scales separated; (4) 125–126 ventral scales in males, 120–122 in females; (5) 38–39 subcaudal scales in males, 32–34 in females; and (6) hemipenis bilobed. Its matrilineal genealogy (based on analyses of 16S and cytochrome b sequences), associates Myanophis thanlyinensis gen. nov., sp. nov. most closely with species of the genera Myrrophis and Gyiophis. The new taxon differs from the species of Myrrophis and Gyiophis by having a bilobed hemipenis (vs. unilobed). Myanophis thanlyinensis gen. nov., sp. nov. differs further from the species of Myrrophis by having 125–126 ventral scales in males and 120–122 in females (vs. 137–162 and 137–164, respectively), and 38–39 subcaudal scales in males and 32–34 in females (vs. 39–55 and 37–52, respectively). Myanophis thanlyinensis gen. nov., sp. nov. differs further from the species of Gyiophis by lacking dark blotches along flank (vs. present), and by having 21 dorsal scales rows at midbody (vs. 25). We provide an identification key to the homalopsid species known to occur in Myanmar. As a novelty to the classic holotype description and characterization, the individual has been genome sequenced by Illumina short-read technology and its genome has been assembled into a draft nuclear genome and a complete, annotated mitochondrial genome. This innovative approach comprehensively and permanently characterizes the genomic variation of the holotype.
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- 2021
37. SambaR: An R package for fast, easy and reproducible population‐genetic analyses of biallelic SNP data sets
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Axel Janke, Joost F. de Jong, A. Rus Hoelzel, and Menno J. de Jong
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0106 biological sciences ,0301 basic medicine ,Bayesian probability ,Population ,Biology ,Filter (higher-order function) ,computer.software_genre ,Polymorphism, Single Nucleotide ,010603 evolutionary biology ,01 natural sciences ,SNP data ,03 medical and health sciences ,Software ,Genetics ,SNP ,education ,Representation (mathematics) ,Alleles ,Ecology, Evolution, Behavior and Systematics ,Selection (genetic algorithm) ,education.field_of_study ,business.industry ,selection analyses ,R package ,population genetics ,Bayes Theorem ,genetic diversity ,population assignment test ,Data set ,Genetics, Population ,030104 developmental biology ,Wildlife Ecology and Conservation ,Data mining ,business ,gene flow ,computer ,Biotechnology - Abstract
SNP data sets can be used to infer a wealth of information about natural populations, including information about their structure, genetic diversity, and the presence of loci under selection. However, SNP data analysis can be a time-consuming and challenging process, not in the least because at present many different software packages are needed to execute and depict the wide variety of mainstream population-genetic analyses. Here, we present SambaR, an integrative and user-friendly R package which automates and simplifies quality control and population-genetic analyses of biallelic SNP data sets. SambaR allows users to perform mainstream population-genetic analyses and to generate a wide variety of ready to publish graphs with a minimum number of commands (less than 10). These wrapper commands call functions of existing packages (including adegenet, ape, LEA, poppr, pcadapt and StAMPP) as well as new tools uniquely implemented in SambaR. We tested SambaR on online available SNP data sets and found that SambaR can process data sets of over 100,000 SNPs and hundreds of individuals within hours, given sufficient computing power. Newly developed tools implemented in SambaR facilitate optimization of filter settings, objective interpretation of ordination analyses, enhance comparability of diversity estimates from reduced representation library SNP data sets, and generate reduced SNP panels and structure-like plots with Bayesian population assignment probabilities. SambaR facilitates rapid population genetic analyses on biallelic SNP data sets by removing three major time sinks: file handling, software learning, and data plotting. In addition, SambaR provides a convenient platform for SNP data storage and management, as well as several new utilities, including guidance in setting appropriate data filters. The SambaR source script, manual and example data set are distributed through GitHub: https://github.com/mennodejong1986/SambaR.
- Published
- 2021
- Full Text
- View/download PDF
38. Systematics, Evolution, and Genetics of Bears
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Eva Bellemain, Axel Janke, Alexander Kopatz, Andrew C. Kitchener, Xiang Ding, Valentina Salomashkina, Tabitha A. Graves, Manuel Ruiz-García, Verena E. Kutschera, Yiling Hou, and Lars Werdelin
- Subjects
Systematics ,Phylogeography ,Evolutionary biology ,Morphology (biology) ,Biology - Published
- 2020
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- View/download PDF
39. Chromosome-level genome assembly of a benthic associated Syngnathiformes species: the common dragonet, Callionymus lyra
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Axel Janke, Maximilian Murphy, Jordi De Raad, Stefan Prost, Raphael T. F. Coimbra, Sven Winter, Julian Bludau, Konstantin Zapf, Magnus Wolf, Annika Held, Melina Kurzawe, Monica M. Sheffer, Maria Nilsson, Yannis Schöneberg, Ramona Papapostolou, Moritz Sonnewald, David Prochotta, Jade Tessien, Sarah Gronefeld, Christian Zeitz, Marcel Nebenführ, and Andreas Kelch
- Subjects
0303 health sciences ,education.field_of_study ,biology ,Contig ,Callionymus ,Applied Mathematics ,General Mathematics ,Population ,Sequence assembly ,QA75.5-76.95 ,biology.organism_classification ,Genome ,03 medical and health sciences ,0302 clinical medicine ,Evolutionary biology ,Electronic computers. Computer science ,Syngnathiformes ,Clade ,education ,030217 neurology & neurosurgery ,030304 developmental biology ,Reference genome - Abstract
BackgroundThe common dragonet, Callionymus lyra, is one of three Callionymus species inhabiting the North Sea. All three species show strong sexual dimorphism. The males show strong morphological differentiation, e.g., species-specific colouration and size relations, while the females of different species have few distinguishing characters. Callionymus belongs to the ‘benthic associated clade’ of the order Syngnathiformes. The ‘benthic associated clade’ so far is not represented by genome data and serves as an important outgroup to understand the morphological transformation in ‘long-snouted’ syngnatiforms such as seahorses and pipefishes.FindingsHere, we present the chromosome-level genome assembly of C. lyra. We applied Oxford Nanopore Technologies’ long-read sequencing, short-read DNBseq, and proximity-ligation-based scaffolding to generate a high-quality genome assembly. The resulting assembly has a contig N50 of 2.2 Mbp, a scaffold N50 of 26.7 Mbp. The total assembly length is 568.7 Mbp, of which over 538 Mbp were scaffolded into 19 chromosome-length scaffolds. The identification of 94.5% of complete BUSCO genes indicates high assembly completeness. Additionally, we sequenced and assembled a multi-tissue transcriptome with a total length of 255.5 Mbp that was used to aid the annotation of the genome assembly. The annotation resulted in 19,849 annotated transcripts and identified a repeat content of 27.66%.ConclusionsThe chromosome-level assembly of C. lyra provides a high-quality reference genome for future population genomic, phylogenomic, and phylogeographic analyses.
- Published
- 2020
40. Biodiversity genomics of small metazoans: high quality de novo genomes from single specimens of field-collected and ethanol-preserved springtails
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Clément Schneider, Bruno Hüttel, Magnus Wolf, Carola Greve, Miklós Bálint, Axel Janke, Christian Woehle, and Cyrille A. D’Haese
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Systematics ,Mitochondrial DNA ,Nuclear gene ,Evolutionary biology ,Phylogenetics ,Biodiversity ,Genomics ,Biology ,Genome ,DNA sequencing - Abstract
Genome sequencing of all known eukaryotes on Earth promises unprecedented advances in evolutionary sciences, ecology, systematics and in biodiversity-related applied fields such as environmental management and natural product research. Advances in DNA sequencing technologies make genome sequencing feasible for many non-genetic model species. However, genome sequencing today relies on large quantities of high quality, high molecular weight (HMW) DNA which is mostly obtained from fresh tissues. This is problematic for biodiversity genomics of Metazoa as most species are small and yield minute amounts of DNA. Furthermore, briging living specimens to the lab bench not realistic for the majority of species.Here we overcome those difficulties by sequencing two species of springtails (Collembola) from single specimens preserved in ethanol. We used a newly developed, genome-wide amplification-based protocol to generate PacBio libraries for HiFi long-read sequencing.The assembled genomes were highly continuous. They can be considered complete as we recovered over 95% of BUSCOs. Genome-wide amplification does not seem to bias genome recovery. Presence of almost complete copies of the mitochondrial genome in the nuclear genome were pitfalls for automatic assemblers. The genomes fit well into an existing phylogeny of springtails. A neotype is designated for one of the species, blending genome sequencing and creation of taxonomic references.Our study shows that it is possible to obtain high quality genomes from small, field-preserved sub-millimeter metazoans, thus making their vast diversity accessible to the fields of genomics.
- Published
- 2020
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41. SambaR: an R package for fast, easy and reproducible population-genetic analyses of biallelic SNP datasets
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A. Rus Hoelzel, Menno J. de Jong, Joost F. de Jong, and Axel Janke
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education.field_of_study ,Computer science ,business.industry ,Population ,Locus (genetics) ,Single-nucleotide polymorphism ,Filter (higher-order function) ,computer.software_genre ,R package ,Software ,SNP ,Data mining ,business ,education ,computer ,Selection (genetic algorithm) - Abstract
BackgroundSNP datasets can be used to infer a wealth of information about natural populations, including information about their structure, genetic diversity, and the presence of loci under selection. However, SNP data analysis can be a time-consuming and challenging process, not in the least because at present many different software packages are needed to execute and depict the wide variety of mainstream population-genetic analyses. Here we present SambaR, an integrative and user-friendly R package which automates and simplifies quality control and population-genetic analyses of biallelic SNP datasets. SambaR allows users to perform mainstream population-genetic analyses and to generate a wide variety of ready to publish graphs with a minimum number of commands (less than ten). These wrapper commands call functions of existing packages (including adegenet, ape, LEA, poppr, pcadapt and StAMPP) as well as new tools uniquely implemented in SambaR.ResultsWe tested SambaR on online available SNP datasets and found that SambaR can process datasets of millions of SNPs and hundreds of individuals within hours, given sufficient computing power. Newly developed tools implemented in SambaR facilitate optimization of filter settings, objective interpretation of ordination analyses, enhance comparability of diversity estimates from reduced representation library SNP datasets, and generate reduced SNP panels and structure-like plots with Bayesian population assignment probabilities.ConclusionSambaR facilitates rapid population genetic analyses on biallelic SNP datasets by removing three major time sinks: file handling, software learning, and data plotting. In addition, SambaR provides a convenient platform for SNP data storage and management, as well as several new utilities, including guidance in setting appropriate data filters.Availability and implementationThe SambaR source script, manual and example datasets are distributed through GitHub:https://github.com/mennodejong1986/SambaR
- Published
- 2020
- Full Text
- View/download PDF
42. Whole-genome analysis of giraffe supports four distinct species
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Klaus-Peter Koepfli, Julian Fennessy, Axel Janke, Pavel Dobrynin, Sven Winter, Vikas Kumar, Raphael T. F. Coimbra, and Rebecca M. Gooley
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0301 basic medicine ,Gene Flow ,Male ,Population ,Biodiversity ,Genomics ,Giraffes ,Biology ,Subspecies ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Critically endangered ,0302 clinical medicine ,Species Specificity ,Animals ,Giraffa ,education ,Phylogeny ,education.field_of_study ,Genome ,biology.organism_classification ,030104 developmental biology ,Taxon ,Evolutionary biology ,Taxonomy (biology) ,General Agricultural and Biological Sciences ,030217 neurology & neurosurgery - Abstract
Summary Species is the fundamental taxonomic unit in biology and its delimitation has implications for conservation. In giraffe (Giraffa spp.), multiple taxonomic classifications have been proposed since the early 1900s. 1 However, one species with nine subspecies has been generally accepted, 2 likely due to limited in-depth assessments, subspecies hybridizing in captivity, 3 , 4 and anecdotal reports of hybrids in the wild. 5 Giraffe taxonomy received new attention after population genetic studies using traditional genetic markers suggested at least four species. 6 , 7 This view has been met with controversy, 8 setting the stage for debate. 9 , 10 Genomics is significantly enhancing our understanding of biodiversity and speciation relative to traditional genetic approaches and thus has important implications for species delineation and conservation. 11 We present a high-quality de novo genome assembly of the critically endangered Kordofan giraffe (G. camelopardalis antiquorum) 12 and a comprehensive whole-genome analysis of 50 giraffe representing all traditionally recognized subspecies. Population structure and phylogenomic analyses support four separately evolving giraffe lineages, which diverged 230–370 ka ago. These lineages underwent distinct demographic histories and show different levels of heterozygosity and inbreeding. Our results strengthen previous findings of limited gene flow and admixture among putative giraffe species 6 , 7 , 9 and establish a genomic foundation for recognizing four species and seven subspecies, the latter of which should be considered as evolutionary significant units. Achieving a consensus over the number of species and subspecies in giraffe is essential for adequately assessing their threat level and will improve conservation efforts for these iconic taxa.
- Published
- 2020
43. Species assignment and conservation genetics of giraffe in the Republic of Malawi
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Julian Fennessy, Anna Bronec, Axel Janke, Raphael T. F. Coimbra, Amanda L. Salb, Sven Winter, and Craig Hay
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0106 biological sciences ,0301 basic medicine ,Conservation genetics ,Genetic diversity ,education.field_of_study ,biology ,Population ,Biodiversity ,Zoology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,03 medical and health sciences ,030104 developmental biology ,Masai giraffe ,Genetics ,Inbreeding depression ,Giraffa ,education ,Inbreeding ,Ecology, Evolution, Behavior and Systematics - Abstract
Historically, giraffe have been translocated across Africa to supplement extant populations, reintroduce extinct populations or to establish new populations, often for conservation and tourism. Such faunal relocations were often carried out disregarding taxonomic affiliation. Today, the small giraffe populations in the Republic of Malawi are assumed to consist of South African giraffe (Giraffa giraffa giraffa), which have likely descended from five individuals translocated from Imire Game Park (Zimbabwe) to Nyala Game Park (Malawi) in 1993. However, during the last 25 years, unknown additional translocations, migrations or unrecognized local populations of potential Masai giraffe (Giraffa tippelskirchi) in Malawi may have resulted in introgressive hybridization. Thus, the current taxonomic affiliation for Malawi’s giraffe is uncertain, calling for a genetic assessment to implement further management. We analyzed mitochondrial sequences and nuclear introns for 14 individuals, representing approximately half of the known Malawian population, to genetically determine the (sub)species of giraffe that occur in the Republic of Malawi by comparison with a comprehensive Giraffa dataset. Additionally, we genotyped individuals at ten microsatellite loci to determine the level of inbreeding and potential introgression. All data identify individuals unambiguously as South African giraffe, although two individuals shared a single nuclear allele with Masai giraffe. The low microsatellite genetic variability suggests high inbreeding in the current population. Thus, supplementing Malawi’s giraffe populations with G. g. giraffa will prevent further loss of their genetic diversity and avoid inbreeding depression.
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- 2019
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44. Education in the genomics era: Generating high-quality genome assemblies in university courses
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Sven Winter, Deepak K. Gupta, Fritjof Lammers, Magnus Wolf, Maria Nilsson, Jordi De Raad, Tilman Schell, Raphael T. F. Coimbra, Malte Petersen, Axel Janke, and Stefan Prost
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Universities ,Computer science ,media_common.quotation_subject ,AcademicSubjects/SCI02254 ,education ,Sequence assembly ,MinION ,Health Informatics ,Genomics ,Genome ,DNA sequencing ,03 medical and health sciences ,0302 clinical medicine ,Server ,ComputingMilieux_COMPUTERSANDEDUCATION ,Genetics ,Humans ,Quality (business) ,030304 developmental biology ,media_common ,Oxford Nanopore Technologies ,0303 health sciences ,university education ,Medical research ,Data science ,teaching ,Computer Science Applications ,ComputingMethodologies_PATTERNRECOGNITION ,Genetic Techniques ,Minion ,Commentary ,genome assembly ,AcademicSubjects/SCI00960 ,030217 neurology & neurosurgery - Abstract
Recent advances in genome sequencing technologies have simplified the generation of genome data and reduced the costs for genome assemblies, even for complex genomes like those of vertebrates. More practically oriented genomic courses can prepare university students for the increasing importance of genomic data used in biological and medical research. Low-cost third-generation sequencing technology, along with publicly available data, can be used to teach students how to process genomic data, assemble full chromosome-level genomes, and publish the results in peer-reviewed journals, or preprint servers. Here we outline experiences gained from 2 master's-level courses and discuss practical considerations for teaching hands-on genome assembly courses.
- Published
- 2020
45. Matrilineal population structure and distribution of the Angolan giraffe in the Namib desert and beyond
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Sven Winter, Julian Fennessy, Stephanie Fennessy, and Axel Janke
- Subjects
0106 biological sciences ,0301 basic medicine ,Genetic diversity ,biology ,Cytochrome b ,National park ,Zoology ,Subspecies ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,03 medical and health sciences ,030104 developmental biology ,Geography ,Geographical distance ,Genetics ,Philopatry ,Giraffa ,Clade ,Ecology, Evolution, Behavior and Systematics - Abstract
The distribution maps of giraffe (Giraffa) subspecies in southern Africa are based on historical assumptions, yet some populations have likely been misidentified, hindering effective conservation efforts. Particularly, the populations in Zimbabwe are poorly studied, and translocations, such as the 1991 movement of giraffe from Namibia's Etosha National Park to mitigate the human-induced decline of Namibia's desert-dwelling giraffe in the lower Hoanib and Hoarusib Rivers, was concluded without consideration of genotype. Mitochondrial DNA sequence analyses from cytochrome b and control region revealed that instead of the South African giraffe subspecies (G. giraffa giraffa), the Angolan giraffe (G. g. angolensis) occurs in southern Zimbabwe's Bubye Valley Conservancy. Furthermore, Namibia's desert-dwelling giraffe and those from Etosha National Park form distinct matrilineal lineages within the Angolan giraffe subspecies clade. Thus, despite the translocation and proximity of the Etosha National Park, the Etosha giraffe genotype has not spread amongst the desert-dwelling giraffe. Use of mutation rate estimates indicates that there has been no matrilineal exchange between Etosha and the desert-dwelling giraffe for ca. 40,000 years. While philopatry could produce distinct mitochondrial lineages, the short geographical distance and long time involved, makes it more likely that the Etosha giraffe cannot successfully compete with a putatively better adapted desert-dwelling giraffe. The analyses also show that the distribution of the Angolan giraffe extends further eastwards than expected. These findings provide important implications for giraffe conservation, and translocation in particular, which may not always be an effective means of improving genetic diversity.
- Published
- 2018
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46. Conservation Genomics of Two Threatened Subspecies of Northern Giraffe: The West African and the Kordofan Giraffe
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Raphael T. F. Coimbra, Sven Winter, Barbara Mitchell, Julian Fennessy, and Axel Janke
- Subjects
Genome ,Geography ,Genetics ,Animals ,Genomics ,Giraffes ,Phylogeny ,Genetics (clinical) - Abstract
Three of the four species of giraffe are threatened, particularly the northern giraffe (Giraffa camelopardalis), which collectively have the smallest known wild population estimates. Among the three subspecies of the northern giraffe, the West African giraffe (Giraffa camelopardalis peralta) had declined to 49 individuals by 1996 and only recovered due to conservation efforts undertaken in the past 25 years, while the Kordofan giraffe (Giraffa camelopardalis antiquorum) remains at
- Published
- 2022
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47. Detection of SARS-CoV-2 in raw and treated wastewater in Germany – Suitability for COVID-19 surveillance and potential transmission risks
- Author
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Volker Linnemann, Carola Greve, Henner Hollert, Sandra Ciesek, Axel Janke, Sabrina Schiwy, Sandra Westhaus, Frank Andreas Weber, Markus Brinkmann, Thomas Wintgens, and Marek Widera
- Subjects
Environmental Engineering ,010504 meteorology & atmospheric sciences ,viruses ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Pneumonia, Viral ,Wastewater treatment ,Wastewater ,010501 environmental sciences ,Biology ,medicine.disease_cause ,01 natural sciences ,Article ,Virus ,law.invention ,Betacoronavirus ,law ,Germany ,medicine ,Humans ,Environmental Chemistry ,Cities ,Pandemics ,Waste Management and Disposal ,Polymerase chain reaction ,0105 earth and related environmental sciences ,Coronavirus ,Infectivity ,SARS-CoV-2 replication in vitro ,SARS-CoV-2 ,business.industry ,COVID-19 ,Wastewater-based epidemiology (WBE) ,Pollution ,Biotechnology ,Transmission (mechanics) ,Sewage treatment ,Coronavirus Infections ,business - Abstract
Wastewater-based monitoring of the spread of the new SARS-CoV-2 virus, also referred to as wastewater-based epidemiology (WBE), has been suggested as a tool to support epidemiology. An extensive sampling campaign, including nine municipal wastewater treatment plants, has been conducted in different cities of the Federal State of North Rhine-Westphalia (Germany) on the same day in April 2020, close to the first peak of the corona crisis. Samples were processed and analysed for a set of SARS-CoV-2-specific genes, as well as pan-genotypic gene sequences also covering other coronavirus types, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Additionally, a comprehensive set of chemical reference parameters and bioindicators was analysed to characterize the wastewater quality and composition. Results of the RT-qPCR based gene analysis indicate the presence of SARS-CoV-2 genetic traces in different raw wastewaters. Furthermore, selected samples have been sequenced using Sanger technology to confirm the specificity of the RT-qPCR and the origin of the coronavirus. A comparison of the particle-bound and the dissolved portion of SARS-CoV-2 virus genes shows that quantifications must not neglect the solid-phase reservoir. The infectivity of the raw wastewater has also been assessed by viral outgrowth assay with a potential SARS-CoV-2 host cell line in vitro, which were not infected when exposed to the samples. This first evidence suggests that wastewater might be no major route for transmission to humans. Our findings draw attention to the need for further methodological and molecular assay validation for enveloped viruses in wastewater., Graphical abstract Unlabelled Image, Highlights • The first study that reports the detection of SARS-CoV-2 in wastewater in Germany using RT-qPCR. • The presence of SARS-CoV-2 was confirmed by sequencing, but also the risk of false-positive results has been elucidated. • In raw wastewater, 3.0 to 20 gene equivalents/mL was found in raw wastewater. • The replication potential tests were negative for wastewater samples. • Sanger sequencing was required to differentiate the genetic pattern clearly.
- Published
- 2021
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48. Limited introgression supports division of giraffe into four species
- Author
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Julian Fennessy, Sven Winter, and Axel Janke
- Subjects
biology ,conservation ,Introgression ,Population genetics ,Reticulated giraffe ,Subspecies ,biology.organism_classification ,Gene flow ,speciation ,ddc:590 ,Evolutionary biology ,Threatened species ,IUCN Red List ,gene flow ,hybridization ,giraffe ,Giraffa ,Original Research - Abstract
All giraffe (Giraffa) were previously assigned to a single species (G. camelopardalis) and nine subspecies. However, multi-locus analyses of all subspecies have shown that there are four genetically distinct clades and suggest four giraffe species. This conclusion might not be fully accepted due to limited data and lack of explicit gene flow analyses. Here we present an extended study based on 21 independent nuclear loci from 137 individuals. Explicit gene flow analyses identify less than one migrant per generation, including between the closely related northern and reticulated giraffe. Thus, gene flow analyses and population genetics of the extended dataset confirm four genetically distinct giraffe clades and support four independent giraffe species. The new findings call for a revision of the IUCN classification of giraffe taxonomy. Three of the four species are threatened with extinction, mostly occurring in politically unstable regions, and as such, require the highest conservation support possible.
- Published
- 2018
49. Implementing and testing the multispecies coalescent model: A valuable paradigm for phylogenomics
- Author
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Scott V. Edwards, Zhenxiang Xi, Bojian Zhong, Liang Liu, Adam D. Leaché, Emily Moriarty Lemmon, Travis C. Glenn, John E. McCormack, Axel Janke, Charles C. Davis, Brant C. Faircloth, Shaoyuan Wu, and Alan R. Lemmon
- Subjects
0301 basic medicine ,Sorting algorithm ,Theoretical computer science ,Genetic Speciation ,Concatenation ,Variation (game tree) ,Biology ,Coalescent theory ,Evolution, Molecular ,03 medical and health sciences ,Magnoliopsida ,Phylogenomics ,Statistics ,Genetics ,Animals ,Computer Simulation ,Special case ,Molecular Biology ,Phylogeny ,Ecology, Evolution, Behavior and Systematics ,Mammals ,Recombination, Genetic ,Models, Genetic ,Genomics ,Tree (data structure) ,030104 developmental biology ,Neutrality - Abstract
In recent articles published in Molecular Phylogenetics and Evolution, Mark Springer and John Gatesy (S&G) present numerous criticisms of recent implementations and testing of the multispecies coalescent (MSC) model in phylogenomics, popularly known as "species tree" methods. After pointing out errors in alignments and gene tree rooting in recent phylogenomic data sets, particularly in Song et al. (2012) on mammals and Xi et al. (2014) on plants, they suggest that these errors seriously compromise the conclusions of these studies. Additionally, S&G enumerate numerous perceived violated assumptions and deficiencies in the application of the MSC model in phylogenomics, such as its assumption of neutrality and in particular the use of transcriptomes, which are deemed inappropriate for the MSC because the constituent exons often subtend large regions of chromosomes within which recombination is substantial. We acknowledge these previously reported errors in recent phylogenomic data sets, but disapprove of S&G's excessively combative and taunting tone. We show that these errors, as well as two nucleotide sorting methods used in the analysis of Amborella, have little impact on the conclusions of those papers. Moreover, several concepts introduced by S&G and an appeal to "first principles" of phylogenetics in an attempt to discredit MSC models are invalid and reveal numerous misunderstandings of the MSC. Contrary to the claims of S&G we show that recent computer simulations used to test the robustness of MSC models are not circular and do not unfairly favor MSC models over concatenation. In fact, although both concatenation and MSC models clearly perform well in regions of tree space with long branches and little incomplete lineage sorting (ILS), simulations reveal the erratic behavior of concatenation when subjected to data subsampling and its tendency to produce spuriously confident yet conflicting results in regions of parameter space where MSC models still perform well. S&G's claims that MSC models explain little or none (0-15%) of the observed gene tree heterogeneity observed in a mammal data set and that MSC models assume ILS as the only source of gene tree variation are flawed. Overall many of their criticisms of MSC models are invalidated when concatenation is appropriately viewed as a special case of the MSC, which in turn is a special case of emerging network models in phylogenomics. We reiterate that there is enormous promise and value in recent implementations and tests of the MSC and look forward to its increased use and refinement in phylogenomics.
- Published
- 2016
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50. Y chromosome haplotype distribution of brown bears (Ursus arctos ) in Northern Europe provides insight into population history and recovery
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Konstantin Tirronen, Piotr Danilov, Ilpo Kojola, Eugene A. Poroshin, Hans Geir Eiken, Julia Schregel, Frank Hailer, Alexander M. Rykov, Axel Janke, Snorre B. Hagen, Jouni Aspi, Jon E. Swenson, and Finn Audun Grøndahl
- Subjects
Gene Flow ,Population ,Zoology ,Biology ,Polymorphism, Single Nucleotide ,Haplogroup ,Russia ,Gene flow ,Y Chromosome ,Genetics ,Animals ,Y-STR ,Ursus ,education ,Y-SNP ,Finland ,Ecology, Evolution, Behavior and Systematics ,Sweden ,education.field_of_study ,Norway ,Population size ,Haplotype ,biology.organism_classification ,Genetics, Population ,Haplotypes ,Animal Distribution ,Ursidae - Abstract
High-resolution, male-inherited Y-chromosomal markers are a useful tool for population genetic analyses of wildlife species, but to date have only been applied in this context to relatively few species besides humans. Using nine Y-chromosomal STRs and three Y-chromosomal single nucleotide polymorphism markers (Y-SNPs), we studied whether male gene flow was important for the recent recovery of the brown bear (Ursus arctos) in Northern Europe, where the species declined dramatically in numbers and geographical distribution during the last centuries but is expanding now. We found 36 haplotypes in 443 male extant brown bears from Sweden, Norway, Finland and northwestern Russia. In 14 individuals from southern Norway from 1780 to 1920, we found two Y chromosome haplotypes present in the extant population as well as four Y chromosome haplotypes not present among the modern samples. Our results suggested major differences in genetic connectivity, diversity and structure between the eastern and the western populations in Northern Europe. In the west, our results indicated that the recovered population originated from only four male lineages, displaying pronounced spatial structuring suggestive of large-scale population size increase under limited male gene flow within the western subpopulation. In the east, we found a contrasting pattern, with high haplotype diversity and admixture. This first population genetic analysis of male brown bears shows conclusively that male gene flow was not the main force of population recovery.
- Published
- 2015
- Full Text
- View/download PDF
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