1
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Haider M, Schilling MP, Moest MH, Steiner FM, Schlick‐Steiner BC, Arthofer W. Evolutionary history of an Alpine Archaeognath ( Machilis pallida): Insights from different variant. Ecol Evol 2023; 13:e10227. [PMID: 37404697 PMCID: PMC10316371 DOI: 10.1002/ece3.10227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 05/31/2023] [Accepted: 06/09/2023] [Indexed: 07/06/2023] Open
Abstract
Reconstruction of species histories is a central aspect of evolutionary biology. Patterns of genetic variation within and among populations can be leveraged to elucidate evolutionary processes and demographic histories. However, interpreting genetic signatures and unraveling the contributing processes can be challenging, in particular for non-model organisms with complex reproductive modes and genome organization. One way forward is the combined consideration of patterns revealed by different molecular markers (nuclear vs. mitochondrial) and types of variants (common vs. rare) that differ in their age, mode, and rate of evolution. Here, we applied this approach to RNAseq data generated for Machilis pallida (Archaeognatha), an Alpine jumping bristletail considered parthenogenetic and triploid. We generated de novo transcriptome and mitochondrial assemblies to obtain high-density data to investigate patterns of mitochondrial and common and rare nuclear variation in 17 M. pallida individuals sampled from all known populations. We find that the different variant types capture distinct aspects of the evolutionary history and discuss the observed patterns in the context of parthenogenesis, polyploidy, and survival during glaciation. This study highlights the potential of different variant types to gain insights into evolutionary scenarios even from challenging but often available data and the suitability of M. pallida and the genus Machilis as a study system for the evolution of sexual strategies and polyploidization during environmental change. We also emphasize the need for further research which will be stimulated and facilitated by these newly generated resources and insights.
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Affiliation(s)
- Marlene Haider
- Department of Ecology, Molecular Ecology GroupUniversity of InnsbruckInnsbruckAustria
| | - Martin P. Schilling
- Department of Ecology, Molecular Ecology GroupUniversity of InnsbruckInnsbruckAustria
| | - Markus H. Moest
- Department of Ecology, Molecular Ecology GroupUniversity of InnsbruckInnsbruckAustria
| | - Florian M. Steiner
- Department of Ecology, Molecular Ecology GroupUniversity of InnsbruckInnsbruckAustria
| | | | - Wolfgang Arthofer
- Department of Ecology, Molecular Ecology GroupUniversity of InnsbruckInnsbruckAustria
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2
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Hagberg L, Celemín E, Irisarri I, Hawlitschek O, Bella JL, Mott T, Pereira RJ. Extensive introgression at late stages of species formation: Insights from grasshopper hybrid zones. Mol Ecol 2022; 31:2384-2399. [PMID: 35191134 DOI: 10.1111/mec.16406] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 02/02/2022] [Accepted: 02/14/2022] [Indexed: 11/30/2022]
Abstract
The process of species formation is characterised by the accumulation of multiple reproductive barriers. The evolution of hybrid male sterility, or Haldane's rule, typically characterises later stages of species formation, when reproductive isolation is strongest. Yet, understanding how quickly reproductive barriers evolve and their consequences for maintaining genetic boundaries between emerging species remains a challenging task because it requires studying taxa that hybridise in nature. Here, we address these questions using the meadow grasshopper Pseudochorthippus parallelus, where populations that show multiple reproductive barriers, including hybrid male sterility, hybridise in two natural hybrid zones. Using mitochondrial data, we infer that such populations have diverged some 100,000 years ago, at the beginning of the last glacial cycle in Europe. Nuclear data shows that contractions at multiple glacial refugia, and post-glacial expansions have facilitated genetic differentiation between lineages that today interact in hybrid zones. We find extensive introgression throughout the sampled species range, irrespective of current strength of reproductive isolation. Populations exhibiting hybrid male sterility in two hybrid zones show repeatable patterns of genomic differentiation, consistent with shared genomic constraints affecting ancestral divergence or with the role of those regions in reproductive isolation. Together, our results suggest that reproductive barriers that characterise late stages of species formation can evolve relatively quickly, particularly when associated with strong demographic changes. Moreover, we show that such barriers persist in the face of extensive gene flow, allowing future studies to identify associated genomic regions.
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Affiliation(s)
- Linda Hagberg
- Division of Evolutionary Biology, Faculty of Biology II, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152, Planegg-Martinsried, Germany
| | - Enrique Celemín
- Division of Evolutionary Biology, Faculty of Biology II, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152, Planegg-Martinsried, Germany.,Unit of Evolutionary Biology/Systematic Zoology, Institute of Biochemistry and Biology, Universität Potsdam, Karl-Liebknecht-Strasse 24-25, 14476, Potsdam, Germany
| | - Iker Irisarri
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077, Göttingen, Germany.,Campus Institute Data Science (CIDAS), Göttingen, Germany
| | - Oliver Hawlitschek
- Leibniz Institute for the Analysis of Biodiversity Change, Zoological Museum, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany.,Zoologische Staatssammlung (SNSB-ZSM), Münchhausenstr. 21, 81247, Munich, Germany
| | - José L Bella
- Departamento de Biología (Genética), Facultad de Ciencias, Universidad Autónoma de Madrid, 28049, Madrid, Spain.,Centro de Investigación en Biodiversidad y Cambio Global (CIBC-UAM), Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Tamí Mott
- Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Alagoas, 57072-900, Maceió, Alagoas, Brazil
| | - Ricardo J Pereira
- Division of Evolutionary Biology, Faculty of Biology II, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152, Planegg-Martinsried, Germany
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3
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Kirschner P, Arthofer W, Pfeifenberger S, Záveská E, Schönswetter P, Steiner FM, Schlick-Steiner BC. Performance comparison of two reduced-representation based genome-wide marker-discovery strategies in a multi-taxon phylogeographic framework. Sci Rep 2021; 11:3978. [PMID: 33597550 PMCID: PMC7889850 DOI: 10.1038/s41598-020-79778-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 12/09/2020] [Indexed: 01/31/2023] Open
Abstract
Multi-locus genetic data are pivotal in phylogenetics. Today, high-throughput sequencing (HTS) allows scientists to generate an unprecedented amount of such data from any organism. However, HTS is resource intense and may not be accessible to wide parts of the scientific community. In phylogeography, the use of HTS has concentrated on a few taxonomic groups, and the amount of data used to resolve a phylogeographic pattern often seems arbitrary. We explore the performance of two genetic marker sampling strategies and the effect of marker quantity in a comparative phylogeographic framework focusing on six species (arthropods and plants). The same analyses were applied to data inferred from amplified fragment length polymorphism fingerprinting (AFLP), a cheap, non-HTS based technique that is able to straightforwardly produce several hundred markers, and from restriction site associated DNA sequencing (RADseq), a more expensive, HTS-based technique that produces thousands of single nucleotide polymorphisms. We show that in four of six study species, AFLP leads to results comparable with those of RADseq. While we do not aim to contest the advantages of HTS techniques, we also show that AFLP is a robust technique to delimit evolutionary entities in both plants and animals. The demonstrated similarity of results from the two techniques also strengthens biological conclusions that were based on AFLP data in the past, an important finding given the wide utilization of AFLP over the last decades. We emphasize that whenever the delimitation of evolutionary entities is the central goal, as it is in many fields of biodiversity research, AFLP is still an adequate technique.
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Affiliation(s)
- Philipp Kirschner
- grid.5771.40000 0001 2151 8122Department of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria ,grid.5771.40000 0001 2151 8122Department of Botany, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria
| | - Wolfgang Arthofer
- grid.5771.40000 0001 2151 8122Department of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Stefanie Pfeifenberger
- grid.5771.40000 0001 2151 8122Department of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Eliška Záveská
- grid.5771.40000 0001 2151 8122Department of Botany, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria
| | - Peter Schönswetter
- grid.5771.40000 0001 2151 8122Department of Botany, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria
| | | | - Florian M. Steiner
- grid.5771.40000 0001 2151 8122Department of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Birgit C. Schlick-Steiner
- grid.5771.40000 0001 2151 8122Department of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
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4
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Pan D, Hülber K, Willner W, Schneeweiss GM. An explicit test of Pleistocene survival in peripheral versus nunatak refugia in two high mountain plant species. Mol Ecol 2019; 29:172-183. [PMID: 31765501 PMCID: PMC7003806 DOI: 10.1111/mec.15316] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 11/20/2019] [Accepted: 11/22/2019] [Indexed: 01/15/2023]
Abstract
Pleistocene climate fluctuations had profound influence on the biogeographical history of many biota. As large areas in high mountain ranges were covered by glaciers, biota were forced either to peripheral refugia (and possibly beyond to lowland refugia) or to interior refugia (nunataks). However, nunatak survival remains controversial as it relies solely on correlative genetic evidence. Here, we test hypotheses of glacial survival using two high alpine plant species (the insect‐pollinated Pedicularis asplenifolia and wind‐pollinated Carex fuliginosa) in the European Alps. Employing the iDDC (integrative Distributional, Demographic and Coalescent) approach, which couples species distribution modelling, spatial and temporal demographic simulation and Approximate Bayesian Computation, we explicitly test three hypotheses of glacial survival: (a) peripheral survival only, (b) nunatak survival only and (c) peripheral plus nunatak survival. In P. asplenifolia the peripheral plus nunatak survival hypothesis was supported by Bayes factors (BF> 100), whereas in C. fuliginosa the peripheral survival only hypothesis, although best supported, could not be unambiguously distinguished from the peripheral plus nunatak survival hypothesis (BF = 5.58). These results are consistent with current habitat preferences (P. asplenifolia extends to higher elevations) and the potential for genetic swamping (i.e., replacement of local genotypes via hybridization with immigrating genotypes [expected to be higher in the wind‐pollinated C. fuliginosa]). Although the persistence of plants on nunataks during glacial periods has been debated and studied over decades, this is one of the first studies to explicitly test the hypothesis instead of solely using correlative evidence.
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Affiliation(s)
- Da Pan
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Karl Hülber
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Wolfgang Willner
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Gerald M Schneeweiss
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
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5
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Schönswetter P, Schneeweiss GM. Is the incidence of survival in interior Pleistocene refugia (nunataks) underestimated? Phylogeography of the high mountain plant Androsace alpina (Primulaceae) in the European Alps revisited. Ecol Evol 2019; 9:4078-4086. [PMID: 31015989 PMCID: PMC6468090 DOI: 10.1002/ece3.5037] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 02/11/2019] [Accepted: 02/18/2019] [Indexed: 01/17/2023] Open
Abstract
Temperate mountain ranges such as the European Alps have been strongly affected by the Pleistocene glaciations. Glacial advances forced biota into refugia, which were situated either at the periphery of mountain ranges or in their interior. Whereas in the Alps peripheral refugia have been repeatedly and congruently identified, support for the latter scenario, termed "nunatak hypothesis," is still limited and no general pattern is recognizable yet. Here, we test the hypothesis of nunatak survival for species growing in the high alpine to subnival zones on siliceous substrate using the cushion plant Androsace alpina (Primulaceae), endemic to the European Alps, as our model species. To this end, we analyzed AFLP and plastid DNA sequence data obtained from a dense and range-wide sampling. Both AFLPs and plastid sequence data identified the southwestern-most population as the most divergent one. AFLP data did not allow for discrimination of interior and peripheral populations, but rather identified two to three longitudinally separated major gene pools. In contrast, in the eastern half of the Alps several plastid haplotypes of regional or local distribution in interior ranges-the Alpine periphery mostly harbored a widespread haplotype-were indicative for the presence of interior refugia. Together with evidence from other Alpine plant species, this study shows that in the eastern Alps silicicolous species of open habitats in the alpine and subnival zone survived, also or exclusively so, in interior refugia. As the corresponding genetic structure may be lost in mostly nuclear-derived, rapidly homogenizing marker systems such as AFLPs or RAD sequencing tags, markers not prone to homogenization, as is the case for plastid sequences (Sanger-sequenced or extracted from an NGS data set) will continue to be important for detecting older, biogeographically relevant patterns.
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6
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Abstract
Current knowledge of the Canadian bristletail (Archaeognatha) fauna is summarized and compared with Tomlin's 1979 chapter on the group in Canada and Its Insect Fauna. Since that time the number of species known from Canada has increased from three to eight. While much work remains to be done to document an estimated eight additional species from Canada, this can be accomplished using an integrated approach.
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Affiliation(s)
- Matthew L. Bowser
- U.S. Fish & Wildlife Service, Kenai National Wildlife Refuge, Soldotna, Alaska, USAU.S. Fish & Wildlife ServiceSoldotnaUnited States of America
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7
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Steiner FM, Csősz S, Markó B, Gamisch A, Rinnhofer L, Folterbauer C, Hammerle S, Stauffer C, Arthofer W, Schlick-Steiner BC. Turning one into five: Integrative taxonomy uncovers complex evolution of cryptic species in the harvester ant Messor “structor”. Mol Phylogenet Evol 2018; 127:387-404. [DOI: 10.1016/j.ympev.2018.04.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 03/02/2018] [Accepted: 04/04/2018] [Indexed: 11/25/2022]
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8
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Life-History Responses to the Altitudinal Gradient. HIGH MOUNTAIN CONSERVATION IN A CHANGING WORLD 2017. [DOI: 10.1007/978-3-319-55982-7_11] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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9
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Vershinina AO, Kuznetsova VG. Parthenogenesis in Hexapoda: Entognatha and non-holometabolous insects. J ZOOL SYST EVOL RES 2016. [DOI: 10.1111/jzs.12141] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Alisa O. Vershinina
- Department of Karyosystematics; Zoological Institute of Russian Academy of Sciences; St. Petersburg Russia
- Department of Ecology & Evolutionary Biology; University of California Santa Cruz; Santa Cruz CA USA
| | - Valentina G. Kuznetsova
- Department of Karyosystematics; Zoological Institute of Russian Academy of Sciences; St. Petersburg Russia
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10
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Wachter GA, Papadopoulou A, Muster C, Arthofer W, Knowles LL, Steiner FM, Schlick-Steiner BC. Glacial refugia, recolonization patterns and diversification forces in Alpine-endemicMegabunusharvestmen. Mol Ecol 2016; 25:2904-19. [DOI: 10.1111/mec.13634] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 03/06/2016] [Accepted: 03/22/2016] [Indexed: 02/06/2023]
Affiliation(s)
- Gregor A. Wachter
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstraße 25 6020 Innsbruck Austria
| | - Anna Papadopoulou
- Department of Ecology and Evolutionary Biology; Museum of Zoology; University of Michigan; Ann Arbor MI 48109-1079 USA
- Department of Integrative Ecology; Estación Biológica de Doñana (CSIC); 41092 Seville Spain
| | - Christoph Muster
- Zoological Institute and Museum; University of Greifswald; Johann-Sebastian-Bach-Straße 11/12 17487 Greifswald Germany
| | - Wolfgang Arthofer
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstraße 25 6020 Innsbruck Austria
| | - L. Lacey Knowles
- Department of Ecology and Evolutionary Biology; Museum of Zoology; University of Michigan; Ann Arbor MI 48109-1079 USA
| | - Florian M. Steiner
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstraße 25 6020 Innsbruck Austria
| | - Birgit C. Schlick-Steiner
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstraße 25 6020 Innsbruck Austria
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11
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Dejaco T, Gassner M, Arthofer W, Schlick-Steiner BC, Steiner FM. Taxonomist's Nightmare … Evolutionist's Delight : An Integrative Approach Resolves Species Limits in Jumping Bristletails Despite Widespread Hybridization and Parthenogenesis. Syst Biol 2016; 65:947-974. [PMID: 26869489 PMCID: PMC5066060 DOI: 10.1093/sysbio/syw003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 10/26/2015] [Accepted: 01/14/2016] [Indexed: 11/13/2022] Open
Abstract
Accurate species delimitation is fundamental to biology. Traditionally, species were delimited based on morphological characters, sometimes leading to taxonomic uncertainty in morphologically conserved taxa. Recently, multiple taxonomically challenging cases have benefited from integrative taxonomy-an approach that highlights congruence among different disciplines and invokes evolutionary explanations for incongruence, acknowledging that different methods can mirror different stages of the speciation continuum. Here, we used a cohesive protocol for integrative taxonomy to revise species limits in 20 nominal species and 4 morphospecies of an ancestrally wingless insect group, the jumping bristletail genus Machilis from the European Eastern Alps. Even though morphologically conserved, several small-scale endemic species have been described from the Eastern Alps based on variation in hypodermal pigmentation patterns-a highly questionable character. As valuable as these endemics are for conservation, they have never been verified by alternative methods. Using traditional morphometrics, mitochondrial DNA, ribosomal DNA, and amplified fragment-length polymorphism markers, we identify six nominal species as taxonomic junior synonyms (Machilis alpicola Janetschek, 1953 syn. n. under M. vagans Wygodzinsky, 1941; M. ladensis Janetschek, 1950 syn. n., M. robusta Wygodzinsky, 1941 syn. n., and M. vicina Wygodzinsky, 1941 syn. n. under M. inermis Wygodzinsky, 1941; M. aleamaculata Wygodzinsky, 1941 syn. n. under M. montana Wygodzinsky, 1941; M. pulchra Janetschek, 1950 syn. n. under M. helleri Verhoeff, 1910) and describe two new species (Machilis cryptoglacialis sp. n. and Machilis albida sp. n.), one uncovered from morphological crypsis and one never sampled before. Building on numerous cases of incongruence among data sources, we further shed light on complex evolutionary histories including hybrid speciation, historical and recent hybridization, and ongoing speciation. We hypothesize that an inherent affinity to hybridization, combined with parallel switches to parthenogenesis and repeated postglacial colonization events may have boosted endemicity in Eastern Alpine Machilis We thus emphasize the importance of integrative taxonomy for rigorous species delimitation and its implication for evolutionary research and conservation in taxonomically challenging taxa.
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Affiliation(s)
- Thomas Dejaco
- Molecular Ecology Group, Institute of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria .,Museum of Nature South Tyrol, Bindergasse 1, 39100 Bozen/Bolzano, Italy
| | - Melitta Gassner
- Molecular Ecology Group, Institute of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Wolfgang Arthofer
- Molecular Ecology Group, Institute of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Birgit C Schlick-Steiner
- Molecular Ecology Group, Institute of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Florian M Steiner
- Molecular Ecology Group, Institute of Ecology, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
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12
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Wachter GA, Muster C, Arthofer W, Raspotnig G, Föttinger P, Komposch C, Steiner FM, Schlick-Steiner BC. Taking the discovery approach in integrative taxonomy: decrypting a complex of narrow-endemic Alpine harvestmen (Opiliones: Phalangiidae: Megabunus). Mol Ecol 2015; 24:863-89. [PMID: 25583278 DOI: 10.1111/mec.13077] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 12/29/2014] [Accepted: 01/07/2015] [Indexed: 02/05/2023]
Abstract
Species delimitation is fundamental for biological studies, yet precise delimitation is not an easy task, and every involved approach has an inherent failure rate. Integrative taxonomy, a method that merges multiple lines of evidence, can profoundly contribute to reliable alpha-taxonomy and shed light on the processes behind speciation. In this study, we explored and validated species limits in a group of closely related Megabunus harvestmen (Eupnoi, Phalangiidae) endemic to the European Alps. Without a priori species hypotheses, we used multiple sources of inference, including mitochondrial and multilocus nuclear DNA, morphometrics and chemistry. The results of these discovery approaches revealed morphological crypsis and multiple new species within two of the five hitherto known species. Based on our analyses, we discussed the most plausible evolutionary scenarios, invoked the most reasonable species hypotheses and validated the new species limits. Building upon the achieved rigour, three new species, Megabunus cryptobergomas Muster and Wachter sp. nov., Megabunus coelodonta Muster and Steiner sp. nov., and Megabunus lentipes Muster and Komposch sp. nov., are formally described. In addition, we provide a dichotomous morphological key to the Megabunus species of the Alps. Our work demonstrates the suitability of integrative, discovery-based approaches in combination with validation approaches to precisely characterize species and enabled us to implement nomenclatural consequences for this genus.
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Affiliation(s)
- Gregor A Wachter
- Molecular Ecology Group, Institute of Ecology, University of Innsbruck, Technikerstraße 25, 6020, Innsbruck, Austria
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13
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Gassner M, Dejaco T, Schönswetter P, Marec F, Arthofer W, Schlick-Steiner BC, Steiner FM. Extensive variation in chromosome number and genome size in sexual and parthenogenetic species of the jumping-bristletail genus Machilis (Archaeognatha). Ecol Evol 2014; 4:4093-105. [PMID: 25505536 PMCID: PMC4242562 DOI: 10.1002/ece3.1264] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/05/2014] [Accepted: 09/10/2014] [Indexed: 11/28/2022] Open
Abstract
Parthenogenesis in animals is often associated with polyploidy and restriction to extreme habitats or recently deglaciated areas. It has been hypothesized that benefits conferred by asexual reproduction and polyploidy are essential for colonizing these habitats. However, while evolutionary routes to parthenogenesis are manifold, study systems including polyploids are scarce in arthropods. The jumping-bristletail genus Machilis (Insecta: Archaeognatha) includes both sexual and parthenogenetic species, and recently, the occurrence of polyploidy has been postulated. Here, we applied flow cytometry, karyotyping, and mitochondrial DNA sequencing to three sexual and five putatively parthenogenetic Eastern-Alpine Machilis species to investigate whether (1) parthenogenesis originated once or multiply and (2) whether parthenogenesis is strictly associated with polyploidy. The mitochondrial phylogeny revealed that parthenogenesis evolved at least five times independently among Eastern-Alpine representatives of this genus. One parthenogenetic species was exclusively triploid, while a second consisted of both diploid and triploid populations. The three other parthenogenetic species and all sexual species were diploid. Our results thus indicate that polyploidy can co-occur with parthenogenesis, but that it was not mandatory for the emergence of parthenogenesis in Machilis. Overall, we found a weak negative correlation of monoploid genome size (Cx) and chromosome base number (x), and this connection is stronger among parthenogenetic species alone. Likewise, monoploid genome size decreased with elevation, and we therefore hypothesize that genome downsizing could have been crucial for the persistence of alpine Machilis species. Finally, we discuss the evolutionary consequences of intraspecific chromosomal rearrangements and the presence of B chromosomes. In doing so, we highlight the potential of Alpine Machilis species for research on chromosomal and genome-size alterations during speciation.
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Affiliation(s)
- Melitta Gassner
- Institute of Ecology, University of Innsbruck Technikerstraße 25, Innsbruck, 6020, Austria
| | - Thomas Dejaco
- Institute of Ecology, University of Innsbruck Technikerstraße 25, Innsbruck, 6020, Austria
| | - Peter Schönswetter
- Institute of Botany, University of Innsbruck Sternwartestraße 15, Innsbruck, 6020, Austria
| | - František Marec
- Institute of Entomology, Biology Centre ASCR Branisovska 31, Ceské Budejovice, 37005, Czech Republic
| | - Wolfgang Arthofer
- Institute of Ecology, University of Innsbruck Technikerstraße 25, Innsbruck, 6020, Austria
| | | | - Florian M Steiner
- Institute of Ecology, University of Innsbruck Technikerstraße 25, Innsbruck, 6020, Austria
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14
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Genetic heterogeneity reveals on-going speciation and cryptic taxonomic diversity of stream-dwelling gudgeons (Teleostei, Cyprinidae) in the middle Danubian hydrosystem (Hungary). PLoS One 2014; 9:e97278. [PMID: 24824751 PMCID: PMC4019547 DOI: 10.1371/journal.pone.0097278] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Accepted: 04/18/2014] [Indexed: 11/19/2022] Open
Abstract
Although stream-dwelling gudgeons (Cyprinidae, genus: Gobio) are widespread in Central Europe, the taxonomy of this group and the distribution of its species are still unexplored in detail. The aims of our study are to ascertain taxonomic composition and distribution of the former Gobio gobio superspecies in the inner area of the Carpathian Basin. Since the presence of cryptic species is suspected in this area, we examined the taxonomic and phylogenetic relationships of Central European Gobio taxa by sequencing the mitochondrial DNA control region (mtCR). Additionally, we characterized the genetic structure of 27 stream-dwelling gudgeon populations of this area by Amplified Fragment Length Polymorphism (AFLP). Results of mtCR analysis proved the presence of three species already known as G. obtusirostris (dominant in NW-Hungary), G. gobio (sporadic) and G. carpathicus (sporadic). Additionally, the analysis revealed the existence of one doubtful taxon, G. sp1 (dominant in NE-Hungary), and a new isolated haplogroup (dominant in SW-Hungary). Although Network analysis showed significant detachment among haplogroups, their genetic distances were quite small. Therefore Bayesian phylogenetic analysis showed weak nodal support for the branching pattern both for newly described haplotypes, and for the already accepted species. AFLP data showed distinct population structure and a clear pattern of isolation was revealed by distance of stocks. At the same time, level of separation was not affected by the altitudinal position of sites. Moreover we found three major clusters of populations which were separated according to hydrographic regions, and corresponded to the findings of mtCR analysis. Our results suggest the on-going speciation of gudgeons in the Carpathian Basin, however the separation of haplogroups seems to only be an intermediate phase. The discovered natural pattern seems to be only slightly influenced by anthropogenic impacts. Additionally our results put into question the suitability of the recently accepted within Gobio genus taxonomy.
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Arthofer W, Rauch H, Thaler-Knoflach B, Moder K, Muster C, Schlick-Steiner BC, Steiner FM. How diverse isMitopus morio? Integrative taxonomy detects cryptic species in a small-scale sample of a widespread harvestman. Mol Ecol 2013; 22:3850-63. [DOI: 10.1111/mec.12340] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 04/04/2013] [Accepted: 04/08/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Wolfgang Arthofer
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstrasse 25, 6020 Innsbruck Austria
| | - Hannes Rauch
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstrasse 25, 6020 Innsbruck Austria
| | - Barbara Thaler-Knoflach
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstrasse 25, 6020 Innsbruck Austria
| | - Karl Moder
- Institute of Mathematics and Applied Statistics; Department of Spatial, Landscape, and Infrastructure Sciences; University of Natural Resources and Life Sciences; Peter Jordan-Strasse 82, 1180 Vienna Austria
| | - Christoph Muster
- General Zoology and Zoological Systematics; Zoological Institute and Museum; University of Greifswald; Johann Sebastian Bach-Str 11/12, 17487 Greifswald Germany
| | - Birgit C. Schlick-Steiner
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstrasse 25, 6020 Innsbruck Austria
| | - Florian M. Steiner
- Molecular Ecology Group; Institute of Ecology; University of Innsbruck; Technikerstrasse 25, 6020 Innsbruck Austria
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