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Alves F, Banks SC, Edworthy M, Stojanovic D, Langmore NE, Heinsohn R. Using conservation genetics to prioritise management options for an endangered songbird. Heredity (Edinb) 2023; 130:289-301. [PMID: 37016134 PMCID: PMC10162965 DOI: 10.1038/s41437-023-00609-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 03/06/2023] [Accepted: 03/06/2023] [Indexed: 04/06/2023] Open
Abstract
Genetic data can be highly informative for answering questions relevant to practical conservation efforts, but remain one of the most neglected aspects of species recovery plans. Framing genetic questions with reference to practical and tractable conservation objectives can help bypass this limitation of the application of genetics in conservation. Using a single-nucleotide polymorphism dataset from reduced-representation sequencing (DArTSeq), we conducted a genetic assessment of remnant populations of the endangered forty-spotted pardalote (Pardalotus quadragintus), a songbird endemic to Tasmania, Australia. Our objectives were to inform strategies for the conservation of genetic diversity in the species and estimate effective population sizes and patterns of inter-population movement to identify management units relevant to population conservation and habitat restoration. We show population genetic structure and identify two small populations on mainland Tasmania as 'satellites' of larger Bruny Island populations connected by migration. Our data identify management units for conservation objectives relating to genetic diversity and habitat restoration. Although our results do not indicate the immediate need to genetically manage populations, the small effective population sizes we estimated for some populations indicate that they are vulnerable to genetic drift, highlighting the urgent need to implement habitat restoration to increase population size and to conduct genetic monitoring. We discuss how our genetic assessment can be used to inform management interventions for the forty-spotted pardalote and show that by assessing contemporary genetic aspects, valuable information for conservation planning and decision-making can be produced to guide actions that account for genetic diversity and increase chances of recovery in species of conservation concern.
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Affiliation(s)
- Fernanda Alves
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, ACT, Australia.
- Fenner School of Environment and Society, Australian National University, Canberra, ACT, Australia.
| | - Sam C Banks
- Research Institute for the Environment and Livelihoods, College of Engineering, IT and the Environment, Charles Darwin University, Darwin, NT, Australia
| | - Max Edworthy
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Dejan Stojanovic
- Fenner School of Environment and Society, Australian National University, Canberra, ACT, Australia
| | - Naomi E Langmore
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Robert Heinsohn
- Fenner School of Environment and Society, Australian National University, Canberra, ACT, Australia
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2
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Cossu P, Mura L, Dedola GL, Lai T, Sanna D, Scarpa F, Azzena I, Fois N, Casu M. Detection of Genetic Patterns in Endangered Marine Species Is Affected by Small Sample Sizes. Animals (Basel) 2022; 12:ani12202763. [PMID: 36290149 PMCID: PMC9597844 DOI: 10.3390/ani12202763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/05/2022] Open
Abstract
Knowledge of Genetic diversity and its spatial distribution is crucial to improve conservation plans for endangered species. Genetic tools help ensure species' long-term persistence by unraveling connectivity patterns and evolutionary trajectories of populations. Here, microsatellite genotypes of individuals from populations of Patella ferruginea are used to assess the effect of sample size on metrics of within-and between-population genetic diversity by combining empirical and simulated data. Within-population metrics are slightly to moderately affected by small sample size, albeit the magnitude of the bias is proportional to the effective population size and gene flow. The power of detecting genetic differentiation among populations increases with sample size, albeit the gain of increasing the number of sampled individuals tends to be negligible between 30 and 50. Our results line up with those of previous studies and highlight that small sample sizes are not always a hindrance to investigating genetic patterns in endangered marine species. Caution is needed in interpreting genetic patterns based on small sample sizes when the observed genetic differentiation is weak. This study also highlights the importance of carrying out genetic monitoring in seemingly well-preserved but potentially isolated populations.
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Affiliation(s)
- Piero Cossu
- Department of Sciences for Nature and Environmental Resources, University of Sassari, 07100 Sassari, Italy
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy
- Correspondence: ; Tel.: +39-079-2280924
| | - Laura Mura
- Dipartimento per la Ricerca nelle Produzioni Animali, Agris Sardegna, 07040 Olmedo, Italy
| | - Gian Luca Dedola
- Department of Sciences for Nature and Environmental Resources, University of Sassari, 07100 Sassari, Italy
| | - Tiziana Lai
- Department of Sciences for Nature and Environmental Resources, University of Sassari, 07100 Sassari, Italy
| | - Daria Sanna
- Department of Sciences for Nature and Environmental Resources, University of Sassari, 07100 Sassari, Italy
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy
| | - Fabio Scarpa
- Department of Sciences for Nature and Environmental Resources, University of Sassari, 07100 Sassari, Italy
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy
| | - Ilenia Azzena
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy
| | - Nicola Fois
- Dipartimento per la Ricerca nelle Produzioni Animali, Agris Sardegna, 07040 Olmedo, Italy
| | - Marco Casu
- Department of Sciences for Nature and Environmental Resources, University of Sassari, 07100 Sassari, Italy
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy
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3
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Willi Y, Kristensen TN, Sgrò CM, Weeks AR, Ørsted M, Hoffmann AA. Conservation genetics as a management tool: The five best-supported paradigms to assist the management of threatened species. Proc Natl Acad Sci U S A 2022; 119:e2105076119. [PMID: 34930821 PMCID: PMC8740573 DOI: 10.1073/pnas.2105076119] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
About 50 y ago, Crow and Kimura [An Introduction to Population Genetics Theory (1970)] and Ohta and Kimura [Genet. Res. 22, 201-204 (1973)] laid the foundations of conservation genetics by predicting the relationship between population size and genetic marker diversity. This work sparked an enormous research effort investigating the importance of population dynamics, in particular small population size, for population mean performance, population viability, and evolutionary potential. In light of a recent perspective [J. C. Teixeira, C. D. Huber, Proc. Natl. Acad. Sci. U.S.A. 118, 10 (2021)] that challenges some fundamental assumptions in conservation genetics, it is timely to summarize what the field has achieved, what robust patterns have emerged, and worthwhile future research directions. We consider theory and methodological breakthroughs that have helped management, and we outline some fundamental and applied challenges for conservation genetics.
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Affiliation(s)
- Yvonne Willi
- Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland
| | - Torsten N Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg 9220, Denmark
| | - Carla M Sgrò
- School of Biological Sciences, Monash University, Melbourne, VIC 3800, Australia
| | - Andrew R Weeks
- School of BioSciences, Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia
- Cesar Australia, Brunswick, VIC 3056, Australia
| | - Michael Ørsted
- Department of Chemistry and Bioscience, Aalborg University, Aalborg 9220, Denmark
- Department of Biology, Aarhus University, Aarhus 8000, Denmark
| | - Ary A Hoffmann
- School of BioSciences, Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia;
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Gauffre B, Boissinot A, Quiquempois V, Leblois R, Grillet P, Morin S, Picard D, Ribout C, Lourdais O. Agricultural intensification alters marbled newt genetic diversity and gene flow through density and dispersal reduction. Mol Ecol 2021; 31:119-133. [PMID: 34674328 DOI: 10.1111/mec.16236] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/08/2021] [Accepted: 10/18/2021] [Indexed: 11/30/2022]
Abstract
Recent agricultural intensification threatens global biodiversity with amphibians being one of the most impacted groups. Because of their biphasic life cycle, amphibians are particularly vulnerable to habitat loss and fragmentation that often result in small, isolated populations and loss of genetic diversity. Here, we studied how landscape heterogeneity affects genetic diversity, gene flow and demographic parameters in the marbled newt, Triturus marmoratus, over a hedgerow network landscape in Western France. While the northern part of the study area consists of preserved hedged farmland, the southern part was more profoundly converted for intensive arable crops production after WWII. Based on 67 sampled ponds and 10 microsatellite loci, we characterized regional population genetic structure and evaluated the correlation between landscape variables and (i) local genetic diversity using mixed models and (ii) genetic distance using multiple regression methods and commonality analysis. We identified a single genetic population characterized by a spatially heterogeneous isolation-by-distance pattern. Pond density in the surrounding landscape positively affected local genetic diversity while arable crop land cover negatively affected gene flow and connectivity. We used demographic inferences to quantitatively assess differences in effective population density and dispersal between the contrasted landscapes characterizing the northern and southern parts of the study area. Altogether, results suggest recent land conversion affected T. marmoratus through reduction in both effective population density and dispersal due to habitat loss and reduced connectivity.
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Affiliation(s)
- Bertrand Gauffre
- INRAE, UR 1115 PSH, Plantes et Systèmes de culture Horticoles, Avignon, France.,School of Biological Sciences, Monash University, Clayton, Vic., Australia
| | - Alexandre Boissinot
- CNRS, UMR 7372 CEBC - Université de La Rochelle, Villiers-en-Bois, France.,Réserve Naturelle Régionale du Bocage des Antonins - Deux-Sèvres Nature Environnement, Niort, France
| | | | - Raphael Leblois
- CBGP UMR 1062, INRAE, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier, Montpellier, France.,Institut de Biologie Computationnelle, Univ. Montpellier, Montpelier, France
| | - Pierre Grillet
- CNRS, UMR 7372 CEBC - Université de La Rochelle, Villiers-en-Bois, France
| | - Sophie Morin
- Office Français de la Biodiversité, Villiers-en-Bois, France
| | - Damien Picard
- Département de Biologie, UFR Sciences, Angers, France
| | - Cécile Ribout
- CNRS, UMR 7372 CEBC - Université de La Rochelle, Villiers-en-Bois, France
| | - Olivier Lourdais
- CNRS, UMR 7372 CEBC - Université de La Rochelle, Villiers-en-Bois, France.,School of Life Sciences, Arizona State University, Tempe, AZ, USA
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5
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Evolutionary history and genetic connectivity across highly fragmented populations of an endangered daisy. Heredity (Edinb) 2021; 126:846-858. [PMID: 33608651 PMCID: PMC8102499 DOI: 10.1038/s41437-021-00413-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 01/24/2021] [Accepted: 01/25/2021] [Indexed: 01/31/2023] Open
Abstract
Conservation management can be aided by knowledge of genetic diversity and evolutionary history, so that ecological and evolutionary processes can be preserved. The Button Wrinklewort daisy (Rutidosis leptorrhynchoides) was a common component of grassy ecosystems in south-eastern Australia. It is now endangered due to extensive habitat loss and the impacts of livestock grazing, and is currently restricted to a few small populations in two regions >500 km apart, one in Victoria, the other in the Australian Capital Territory and nearby New South Wales (ACT/NSW). Using a genome-wide SNP dataset, we assessed patterns of genetic structure and genetic differentiation of 12 natural diploid populations. We estimated intrapopulation genetic diversity to scope sources for genetic management. Bayesian clustering and principal coordinate analyses showed strong population genetic differentiation between the two regions, and substantial substructure within ACT/NSW. A coalescent tree-building approach implemented in SNAPP indicated evolutionary divergence between the two distant regions. Among the populations screened, the last two known remaining Victorian populations had the highest genetic diversity, despite having among the lowest recent census sizes. A maximum likelihood population tree method implemented in TreeMix suggested little or no recent gene flow except potentially between very close neighbours. Populations that were more genetically distinctive had lower genetic diversity, suggesting that drift in isolation is likely driving population differentiation though loss of diversity, hence re-establishing gene flow among them is desirable. These results provide background knowledge for evidence-based conservation and support genetic rescue within and between regions to elevate genetic diversity and alleviate inbreeding.
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6
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Use of genetic tools to assess predation on reintroduced howler monkeys (Alouatta caraya) in Northeastern Argentina. Primates 2021; 62:521-528. [PMID: 33609193 DOI: 10.1007/s10329-021-00896-9] [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: 07/07/2020] [Accepted: 02/04/2021] [Indexed: 10/22/2022]
Abstract
Despite strong support from the media, the reintroduction of animals into natural environments does not always achieve its goal. Alouatta caraya is the primate species facing the greatest hunting pressure due to the illegal pet trade in Argentina. Confiscations of this species are common, as is the voluntary surrender of animals by owners no longer able or willing to care for them. These animals ultimately arrive at rehabilitation centers and, in many cases, are released into natural environments that may differ from the original sites where they were captured. Until recently, the lack of genetic analysis of the individuals involved led to biased relocation decisions. We followed the reintroduction of 12 A. caraya individuals in a protected area (Isla Palacio, Misiones, Argentina). The presence of potential predators such as pumas (Puma concolor) and jaguars (Panthera onca) in this area was confirmed by camera traps, footprints and feces. After the disappearance of four A. caraya at the reintroduction site, we investigated the applicability of genetic assignment tests based on genotypic data to accurately identify predated individuals. Genetic analyses allowed us to determine the predator species (P. onca) and to identify the predated individuals as two of the reintroduced animals. This procedure is promising for identifying the remains of predated individuals, and can contribute to the design of reintroduction policies based on scientific evidence.
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7
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Do We Need to Identify Adaptive Genetic Variation When Prioritizing Populations for Conservation? CONSERV GENET 2021. [DOI: 10.1007/s10592-020-01327-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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8
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Brauer CJ, Beheregaray LB. Recent and rapid anthropogenic habitat fragmentation increases extinction risk for freshwater biodiversity. Evol Appl 2020; 13:2857-2869. [PMID: 33294027 PMCID: PMC7691462 DOI: 10.1111/eva.13128] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 12/16/2022] Open
Abstract
Anthropogenic habitat fragmentation is often implicated as driving the current global extinction crisis, particularly in freshwater ecosystems. The genetic signal of recent population isolation can be confounded by the complex spatial arrangement of dendritic river systems. Consequently, many populations may presently be managed separately based on an incorrect assumption that they have evolved in isolation. Integrating landscape genomics data with models of connectivity that account for landscape structure, we show that the cumulative effects of multiple in-stream barriers have contributed to the recent decline of a freshwater fish from the Murray-Darling Basin, Australia. In addition, individual-based eco-evolutionary simulations further demonstrate that contemporary inferences about population isolation are consistent with the 160-year time frame since construction of in-stream barriers began in the region. Our findings suggest that the impact of very recent fragmentation may be often underestimated for freshwater biodiversity. We argue that proactive conservation measures to reconnect many riverine populations are urgently needed.
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Affiliation(s)
- Chris J. Brauer
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityAdelaideSAAustralia
| | - Luciano B. Beheregaray
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityAdelaideSAAustralia
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9
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Taft HR, McCoskey DN, Miller JM, Pearson SK, Coleman MA, Fletcher NK, Mittan CS, Meek MH, Barbosa S. Research–management partnerships: An opportunity to integrate genetics in conservation actions. CONSERVATION SCIENCE AND PRACTICE 2020. [DOI: 10.1111/csp2.218] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
| | | | - Joshua M. Miller
- Department of Biological SciencesUniversity of Alberta Edmonton Alberta Canada
| | - Sarah K. Pearson
- College of Science and EngineeringFlinders University of South Australia Adelaide South Australia Australia
| | - Melinda A. Coleman
- Department of Primary Industries NSW FisheriesNational Marine Science Centre Coffs Harbour New South Wales Australia
- National Marine Science CentreSouthern Cross University Coffs Harbour New South Wales Australia
| | - Nicholas K. Fletcher
- Department of Ecology and Evolutionary BiologyCornell University, Corson Hall Ithaca New York USA
| | - Cinnamon S. Mittan
- Department of Ecology and Evolutionary BiologyCornell University, Corson Hall Ithaca New York USA
| | - Mariah H. Meek
- Department of Integrative BiologyMichigan State University East Lansing Michigan USA
| | - Soraia Barbosa
- Department of Fish and Wildlife SciencesUniversity of Idaho Moscow Idaho USA
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10
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Hardouin EA, Baltazar‐Soares M, Schilling A, Butler H, García‐Rodríguez O, Crowley E, Liang W, Meredith A, Lurz PWW, Forster J, Kenward RE, Hodder KH. Conservation of genetic uniqueness in remaining populations of red squirrels ( Sciurus vulgaris L.) in the South of England. Ecol Evol 2019; 9:6547-6558. [PMID: 31236243 PMCID: PMC6580283 DOI: 10.1002/ece3.5233] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 04/04/2019] [Accepted: 04/09/2019] [Indexed: 11/21/2022] Open
Abstract
The Eurasian red squirrel (Sciurus vulgaris) is an emblematic species for conservation, and its decline in the British Isles exemplifies the impact that alien introductions can have on native ecosystems. Indeed, red squirrels in this region have declined dramatically over the last 60 years due to the spread of squirrelpox virus following the introduction of the gray squirrel (Sciurus carolinensis). Currently, red squirrel populations in Britain are fragmented and need to be closely monitored in order to assess their viability and the effectiveness of conservation efforts. The situation is even more dramatic in the South of England, where S. vulgaris survives only on islands (Brownsea Island, Furzey Island, and the Isle of Wight). Using the D-loop, we investigated the genetic diversity and putative ancestry of the squirrels from Southern England and compared them to a European dataset composed of 1,016 samples from 54 populations. We found that our three populations were more closely related to other squirrels from the British Isles than squirrels from Europe, showed low genetic diversity, and also harbored several private haplotypes. Our study demonstrates how genetically unique the Southern English populations are in comparison with squirrels from the continental European range. We report the presence of four private haplotypes, suggesting that these populations may potentially harbor distinct genetic lineages. Our results emphasize the importance of preserving these isolated red squirrel populations for the conservation of the species.
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Affiliation(s)
- Emilie A. Hardouin
- Department of Life and Environmental Sciences, Faculty of Science and TechnologyBournemouth UniversityDorsetUK
| | - Miguel Baltazar‐Soares
- Department of Life and Environmental Sciences, Faculty of Science and TechnologyBournemouth UniversityDorsetUK
| | - Anna‐Katarina Schilling
- Royal (Dick) School of Veterinary Sciences, Easter Bush CampusUniversity of EdinburghMidlothianUK
- Moredun Research InstitutePentlands Science ParkPenicuikUK
| | | | - Oxala García‐Rodríguez
- Department of Life and Environmental Sciences, Faculty of Science and TechnologyBournemouth UniversityDorsetUK
| | - Eloise Crowley
- Department of Life and Environmental Sciences, Faculty of Science and TechnologyBournemouth UniversityDorsetUK
| | - Wei‐Jun Liang
- Department of Life and Environmental Sciences, Faculty of Science and TechnologyBournemouth UniversityDorsetUK
| | - Anna Meredith
- Royal (Dick) School of Veterinary Sciences, Easter Bush CampusUniversity of EdinburghMidlothianUK
- Faculty of Veterinary and Agricultural Sciences, Parkville CampusThe University of MelbourneMelbourneVictoriaAustralia
| | - Peter W. W. Lurz
- Royal (Dick) School of Veterinary Sciences, Easter Bush CampusUniversity of EdinburghMidlothianUK
| | - Jane Forster
- WISH Lab, Academic Unit of Cancer Sciences, Faculty of MedicineUniversity of SouthamptonSouthamptonUK
| | | | - Kathy H. Hodder
- Department of Life and Environmental Sciences, Faculty of Science and TechnologyBournemouth UniversityDorsetUK
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11
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Chan WY, Hoffmann AA, Oppen MJH. Hybridization as a conservation management tool. Conserv Lett 2019. [DOI: 10.1111/conl.12652] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Wing Yan Chan
- Australian Institute of Marine Science Townsville Queensland Australia
- School of BioSciencesUniversity of Melbourne Melbourne Victoria Australia
| | - Ary A. Hoffmann
- Bio21 InstituteUniversity of Melbourne Melbourne Victoria Australia
| | - Madeleine J. H. Oppen
- Australian Institute of Marine Science Townsville Queensland Australia
- School of BioSciencesUniversity of Melbourne Melbourne Victoria Australia
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12
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Artificial barriers prevent genetic recovery of small isolated populations of a low-mobility freshwater fish. Heredity (Edinb) 2018; 120:515-532. [PMID: 29326479 PMCID: PMC5943333 DOI: 10.1038/s41437-017-0008-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/05/2017] [Accepted: 09/08/2017] [Indexed: 11/08/2022] Open
Abstract
Habitat loss and fragmentation often result in small, isolated populations vulnerable to environmental disturbance and loss of genetic diversity. Low genetic diversity can increase extinction risk of small populations by elevating inbreeding and inbreeding depression, and reducing adaptive potential. Due to their linear nature and extensive use by humans, freshwater ecosystems are especially vulnerable to habitat loss and fragmentation. Although the effects of fragmentation on genetic structure have been extensively studied in migratory fishes, they are less understood in low-mobility species. We estimated impacts of instream barriers on genetic structure and diversity of the low-mobility river blackfish (Gadopsis marmoratus) within five streams separated by weirs or dams constructed 45-120 years ago. We found evidence of small-scale (<13 km) genetic structure within reaches unimpeded by barriers, as expected for a fish with low mobility. Genetic diversity was lower above barriers in small streams only, regardless of barrier age. In particular, one isolated population showed evidence of a recent bottleneck and inbreeding. Differentiation above and below the barrier (FST = 0.13) was greatest in this stream, but in other streams did not differ from background levels. Spatially explicit simulations suggest that short-term barrier effects would not be detected with our data set unless effective population sizes were very small (<100). Our study highlights that, in structured populations, the ability to detect short-term genetic effects from barriers is reduced and requires more genetic markers compared to panmictic populations. We also demonstrate the importance of accounting for natural population genetic structure in fragmentation studies.
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Wereszczuk A, Leblois R, Zalewski A. Genetic diversity and structure related to expansion history and habitat isolation: stone marten populating rural-urban habitats. BMC Ecol 2017; 17:46. [PMID: 29273026 PMCID: PMC5741947 DOI: 10.1186/s12898-017-0156-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 12/13/2017] [Indexed: 11/10/2022] Open
Abstract
Background Population genetic diversity and structure are determined by past and current evolutionary processes, among which spatially limited dispersal, genetic drift, and shifts in species distribution boundaries have major effects. In most wildlife species, environmental modifications by humans often lead to contraction of species’ ranges and/or limit their dispersal by acting as environmental barriers. However, in species well adapted to anthropogenic habitat or open landscapes, human induced environmental changes may facilitate dispersal and range expansions. In this study, we analysed whether isolation by distance and deforestation, among other environmental features, promotes or restricts dispersal and expansion in stone marten (Martes foina) populations. Results We genotyped 298 martens from eight sites at twenty-two microsatellite loci to characterize the genetic variability, population structure and demographic history of stone martens in Poland. At the landscape scale, limited genetic differentiation between sites in a mosaic of urban, rural and forest habitats was mostly influenced by isolation by distance. Statistical clustering and multivariate analyses showed weak genetic structuring with two to four clusters and a high rate of gene flow between them. Stronger genetic differentiation was detected for one stone marten population (NE1) located inside a large forest complex. Genetic differentiation between this site and all others was 20% higher than between other sites separated by similar distances. The genetic uniqueness index of NE1 was also twofold higher than in other sites. Past demographic history analyses showed recent expansion of this species in north-eastern Poland. A decrease in genetic diversity from south to north, and MIGRAINE analyses indicated the direction of expansion of stone marten. Conclusions Our results showed that two processes, changes in species distribution boundaries and limited dispersal associated with landscape barriers, affect genetic diversity and structure in stone marten. Analysis of local barriers that reduced dispersal and large scale analyses of genetic structure and demographic history highlight the importance of isolation by distance and forest cover for the past colonization of central Europe by stone marten. This confirmed the hypothesis that human-landscape changes (deforestation) accelerated stone marten expansion, to which climate warming probably has also been contributing over the last few decades. Electronic supplementary material The online version of this article (10.1186/s12898-017-0156-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anna Wereszczuk
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland.
| | - Raphaël Leblois
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, University Montpellier, Montpellier, France.,Institut de Biologie Computationnelle, University Montpellier, Montpellier, France
| | - Andrzej Zalewski
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland
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Ralls K, Ballou JD, Dudash MR, Eldridge MDB, Fenster CB, Lacy RC, Sunnucks P, Frankham R. Call for a Paradigm Shift in the Genetic Management of Fragmented Populations. Conserv Lett 2017. [DOI: 10.1111/conl.12412] [Citation(s) in RCA: 209] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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15
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Pavlova A, Beheregaray LB, Coleman R, Gilligan D, Harrisson KA, Ingram BA, Kearns J, Lamb AM, Lintermans M, Lyon J, Nguyen TTT, Sasaki M, Tonkin Z, Yen JDL, Sunnucks P. Severe consequences of habitat fragmentation on genetic diversity of an endangered Australian freshwater fish: A call for assisted gene flow. Evol Appl 2017; 10:531-550. [PMID: 28616062 PMCID: PMC5469170 DOI: 10.1111/eva.12484] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 03/29/2017] [Indexed: 12/15/2022] Open
Abstract
Genetic diversity underpins the ability of populations to persist and adapt to environmental changes. Substantial empirical data show that genetic diversity rapidly deteriorates in small and isolated populations due to genetic drift, leading to reduction in adaptive potential and fitness and increase in inbreeding. Assisted gene flow (e.g. via translocations) can reverse these trends, but lack of data on fitness loss and fear of impairing population "uniqueness" often prevents managers from acting. Here, we use population genetic and riverscape genetic analyses and simulations to explore the consequences of extensive habitat loss and fragmentation on population genetic diversity and future population trajectories of an endangered Australian freshwater fish, Macquarie perch Macquaria australasica. Using guidelines to assess the risk of outbreeding depression under admixture, we develop recommendations for population management, identify populations requiring genetic rescue and/or genetic restoration and potential donor sources. We found that most remaining populations of Macquarie perch have low genetic diversity, and effective population sizes below the threshold required to retain adaptive potential. Our simulations showed that under management inaction, smaller populations of Macquarie perch will face inbreeding depression within a few decades, but regular small-scale translocations will rapidly rescue populations from inbreeding depression and increase adaptive potential through genetic restoration. Despite the lack of data on fitness loss, based on our genetic data for Macquarie perch populations, simulations and empirical results from other systems, we recommend regular and frequent translocations among remnant populations within catchments. These translocations will emulate the effect of historical gene flow and improve population persistence through decrease in demographic and genetic stochasticity. Increasing population genetic connectivity within each catchment will help to maintain large effective population sizes and maximize species adaptive potential. The approach proposed here could be readily applicable to genetic management of other threatened species to improve their adaptive potential.
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Affiliation(s)
- Alexandra Pavlova
- School of Biological SciencesClayton Campus, Monash UniversityClaytonVICAustralia
| | | | - Rhys Coleman
- Applied ResearchMelbourne WaterDocklandsVICAustralia
| | - Dean Gilligan
- Freshwater Ecosystems ResearchNSW Department of Primary Industries – FisheriesBatemans BayNSWAustralia
| | - Katherine A. Harrisson
- School of Biological SciencesClayton Campus, Monash UniversityClaytonVICAustralia
- Department of Environment, Land Water and PlanningArthur Rylah Institute, Land, Fire and EnvironmentHeidelbergVICAustralia
- Department of Ecology Environment and EvolutionSchool of Life Sciences, La Trobe UniversityBundoora, Victoria3083Australia
| | - Brett A. Ingram
- Department of Economic DevelopmentJobs, Transport and ResourcesFisheries VictoriaAlexandraVICAustralia
| | - Joanne Kearns
- Department of Environment, Land Water and PlanningArthur Rylah Institute, Land, Fire and EnvironmentHeidelbergVICAustralia
| | - Annika M. Lamb
- School of Biological SciencesClayton Campus, Monash UniversityClaytonVICAustralia
| | - Mark Lintermans
- Institute for Applied EcologyUniversity of CanberraCanberraACTAustralia
| | - Jarod Lyon
- Department of Environment, Land Water and PlanningArthur Rylah Institute, Land, Fire and EnvironmentHeidelbergVICAustralia
| | - Thuy T. T. Nguyen
- Agriculture VictoriaAgriBio, Centre for AgriBioscienceBundooraVICAustralia
| | - Minami Sasaki
- School of Biological SciencesFlinders UniversityAdelaideSAAustralia
| | - Zeb Tonkin
- Department of Environment, Land Water and PlanningArthur Rylah Institute, Land, Fire and EnvironmentHeidelbergVICAustralia
| | - Jian D. L. Yen
- School of Physics and AstronomyClayton Campus, Monash UniversityClaytonVICAustralia
| | - Paul Sunnucks
- School of Biological SciencesClayton Campus, Monash UniversityClaytonVICAustralia
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16
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Lean J, Hammer MP, Unmack PJ, Adams M, Beheregaray LB. Landscape genetics informs mesohabitat preference and conservation priorities for a surrogate indicator species in a highly fragmented river system. Heredity (Edinb) 2017; 118:374-384. [PMID: 27876805 PMCID: PMC5345605 DOI: 10.1038/hdy.2016.111] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Revised: 09/27/2016] [Accepted: 09/27/2016] [Indexed: 11/09/2022] Open
Abstract
Poor dispersal species represent conservative benchmarks for biodiversity management because they provide insights into ecological processes influenced by habitat fragmentation that are less evident in more dispersive organisms. Here we used the poorly dispersive and threatened river blackfish (Gadopsis marmoratus) as a surrogate indicator system for assessing the effects of fragmentation in highly modified river basins and for prioritizing basin-wide management strategies. We combined individual, population and landscape-based approaches to analyze genetic variation in samples spanning the distribution of the species in Australia's Murray-Darling Basin, one of the world's most degraded freshwater systems. Our results indicate that G. marmoratus displays the hallmark of severe habitat fragmentation with notably scattered, small and demographically isolated populations with very low genetic diversity-a pattern found not only between regions and catchments but also between streams within catchments. By using hierarchically nested population sampling and assessing relationships between genetic uniqueness and genetic diversity across populations, we developed a spatial management framework that includes the selection of populations in need of genetic rescue. Landscape genetics provided an environmental criterion to identify associations between landscape features and ecological processes. Our results further our understanding of the impact that habitat quality and quantity has on habitat specialists with similarly low dispersal. They should also have practical applications for prioritizing both large- and small-scale conservation management actions for organisms inhabiting highly fragmented ecosystems.
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Affiliation(s)
- J Lean
- Molecular Ecology Laboratory, School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia
| | - M P Hammer
- Evolutionary Biology Unit, South Australian Museum, North Terrace, Adelaide, South Australia, Australia
- Curator of Fishes, Museum and Art Gallery of the Northern Territory, Darwin, Northern Territory, Australia
| | - P J Unmack
- Institute for Applied Ecology and Collaborative Research Network for Murray-Darling Basin Futures, University of Canberra, Canberra, Australian Capital Territory, Australia
| | - M Adams
- Evolutionary Biology Unit, South Australian Museum, North Terrace, Adelaide, South Australia, Australia
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - L B Beheregaray
- Molecular Ecology Laboratory, School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia
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17
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Vila M, Hermida M, Fernández C, Perea S, Doadrio I, Amaro R, San Miguel E. Phylogeography and Conservation Genetics of the Ibero-Balearic Three-Spined Stickleback (Gasterosteus aculeatus). PLoS One 2017; 12:e0170685. [PMID: 28118391 PMCID: PMC5261773 DOI: 10.1371/journal.pone.0170685] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 01/09/2017] [Indexed: 02/03/2023] Open
Abstract
Genetic isolation and drift may imperil peripheral populations of wide-ranging species more than central ones. Therefore, information about species genetic variability and population structure is invaluable for conservation managers. The Iberian populations of three-spined stickleback lie at the southwestern periphery of the European distribution of Gasterosteus aculeatus. This teleost is a protected species in Portugal and Spain and local extinctions have been reported in both countries during the last decades. Our objectives were (i) to determine whether the Iberian populations of G. aculeatus are unique or composed of any of the major evolutionary lineages previously identified and (ii) to assess the evolutionary potential of these peripheral populations. We genotyped 478 individuals from 17 sites at 10 polymorphic microsatellite loci to evaluate the genetic variability and differentiation of the Ibero-Balearic populations. We also sequenced 1,165 bp of the mitochondrial genome in 331 of those individuals in order to complement the estimates of genetic diversity in the Ibero-Balearic region. We predicted the evolutionary potential of the different sites analysed based on the contribution of each of them to total allelic/mitochondrial diversity. An intraspecific phylogeny at European level was reconstructed using our data from the mitochondrial cytochrome b gene (755 bp) and published sequences. The so-called Transatlantic, European and Mediterranean mitochondrial lineages were found to be present in the Ibero-Balearic region. Their phylogeography suggests a history of multiple colonisations. The nuclear results show, however, a strong correlation between population structure and drainage system. The following basins should be prioritised by conservation policies in order to preserve those populations with the highest evolutionary potential: the Portuguese Vouga and Tagus as well as the Spanish Majorca and Limia. Maintenance of their connectivity, control of exotic species and monitoring of habitat properties are strongly recommended in those areas. Genetic variation alone cannot, however, ensure the persistence of these peripheral southern populations of G. aculeatus. On the one hand, the analysis of a historical sample from Eastern Spain (Penyscola) revealed no genetic erosion, which suggests a fairly sudden extinction of that population. On the other hand, the reintroduction program implemented in the Valencian Community has mostly failed despite our finding of similar level of genetic diversity between the wild source and the captive-bred released individuals.
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Affiliation(s)
- Marta Vila
- Universidade da Coruña, Evolutionary Biology Group (GIBE), Facultade de Ciencias, Campus da Zapateira, A Coruña, Spain
- * E-mail:
| | - Miguel Hermida
- Universidade de Santiago de Compostela, Departamento de Xenética, Facultade de Veterinaria, Avenida Carballo Calero s/n, Lugo, Spain
| | - Carlos Fernández
- Universidade de Santiago de Compostela, Departamento de Xenética, Facultade de Veterinaria, Avenida Carballo Calero s/n, Lugo, Spain
| | - Silvia Perea
- Museo Nacional de Ciencias Naturales, Departamento de Biodiversidad y Biología Evolutiva, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
| | - Ignacio Doadrio
- Museo Nacional de Ciencias Naturales, Departamento de Biodiversidad y Biología Evolutiva, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
| | - Rafaela Amaro
- Universidade de Santiago de Compostela, Departamento de Xenética, Facultade de Veterinaria, Avenida Carballo Calero s/n, Lugo, Spain
| | - Eduardo San Miguel
- Universidade de Santiago de Compostela, Departamento de Xenética, Facultade de Veterinaria, Avenida Carballo Calero s/n, Lugo, Spain
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18
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Genetic diversity and divergence in the endangered Cape Verde warbler Acrocephalus brevipennis. CONSERV GENET 2016. [DOI: 10.1007/s10592-016-0909-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Brauer CJ, Hammer MP, Beheregaray LB. Riverscape genomics of a threatened fish across a hydroclimatically heterogeneous river basin. Mol Ecol 2016; 25:5093-5113. [DOI: 10.1111/mec.13830] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/15/2016] [Accepted: 08/23/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Chris J. Brauer
- Molecular Ecology Laboratory School of Biological Sciences Flinders University Adelaide SA 5042 Australia
| | - Michael P. Hammer
- Natural Sciences, Museum and Art Gallery of the Northern Territory Darwin NT 0801 Australia
| | - Luciano B. Beheregaray
- Molecular Ecology Laboratory School of Biological Sciences Flinders University Adelaide SA 5042 Australia
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20
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Richardson JL, Brady SP, Wang IJ, Spear SF. Navigating the pitfalls and promise of landscape genetics. Mol Ecol 2016; 25:849-63. [PMID: 26756865 DOI: 10.1111/mec.13527] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 12/12/2015] [Accepted: 01/07/2016] [Indexed: 12/17/2022]
Abstract
The field of landscape genetics has been evolving rapidly since its emergence in the early 2000s. New applications, techniques and criticisms of techniques appear like clockwork with each new journal issue. The developments are an encouraging, and at times bewildering, sign of progress in an exciting new field of study. However, we suggest that the rapid expansion of landscape genetics has belied important flaws in the development of the field, and we add an air of caution to this breakneck pace of expansion. Specifically, landscape genetic studies often lose sight of the fundamental principles and complex consequences of gene flow, instead favouring simplistic interpretations and broad inferences not necessarily warranted by the data. Here, we describe common pitfalls that characterize such studies, and provide practical guidance to improve landscape genetic investigation, with careful consideration of inferential limits, scale, replication, and the ecological and evolutionary context of spatial genetic patterns. Ultimately, the utility of landscape genetics will depend on translating the relationship between gene flow and landscape features into an understanding of long-term population outcomes. We hope the perspective presented here will steer landscape genetics down a more scientifically sound and productive path, garnering a field that is as informative in the future as it is popular now.
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Affiliation(s)
- Jonathan L Richardson
- Department of Biology, Providence College, 1 Cunningham Square, Providence, RI, 02918, USA
| | - Steven P Brady
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
| | - Ian J Wang
- Department of Environmental Science, Policy & Management, University of California, Berkeley, CA, 94720, USA
| | - Stephen F Spear
- The Orianne Society, 100 Phoenix Rd., Athens, GA, 30605, USA
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21
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Weeks AR, Stoklosa J, Hoffmann AA. Conservation of genetic uniqueness of populations may increase extinction likelihood of endangered species: the case of Australian mammals. Front Zool 2016; 13:31. [PMID: 27398088 PMCID: PMC4939060 DOI: 10.1186/s12983-016-0163-z] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/28/2016] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND As increasingly fragmented and isolated populations of threatened species become subjected to climate change, invasive species and other stressors, there is an urgent need to consider adaptive potential when making conservation decisions rather than focussing on past processes. In many cases, populations identified as unique and currently managed separately suffer increased risk of extinction through demographic and genetic processes. Other populations currently not at risk are likely to be on a trajectory where declines in population size and fitness soon appear inevitable. RESULTS Using datasets from natural Australian mammal populations, we show that drift processes are likely to be driving uniqueness in populations of many threatened species as a result of small population size and fragmentation. Conserving and managing such remnant populations separately will therefore often decrease their adaptive potential and increase species extinction risk. CONCLUSIONS These results highlight the need for a paradigm shift in conservation biology practise; strategies need to focus on the preservation of genetic diversity at the species level, rather than population, subspecies or evolutionary significant unit. The introduction of new genetic variants into populations through in situ translocation needs to be considered more broadly in conservation programs as a way of decreasing extinction risk by increasing neutral genetic diversity which may increase the adaptive potential of populations if adaptive variation is also increased.
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Affiliation(s)
- Andrew R. Weeks
- />School of BioSciences, Bio21 Institute, The University of Melbourne, Parkville, VIC 3010 Australia
| | - Jakub Stoklosa
- />School of Mathematics & Statistics and Evolution & Ecology Research Centre, The University of New South Wales, Kensington, NSW 2052 Australia
| | - Ary A. Hoffmann
- />School of BioSciences, Bio21 Institute, The University of Melbourne, Parkville, VIC 3010 Australia
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22
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Population genetics of a widely distributed small freshwater fish with varying conservation concerns: the southern purple-spotted gudgeon, Mogurnda adspersa. CONSERV GENET 2016. [DOI: 10.1007/s10592-016-0829-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Coleman RA, Hoffmann AA. Digenean trematode cysts within the heads of threatened Galaxiella species (Teleostei : Galaxiidae) from south-eastern Australia. AUST J ZOOL 2016. [DOI: 10.1071/zo16004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The dwarf galaxias (Galaxiella pusilla) and little galaxias (Galaxiella toourtkoourt) are both threatened freshwater fish from south-eastern Australia. Occasionally populations have been found with enlarged heads associated with the accumulation of ‘white balls’, but the cause of these deformities has not previously been investigated. In this study, histopathology and molecular techniques were employed to identify cysts extracted from the heads of Galaxiella species across six populations. Histopathology and DNA sequences from both mitochondrial (cytochrome c oxidase subunit I) and nuclear (ribosomal internal transcribed spacer 1) regions identified the cysts as metacercariae of Apatemon gracilis (Rudolphi, 1819), a cosmopolitan digenean trematode species. Heavy infestations of trematode metacercariae within Galaxiella populations are of concern due to the potential to cause increased mortality associated with altered behaviour of the fish host that increases the likelihood of predation. Direct mortality from infestations is also possible, but not quantified in this study.
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24
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Paz-Vinas I, Loot G, Stevens VM, Blanchet S. Evolutionary processes driving spatial patterns of intraspecific genetic diversity in river ecosystems. Mol Ecol 2015; 24:4586-604. [PMID: 26284462 DOI: 10.1111/mec.13345] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 07/30/2015] [Accepted: 08/13/2015] [Indexed: 01/17/2023]
Abstract
Describing, understanding and predicting the spatial distribution of genetic diversity is a central issue in biological sciences. In river landscapes, it is generally predicted that neutral genetic diversity should increase downstream, but there have been few attempts to test and validate this assumption across taxonomic groups. Moreover, it is still unclear what are the evolutionary processes that may generate this apparent spatial pattern of diversity. Here, we quantitatively synthesized published results from diverse taxa living in river ecosystems, and we performed a meta-analysis to show that a downstream increase in intraspecific genetic diversity (DIGD) actually constitutes a general spatial pattern of biodiversity that is repeatable across taxa. We further demonstrated that DIGD was stronger for strictly waterborne dispersing than for overland dispersing species. However, for a restricted data set focusing on fishes, there was no evidence that DIGD was related to particular species traits. We then searched for general processes underlying DIGD by simulating genetic data in dendritic-like river systems. Simulations revealed that the three processes we considered (downstream-biased dispersal, increase in habitat availability downstream and upstream-directed colonization) might generate DIGD. Using random forest models, we identified from simulations a set of highly informative summary statistics allowing discriminating among the processes causing DIGD. Finally, combining these discriminant statistics and approximate Bayesian computations on a set of twelve empirical case studies, we hypothesized that DIGD were most likely due to the interaction of two of these three processes and that contrary to expectation, they were not solely caused by downstream-biased dispersal.
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Affiliation(s)
- I Paz-Vinas
- Centre National de la Recherche Scientifique (CNRS), École Nationale de Formation Agronomique (ENFA), UMR 5174 EDB (Laboratoire Évolution & Diversité Biologique), Université Paul Sabatier, 118 route de Narbonne, 31062, Toulouse Cedex 4, France.,UPS, UMR 5174 (EDB), Université de Toulouse, 118 route de Narbonne, 31062, Toulouse Cedex 4, France.,UMR 7263 - IMBE, Équipe EGE, Centre Saint-Charles, Aix-Marseille Université, CNRS, IRD, Université d'Avignon et des Pays de Vaucluse, Case 36, 3 place Victor Hugo, 13331, Marseille Cedex 3, France
| | - G Loot
- UPS, UMR 5174 (EDB), Université de Toulouse, 118 route de Narbonne, 31062, Toulouse Cedex 4, France.,Station d'Écologie Expérimentale du CNRS à Moulis, USR 2936, Centre National de la Recherche Scientifique (CNRS), 2 route du CNRS, 09200, Moulis, France
| | - V M Stevens
- Station d'Écologie Expérimentale du CNRS à Moulis, USR 2936, Centre National de la Recherche Scientifique (CNRS), 2 route du CNRS, 09200, Moulis, France
| | - S Blanchet
- Centre National de la Recherche Scientifique (CNRS), École Nationale de Formation Agronomique (ENFA), UMR 5174 EDB (Laboratoire Évolution & Diversité Biologique), Université Paul Sabatier, 118 route de Narbonne, 31062, Toulouse Cedex 4, France.,Station d'Écologie Expérimentale du CNRS à Moulis, USR 2936, Centre National de la Recherche Scientifique (CNRS), 2 route du CNRS, 09200, Moulis, France
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25
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Kristensen TN, Hoffmann AA, Pertoldi C, Stronen AV. What can livestock breeders learn from conservation genetics and vice versa? Front Genet 2015; 6:38. [PMID: 25713584 PMCID: PMC4322732 DOI: 10.3389/fgene.2015.00038] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 01/26/2015] [Indexed: 11/17/2022] Open
Abstract
The management of livestock breeds and threatened natural population share common challenges, including small effective population sizes, high risk of inbreeding, and the potential benefits and costs associated with mixing disparate gene pools. Here, we consider what has been learnt about these issues, the ways in which the knowledge gained from one area might be applied to the other, and the potential of genomics to provide new insights. Although there are key differences stemming from the importance of artificial versus natural selection and the decreased level of environmental heterogeneity experienced by many livestock populations, we suspect that information from genetic rescue in natural populations could be usefully applied to livestock. This includes an increased emphasis on maintaining substantial population sizes at the expense of genetic uniqueness in ensuring future adaptability, and on emphasizing the way that environmental changes can influence the relative fitness of deleterious alleles and genotypes in small populations. We also suspect that information gained from cross-breeding and the maintenance of unique breeds will be increasingly important for the preservation of genetic variation in small natural populations. In particular, selected genes identified in domestic populations provide genetic markers for exploring adaptive evolution in threatened natural populations. Genomic technologies in the two disciplines will be important in the future in realizing genetic gains in livestock and maximizing adaptive capacity in wildlife, and particularly in understanding how parts of the genome may respond differently when exposed to population processes and selection.
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Affiliation(s)
- Torsten N. Kristensen
- Section of Biology and Environmental Science, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
| | - Ary A. Hoffmann
- Department of Zoology and Department of Genetics, Bio21 Institute, The University of MelbourneMelbourne, VIC, Australia
| | - Cino Pertoldi
- Section of Biology and Environmental Science, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
- Aalborg ZooAalborg, Denmark
| | - Astrid V. Stronen
- Section of Biology and Environmental Science, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
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26
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Shafer AB, Wolf JB, Alves PC, Bergström L, Bruford MW, Brännström I, Colling G, Dalén L, De Meester L, Ekblom R, Fawcett KD, Fior S, Hajibabaei M, Hill JA, Hoezel AR, Höglund J, Jensen EL, Krause J, Kristensen TN, Krützen M, McKay JK, Norman AJ, Ogden R, Österling EM, Ouborg NJ, Piccolo J, Popović D, Primmer CR, Reed FA, Roumet M, Salmona J, Schenekar T, Schwartz MK, Segelbacher G, Senn H, Thaulow J, Valtonen M, Veale A, Vergeer P, Vijay N, Vilà C, Weissensteiner M, Wennerström L, Wheat CW, Zieliński P. Genomics and the challenging translation into conservation practice. Trends Ecol Evol 2015; 30:78-87. [DOI: 10.1016/j.tree.2014.11.009] [Citation(s) in RCA: 278] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 11/20/2014] [Accepted: 11/21/2014] [Indexed: 10/24/2022]
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27
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Hoffmann A, Griffin P, Dillon S, Catullo R, Rane R, Byrne M, Jordan R, Oakeshott J, Weeks A, Joseph L, Lockhart P, Borevitz J, Sgrò C. A framework for incorporating evolutionary genomics into biodiversity conservation and management. ACTA ACUST UNITED AC 2015. [DOI: 10.1186/s40665-014-0009-x] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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28
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Miller AD, Sweeney OF, Whiterod NS, Van Rooyen AR, Hammer M, Weeks AR. Critically low levels of genetic diversity in fragmented populations of the endangered Glenelg spiny freshwater crayfish Euastacus bispinosus. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00609] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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