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Alvarado-Cerón V, Muñiz-Castillo AI, León-Pech MG, Prada C, Arias-González JE. A decade of population genetics studies of scleractinian corals: A systematic review. MARINE ENVIRONMENTAL RESEARCH 2023; 183:105781. [PMID: 36371949 DOI: 10.1016/j.marenvres.2022.105781] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 10/11/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
Coral reefs are the most diverse marine ecosystems. However, coral cover has decreased worldwide due to natural disturbances, climate change, and local anthropogenic drivers. In recent decades, various genetic methods and molecular markers have been developed to assess genetic diversity, structure, and connectivity in different coral species to determine the vulnerability of their populations. This review aims to identify population genetic studies of scleractinian corals in the last decade (2010-2020), and the techniques and molecular markers used. Bibliometric analysis was conducted to identify journals and authors working in this field. We then calculated the number of genetic studies by species and ecoregion based on data obtained from 178 studies found in Scopus and Web of Science. Coral Reefs and Molecular Ecology were the main journals published population genetics studies, and microsatellites are the most widely used molecular markers. The Caribbean, Australian Barrier Reef, and South Kuroshio in Japan are among the ecoregions with the most population genetics data. In contrast, we found limited information about the Coral Triangle, a region with the highest biodiversity and key to coral reef conservation. Notably, only 117 (out of 1500 described) scleractinian coral species have genetic studies. This review emphasizes which coral species have been studied and highlights remaining gaps and locations where such data is critical for coral conservation.
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Affiliation(s)
- Viridiana Alvarado-Cerón
- Departamento de Recursos del Mar, Centro de Investigación y de Estudios Avanzados del I.P.N., Unidad Mérida. Km. 6 Antigua carretera a Progreso, Cordemex, 97310, Mérida, Yucatán, Mexico.
| | - Aarón Israel Muñiz-Castillo
- Departamento de Recursos del Mar, Centro de Investigación y de Estudios Avanzados del I.P.N., Unidad Mérida. Km. 6 Antigua carretera a Progreso, Cordemex, 97310, Mérida, Yucatán, Mexico.
| | - María Geovana León-Pech
- Department of Biological Science, University of Rhode Island, 120 Flag Road, Kingston, RI, 02881, USA.
| | - Carlos Prada
- Department of Biological Science, University of Rhode Island, 120 Flag Road, Kingston, RI, 02881, USA.
| | - Jesús Ernesto Arias-González
- Departamento de Recursos del Mar, Centro de Investigación y de Estudios Avanzados del I.P.N., Unidad Mérida. Km. 6 Antigua carretera a Progreso, Cordemex, 97310, Mérida, Yucatán, Mexico.
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2
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Thomas L, Underwood JN, Rose NH, Fuller ZL, Richards ZT, Dugal L, Grimaldi CM, Cooke IR, Palumbi SR, Gilmour JP. Spatially varying selection between habitats drives physiological shifts and local adaptation in a broadcast spawning coral on a remote atoll in Western Australia. SCIENCE ADVANCES 2022; 8:eabl9185. [PMID: 35476443 PMCID: PMC9045720 DOI: 10.1126/sciadv.abl9185] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
At the Rowley Shoals in Western Australia, the prominent reef flat becomes exposed on low tide and the stagnant water in the shallow atoll lagoons heats up, creating a natural laboratory for characterizing the mechanisms of coral resilience to climate change. To explore these mechanisms in the reef coral Acropora tenuis, we collected samples from lagoon and reef slope habitats and combined whole-genome sequencing, ITS2 metabarcoding, experimental heat stress, and transcriptomics. Despite high gene flow across the atoll, we identified clear shifts in allele frequencies between habitats at relatively small linked genomic islands. Common garden heat stress assays showed corals from the lagoon to be more resistant to bleaching, and RNA sequencing revealed marked differences in baseline levels of gene expression between habitats. Our results provide new insight into the complex mechanisms of coral resilience to climate change and highlight the potential for spatially varying selection across complex coral reef seascapes to drive pronounced ecological divergence in climate-related traits.
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Affiliation(s)
- Luke Thomas
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre, Crawley, Australia
- UWA Oceans Institute, Oceans Graduate School, The University of Western Australia, Crawley, Australia
- Corresponding author.
| | - Jim N. Underwood
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre, Crawley, Australia
| | - Noah H. Rose
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | - Zachary L. Fuller
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Zoe T. Richards
- Coral Conservation and Research Group, School of Molecular and Life Sciences, Curtin University, Perth, Australia
- Collections and Research, Western Australian Museum, Welshpool, Australia
| | - Laurence Dugal
- UWA Oceans Institute, Oceans Graduate School, The University of Western Australia, Crawley, Australia
| | - Camille M. Grimaldi
- UWA Oceans Institute, Oceans Graduate School, The University of Western Australia, Crawley, Australia
| | - Ira R. Cooke
- Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, Townsville, Queensland, Australia
| | - Stephen R. Palumbi
- Hopkins Marine Station, Biology Department, Stanford University, Pacific Grove, CA, USA
| | - James P. Gilmour
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre, Crawley, Australia
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3
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Stankiewicz KH, Vasquez Kuntz KL, Baums IB. The impact of estimator choice: Disagreement in clustering solutions across K estimators for Bayesian analysis of population genetic structure across a wide range of empirical data sets. Mol Ecol Resour 2021; 22:1135-1148. [PMID: 34597471 DOI: 10.1111/1755-0998.13522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 08/21/2021] [Accepted: 09/07/2021] [Indexed: 11/29/2022]
Abstract
The software program STRUCTURE is one of the most cited tools for determining population structure. To infer the optimal number of clusters from STRUCTURE output, the ΔK method is often applied. However, a recent study relying on simulated microsatellite data suggested that this method has a downward bias in its estimation of K and is sensitive to uneven sampling. If this finding holds for empirical data sets, conclusions about the scale of gene flow may have to be revised for a large number of studies. To determine the impact of method choice, we applied recently described estimators of K to re-estimate genetic structure in 41 empirical microsatellite data sets; 15 from a broad range of taxa and 26 from one phylogenetic group, coral. We compared alternative estimates of K (Puechmaille statistics) with traditional (ΔK and posterior probability) estimates and found widespread disagreement of estimators across data sets. Thus, one estimator alone is insufficient for determining the optimal number of clusters; this was regardless of study organism or evenness of sampling scheme. Subsequent analysis of molecular variance (AMOVA) did not necessarily clarify which clustering solution was best. To better infer population structure, we suggest a combination of visual inspection of STRUCTURE plots and calculation of the alternative estimators at various thresholds in addition to ΔK. Disagreement between traditional and recent estimators may have important biological implications, such as previously unrecognized population structure, as was the case for many studies reanalysed here.
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Affiliation(s)
- Kathryn H Stankiewicz
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Kate L Vasquez Kuntz
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
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4
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Donati GFA, Zemp N, Manel S, Poirier M, Claverie T, Ferraton F, Gaboriau T, Govinden R, Hagen O, Ibrahim S, Mouillot D, Leblond J, Julius P, Velez L, Zareer I, Ziyad A, Leprieur F, Albouy C, Pellissier L. Species ecology explains the spatial components of genetic diversity in tropical reef fishes. Proc Biol Sci 2021; 288:20211574. [PMID: 34583586 PMCID: PMC8479362 DOI: 10.1098/rspb.2021.1574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/03/2021] [Indexed: 11/12/2022] Open
Abstract
Generating genomic data for 19 tropical reef fish species of the Western Indian Ocean, we investigate how species ecology influences genetic diversity patterns from local to regional scales. We distinguish between the α, β and γ components of genetic diversity, which we subsequently link to six ecological traits. We find that the α and γ components of genetic diversity are strongly correlated so that species with a high total regional genetic diversity display systematically high local diversity. The α and γ diversity components are negatively associated with species abundance recorded using underwater visual surveys and positively associated with body size. Pelagic larval duration is found to be negatively related to genetic β diversity supporting its role as a dispersal trait in marine fishes. Deviation from the neutral theory of molecular evolution motivates further effort to understand the processes shaping genetic diversity and ultimately the diversification of the exceptional diversity of tropical reef fishes.
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Affiliation(s)
- Giulia Francesca Azzurra Donati
- Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, CH8092 Zürich, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH8903 Birmensdorf, Switzerland
| | - Niklaus Zemp
- Genetic Diversity Centre (GDC), ETH Zürich, CH8092 Zürich, Switzerland
| | - Stéphanie Manel
- CEFE, Univ Montpellier, CNRS EPHE-PSL University, IRD, Montpellier, France
| | - Maude Poirier
- Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, CH8092 Zürich, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH8903 Birmensdorf, Switzerland
| | - Thomas Claverie
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier 34095, France
- Centre Universitaire de formation et de recherche de Mayotte, Dembeni 97660, France
| | - Franck Ferraton
- Centre National de la Recherche Scientifique (CNRS), UMR 248 MARBEC, Montpellier, France
| | - Théo Gaboriau
- Department of Computational Biology, University of Lausanne, 1015 Lausanne, Switzerland
- Swiss Institute of Bioinformatics, Quartier Sorge, 1015 Lausanne, Switzerland
| | | | - Oskar Hagen
- Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, CH8092 Zürich, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH8903 Birmensdorf, Switzerland
| | - Shameel Ibrahim
- Maldives Whale Shark Research Programme, Popeshead Court Offices, Peter Lane, York, Yorkshire Y01 8SU, UK
| | - David Mouillot
- CEFE, Univ Montpellier, CNRS EPHE-PSL University, IRD, Montpellier, France
- Institut Universitaire de France, Paris, France
| | - Julien Leblond
- Wildlife Conservation Society, Madagascar Program, Antananarivo, Madagascar
| | | | - Laure Velez
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier 34095, France
| | - Irthisham Zareer
- Maldives Whale Shark Research Programme, Popeshead Court Offices, Peter Lane, York, Yorkshire Y01 8SU, UK
| | - Adam Ziyad
- Ministry of Fisheries and Agriculture, Malé, Republic of Maldives
| | - Fabien Leprieur
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier 34095, France
- Institut Universitaire de France, Paris, France
| | - Camille Albouy
- IFREMER, Unité Écologie et Modèles pour l'Halieutique, rue de l'Ile d'Yeu, BP21105, 44311 Nantes cedex 3, France
| | - Loïc Pellissier
- Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, CH8092 Zürich, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH8903 Birmensdorf, Switzerland
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5
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Zayasu Y, Satoh N, Shinzato C. Genetic diversity of farmed and wild populations of the reef-building coral, Acropora tenuis. Restor Ecol 2018. [DOI: 10.1111/rec.12687] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Yuna Zayasu
- Marine Genomics Unit; Okinawa Institute of Science and Technology Graduate University; 1919-1 Tancha, Onna-son, Okinawa, 904-0495 Japan
| | - Noriyuki Satoh
- Marine Genomics Unit; Okinawa Institute of Science and Technology Graduate University; 1919-1 Tancha, Onna-son, Okinawa, 904-0495 Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute; The University of Tokyo; Chiba, 277-8564 Japan
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6
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Devlin-Durante MK, Baums IB. Genome-wide survey of single-nucleotide polymorphisms reveals fine-scale population structure and signs of selection in the threatened Caribbean elkhorn coral, Acropora palmata. PeerJ 2017; 5:e4077. [PMID: 29181279 PMCID: PMC5701561 DOI: 10.7717/peerj.4077] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 10/31/2017] [Indexed: 12/18/2022] Open
Abstract
The advent of next-generation sequencing tools has made it possible to conduct fine-scale surveys of population differentiation and genome-wide scans for signatures of selection in non-model organisms. Such surveys are of particular importance in sharply declining coral species, since knowledge of population boundaries and signs of local adaptation can inform restoration and conservation efforts. Here, we use genome-wide surveys of single-nucleotide polymorphisms in the threatened Caribbean elkhorn coral, Acropora palmata, to reveal fine-scale population structure and infer the major barrier to gene flow that separates the eastern and western Caribbean populations between the Bahamas and Puerto Rico. The exact location of this break had been subject to discussion because two previous studies based on microsatellite data had come to differing conclusions. We investigate this contradiction by analyzing an extended set of 11 microsatellite markers including the five previously employed and discovered that one of the original microsatellite loci is apparently under selection. Exclusion of this locus reconciles the results from the SNP and the microsatellite datasets. Scans for outlier loci in the SNP data detected 13 candidate loci under positive selection, however there was no correlation between available environmental parameters and genetic distance. Together, these results suggest that reef restoration efforts should use local sources and utilize existing functional variation among geographic regions in ex situ crossing experiments to improve stress resistance of this species.
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Affiliation(s)
- Meghann K Devlin-Durante
- Department of Biology, Pennsylvania State University, University Park, PA, United States of America
| | - Iliana B Baums
- Department of Biology, Pennsylvania State University, University Park, PA, United States of America
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7
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Devlin‐Durante MK, Miller MW, Precht WF, Baums IB, Carne L, Smith TB, Banaszak AT, Greer L, Irwin A, Fogarty ND, Williams DE. How old are you? Genet age estimates in a clonal animal. Mol Ecol 2016; 25:5628-5646. [DOI: 10.1111/mec.13865] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 09/12/2016] [Accepted: 09/19/2016] [Indexed: 01/10/2023]
Affiliation(s)
- M. K. Devlin‐Durante
- Department of Biology The Pennsylvania State University 208 Mueller Lab University Park PA 16802 USA
| | - M. W. Miller
- Southeast Fisheries Science Center National Marine Fisheries Service 75 Virginia Beach Dr. Miami FL 33149 USA
| | - W. F. Precht
- Marine & Coastal Programs Dial Cordy & Associates 90 Osceola Ave Jacksonville Beach FL 32250 USA
| | - I. B. Baums
- Department of Biology The Pennsylvania State University 208 Mueller Lab University Park PA 16802 USA
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8
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Cryptic genetic divergence within threatened species of Acropora coral from the Indian and Pacific Oceans. CONSERV GENET 2016. [DOI: 10.1007/s10592-015-0807-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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9
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Gu Q, Zhang M, Zhou C, Zhu G, Dong J, Gao Y, Chen J, Chen P. Analysis of genetic diversity and population structure of Bellamya quadrata from lakes of middle and lower Yangtze River. Genetica 2015; 143:545-54. [PMID: 26092369 DOI: 10.1007/s10709-015-9852-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 06/15/2015] [Indexed: 11/24/2022]
Abstract
As an endemic species of freshwater gastropods in China, Bellamya quadrata plays an important role in ecosystem service provision and commercial importance. However, the species is overharvested and its natural habitats are under severe threat due to fragmentation and loss. To estimate the genetic diversity and population structure of B. quadrata, 285 individuals from eight lake populations across middle and lower Yangtze River were sampled. Seven microsatellite loci were genotyped. Our results showed that (i) the genetic diversity of B. quadrata was high in most of the studied populations, yet effective population sizes appear to be rather small in some populations; (ii) low levels of genetic differentiation exists among populations but gene flow was generally high; (iii) no clear geographic or genetic structure was observed in the studied region, implying mechanisms (zoochoric dispersal and anthropogenic translocations) that enhance dispersal and gene flow have promoted population connectivity. However, the comparatively high genetic diversity of B. quadrata could be attributed to a lag phase, suggesting that the genetic diversity of this species may be lost in the future and the priorities for conservation of B. quadrata are necessary.
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Affiliation(s)
- Qianhong Gu
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, 453007, People's Republic of China,
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10
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Mège P, Schizas NV, Reyes JG, Hrbek T. Genetic seascape of the threatened Caribbean elkhorn coral, Acropora palmata, on the Puerto Rico Shelf. MARINE ECOLOGY (BERLIN, GERMANY) 2015; 36:195-209. [PMID: 26085704 PMCID: PMC4465847 DOI: 10.1111/maec.12135] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
It has been proposed that the elkhorn coral, Acropora palmata, is genetically separated into two distinct provinces in the Caribbean, an Eastern and a Western population admixing in western Puerto Rico and around the Mona Passage. In this study, the genetic structure of A. palmata sampled at 11 Puerto Rican localities and localities from Curaçao, the Bahamas and Guadeloupe were examined. Analyses using five microsatellite markers showed that 75% of sampled colonies had unique genotypes, the rest being clone mates. Genetic diversity among genets was high (HE = 0.761) and consistent across localities (0.685 to 0.844). FST ranged from -0.011 to 0.047 supporting low but significant genetic differentiation between localities within the previously reported Eastern and Western genetic provinces. Plots of genetic per geographic distances and significant Mantel tests supported isolation-by-distance (IBD) within Puerto Rico. Analysis with the software Structure favored a scenario with weak differentiation between two populations, assigning eastern Puerto Rican locations (Fajardo and Culebra), Guadeloupe and Curaçao to the Caribbean Eastern population and western Puerto Rican locations (west of Vega Baja and Ponce), Mona and the Bahamas to the Caribbean Western population. Vieques and San Juan area harbored admixed profiles. Standardized FSTs per 1,000 km unit further supported higher differentiation between localities belonging to different Structure populations, with IBD being stronger within Puerto Rico than on larger regional scales. This stronger genetic transition seems to separate localities between putative Eastern and Western provinces in the eastern Puerto Rican region, not around the Mona Passage.
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Affiliation(s)
- Pascal Mège
- Department of Biology, University of Puerto Rico-Río Piedras, San Juan, Puerto Rico
| | - Nikolaos V. Schizas
- Department of Marine Sciences, University of Puerto Rico-Mayagüez, Call Box 9000, Mayagüez, Puerto Rico
| | - Joselyd García Reyes
- Department of Marine Sciences, University of Puerto Rico-Mayagüez, Call Box 9000, Mayagüez, Puerto Rico
| | - Tomas Hrbek
- Department of Biology, University of Puerto Rico-Río Piedras, San Juan, Puerto Rico
- Laboratório de Evolução e Genética Animal, Universidade Federal do Amazonas, Manaus, Brazil
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11
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Schweinsberg M, Weiss LC, Striewski S, Tollrian R, Lampert KP. More than one genotype: how common is intracolonial genetic variability in scleractinian corals? Mol Ecol 2015; 24:2673-85. [DOI: 10.1111/mec.13200] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 03/26/2015] [Accepted: 04/02/2015] [Indexed: 01/01/2023]
Affiliation(s)
- Maximilian Schweinsberg
- Department of Animal Ecology, Evolution and Biodiversity; University of Bochum; 44780 Bochum Germany
| | - Linda C. Weiss
- Department of Animal Ecology, Evolution and Biodiversity; University of Bochum; 44780 Bochum Germany
| | - Sebastian Striewski
- Department of Animal Ecology, Evolution and Biodiversity; University of Bochum; 44780 Bochum Germany
| | - Ralph Tollrian
- Department of Animal Ecology, Evolution and Biodiversity; University of Bochum; 44780 Bochum Germany
| | - Kathrin P. Lampert
- Department of Animal Ecology, Evolution and Biodiversity; University of Bochum; 44780 Bochum Germany
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12
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Engler JO, Balkenhol N, Filz KJ, Habel JC, Rödder D. Comparative landscape genetics of three closely related sympatric Hesperid butterflies with diverging ecological traits. PLoS One 2014; 9:e106526. [PMID: 25184414 PMCID: PMC4153614 DOI: 10.1371/journal.pone.0106526] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Accepted: 08/07/2014] [Indexed: 12/02/2022] Open
Abstract
To understand how landscape characteristics affect gene flow in species with diverging ecological traits, it is important to analyze taxonomically related sympatric species in the same landscape using identical methods. Here, we present such a comparative landscape genetic study involving three closely related Hesperid butterflies of the genus Thymelicus that represent a gradient of diverging ecological traits. We analyzed landscape effects on their gene flow by deriving inter-population connectivity estimates based on different species distribution models (SDMs), which were calculated from multiple landscape parameters. We then used SDM output maps to calculate circuit-theoretic connectivity estimates and statistically compared these estimates to actual genetic differentiation in each species. We based our inferences on two different analytical methods and two metrics of genetic differentiation. Results indicate that land use patterns influence population connectivity in the least mobile specialist T. acteon. In contrast, populations of the highly mobile generalist T. lineola were panmictic, lacking any landscape related effect on genetic differentiation. In the species with ecological traits in between those of the congeners, T. sylvestris, climate has a strong impact on inter-population connectivity. However, the relative importance of different landscape factors for connectivity varies when using different metrics of genetic differentiation in this species. Our results show that closely related species representing a gradient of ecological traits also show genetic structures and landscape genetic relationships that gradually change from a geographical macro- to micro-scale. Thus, the type and magnitude of landscape effects on gene flow can differ strongly even among closely related species inhabiting the same landscape, and depend on their relative degree of specialization. In addition, the use of different genetic differentiation metrics makes it possible to detect recent changes in the relative importance of landscape factors affecting gene flow, which likely change as a result of contemporary habitat alterations.
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Affiliation(s)
- Jan O. Engler
- Zoological Research Museum Alexander Koenig, Bonn, Germany
- Department of Wildlife Sciences, University of Göttingen, Göttingen, Germany
- * E-mail:
| | - Niko Balkenhol
- Department of Wildlife Sciences, University of Göttingen, Göttingen, Germany
| | - Katharina J. Filz
- Department of Biogeography, Trier University, Trier, Germany
- Museum of Natural History Dortmund, Dortmund, Germany
| | - Jan C. Habel
- Department of Ecology and Ecosystemmanagement, Technical University Munich, Freising-Weihenstephan, Germany
| | - Dennis Rödder
- Zoological Research Museum Alexander Koenig, Bonn, Germany
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13
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Richards ZT, Miller DJ, Wallace CC. Molecular phylogenetics of geographically restricted Acropora species: implications for threatened species conservation. Mol Phylogenet Evol 2013; 69:837-51. [PMID: 23850500 DOI: 10.1016/j.ympev.2013.06.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 06/18/2013] [Accepted: 06/27/2013] [Indexed: 10/26/2022]
Abstract
To better understand the underlying causes of rarity and extinction risk in Acropora (staghorn coral), we contrast the minimum divergence ages and nucleotide diversity of an array of species with different range sizes and levels of threat. Time-calibrated Bayesian analyses based upon concatenated nuclear and mitochondrial sequence data implied contemporary range size and vulnerability are linked to species age. However, contrary to previous hypotheses that suggest geographically restricted Acropora species evolved in the Plio-Pleistocene, the molecular phylogeny depicts some Indo-Australian species have greater antiquity, diverging in the Miocene. Species age is not related to range size as a simple positive linear function and interpreting the precise tempo of evolution in this genus is greatly complicated by morphological homoplasy and a sparse fossil record. Our phylogenetic reconstructions provide new examples of how morphology conceals cryptic evolutionary relationships in this keystone genus, and offers limited support for the species groupings currently used in Acropora systematics. We hypothesize that in addition to age, other mechanisms (such as a reticulate ancestry) delimit the contemporary range of some Acropora species, as evidenced by the complex patterns of allele sharing and paraphyly we uncover. Overall, both new and ancient evolutionary information may be lost if geographically restricted and threatened Acropora species are forced to extinction. In order to protect coral biodiversity and resolve the evolutionary history of staghorn coral, further analyses based on comprehensive and heterogeneous morphological and molecular data utilizing reticulate models of evolution are needed.
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Affiliation(s)
- Z T Richards
- Aquatic Zoology, Western Australian Museum, 49 Kew Street, Welshpool, WA 6106, Australia.
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