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Bisconti M, Pellegrino L, Carnevale G. Evolution of gigantism in right and bowhead whales (Cetacea: Mysticeti: Balaenidae). Biol J Linn Soc Lond 2021. [DOI: 10.1093/biolinnean/blab086] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
The evolution of gigantic body size represents a key to understand the ecological role of baleen whales in oceanic ecosystems. Many efforts have been devoted to the formulation of equations relating different body parts to total body length and mass in living and fossil mysticetes, mainly focusing on balaenopterid and balaenopterid-like mysticetes. Right whales (family Balaenidae) have a unique head-to-body length ratio, suggesting that their body proportions cannot be predicted effectively using equations based primarily on non-balaenid mysticetes. A new morphometric dataset of living and fossil balaenids is provided herein, and new regression equations allow one to predict the body length and mass of extinct species based on the expected head-to-body length ratio of extant balaenids. The reconstructed values are mapped on a new phylogenetic analysis of the Balaenidae, inferring body size and mass at ancestral nodes. The variations of body size and mass in Balaenidae since the early Miocene are reconstructed, revealing that: (1) a reduction in total body length occurred in the early Pliocene; (2) the origin of the gigantic body size in the bowhead whale (Balaena mysticetus) is probably related to invasion of the Arctic Ocean in the last 3 Myr; and (3) the origin of the gigantic body size in the right whales (genus Eubalaena) occurred since the latest Miocene, probably concomitant with pulses of nutrients sustaining large zooplankton populations. We suggest that the evolution of gigantism in Balaenidae occurred independently in two lineages and, probably, in response to different palaeoenvironmental drivers.
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Affiliation(s)
- Michelangelo Bisconti
- Dipartimento di Scienze della Terra, Università degli Studi di Torino, via Valperga Caluso 35, 10125, Torino, Italy
- San Diego Natural History Museum, 1788 El Prado, San Diego, CA 92101, USA
| | - Luca Pellegrino
- Dipartimento di Scienze della Terra, Università degli Studi di Torino, via Valperga Caluso 35, 10125, Torino, Italy
| | - Giorgio Carnevale
- Dipartimento di Scienze della Terra, Università degli Studi di Torino, via Valperga Caluso 35, 10125, Torino, Italy
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2
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Klemme I, Hendrikx L, Ashrafi R, Sundberg L, Räihä V, Piironen J, Hyvärinen P, Karvonen A. Opposing health effects of hybridization for conservation. CONSERVATION SCIENCE AND PRACTICE 2021. [DOI: 10.1111/csp2.379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Ines Klemme
- Department of Biological and Environmental Science University of Jyvaskyla Jyvaskyla Finland
| | - Lysanne Hendrikx
- Department of Biological and Environmental Science University of Jyvaskyla Jyvaskyla Finland
| | - Roghaieh Ashrafi
- Department of Biological and Environmental Science University of Jyvaskyla Jyvaskyla Finland
| | - Lotta‐Riina Sundberg
- Department of Biological and Environmental Science University of Jyvaskyla Jyvaskyla Finland
| | - Ville Räihä
- Department of Biological and Environmental Science University of Jyvaskyla Jyvaskyla Finland
| | - Jorma Piironen
- Aquatic Population Dynamics Natural Resources Institute Paltamo Finland
| | - Pekka Hyvärinen
- Aquatic Population Dynamics Natural Resources Institute Paltamo Finland
| | - Anssi Karvonen
- Department of Biological and Environmental Science University of Jyvaskyla Jyvaskyla Finland
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3
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McGowen MR, Tsagkogeorga G, Álvarez-Carretero S, Dos Reis M, Struebig M, Deaville R, Jepson PD, Jarman S, Polanowski A, Morin PA, Rossiter SJ. Phylogenomic Resolution of the Cetacean Tree of Life Using Target Sequence Capture. Syst Biol 2020; 69:479-501. [PMID: 31633766 PMCID: PMC7164366 DOI: 10.1093/sysbio/syz068] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 10/02/2019] [Accepted: 10/06/2019] [Indexed: 12/20/2022] Open
Abstract
The evolution of cetaceans, from their early transition to an aquatic lifestyle to their subsequent diversification, has been the subject of numerous studies. However, although the higher-level relationships among cetacean families have been largely settled, several aspects of the systematics within these groups remain unresolved. Problematic clades include the oceanic dolphins (37 spp.), which have experienced a recent rapid radiation, and the beaked whales (22 spp.), which have not been investigated in detail using nuclear loci. The combined application of high-throughput sequencing with techniques that target specific genomic sequences provide a powerful means of rapidly generating large volumes of orthologous sequence data for use in phylogenomic studies. To elucidate the phylogenetic relationships within the Cetacea, we combined sequence capture with Illumina sequencing to generate data for \documentclass[12pt]{minimal}
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}{}$\sim $\end{document}3200 protein-coding genes for 68 cetacean species and their close relatives including the pygmy hippopotamus. By combining data from \documentclass[12pt]{minimal}
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}{}$>$\end{document}38,000 exons with existing sequences from 11 cetaceans and seven outgroup taxa, we produced the first comprehensive comparative genomic data set for cetaceans, spanning 6,527,596 aligned base pairs (bp) and 89 taxa. Phylogenetic trees reconstructed with maximum likelihood and Bayesian inference of concatenated loci, as well as with coalescence analyses of individual gene trees, produced mostly concordant and well-supported trees. Our results completely resolve the relationships among beaked whales as well as the contentious relationships among oceanic dolphins, especially the problematic subfamily Delphinidae. We carried out Bayesian estimation of species divergence times using MCMCTree and compared our complete data set to a subset of clocklike genes. Analyses using the complete data set consistently showed less variance in divergence times than the reduced data set. In addition, integration of new fossils (e.g., Mystacodon selenensis) indicates that the diversification of Crown Cetacea began before the Late Eocene and the divergence of Crown Delphinidae as early as the Middle Miocene. [Cetaceans; phylogenomics; Delphinidae; Ziphiidae; dolphins; whales.]
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Affiliation(s)
- Michael R McGowen
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK.,Department of Vertebrate Zoology, Smithsonian Museum of Natural History, 10th & Constitution Ave. NW, Washington DC 20560, USA
| | - Georgia Tsagkogeorga
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Sandra Álvarez-Carretero
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Mario Dos Reis
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Monika Struebig
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Robert Deaville
- Institute of Zoology, Zoological Society of London, Outer Circle, London NW1 4RY, UK
| | - Paul D Jepson
- Institute of Zoology, Zoological Society of London, Outer Circle, London NW1 4RY, UK
| | - Simon Jarman
- School of Biological Sciences, University of Western Australia, 35 Stirling Highway, Perth WA 6009, Australia
| | - Andrea Polanowski
- Australian Antarctic Division, 203 Channel Highway, Kingston TAS 7050, Australia
| | - Phillip A Morin
- Southwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 8901 La Jolla Shores Dr., La Jolla CA 92037 USA
| | - Stephen J Rossiter
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
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4
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Ramos R, Paiva VH, Zajková Z, Precheur C, Fagundes AI, Jodice PGR, Mackin W, Zino F, Bretagnolle V, González-Solís J. Spatial ecology of closely related taxa: the case of the little shearwater complex in the North Atlantic Ocean. Zool J Linn Soc 2020. [DOI: 10.1093/zoolinnean/zlaa045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Seabirds inhabiting vast water masses provide numerous examples where opposing phenomena, such as natal and breeding philopatry vs. vagility have dug cryptic taxonomic boundaries among closely related taxa. The taxonomy of little shearwaters of the North Atlantic Ocean (Little–Audubon’s shearwater complex, Puffinus assimilis–lherminieri) still remains unclear, and complementary information on non-breeding distributions and at-sea behaviour becomes essential to unravel divergent local adaptations to specific habitats. Using miniaturized light-level geolocators from seven study areas in the North Atlantic, we evaluate the spatial and habitat segregation, estimate the timing of their key life-cycle events and describe the at-sea behaviour of three taxa of these little shearwaters year-round to distinguish ecological patterns and specializations that could ultimately unravel potential lineage divergences. We also assess morphometric data from birds that were breeding at each study area to further discuss potential adaptations to specific habitats. Our results show that, while birds from different taxa segregated in space and habitats, they share ecological plasticity, similar annual phenology and diel foraging behaviour. These ecological inconsistencies, while defining the evolutionary stressors faced by these taxa, do not suggest the existence of three Evolutionary Significant Units. However, they confirm the recent evolutionary divergence among the three little shearwaters of the North Atlantic.
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Affiliation(s)
- Raül Ramos
- Institut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Universitat de Barcelona, Av Diagonal, Barcelona, Spain
| | - Vitor H Paiva
- University of Coimbra, MARE - Marine and Environmental Sciences Centre, Department of Life Sciences, Calçada Martim de Freitas, Coimbra, Portugal
| | - Zuzana Zajková
- Institut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Universitat de Barcelona, Av Diagonal, Barcelona, Spain
- Centre for Advanced Studies of Blanes (CEAB-CSIC), Accés Cala St. Francesc 14, Blanes, Spain
| | - Carine Precheur
- CEBC, UMR, CNRS & Université de La Rochelle, Villiers en Bois, France
- Laboratoire Biologie marine (EA926), Université des Antilles, Pointe-à-Pitre, Guadeloupe, France
| | - Ana Isabel Fagundes
- Portuguese Society for the Study of Birds (SPEA), Avenida Columbano Bordalo Pinheiro, Lisboa, Portugal
| | - Patrick G R Jodice
- US Geological Survey, South Carolina Cooperative Fish & Wildlife Research Unit, Clemson University, SC 29634 Clemson, South Carolina, USA
| | | | - Francis Zino
- Freira Conservation Project (FCP), Avenida do Infante, Funchal, Madeira, Portugal
| | | | - Jacob González-Solís
- Institut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Universitat de Barcelona, Av Diagonal, Barcelona, Spain
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5
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Tsai CH, Chang CH. A right whale (Mysticeti, Balaenidae) from the Pleistocene of Taiwan. ZOOLOGICAL LETTERS 2019; 5:37. [PMID: 31890275 PMCID: PMC6935478 DOI: 10.1186/s40851-019-0153-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
Current patterns of biological distribution result from the deep past. Of particular interest, some closely related species appear at high latitudes of both hemispheres, but not in between, a pattern known as antitropical distribution. However, the timing, pathway, and drivers of antitropical distributions remain mostly unknown. Here we describe a new fossil, a left tympanic bulla (part of the ear bones), from the Middle/Late Pleistocene (0.78-0.01 mya, but not excluding the possibility of Holocene in age, as the specimen was dredged from the sea bottom and the geological horizon remains uncertain) of Taiwan. The tympanic bulla is diagnostic in baleen whales, and this specimen shows morphological features that are identical to extant Eubalaena, including: relatively large size (the anteroposterior length is 117 mm); rectangular outline in medial view; short anterior lobe, judging from the remaining of the lateral furrow; squared anterior margin; prominent transverse crease on the involucrum; transversely compressed in anterior view; well-developed and rounded outer lip; and parallel involucral and main ridges. Although incomplete, the morphological characters and overall similarity to extant Eubalaena allow a reliable taxonomic assignment to Eubalaena sp. The occurrence of a Pleistocene Eubalaena on the southern margin of the western North Pacific is the first balaenid fossil evidence indicative of the biotic interchange between two hemispheres leading to the origin of antitropical distribution in the Pleistocene; alternatively, this specimen might merely represent an extra-limital record of the North Pacific Eubalaena. Furthermore, this find suggests that the Eubalaena interchange, being one of the largest species displaying antitropical distribution pairs in the history of life, likely took place along the western Pacific. Notably, this does not preclude the Eubalaena interchange from other routes, such as the eastern Pacific or the Atlantic Ocean, and future finds should test the scenario for the biotic interchange between Northern and Southern Hemispheres of Eubalaena.
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Affiliation(s)
- Cheng-Hsiu Tsai
- Department of Life Science, National Taiwan University, Taipei, 10617 Taiwan
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, 10617 Taiwan
| | - Chun-Hsiang Chang
- Department of Geology, National Museum of Natural Science, Taichung, 40453 Taiwan
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7
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Roques S, Chancerel E, Boury C, Pierre M, Acolas M. From microsatellites to single nucleotide polymorphisms for the genetic monitoring of a critically endangered sturgeon. Ecol Evol 2019; 9:7017-7029. [PMID: 31380030 PMCID: PMC6662312 DOI: 10.1002/ece3.5268] [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: 06/11/2018] [Revised: 02/12/2019] [Accepted: 04/04/2019] [Indexed: 01/06/2023] Open
Abstract
The use of genetic information is crucial in conservation programs for the establishment of breeding plans and for the evaluation of restocking success. Short tandem repeats (STRs) have been the most widely used molecular markers in such programs, but next-generation sequencing approaches have prompted the transition to genome-wide markers such as single nucleotide polymorphisms (SNPs). Until now, most sturgeon species have been monitored using STRs. The low diversity found in the critically endangered European sturgeon (Acipenser sturio), however, makes its future genetic monitoring challenging, and the current resolution needs to be increased. Here, we describe the discovery of a highly informative set of 79 SNPs using double-digest restriction-associated DNA (ddRAD) sequencing and its validation by genotyping using the MassARRAY system. Comparing with STRs, the SNP panel proved to be highly efficient and reproducible, allowing for more accurate parentage and kinship assignments' on 192 juveniles of known pedigree and 40 wild-born adults. We explore the effectiveness of both markers to estimated relatedness and inbreeding, using simulated and empirical datasets. Interestingly, we found significant correlations between STRs and SNPs at individual heterozygosity and inbreeding that give support to a reasonable representation of whole genome diversity for both markers. These results are useful for the conservation program of A. sturio in building a comprehensive studbook, which will optimize conservation strategies. This approach also proves suitable for other case studies in which highly discriminatory genetic markers are needed to assess parentage and kinship.
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Affiliation(s)
- Séverine Roques
- Aquatic Ecosystems and Global ChangesIRSTEA, EABX URCestasFrance
| | | | | | - Maud Pierre
- Aquatic Ecosystems and Global ChangesIRSTEA, EABX URCestasFrance
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Lemopoulos A, Prokkola JM, Uusi‐Heikkilä S, Vasemägi A, Huusko A, Hyvärinen P, Koljonen M, Koskiniemi J, Vainikka A. Comparing RADseq and microsatellites for estimating genetic diversity and relatedness - Implications for brown trout conservation. Ecol Evol 2019; 9:2106-2120. [PMID: 30847096 PMCID: PMC6392366 DOI: 10.1002/ece3.4905] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 11/30/2018] [Accepted: 12/21/2018] [Indexed: 12/24/2022] Open
Abstract
The conservation and management of endangered species requires information on their genetic diversity, relatedness and population structure. The main genetic markers applied for these questions are microsatellites and single nucleotide polymorphisms (SNPs), the latter of which remain the more resource demanding approach in most cases. Here, we compare the performance of two approaches, SNPs obtained by restriction-site-associated DNA sequencing (RADseq) and 16 DNA microsatellite loci, for estimating genetic diversity, relatedness and genetic differentiation of three, small, geographically close wild brown trout (Salmo trutta) populations and a regionally used hatchery strain. The genetic differentiation, quantified as F ST, was similar when measured using 16 microsatellites and 4,876 SNPs. Based on both marker types, each brown trout population represented a distinct gene pool with a low level of interbreeding. Analysis of SNPs identified half- and full-siblings with a higher probability than the analysis based on microsatellites, and SNPs outperformed microsatellites in estimating individual-level multilocus heterozygosity. Overall, the results indicated that moderately polymorphic microsatellites and SNPs from RADseq agreed on estimates of population genetic structure in moderately diverged, small populations, but RADseq outperformed microsatellites for applications that required individual-level genotype information, such as quantifying relatedness and individual-level heterozygosity. The results can be applied to other small populations with low or moderate levels of genetic diversity.
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Affiliation(s)
- Alexandre Lemopoulos
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandJoensuuFinland
- Department of BiologyUniversity of TurkuTurkuFinland
| | - Jenni M. Prokkola
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandJoensuuFinland
- Institute of Integrative BiologyUniversity of LiverpoolLiverpoolUK
| | - Silva Uusi‐Heikkilä
- Department of BiologyUniversity of TurkuTurkuFinland
- Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskyläFinland
| | - Anti Vasemägi
- Department of BiologyUniversity of TurkuTurkuFinland
- Department of Aquatic Resources, Institute of Freshwater ResearchSwedish University of Agricultural SciencesDrottningholmSweden
- Estonian University of Life SciencesInstitute of Veterinary Medicine and Animal SciencesTartuEstonia
| | - Ari Huusko
- Natural Resources Institute Finland (Luke), Kainuu Fisheries Research StationPaltamoFinland
| | - Pekka Hyvärinen
- Natural Resources Institute Finland (Luke), Kainuu Fisheries Research StationPaltamoFinland
| | | | - Jarmo Koskiniemi
- Department of Agricultural SciencesUniversity of HelsinkiHelsinkiFinland
| | - Anssi Vainikka
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandJoensuuFinland
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9
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Bisconti M, Lambert O, Bosselaers M. Revision of " Balaena" belgica reveals a new right whale species, the possible ancestry of the northern right whale, Eubalaena glacialis, and the ages of divergence for the living right whale species. PeerJ 2017; 5:e3464. [PMID: 28663936 PMCID: PMC5490463 DOI: 10.7717/peerj.3464] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/24/2017] [Indexed: 12/03/2022] Open
Abstract
In 1941, Abel established Balaena belgica based on a series of fused cervical vertebrae and citing other cranial fragments from the late Neogene of the Antwerp harbor (northern Belgium). Later, Plisnier-Ladame & Quinet (1969) added a neurocranium and other skeletal remains from the same area to this species. Recently, the neurocranium was re-assigned to the genus Eubalaena thanks to newer phylogenetic analyses. Here, a new description is provided of materials previously assigned to “Balaena” belgica together with taxonomic revisions. Our work suggests that the cervical complex originally designated as the type of “Balaena” belgica is too poorly preserved to be used as such and is assigned to Balaenidae gen. et sp. indet., thus making “Balaena” belgica a nomen dubium. In addition to the neurocranium, the other remains consist in a fragment of maxilla assigned to Balaenidae gen. et sp. indet. and in a humerus assigned to Eubalaena sp. Discovered in the Kruisschans Sands Member of the Lillo Formation (3.2–2.8 Ma, Piacenzian, Late Pliocene), the neurocranium is designated as the holotype of the new species Eubalaena ianitrix. Our phylogenetic analysis supports a sister-group relationship of Eubalaena ianitrix and Eubalaena glacialis, and helps constraining the ages of origin for balaenid clades. Ecological and phylogenetic data suggest that Eubalaena ianitrix may represent the direct ancestor of Eubalaena glacialis, the latter having evolved through phyletic transformation including body size increase during the temperature decline of the Late Pliocene.
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Affiliation(s)
| | - Olivier Lambert
- Royal Belgian Institute of Natural Sciences, Brussels, Belgium
| | - Mark Bosselaers
- Royal Belgian Institute of Natural Sciences, Brussels, Belgium.,Zeeland Royal Society of Sciences, Middelburg, the Netherlands
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10
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Viengkone M, Derocher AE, Richardson ES, Malenfant RM, Miller JM, Obbard ME, Dyck MG, Lunn NJ, Sahanatien V, Davis CS. Assessing polar bear ( Ursus maritimus) population structure in the Hudson Bay region using SNPs. Ecol Evol 2016; 6:8474-8484. [PMID: 28031799 PMCID: PMC5167041 DOI: 10.1002/ece3.2563] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Revised: 09/14/2016] [Accepted: 09/20/2016] [Indexed: 12/28/2022] Open
Abstract
Defining subpopulations using genetics has traditionally used data from microsatellite markers to investigate population structure; however, single‐nucleotide polymorphisms (SNPs) have emerged as a tool for detection of fine‐scale structure. In Hudson Bay, Canada, three polar bear (Ursus maritimus) subpopulations (Foxe Basin (FB), Southern Hudson Bay (SH), and Western Hudson Bay (WH)) have been delineated based on mark–recapture studies, radiotelemetry and satellite telemetry, return of marked animals in the subsistence harvest, and population genetics using microsatellites. We used SNPs to detect fine‐scale population structure in polar bears from the Hudson Bay region and compared our results to the current designations using 414 individuals genotyped at 2,603 SNPs. Analyses based on discriminant analysis of principal components (DAPC) and STRUCTURE support the presence of four genetic clusters: (i) Western—including individuals sampled in WH, SH (excluding Akimiski Island in James Bay), and southern FB (south of Southampton Island); (ii) Northern—individuals sampled in northern FB (Baffin Island) and Davis Strait (DS) (Labrador coast); (iii) Southeast—individuals from SH (Akimiski Island in James Bay); and (iv) Northeast—individuals from DS (Baffin Island). Population structure differed from microsatellite studies and current management designations demonstrating the value of using SNPs for fine‐scale population delineation in polar bears.
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Affiliation(s)
- Michelle Viengkone
- Department of Biological Sciences University of Alberta Edmonton AB Canada
| | | | - Evan Shaun Richardson
- Wildlife Research Division Science and Technology Branch Environment and Climate Change Canada University of Alberta Edmonton AB Canada
| | - René Michael Malenfant
- Department of Biological Sciences University of Alberta Edmonton AB Canada; Department of Biology University of New Brunswick Fredericton NB Canada
| | - Joshua Moses Miller
- Department of Biological Sciences University of Alberta Edmonton AB Canada; Department of Ecology and Evolutionary Biology Yale University New Haven CT USA
| | - Martyn E Obbard
- Wildlife Research and Monitoring Section Ontario Ministry of Natural Resources and Forestry Trent University Peterborough ON Canada
| | - Markus G Dyck
- Department of Environment Government of Nunavut Igloolik NU Canada
| | - Nick J Lunn
- Wildlife Research Division Science and Technology Branch Environment and Climate Change Canada University of Alberta Edmonton AB Canada
| | - Vicki Sahanatien
- Department of Biological Sciences University of Alberta Edmonton AB Canada
| | - Corey S Davis
- Department of Biological Sciences University of Alberta Edmonton AB Canada
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11
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Elbers JP, Clostio RW, Taylor SS. Population genetic inferences using immune gene SNPs mirror patterns inferred by microsatellites. Mol Ecol Resour 2016; 17:481-491. [PMID: 27488693 DOI: 10.1111/1755-0998.12591] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 12/11/2022]
Abstract
Single nucleotide polymorphisms (SNPs) are replacing microsatellites for population genetic analyses, but it is not apparent how many SNPs are needed or how well SNPs correlate with microsatellites. We used data from the gopher tortoise, Gopherus polyphemus-a species with small populations, to compare SNPs and microsatellites to estimate population genetic parameters. Specifically, we compared one SNP data set (16 tortoises from four populations sequenced at 17 901 SNPs) to two microsatellite data sets, a full data set of 101 tortoises and a partial data set of 16 tortoises previously genotyped at 10 microsatellites. For the full microsatellite data set, observed heterozygosity, expected heterozygosity and FST were correlated between SNPs and microsatellites; however, allelic richness was not. The same was true for the partial microsatellite data set, except that allelic richness, but not observed heterozygosity, was correlated. The number of clusters estimated by structure differed for each data set (SNPs = 2; partial microsatellite = 3; full microsatellite = 4). Principle component analyses (PCA) showed four clusters for all data sets. More than 800 SNPs were needed to correlate with allelic richness, observed heterozygosity and expected heterozygosity, but only 100 were needed for FST . The number of SNPs typically obtained from next-generation sequencing (NGS) far exceeds the number needed to correlate with microsatellite parameter estimates. Our study illustrates that diversity, FST and PCA results from microsatellites can mirror those obtained with SNPs. These results may be generally applicable to small populations, a defining feature of endangered and threatened species, because theory predicts that genetic drift will tend to outweigh selection in small populations.
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Affiliation(s)
- Jean P Elbers
- School of Renewable Natural Resources, Louisiana State University and AgCenter, 227 RNR Bldg., Baton Rouge, LA, 70803, USA
| | - Rachel W Clostio
- Department of Biology, University of Louisiana at Lafayette, 300 E. Street Mary Blvd., Lafayette, LA, 70503, USA
| | - Sabrina S Taylor
- School of Renewable Natural Resources, Louisiana State University and AgCenter, 227 RNR Bldg., Baton Rouge, LA, 70803, USA
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12
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Ramos R, Ramírez I, Paiva VH, Militão T, Biscoito M, Menezes D, Phillips RA, Zino F, González-Solís J. Global spatial ecology of three closely-related gadfly petrels. Sci Rep 2016; 6:23447. [PMID: 27001141 PMCID: PMC4802315 DOI: 10.1038/srep23447] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 03/03/2016] [Indexed: 11/23/2022] Open
Abstract
The conservation status and taxonomy of the three gadfly petrels that breed in Macaronesia is still discussed partly due to the scarce information on their spatial ecology. Using geolocator and capture-mark-recapture data, we examined phenology, natal philopatry and breeding-site fidelity, year-round distribution, habitat usage and at-sea activity of the three closely-related gadfly petrels that breed in Macaronesia: Zino’s petrel Pterodroma madeira, Desertas petrel P. deserta and Cape Verde petrel P. feae. All P. feae remained around the breeding area during their non-breeding season, whereas P. madeira and P. deserta dispersed far from their colony, migrating either to the Cape Verde region, further south to equatorial waters in the central Atlantic, or to the Brazil Current. The three taxa displayed a clear allochrony in timing of breeding. Habitat modelling and at-sea activity patterns highlighted similar environmental preferences and foraging behaviours of the three taxa. Finally, no chick or adult was recaptured away from its natal site and survival estimates were relatively high at all study sites, indicating strong philopatry and breeding-site fidelity for the three taxa. The combination of high philopatry, marked breeding asynchrony and substantial spatio-temporal segregation of their year-round distribution suggest very limited gene flow among the three taxa.
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Affiliation(s)
- Raül Ramos
- Institut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Animal, Universitat de Barcelona, Av Diagonal 643, Barcelona 08028, Spain
| | - Iván Ramírez
- BirdLife International-The David Attenborough Building, Pembroke St, Cambridge, CB2 3QZ, United Kingdom
| | - Vitor H Paiva
- Marine and Environmental Sciences Centre (MARE), Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Teresa Militão
- Institut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Animal, Universitat de Barcelona, Av Diagonal 643, Barcelona 08028, Spain
| | - Manuel Biscoito
- Marine and Environmental Sciences Centre (MARE), Estação de Biologia Marinha do Funchal and OOM-Museu de História Natural do Funchal, Rua da Mouraria 31, Funchal 9004-546, Madeira, Portugal.,Freira Conservation Project (FCP), Avenida do Infante 26, 9000-015 Funchal, Madeira, Portugal
| | - Dília Menezes
- Parque Natural da Madeira, Quinta do Bom Sucesso, Caminho do Meio, Funchal 9050-251, Madeira, Portugal
| | - Richard A Phillips
- British Antarctic Survey (BAS), Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, United Kingdom
| | - Francis Zino
- Marine and Environmental Sciences Centre (MARE), Estação de Biologia Marinha do Funchal and OOM-Museu de História Natural do Funchal, Rua da Mouraria 31, Funchal 9004-546, Madeira, Portugal.,Freira Conservation Project (FCP), Avenida do Infante 26, 9000-015 Funchal, Madeira, Portugal
| | - Jacob González-Solís
- Institut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Animal, Universitat de Barcelona, Av Diagonal 643, Barcelona 08028, Spain
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13
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Dierickx EG, Shultz AJ, Sato F, Hiraoka T, Edwards SV. Morphological and genomic comparisons of Hawaiian and Japanese Black-footed Albatrosses (Phoebastria nigripes) using double digest RADseq: implications for conservation. Evol Appl 2015; 8:662-78. [PMID: 26240604 PMCID: PMC4516419 DOI: 10.1111/eva.12274] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 04/14/2015] [Indexed: 01/01/2023] Open
Abstract
Evaluating the genetic and demographic independence of populations of threatened species is important for determining appropriate conservation measures, but different technologies can yield different conclusions. Despite multiple studies, the taxonomic status and extent of gene flow between the main breeding populations of Black-footed Albatross (Phoebastria nigripes), a Near-Threatened philopatric seabird, are still controversial. Here, we employ double digest RADseq to quantify the extent of genomewide divergence and gene flow in this species. Our genomewide data set of 9760 loci containing 3455 single nucleotide polymorphisms yielded estimates of genetic diversity and gene flow that were generally robust across seven different filtering and sampling protocols and suggest a low level of genomic variation (θ per site = ∼0.00002-0.00028), with estimates of effective population size (N e = ∼500-15 881) falling far below current census size. Genetic differentiation was small but detectable between Japan and Hawaii (F ST ≈ 0.038-0.049), with no F ST outliers. Additionally, using museum specimens, we found that effect sizes of morphological differences by sex or population rarely exceeded 4%. These patterns suggest that the Hawaiian and Japanese populations exhibit small but significant differences and should be considered separate management units, although the evolutionary and adaptive consequences of this differentiation remain to be identified.
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Affiliation(s)
- Elisa G Dierickx
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University Cambridge, MA, USA ; Department of Zoology, University of Cambridge Cambridge, UK
| | - Allison J Shultz
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University Cambridge, MA, USA
| | - Fumio Sato
- Yamashina Institute for Ornithology Abiko, Japan
| | | | - Scott V Edwards
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University Cambridge, MA, USA
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14
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Olsen MT, Pampoulie C, Daníelsdóttir AK, Lidh E, Bérubé M, Víkingsson GA, Palsbøll PJ. Fin whale MDH-1 and MPI allozyme variation is not reflected in the corresponding DNA sequences. Ecol Evol 2014; 4:1787-803. [PMID: 24963377 PMCID: PMC4063476 DOI: 10.1002/ece3.1046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 02/07/2014] [Indexed: 11/07/2022] Open
Abstract
The appeal of genetic inference methods to assess population genetic structure and guide management efforts is grounded in the correlation between the genetic similarity and gene flow among populations. Effects of such gene flow are typically genomewide; however, some loci may appear as outliers, displaying above or below average genetic divergence relative to the genomewide level. Above average population, genetic divergence may be due to divergent selection as a result of local adaptation. Consequently, substantial efforts have been directed toward such outlying loci in order to identify traits subject to local adaptation. Here, we report the results of an investigation into the molecular basis of the substantial degree of genetic divergence previously reported at allozyme loci among North Atlantic fin whale (Balaenoptera physalus) populations. We sequenced the exons encoding for the two most divergent allozyme loci (MDH-1 and MPI) and failed to detect any nonsynonymous substitutions. Following extensive error checking and analysis of additional bioinformatic and morphological data, we hypothesize that the observed allozyme polymorphisms may reflect phenotypic plasticity at the cellular level, perhaps as a response to nutritional stress. While such plasticity is intriguing in itself, and of fundamental evolutionary interest, our key finding is that the observed allozyme variation does not appear to be a result of genetic drift, migration, or selection on the MDH-1 and MPI exons themselves, stressing the importance of interpreting allozyme data with caution. As for North Atlantic fin whale population structure, our findings support the low levels of differentiation found in previous analyses of DNA nucleotide loci.
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Affiliation(s)
- Morten Tange Olsen
- Evolutionary Genetics Group, Department of Genetics, Microbiology, and Toxicology, Stockholm University Svante Arrhenius Väg 20C, S-106 91 Stockholm, Sweden
| | | | | | - Emmelie Lidh
- Evolutionary Genetics Group, Department of Genetics, Microbiology, and Toxicology, Stockholm University Svante Arrhenius Väg 20C, S-106 91 Stockholm, Sweden
| | - Martine Bérubé
- Evolutionary Genetics Group, Department of Genetics, Microbiology, and Toxicology, Stockholm University Svante Arrhenius Väg 20C, S-106 91 Stockholm, Sweden ; Marine Evolution and Conservation, Centre for Ecological and Evolutionary Studies, University of Groningen PO Box 11103, 9700 CC, Groningen, The Netherlands
| | | | - Per J Palsbøll
- Evolutionary Genetics Group, Department of Genetics, Microbiology, and Toxicology, Stockholm University Svante Arrhenius Väg 20C, S-106 91 Stockholm, Sweden ; Marine Evolution and Conservation, Centre for Ecological and Evolutionary Studies, University of Groningen PO Box 11103, 9700 CC, Groningen, The Netherlands
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15
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Gillett RM, Murray BW, White BN. Characterization of class I- and class II-like major histocompatibility complex loci in pedigrees of North Atlantic right whales. J Hered 2013; 105:188-202. [PMID: 24381183 DOI: 10.1093/jhered/est095] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
North Atlantic right whales have one of the lowest levels of genetic variation at minisatellite loci, microsatellite loci, and mitochondrial control region haplotypes among mammals. Here, adaptive variation at the peptide binding region of class I and class II DRB-like genes of the major histocompatibility complex was assessed. Amplification of a duplicated region in 222 individuals revealed at least 11 class II alleles. Six alleles were assigned to the locus Eugl-DRB1 and 5 alleles were assigned to the locus Eugl-DRB2 by assessing segregation patterns of alleles from 81 parent/offspring pedigrees. Pedigree analysis indicated that these alleles segregated into 12 distinct haplotypes. Genotyping a smaller subset of unrelated individuals (n = 5 and 10, respectively) using different primer sets revealed at least 2 class II pseudogenes (with ≥ 4 alleles) and at least 3 class I loci (with ≥ 6 alleles). Class II sequences were significantly different from neutrality at peptide binding sites suggesting loci may be under the influence of balancing selection. Trans-species sharing of alleles was apparent for class I and class II sequences. Characterization of class II loci represents the first step in determining the relationship between major histocompatibility complex variability and factors affecting health and reproduction in this species.
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Affiliation(s)
- Roxanne M Gillett
- the Natural Resources DNA Profiling and Forensic Centre, Department of Biology, Trent University, 2140 East Bank Drive, Peterborough, Ontario K9J 7B8, Canada
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16
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Mendez M, Jefferson TA, Kolokotronis SO, Krützen M, Parra GJ, Collins T, Minton G, Baldwin R, Berggren P, Särnblad A, Amir OA, Peddemors VM, Karczmarski L, Guissamulo A, Smith B, Sutaria D, Amato G, Rosenbaum HC. Integrating multiple lines of evidence to better understand the evolutionary divergence of humpback dolphins along their entire distribution range: a new dolphin species in Australian waters? Mol Ecol 2013; 22:5936-48. [PMID: 24268046 DOI: 10.1111/mec.12535] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 08/12/2013] [Accepted: 09/14/2013] [Indexed: 01/14/2023]
Abstract
The conservation of humpback dolphins, distributed in coastal waters of the Indo-West Pacific and eastern Atlantic Oceans, has been hindered by a lack of understanding about the number of species in the genus (Sousa) and their population structure. To address this issue, we present a combined analysis of genetic and morphologic data collected from beach-cast, remote-biopsied and museum specimens from throughout the known Sousa range. We extracted genetic sequence data from 235 samples from extant populations and explored the mitochondrial control region and four nuclear introns through phylogenetic, population-level and population aggregation frameworks. In addition, 180 cranial specimens from the same geographical regions allowed comparisons of 24 morphological characters through multivariate analyses. The genetic and morphological data showed significant and concordant patterns of geographical segregation, which are typical for the kind of demographic isolation displayed by species units, across the Sousa genus distribution range. Based on our combined genetic and morphological analyses, there is convincing evidence for at least four species within the genus (S. teuszii in the Atlantic off West Africa, S. plumbea in the central and western Indian Ocean, S. chinensis in the eastern Indian and West Pacific Oceans, and a new as-yet-unnamed species off northern Australia).
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Affiliation(s)
- Martin Mendez
- Sackler Institute for Comparative Genomics, American Museum of Natural History, Central Park West at 79th Street, New York, NY, 10024, USA; Wildlife Conservation Society, 2300 Southern Boulevard, Bronx, New York, 10460, USA
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17
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Kershaw F, Leslie MS, Collins T, Mansur RM, Smith BD, Minton G, Baldwin R, LeDuc RG, Anderson RC, Brownell RL, Rosenbaum HC. Population Differentiation of 2 Forms of Bryde’s Whales in the Indian and Pacific Oceans. J Hered 2013; 104:755-64. [DOI: 10.1093/jhered/est057] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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18
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Mitogenomic phylogenetics of fin whales (Balaenoptera physalus spp.): genetic evidence for revision of subspecies. PLoS One 2013; 8:e63396. [PMID: 23691042 PMCID: PMC3656932 DOI: 10.1371/journal.pone.0063396] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 04/02/2013] [Indexed: 11/19/2022] Open
Abstract
There are three described subspecies of fin whales (Balaenoptera physalus): B. p. physalus Linnaeus, 1758 in the Northern Hemisphere, B. p. quoyi Fischer, 1829 in the Southern Hemisphere, and a recently described pygmy form, B. p. patachonica Burmeister, 1865. The discrete distribution in the North Pacific and North Atlantic raises the question of whether a single Northern Hemisphere subspecies is valid. We assess phylogenetic patterns using ~16 K base pairs of the complete mitogenome for 154 fin whales from the North Pacific, North Atlantic--including the Mediterranean Sea--and Southern Hemisphere. A Bayesian tree of the resulting 136 haplotypes revealed several well-supported clades representing each ocean basin, with no haplotypes shared among ocean basins. The North Atlantic haplotypes (n = 12) form a sister clade to those from the Southern Hemisphere (n = 42). The estimated time to most recent common ancestor (TMRCA) for this Atlantic/Southern Hemisphere clade and 81 of the 97 samples from the North Pacific was approximately 2 Ma. 14 of the remaining North Pacific samples formed a well-supported clade within the Southern Hemisphere. The TMRCA for this node suggests that at least one female from the Southern Hemisphere immigrated to the North Pacific approximately 0.37 Ma. These results provide strong evidence that North Pacific and North Atlantic fin whales should not be considered the same subspecies, and suggest the need for revision of the global taxonomy of the species.
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19
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DeFaveri J, Viitaniemi H, Leder E, Merilä J. Characterizing genic and nongenic molecular markers: comparison of microsatellites and
SNP
s. Mol Ecol Resour 2013; 13:377-92. [DOI: 10.1111/1755-0998.12071] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 12/04/2012] [Accepted: 12/11/2012] [Indexed: 11/30/2022]
Affiliation(s)
- Jacquelin DeFaveri
- Department of Biosciences Ecological Genetics Research Unit University of Helsinki PO Box 65 Helsinki FI‐00014 Finland
| | - Heidi Viitaniemi
- Division of Genetics and Physiology Department of Biology University of Turku PL 33 Turku FI‐00014 Finland
| | - Erica Leder
- Division of Genetics and Physiology Department of Biology University of Turku PL 33 Turku FI‐00014 Finland
| | - Juha Merilä
- Department of Biosciences Ecological Genetics Research Unit University of Helsinki PO Box 65 Helsinki FI‐00014 Finland
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20
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de OLIVEIRA LR, LOIZAGA DE CASTRO R, CÁRDENAS-ALAYZA S, BONATTO SL. Conservation genetics of South American aquatic mammals: an overview of gene diversity, population structure, phylogeography, non-invasive methods and forensics. Mamm Rev 2011. [DOI: 10.1111/j.1365-2907.2011.00201.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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Puillandre N, Meyer CP, Bouchet P, Olivera BM. Genetic divergence and geographic variation in the deep-water Conus orbignyi complex (Mollusca: Conoidea). ZOOL SCR 2011; 40:350-363. [PMID: 21712968 PMCID: PMC3123138 DOI: 10.1111/j.1463-6409.2011.00478.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Puillandre, N. et al. (2010) Genetic divergence and geographic variation in a deep-water cone lineage: molecular and morphological analyses of the Conus orbignyi complex (Mollusca: Conoidea).The cone snails (family Conidae) are a hyperdiverse lineage of venomous gastropods. Two standard markers, COI and ITS2, were used to define six genetically-divergent groups within a subclade of Conidae that includes Conus orbignyi; each of these was then evaluated based on their shell morphology. We conclude that three forms, previously regarded as subspecies of Conus orbignyi are distinct species, now recognized as Conus orbignyi, Conus elokismenos and Conus coriolisi. In addition, three additional species (Conus pseudorbignyi, Conus joliveti and Conus comatosa) belong to this clade. Some of the proposed species (e.g., Conus elokismenos) are possibly in turn complexes comprising multiple species. Groups such as Conidae illustrate the challenges generally faced in species delimitation in biodiverse lineages. In the case of the Conus orbignyi complex, not only are there definable, genetically divergent lineages, but also considerable geographic variation within each group. Our study suggests that an intensive analysis of multiple specimens within a single locality helps to minimize the confounding effects of geographic variation and can be a useful starting point for circumscribing different species within such a confusing complex.
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Affiliation(s)
- Nicolas Puillandre
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA
- Muséum National d’Histoire Naturelle, 55, Rue Buffon, 75005 Paris, FRANCE
| | - Christopher P. Meyer
- Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA
| | - Philippe Bouchet
- Muséum National d’Histoire Naturelle, 55, Rue Buffon, 75005 Paris, FRANCE
| | - Baldomero M. Olivera
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA
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22
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Guichoux E, Lagache L, Wagner S, Chaumeil P, Léger P, Lepais O, Lepoittevin C, Malausa T, Revardel E, Salin F, Petit RJ. Current trends in microsatellite genotyping. Mol Ecol Resour 2011; 11:591-611. [PMID: 21565126 DOI: 10.1111/j.1755-0998.2011.03014.x] [Citation(s) in RCA: 435] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Microsatellites have been popular molecular markers ever since their advent in the late eighties. Despite growing competition from new genotyping and sequencing techniques, the use of these versatile and cost-effective markers continues to increase, boosted by successive technical advances. First, methods for multiplexing PCR have considerably improved over the last years, thereby decreasing genotyping costs and increasing throughput. Second, next-generation sequencing technologies allow the identification of large numbers of microsatellite loci at reduced cost in non-model species. As a consequence, more stringent selection of loci is possible, thereby further enhancing multiplex quality and efficiency. However, current practices are lagging behind. By surveying recently published population genetic studies relying on simple sequence repeats, we show that more than half of the studies lack appropriate quality controls and do not make use of multiplex PCR. To make the most of the latest technical developments, we outline the need for a well-established strategy including standardized high-throughput bench protocols and specific bioinformatic tools, from primer design to allele calling.
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Affiliation(s)
- E Guichoux
- INRA, UMR 1202 Biodiversity Genes & Communities, F-33610 Cestas, France
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23
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Caballero S, Baker CS. Captive-born intergeneric hybrid of a Guiana and bottlenose dolphin: Sotalia guianensis x Tursiops truncatus. Zoo Biol 2011; 29:647-57. [PMID: 20033990 DOI: 10.1002/zoo.20299] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Bottlenose dolphins (Tursiops truncatus) and Guiana dolphin (Sotalia guianensis) live in sympatry along the Caribbean Coast of Central and South America and social interactions between these species have been described in the Caribbean Coast of Costa Rica, including sexual encounters. Here we examine and document the only known hybridization event between a male Guiana dolphin and a female bottlenose dolphin, in captivity at Oceanario Islas del Rosario (Colombian Caribbean), using photographic and genetic evidence from mitochondrial DNA markers and nuclear autosomal introns.
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Affiliation(s)
- S Caballero
- Laboratory of Molecular Ecology and Evolution, School of Biological Sciences, University of Auckland, Auckland, New Zealand.
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24
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Rakotoarisoa JE, Raheriarisena M, Goodman SM. Phylogeny and species boundaries of the endemic species complex, Eliurus antsingy and E. carletoni (Rodentia: Muroidea: Nesomyidae), in Madagascar using mitochondrial and nuclear DNA sequence data. Mol Phylogenet Evol 2010; 57:11-22. [PMID: 20685291 DOI: 10.1016/j.ympev.2010.05.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 05/18/2010] [Accepted: 05/24/2010] [Indexed: 01/29/2023]
Abstract
Current understanding of the taxonomy and species relationships within the genus Eliurus, a member of the endemic Malagasy rodent subfamily Nesomyinae, is largely based on morphological characters. Little has been published about the historical biogeography and diversification factors in members of this genus. Here we examined, using molecular data, the evolutionary relationships, and species boundaries within a species complex of Eliurus and the role of rivers in their evolution. Specifically, we tested the hypothesized monophyly of E. antsingy (west) and the recently described E. carletoni (north) using two mitochondrial genes, cytochrome b, the control region, and a nuclear marker, the Interstitial Retinol Binding Protein (IRBP). We also assessed the species boundaries of E. carletoni and examined phylogeographic patterns using two mitochondrial markers and an extensive geographic sampling. Molecular data show that members of the E. antsingy and E. carletoni complex together form a monophyletic group. Although samples provisionally assigned to E. carletoni based on morphological characters from different sites in northern Madagascar cluster in three separate phylogroups, they are monophyletic and assignable to this species. Rivers do not act as strict barriers to dispersal in E. carletoni. The demonstrated monophyly of both E. antsingy and E. carletoni contributes to the amounting evidence for a biogeographic link between the north and western regions of the island.
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25
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Rugman-Jones PF, Hoddle MS, Stouthamer R. Nuclear-mitochondrial barcoding exposes the global pest Western flower thrips (Thysanoptera: Thripidae) as two sympatric cryptic species in its native California. JOURNAL OF ECONOMIC ENTOMOLOGY 2010; 103:877-886. [PMID: 20568635 DOI: 10.1603/ec09300] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Over the past three decades, Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), has become a major worldwide pest of many agricultural and horticultural crops. In response, much time, money, and effort have been put into pure and applied research focusing on the biology and control of this pest. Western flower thrips is native to Western North America and widespread in California. High levels of variation in basic biology, pest status, and resistance to insecticides bring into question the specific status of Western flower thrips. We used nuclear-mitochondrial barcoding to compare DNA sequences of nuclear and mitochondrial genes between Western flower thrips populations across California, looking for association between these unlinked loci. Sequences of D2 domain of 28S and cytochrome c oxidase I gene revealed the existence of two distinct but sympatric genetic entities, and we describe a simple polymerase chain reaction-based method for diagnosing these entities. The complete association of these nuclear and mitochondrial loci in areas of sympatry is indicative of reproductive isolation and the existence of two cryptic species, both of which key out to Western flower thrips by using morphological characters. The finding that Western flower thrips is a complex of two species has important implications for past, current, and most importantly future research on these pests.
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Affiliation(s)
- Paul F Rugman-Jones
- Department of Entomology, University of California, Riverside, CA 92521, USA.
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26
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Gene genealogies strongly distorted by weakly interfering mutations in constant environments. Genetics 2009; 184:529-45. [PMID: 19966069 DOI: 10.1534/genetics.109.103556] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Neutral nucleotide diversity does not scale with population size as expected, and this "paradox of variation" is especially severe for animal mitochondria. Adaptive selective sweeps are often proposed as a major cause, but a plausible alternative is selection against large numbers of weakly deleterious mutations subject to Hill-Robertson interference. The mitochondrial genealogies of several species of whale lice (Amphipoda: Cyamus) are consistently too short relative to neutral-theory expectations, and they are also distorted in shape (branch-length proportions) and topology (relative sister-clade sizes). This pattern is not easily explained by adaptive sweeps or demographic history, but it can be reproduced in models of interference among forward and back mutations at large numbers of sites on a nonrecombining chromosome. A coalescent simulation algorithm was used to study this model over a wide range of parameter values. The genealogical distortions are all maximized when the selection coefficients are of critical intermediate sizes, such that Muller's ratchet begins to turn. In this regime, linked neutral nucleotide diversity becomes nearly insensitive to N. Mutations of this size dominate the dynamics even if there are also large numbers of more strongly and more weakly selected sites in the genome. A genealogical perspective on Hill-Robertson interference leads directly to a generalized background-selection model in which the effective population size is progressively reduced going back in time from the present.
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27
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Rosenbaum HC, Pomilla C, Mendez M, Leslie MS, Best PB, Findlay KP, Minton G, Ersts PJ, Collins T, Engel MH, Bonatto SL, Kotze DPGH, Meÿer M, Barendse J, Thornton M, Razafindrakoto Y, Ngouessono S, Vely M, Kiszka J. Population structure of humpback whales from their breeding grounds in the South Atlantic and Indian Oceans. PLoS One 2009; 4:e7318. [PMID: 19812698 PMCID: PMC2754530 DOI: 10.1371/journal.pone.0007318] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Accepted: 08/06/2009] [Indexed: 11/18/2022] Open
Abstract
Although humpback whales are among the best-studied of the large whales, population boundaries in the Southern Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527 samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence, the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed fidelity of migratory destinations, along with other ecological and oceanographic features in the region.
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Affiliation(s)
- Howard C Rosenbaum
- Cetacean Conservation and Research Program, Global Conservation-Marine, Wildlife Conservation Society, Bronx, New York, United States of America.
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28
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Kingston SE, Adams LD, Rosel PE. Testing mitochondrial sequences and anonymous nuclear markers for phylogeny reconstruction in a rapidly radiating group: molecular systematics of the Delphininae (Cetacea: Odontoceti: Delphinidae). BMC Evol Biol 2009; 9:245. [PMID: 19811651 PMCID: PMC2770059 DOI: 10.1186/1471-2148-9-245] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2009] [Accepted: 10/07/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Many molecular phylogenetic analyses rely on DNA sequence data obtained from single or multiple loci, particularly mitochondrial DNA loci. However, phylogenies for taxa that have undergone recent, rapid radiation events often remain unresolved. Alternative methodologies for discerning evolutionary relationships under these conditions are desirable. The dolphin subfamily Delphininae is a group that has likely resulted from a recent and rapid radiation. Despite several efforts, the evolutionary relationships among the species in the subfamily remain unclear. RESULTS Here, we compare a phylogeny estimated using mitochondrial DNA (mtDNA) control region sequences to a multi-locus phylogeny inferred from 418 polymorphic genomic markers obtained from amplified fragment length polymorphism (AFLP) analysis. The two sets of phylogenies are largely incongruent, primarily because the mtDNA tree provides very poor resolving power; very few species' nodes in the tree are supported by bootstrap resampling. The AFLP phylogeny is considerably better resolved and more congruent with relationships inferred from morphological data. Both phylogenies support paraphyly for the genera Stenella and Tursiops. The AFLP data indicate a close relationship between the two spotted dolphin species and recent ancestry between Stenella clymene and S. longirostris. The placement of the Lagenodelphis hosei lineage is ambiguous: phenetic analysis of the AFLP data is consistent with morphological expectations but the phylogenetic analysis is not. CONCLUSION For closely related, recently diverged taxa, a multi-locus genome-wide survey is likely the most comprehensive approach currently available for phylogenetic inference.
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Affiliation(s)
- Sarah E Kingston
- NOAA Fisheries, Southeast Fisheries Science Center, 646 Cajundome Blvd. Suite 234, Lafayette, LA 70506, USA
- University of Maryland, College of Chemical and Life Sciences, Program in Behavior, Ecology, Evolution, and Systematics, Biology-Psychology Building 1204C, College Park, MD 20742, USA
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, 4210 Silver Hill Rd, Suitland, MD 20746, USA
| | - Lara D Adams
- NOAA Fisheries, Southeast Fisheries Science Center, 646 Cajundome Blvd. Suite 234, Lafayette, LA 70506, USA
- National Ocean Service, 219 Fort Johnson Road, Charleston, SC 29412, USA
| | - Patricia E Rosel
- NOAA Fisheries, Southeast Fisheries Science Center, 646 Cajundome Blvd. Suite 234, Lafayette, LA 70506, USA
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Gamble T, Berendzen PB, Bradley Shaffer H, Starkey DE, Simons AM. Species limits and phylogeography of North American cricket frogs (Acris: Hylidae). Mol Phylogenet Evol 2008; 48:112-25. [DOI: 10.1016/j.ympev.2008.03.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 02/22/2008] [Accepted: 03/10/2008] [Indexed: 10/22/2022]
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NARUM S, BANKS M, BEACHAM T, BELLINGER M, CAMPBELL M, DEKONING J, ELZ A, GUTHRIEIII C, KOZFKAY C, MILLER K, MORAN P, PHILLIPS R, SEEB L, SMITH C, WARHEIT K, YOUNG S, GARZA J. Differentiating salmon populations at broad and fine geographical scales with microsatellites and single nucleotide polymorphisms. Mol Ecol 2008; 17:3464-77. [DOI: 10.1111/j.1365-294x.2008.03851.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Parks SE, Clark CW, Tyack PL. Short- and long-term changes in right whale calling behavior: the potential effects of noise on acoustic communication. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2007; 122:3725-31. [PMID: 18247780 DOI: 10.1121/1.2799904] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The impact of anthropogenic noise on marine mammals has been an area of increasing concern over the past two decades. Most low-frequency anthropogenic noise in the ocean comes from commercial shipping which has contributed to an increase in ocean background noise over the past 150 years. The long-term impacts of these changes on marine mammals are not well understood. This paper describes both short- and long-term behavioral changes in calls produced by the endangered North Atlantic right whale (Eubalaena glacialis) and South Atlantic right whale (Eubalaena australis) in the presence of increased low-frequency noise. Right whales produce calls with a higher average fundamental frequency and they call at a lower rate in high noise conditions, possibly in response to masking from low-frequency noise. The long-term changes have occurred within the known lifespan of individual whales, indicating that a behavioral change, rather than selective pressure, has resulted in the observed differences. This study provides evidence of a behavioral change in sound production of right whales that is correlated with increased noise levels and indicates that right whales may shift call frequency to compensate for increased band-limited background noise.
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Affiliation(s)
- Susan E Parks
- Bioacoustics Research Program, Cornell Laboratory of Ornithology, 159 Sapsucker Woods Road, Ithaca, New York 14850, USA.
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Caballero S, Jackson J, Mignucci-Giannoni AA, Barrios-Garrido H, Beltrán-Pedreros S, Montiel-Villalobos MAG, Robertson KM, Baker CS. Molecular systematics of South American dolphins Sotalia: sister taxa determination and phylogenetic relationships, with insights into a multi-locus phylogeny of the Delphinidae. Mol Phylogenet Evol 2007; 46:252-68. [PMID: 18053749 DOI: 10.1016/j.ympev.2007.10.015] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 09/19/2007] [Accepted: 10/17/2007] [Indexed: 11/16/2022]
Abstract
The evolutionary relationships among members of the cetacean family Delphinidae, the dolphins, pilot whales and killer whales, are still not well understood. The genus Sotalia (coastal and riverine South American dolphins) is currently considered a member of the Stenoninae subfamily, along with the genera Steno (rough toothed dolphin) and Sousa (humpbacked dolphin). In recent years, a revision of this classification was proposed based on phylogenetic analysis of the mitochondrial gene cytochrome b, wherein Sousa was included in the Delphininae subfamily, keeping only Steno and Sotalia as members of the Stenoninae subfamily. Here we investigate the phylogenetic placement of Sotalia using two mitochondrial genes, six autosomal introns and four Y chromosome introns, providing a total of 5,196 base pairs (bp) for each taxon in the combined dataset. Sequences from these genomic regions were obtained for 17 delphinid species, including at least one species from each of five or six currently recognized subfamilies plus five odontocete outgroup species. Maximum Parsimony, Maximum Likelihood and Bayesian phylogenetic analysis of independent (each fragment) and combined datasets (mtDNA, nuDNA or mtDNA+nuDNA) showed that Sotalia and Sousa fall within a clade containing other members of Delphininae, exclusive of Steno. Sousa was resolved as the sister taxon to Sotalia according to analysis of the nuDNA dataset but not analysis of the mtDNA or combined mtDNA+nuDNA datasets. Based on the results from our multi-locus analysis, we offer several novel changes to the classification of Delphinidae, some of which are supported by previous morphological and molecular studies.
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Affiliation(s)
- Susana Caballero
- Laboratory of Molecular Ecology and Evolution, School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand.
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Chapman MA, Chang J, Weisman D, Kesseli RV, Burke JM. Universal markers for comparative mapping and phylogenetic analysis in the Asteraceae (Compositae). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2007; 115:747-55. [PMID: 17634914 DOI: 10.1007/s00122-007-0605-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Accepted: 06/30/2007] [Indexed: 05/16/2023]
Abstract
The development of universal markers that can be assayed across taxa, but which are polymorphic within taxa, can facilitate both comparative map-based studies and phylogenetic analyses. Here we describe the development of such markers for use in the Asteraceae, which includes the crops lettuce, sunflower, and safflower as well as dozens of locally important crop and weed species. Using alignments of a conserved orthologous set (COS) of ESTs from lettuce and sunflower and genomic sequences of Arabidopsis, we designed a suite of primer pairs that are conserved across species, but which are predicted to flank introns. We then tested 192 such primer pairs in 8 species from across the family. Of these, 163 produced an amplicon in at least 1 taxon, and 125 amplified in at least half of the taxa surveyed. Thirty-nine amplified in all 8 species. Comparisons amongst sequences within the lettuce and sunflower EST databases indicate that the vast majority of these loci will be polymorphic. As a direct test of the utility of these markers outside the lettuce and sunflower subfamilies, we sequenced a subset of ten loci from a panel of cultivated safflower individuals. All 10 loci proved to be single-locus, and nine of the 10 loci were polymorphic with an average of 12.8 SNPs per kb. Taken together, these loci will provide an initial backbone for comparative genetic analyses within the Asteraceae. Moreover, our results indicate that these loci are phylogenetically informative, and hence can be used to resolve evolutionary relationships between taxa within the family as well as within species.
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Affiliation(s)
- Mark A Chapman
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA.
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Twito T, Weigend S, Blum S, Granevitze Z, Feldman MW, Perl-Treves R, Lavi U, Hillel J. Biodiversity of 20 chicken breeds assessed by SNPs located in gene regions. Cytogenet Genome Res 2007; 117:319-26. [PMID: 17675874 DOI: 10.1159/000103194] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2006] [Accepted: 09/27/2006] [Indexed: 11/19/2022] Open
Abstract
Twenty-five single nucleotide polymorphisms (SNPs) were analyzed in 20 distinct chicken breeds. The SNPs, each located in a different gene and mostly on different chromosomes, were chosen to examine the use of SNPs in or close to genes (g-SNPs), for biodiversity studies. Phylogenetic trees were constructed from these data. When bootstrap values were used as a criterion for the tree repeatability, doubling the number of SNPs from 12 to 25 improved tree repeatability more than doubling the number of individuals per population, from five to ten. Clustering results of these 20 populations, based on the software STRUCTURE, are in agreement with those previously obtained from the analysis of microsatellites. When the number of clusters was similar to the number of populations, affiliation of birds to their original populations was correct (>95%) only when at least the 22 most polymorphic SNP loci (out of 25) were included. When ten populations were clustered into five groups based on STRUCTURE, we used membership coefficient (Q) of the major cluster at each population as an indicator for clustering success level. This value was used to compare between three marker types; microsatellites, SNPs in or close to genes (g-SNPs) and SNPs in random fragments (r-SNPs). In this comparison, the same individuals were used (five to ten birds per population) and the same number of loci (14) used for each of the marker types. The average membership coefficients (Q) of the major cluster for microsatellites, g-SNPs and r-SNPs were 0.85, 0.7, and 0.64, respectively. Analysis based on microsatellites resulted in significantly higher clustering success due to their multi-allelic nature. Nevertheless, SNPs have obvious advantages, and are an efficient and cost-effective genetic tool, providing broader genome coverage and reliable estimates of genetic relatedness.
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Affiliation(s)
- T Twito
- Faculty of Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
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Reeb D, Best PB, Kidson SH. Structure of the integument of southern right whales, Eubalaena australis. Anat Rec (Hoboken) 2007; 290:596-613. [PMID: 17516424 DOI: 10.1002/ar.20535] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Skin (integument) anatomy reflects adaptations to particular environments. It is hypothesized that cetacean (whale) integument will show unique anatomical adaptations to an aquatic environment, particularly regarding differences in temperature, density, and pressure. In this study, the gross and histological structure of the southern right whale integument is described and compared with terrestrial mammals and previous descriptions of mysticete (baleen whale) and odontocete (toothed whale) species. Samples were taken of the integument of 98 free-swimming southern right whales, Eubalaena australis, and examined by both light and electron microscopy. Results show that three epidermal layers are present, with the stratum corneum being parakeratotic in nature. As in bowhead whales, southern right whales possess an acanthotic epidermis and a notably thick hypodermis, with epidermal rods and extensive papillomatosis. However, unlike bowhead whales, southern right whales possess an uninterrupted hypodermal layer. Surprisingly, the integument of balaenids (right and bowhead mysticetes) in general is more like that of odontocetes than that of the more closely related balaenopterids (rorqual mysticetes). Similarities to odontocetes were found specifically in the collagen fibers in a fat-free zone of the reticular dermal layer and the elastic fibers in the dermal and hypodermal layers. Callosities, a distinctive feature of this genus, have a slightly thicker stratum corneum and are usually associated with hairs that have innervated and vascularized follicles. These hairs may function as vibrissae, thus aiding in aquatic foraging by allowing rapid detection of changes in prey density. Although the thick insulatory integument makes right whales bulky and slow-moving, it is an adaptation for living in cold water. Epidermal thickness, presence of epidermal rods, and callosities may act as barriers against mechanical injury from bodily contact with conspecifics or hard surfaces in the environment (e.g., rocks, ice).
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Affiliation(s)
- Desray Reeb
- Mammal Research Institute, University of Pretoria, Cape Town, South Africa.
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Galewski T, Tilak MK, Sanchez S, Chevret P, Paradis E, Douzery EJP. The evolutionary radiation of Arvicolinae rodents (voles and lemmings): relative contribution of nuclear and mitochondrial DNA phylogenies. BMC Evol Biol 2006; 6:80. [PMID: 17029633 PMCID: PMC1618403 DOI: 10.1186/1471-2148-6-80] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Accepted: 10/09/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mitochondrial and nuclear genes have generally been employed for different purposes in molecular systematics, the former to resolve relationships within recently evolved groups and the latter to investigate phylogenies at a deeper level. In the case of rapid and recent evolutionary radiations, mitochondrial genes like cytochrome b (CYB) are often inefficient for resolving phylogenetic relationships. One of the best examples is illustrated by Arvicolinae rodents (Rodentia; Muridae), the most impressive mammalian radiation of the Northern Hemisphere which produced voles, lemmings and muskrats. Here, we compare the relative contribution of a nuclear marker--the exon 10 of the growth hormone receptor (GHR) gene--to the one of the mitochondrial CYB for inferring phylogenetic relationships among the major lineages of arvicoline rodents. RESULTS The analysis of GHR sequences improves the overall resolution of the Arvicolinae phylogeny. Our results show that the Caucasian long-clawed vole (Prometheomys schaposnikowi) is one of the basalmost arvicolines, and confirm that true lemmings (Lemmus) and collared lemmings (Dicrostonyx) are not closely related as suggested by morphology. Red-backed voles (Myodini) are found as the sister-group of a clade encompassing water vole (Arvicola), snow vole (Chionomys), and meadow voles (Microtus and allies). Within the latter, no support is recovered for the generic recognition of Blanfordimys, Lasiopodomys, Neodon, and Phaiomys as suggested by morphology. Comparisons of parameter estimates for branch lengths, base composition, among sites rate heterogeneity, and GTR relative substitution rates indicate that CYB sequences consistently exhibit more heterogeneity among codon positions than GHR. By analyzing the contribution of each codon position to node resolution, we show that the apparent higher efficiency of GHR is due to their third positions. Although we focus on speciation events spanning the last 10 million years (Myr), CYB sequences display highly saturated codon positions contrary to the nuclear exon. Lastly, variable length bootstrap predicts a significant increase in resolution of arvicoline phylogeny through the sequencing of nuclear data in an order of magnitude three to five times greater than the size of GHR exon 10. CONCLUSION Our survey provides a first resolved gene tree for Arvicolinae. The comparison of CYB and GHR phylogenetic efficiency supports recent assertions that nuclear genes are useful for resolving relationships of recently evolved animals. The superiority of nuclear exons may reside both in (i) less heterogeneity among sites, and (ii) the presence of highly informative sites in third codon positions, that evolve rapidly enough to accumulate synapomorphies, but slow enough to avoid substitutional saturation.
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Affiliation(s)
- Thomas Galewski
- Laboratoire de Paléontologie, Phylogénie et Paléobiologie--CC064, Institut des Sciences de l'Evolution UMR 5554/CNRS, Université Montpellier II, France.
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Kaliszewska ZA, Seger J, Rowntree VJ, Barco SG, Benegas R, Best PB, Brown MW, Brownell RL, Carribero A, Harcourt R, Knowlton AR, Marshall-Tilas K, Patenaude NJ, Rivarola M, Schaeff CM, Sironi M, Smith WA, Yamada TK. Population histories of right whales (Cetacea: Eubalaena) inferred from mitochondrial sequence diversities and divergences of their whale lice (Amphipoda: Cyamus). Mol Ecol 2006; 14:3439-56. [PMID: 16156814 DOI: 10.1111/j.1365-294x.2005.02664.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Right whales carry large populations of three 'whale lice' (Cyamus ovalis, Cyamus gracilis, Cyamus erraticus) that have no other hosts. We used sequence variation in the mitochondrial COI gene to ask (i) whether cyamid population structures might reveal associations among right whale individuals and subpopulations, (ii) whether the divergences of the three nominally conspecific cyamid species on North Atlantic, North Pacific, and southern right whales (Eubalaena glacialis, Eubalaena japonica, Eubalaena australis) might indicate their times of separation, and (iii) whether the shapes of cyamid gene trees might contain information about changes in the population sizes of right whales. We found high levels of nucleotide diversity but almost no population structure within oceans, indicating large effective population sizes and high rates of transfer between whales and subpopulations. North Atlantic and Southern Ocean populations of all three species are reciprocally monophyletic, and North Pacific C. erraticus is well separated from North Atlantic and southern C. erraticus. Mitochondrial clock calibrations suggest that these divergences occurred around 6 million years ago (Ma), and that the Eubalaena mitochondrial clock is very slow. North Pacific C. ovalis forms a clade inside the southern C. ovalis gene tree, implying that at least one right whale has crossed the equator in the Pacific Ocean within the last 1-2 million years (Myr). Low-frequency polymorphisms are more common than expected under neutrality for populations of constant size, but there is no obvious signal of rapid, interspecifically congruent expansion of the kind that would be expected if North Atlantic or southern right whales had experienced a prolonged population bottleneck within the last 0.5 Myr.
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Affiliation(s)
- Zofia A Kaliszewska
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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Pringle A, Baker DM, Platt JL, Wares JP, Latgé JP, Taylor JW. CRYPTIC SPECIATION IN THE COSMOPOLITAN AND CLONAL HUMAN PATHOGENIC FUNGUS ASPERGILLUS FUMIGATUS. Evolution 2005. [DOI: 10.1111/j.0014-3820.2005.tb01059.x] [Citation(s) in RCA: 208] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Johnson JA, Watson RT, Mindell DP. Prioritizing species conservation: does the Cape Verde kite exist? Proc Biol Sci 2005; 272:1365-71. [PMID: 16006325 PMCID: PMC1560339 DOI: 10.1098/rspb.2005.3098] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Cape Verde kite (Milvus milvus fasciicauda) is considered to be one of the rarest birds of prey in the world and at significant risk of extinction. For this reason there is great interest in both the taxonomic and the population status of this group. To help resolve its taxonomic status, we provide phylogenetic analyses based on three mitochondrial genes for a sampling of kites in the genus Milvus, including a broad geographical sampling of black kites (Milvus migrans), red kites (Milvus milvus), Cape Verde kite museum specimens collected between 1897 and 1924, and five kites trapped on the Cape Verde Islands during August 2002. We found that the historical Cape Verde kites, including the type specimen, were non-monophyletic and scattered within a larger red kite clade. The recently trapped kites from the Cape Verde Islands were all phylogenetically diagnosed as black kites. Our findings suggest that the traditional Cape Verde kite is not a distinctive evolutionary unit, and the case for species status, as recently suggested by others, is not supported. We do find support for recognition of at least one clade of yellow-billed kites, traditionally considered as a black kite subspecies, as a distinctive phylogenetic species.
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Affiliation(s)
- Jeff A Johnson
- The Peregrine Fund, 5668 West Flying Hawk Lane, Boise, ID 83709, USA.
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Pringle A, Baker DM, Platt JL, Wares JP, Latgé JP, Taylor JW. CRYPTIC SPECIATION IN THE COSMOPOLITAN AND CLONAL HUMAN PATHOGENIC FUNGUS ASPERGILLUS FUMIGATUS. Evolution 2005. [DOI: 10.1554/04-241.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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