Publications by authors named "Axel Janke"

Sex chromosomes differ in their inheritance properties from autosomes and hence may encode complementary information about past demographic events. We compiled and analyzed a range-wide resequencing data set of the red deer (Cervus elaphus), one of the few Eurasian herbivores of the Late Pleistocene megafauna still found throughout much of its historic range. Our analyses of 144 whole genomes reveal striking discrepancies between the population clusters suggested by autosomal and X-chromosomal data.

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The blue whale is an endangered and globally distributed species of baleen whale with multiple described subspecies, including the morphologically and genetically distinct pygmy blue whale. North Atlantic and North Pacific populations, however, are currently regarded as a single subspecies despite being separated by continental land masses and acoustic call differences. To determine the degree of isolation among the Northern Hemisphere populations, 14 North Pacific and 6 Western Australian blue whale nuclear and mitochondrial genomes were sequenced and analysed together with 11 publicly available North Atlantic blue whale genomes.

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Article Synopsis
  • The Baikal seal, a freshwater seal unique to Lake Baikal, has a long history of being landlocked and is classified as a species of least concern due to its stable population despite its limited habitat.
  • Recent research has expanded on genetic studies by sequencing the genomes of six Baikal seals alongside other seal species, enhancing our understanding of their evolutionary relationships.
  • Findings indicate that the genetic diversity of the Baikal seal is comparable to that of other seals, prompting calls for further research on genomic diversity across its range.
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The time required for genome sequencing and 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 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.

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Studying wildlife taxonomic diversity and identifying distinct populations has traditionally been largely based on morphology and geographic origin. More recently, this method has been supplemented by genetic data from the mitochondrial genome. However, this is limited as only maternally inherited and may not reflect the true nature of a population's genetics.

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The snake pipefish, (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 . The final assembly spans 1.

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Article Synopsis
  • Snakeflies, an ancient and small order of insects, have maintained their unique appearance for over 300 million years, yet they lack public interest and sufficient molecular research.
  • Researchers have published the first complete genome of the snakefly order, showing a total length of 669 Mbp and high-quality assembly metrics.
  • The study reveals significant genetic complexities and potential evolutionary events since the dinosaurs' extinction, providing a valuable resource for future research in understanding snakefly evolution and genetics.
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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.

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Half a century after its foundation, the neutral theory of molecular evolution continues to attract controversy. The debate has been hampered by the coexistence of different interpretations of the core proposition of the neutral theory, the 'neutral mutation-random drift' hypothesis. In this review, we trace the origins of these ambiguities and suggest potential solutions.

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Understanding speciation is one of the cornerstones of biological diversity research. Currently, speciation is often understood as a continuous process of divergence that continues until genetic or other incompatibilities minimize or prevent interbreeding. The Palearctic snake genus Natrix is an ideal group to study speciation, as it comprises taxa representing distinct stages of the speciation process, ranging from widely interbreeding parapatric taxa through parapatric species with very limited gene flow in narrow hybrid zones to widely sympatric species.

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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.

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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.

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Population-genomic studies can shed new light on the effect of past demographic processes on contemporary population structure. We reassessed phylogeographical patterns of a classic model species of postglacial recolonisation, the brown bear (Ursus arctos), using a range-wide resequencing dataset of 128 nuclear genomes. In sharp contrast to the erratic geographical distribution of mtDNA and Y-chromosomal haplotypes, autosomal and X-chromosomal multi-locus datasets indicate that brown bear population structure is largely explained by recent population connectivity.

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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).

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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.

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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).

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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.

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Vampire bats are the only mammals that feed exclusively on blood. To uncover genomic changes associated with this dietary adaptation, we generated a haplotype-resolved genome of the common vampire bat and screened 27 bat species for genes that were specifically lost in the vampire bat lineage. We found previously unknown gene losses that relate to reduced insulin secretion ( and ), limited glycogen stores (), and a unique gastric physiology ().

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Three of the four species of giraffe are threatened, particularly the northern giraffe (), which collectively have the smallest known wild population estimates. Among the three subspecies of the northern giraffe, the West African giraffe () had declined to 49 individuals by 1996 and only recovered due to conservation efforts undertaken in the past 25 years, while the Kordofan giraffe () remains at <2300 individuals distributed in small, isolated populations over a large geographical range in Central Africa. These combined factors could lead to genetically depauperated populations.

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Like many carnivore species, European wildcats () 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.

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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.

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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.

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Article Synopsis
  • A new genus and species of mud snake, Myanophis thanlyinensis, has been identified near East Yangon University in Myanmar, distinguished by unique physical traits such as smooth dorsal scales and specific scale counts.
  • This snake’s lineage, determined through genetic analysis, places it close to the genera Myrrophis and Gyiophis, with notable differences like its bilobed hemipenis and variations in ventral and subcaudal scales.
  • The study features an identification key for homalopsid species in Myanmar and introduces an advanced genomic sequencing approach that offers a comprehensive characterization of the new species’ genetic variation.
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