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Bertram A, Bell J, Brauer C, Fairclough D, Hamer P, Sandoval‐Castillo J, Wellenreuther M, Beheregaray LB. Estimation of effective number of breeders and effective population size in an abundant and heavily exploited marine teleost. Evol Appl 2024; 17:e13758. [PMID: 39040813 PMCID: PMC11261160 DOI: 10.1111/eva.13758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 05/16/2024] [Accepted: 07/03/2024] [Indexed: 07/24/2024] Open
Abstract
Obtaining reliable estimates of the effective number of breeders (N b) and generational effective population size (N e) for fishery-important species is challenging because they are often iteroparous and highly abundant, which can lead to bias and imprecision. However, recent advances in understanding of these parameters, as well as the development of bias correction methods, have improved the capacity to generate reliable estimates. We utilized samples of both single-cohort young of the year and mixed-age adults from two geographically and genetically isolated stocks of the Australasian snapper (Chrysophrys auratus) to investigate the feasibility of generating reliable N b and N e estimates for a fishery species. Snapper is an abundant, iteroparous broadcast spawning teleost that is heavily exploited by recreational and commercial fisheries. Employing neutral genome-wide SNPs and the linkage-disequilibrium method, we determined that the most reliable N b and N e estimates could be derived by genotyping at least 200 individuals from a single cohort. Although our estimates made from the mixed-age adult samples were generally lower and less precise than those based on a single cohort, they still proved useful for understanding relative differences in genetic effective size between stocks. The correction formulas applied to adjust for biases due to physical linkage of loci and age structure resulted in substantial upward modifications of our estimates, demonstrating the importance of applying these bias corrections. Our findings provide important guidelines for estimating N b and N e for iteroparous species with large populations. This work also highlights the utility of samples originally collected for stock structure and stock assessment work for investigating genetic effective size in fishery-important species.
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Affiliation(s)
- Andrea Bertram
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - Justin Bell
- Victorian Fisheries AuthorityQueenscliffVictoriaAustralia
| | - Chris Brauer
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - David Fairclough
- Department of Primary Industries and Regional DevelopmentAquatic Sciences and AssessmentHillarysWestern AustraliaAustralia
| | | | - Jonathan Sandoval‐Castillo
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - Maren Wellenreuther
- The New Zealand Institute for Plant and Food Research LimitedNelsonNew Zealand
- The School of Biological SciencesUniversity of AucklandAucklandNew Zealand
| | - Luciano B. Beheregaray
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
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2
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Vostry L, Vostra-Vydrova H, Moravcikova N, Kasarda R, Margetin M, Rychtarova J, Drzaic I, Shihabi M, Cubric-Curik V, Sölkner J, Curik I. Genomic analysis of conservation status, population structure and admixture in local Czech and Slovak dairy goat breeds. J Dairy Sci 2024:S0022-0302(24)00937-8. [PMID: 38908686 DOI: 10.3168/jds.2023-24607] [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: 12/23/2023] [Accepted: 05/30/2024] [Indexed: 06/24/2024]
Abstract
While dairy goat production, characterized by traditional production on small farms, is an important source of income in the Czech Republic and Slovakia, locally adapted breeds have not been fully consolidated over the last 100 years due to large fluctuations in population size and inconsistent breeding programs that allowed for different crossbreeding strategies. Our main objective in this study was therefore to assess the conservation status of 4 Czech (Alpine Goat, White Shorthair, Brown Shorthair and Czech Landrace) and one Slovak (Slovak White Shorthair) local goat breeds, to analyze their population structure and admixture, and to estimate their relatedness to several neighboring breeds. Our analyses included 142 goats belonging to 5 local breeds genotyped with the Illumina 50K BeadChip and 618 previously genotyped animals representing 15 goat breeds from Austria and Switzerland (all analyses based on 46,862 autosomal SNPs and 760 animals). In general, the conservation status of the Czech and Slovak local goat breeds was satisfactory, with the exception of the Brown Shorthair goat, as the analyzed parameters (heterozygosity, haplotype richness, ROH-based inbreeding and effective population size) were mostly above the median of 20 breeds. However, for all 5 Czech and Slovakian breeds, an examination of historical effective population size indicated a substantial decline about 8 to 22 generations ago. In addition, our study revealed that the Czech and Slovakian breeds are not fully consolidated; for instance, White Shorthair and Brown Shorthair were not clearly distinguishable. Considerable admixture, especially in Czech Landrace (effective number of parental clusters equal to 4.2), and low but numerous migration rates from other Austrian and Swiss breeds were found. These results provide valuable insights for future breeding programs and genetic diversity management of local Czech and Slovak goat breeds.
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Affiliation(s)
- Lubos Vostry
- Czech University of Life Science Prague, Kamycka 129, 16500 Prague, Czech Republic.
| | - Hana Vostra-Vydrova
- Czech University of Life Science Prague, Kamycka 129, 16500 Prague, Czech Republic
| | - Nina Moravcikova
- Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic
| | - Radovan Kasarda
- Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic
| | - Milan Margetin
- Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic
| | - Jana Rychtarova
- Institute of Animal Science, Přátelství 815, 104 00 Prague, Czech Republic
| | - Ivana Drzaic
- University of Zagreb, Faculty of Agriculture, Svetošimunska cesta 25, 10000 Zagreb, Croatia
| | - Mario Shihabi
- University of Zagreb, Faculty of Agriculture, Svetošimunska cesta 25, 10000 Zagreb, Croatia
| | - Vlatka Cubric-Curik
- University of Zagreb, Faculty of Agriculture, Svetošimunska cesta 25, 10000 Zagreb, Croatia
| | - Johan Sölkner
- University of Natural Resources & Life Sciences Vienna, Gregor-Mendel-Strasse 33, 1180 Vienna, Austria
| | - Ino Curik
- University of Zagreb, Faculty of Agriculture, Svetošimunska cesta 25, 10000 Zagreb, Croatia; Institute of Animal Sciences, Hungarian University of Agriculture and Life Sciences (MATE), Guba Sándor u. 40, 7400 Kaposvár, Hungary.
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3
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Kardos M, Waples RS. Low-coverage sequencing and Wahlund effect severely bias estimates of inbreeding, heterozygosity and effective population size in North American wolves. Mol Ecol 2024:e17415. [PMID: 38785346 DOI: 10.1111/mec.17415] [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: 02/16/2024] [Revised: 05/03/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024]
Abstract
vonHoldt et al. ((2024), Molecular Ecology, 33, e17231) (vH24) used low-coverage (average ~ 7X read depth) restriction site-associated DNA sequence data to estimate individual inbreeding and heterozygosity, and recent effective population size (Ne), in Great Lakes (GL) and Northern Rocky Mountain (RM) wolves. They concluded that RM heterozygosity rapidly declined between 1991 and 2020, and that Ne declined substantially in GL and RM over the last 50 generations. Here, we evaluate the effects of low sequence coverage and sampling strategy on vH24's findings and provide general recommendations for using sequence data to evaluate inbreeding, heterozygosity and Ne. Low-coverage sequencing resulted in downwardly biased estimates of individual inbreeding and heterozygosity, and an erroneous large temporal decline in RM heterozygosity due to declining read depth through time. Additionally, vH24's sampling strategy-which combined individuals from several genetically differentiated populations and across at least eight wolf generations-is expected to have resulted in severe downward bias in estimates of recent Ne for RM. We recommend using high-coverage sequence data (≥ $$ \ge $$ 15-20X) to estimate inbreeding and heterozygosity. Carefully filtering individuals, loci and genotypes, and using genotype imputation or likelihoods can help to minimise bias when low-coverage sequence data must be used. For estimation of contemporary Ne, the marginal benefits of using more than 103-104 loci are small, so aggressive filtering of loci with low average read depth potentially can retain most individuals without sacrificing much precision. Individuals are relatively more valuable than loci because analyses of contemporary Ne should focus on roughly single-generation samples from local breeding populations.
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Affiliation(s)
- Marty Kardos
- Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, Washington, USA
| | - Robin S Waples
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, USA
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4
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Gargiulo R, Decroocq V, González‐Martínez SC, Paz‐Vinas I, Aury J, Lesur Kupin I, Plomion C, Schmitt S, Scotti I, Heuertz M. Estimation of contemporary effective population size in plant populations: Limitations of genomic datasets. Evol Appl 2024; 17:e13691. [PMID: 38707994 PMCID: PMC11069024 DOI: 10.1111/eva.13691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 03/22/2024] [Accepted: 04/03/2024] [Indexed: 05/07/2024] Open
Abstract
Effective population size (N e) is a pivotal evolutionary parameter with crucial implications in conservation practice and policy. Genetic methods to estimate N e have been preferred over demographic methods because they rely on genetic data rather than time-consuming ecological monitoring. Methods based on linkage disequilibrium (LD), in particular, have become popular in conservation as they require a single sampling and provide estimates that refer to recent generations. A software program based on the LD method, GONE, looks particularly promising to estimate contemporary and recent-historical N e (up to 200 generations in the past). Genomic datasets from non-model species, especially plants, may present some constraints to the use of GONE, as linkage maps and reference genomes are seldom available, and SNP genotyping is usually based on reduced-representation methods. In this study, we use empirical datasets from four plant species to explore the limitations of plant genomic datasets when estimating N e using the algorithm implemented in GONE, in addition to exploring some typical biological limitations that may affect N e estimation using the LD method, such as the occurrence of population structure. We show how accuracy and precision of N e estimates potentially change with the following factors: occurrence of missing data, limited number of SNPs/individuals sampled, and lack of information about the location of SNPs on chromosomes, with the latter producing a significant bias, previously unexplored with empirical data. We finally compare the N e estimates obtained with GONE for the last generations with the contemporary N e estimates obtained with the programs currentNe and NeEstimator.
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Affiliation(s)
| | | | | | - Ivan Paz‐Vinas
- Department of BiologyColorado State UniversityFort CollinsColoradoUSA
- CNRS, ENTPE, UMR5023 LEHNAUniversité Claude Bernard Lyon 1VilleurbanneFrance
| | - Jean‐Marc Aury
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ EvryUniversité Paris‐SaclayEvryFrance
| | | | | | - Sylvain Schmitt
- AMAPUniv. Montpellier, CIRAD, CNRS, INRAE, IRDMontpellierFrance
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García-Castro KL, Márquez EJ. Temporal analysis of genetic diversity and gene flow in the threatened catfish Pseudoplatystoma magdaleniatum from a dammed neotropical river. PLoS One 2024; 19:e0301577. [PMID: 38635781 PMCID: PMC11025948 DOI: 10.1371/journal.pone.0301577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 03/19/2024] [Indexed: 04/20/2024] Open
Abstract
The striped catfish Pseudoplatystoma magdaleniatum is a large-sized migratory species from the north Andes region, endemic to Magdalena basin and one of the major fishery resources. Despite the estimated reduction of over 80% of the fisheries production of this species throughout the basin in recent decades, its population in the lower Magdalena-Cauca basin showed healthy genetics after molecular analyses. However, the current conservation status of this species and several habitat disturbances demand the re-evaluation of its population genetics to infer evolutionary risks and assess potential changes. This work analyzed a total of 164 samples from the Cauca River collected downstream the Ituango Dam between 2019-2021 using species-specific microsatellite markers to compare the genetic diversity and structure in samples collected between 2010-2014 from the lower Magdalena-Cauca basin, previously analyzed. Our results showed a relatively stable panmictic population over time (4 to 10 years), with high genetic diversity and evidence of recent bottleneck. Promoting habitat connectivity to conserve gene flow, characterizing diversity and genetic structure over the entire basin, and integrating the results with future monitoring are important aspects for the management planning for P. magdaleniatum in the Magdalena-Cauca basin.
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Affiliation(s)
- Kevin León García-Castro
- Facultad de Ciencias Universidad Nacional de Colombia–Sede Medellín, Laboratorio de Biología Molecular y Celular, Escuela de Biociencias, Medellín, Antioquia, Colombia
| | - Edna Judith Márquez
- Facultad de Ciencias Universidad Nacional de Colombia–Sede Medellín, Laboratorio de Biología Molecular y Celular, Escuela de Biociencias, Medellín, Antioquia, Colombia
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Furlan EM, Baumgartner LJ, Duncan M, Ellis I, Gruber B, Harrisson K, Michie L, Thiem JD, Stuart I. Swinging back from the brink? Polygamous mating strategies revealed for an iconic threatened freshwater fish. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 919:170808. [PMID: 38336046 DOI: 10.1016/j.scitotenv.2024.170808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Catastrophic fish death events are increasing in frequency and severity globally. A series of major recent fish deaths in the semi-arid lower Darling-Baaka river system (LDBR) of Australia are emblematic of these issues with tens of millions of native fish perishing. In 2018-2019 there was a major death event for Australia's largest freshwater fish, Murray cod (Maccullochella peelii). To aid the recovery and guide restoration activities of local Murray cod populations, it is essential to gather information on the mating strategies and effective population size following the fish death event. After the fish deaths, we collected larvae during the 2020 and 2021 breeding seasons and used single nucleotide polymorphisms (SNPs) to provide insight mating strategies and to estimate effective population size. Larvae were detected in both years along the entire length of the LDBR. Sixteen percent of the inferred breeding individuals were found to contribute to multiple pairings, confirming a complex and polygamous mating system. A high frequency of polygamy was evident both within and between years with 100 % polygamy identified among parents that produced offspring in both 2020 and 2021 and 95 % polygamy identified among parents involved in multiple spawning events within years. Post-larval Murray cod samples collected between 2016 and 2021 were co-analysed to further inform kinship patterns. Again, monogamy was rare with no confirmed cases of the same male-female pair contributing to multiple breeding events within or between seasons. Effective population size based on Murray cod collected after the fish death event was estimated at 721.6 (CI 471-1486), though this has likely declined following a subsequent catastrophic fish death event in the LDBR in March 2023. Our data provide insight into the variability of Murray cod mating strategies, and we anticipate that this knowledge will assist in planning conservation actions to ultimately help recover a species in crisis.
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Affiliation(s)
- Elise M Furlan
- Centre for Conservation Ecology and Genomics, Institute for Applied Ecology, University of Canberra, University Drive, Bruce, ACT 2617, Australia; Gulbali Institute for Agriculture, Water and Environment, Charles Sturt University, P.O. Box 789, Albury, NSW 2640, Australia.
| | - Lee J Baumgartner
- Gulbali Institute for Agriculture, Water and Environment, Charles Sturt University, P.O. Box 789, Albury, NSW 2640, Australia
| | - Meaghan Duncan
- Department of Primary Industries, Narrandera Fisheries Centre, Narrandera, New South Wales, Australia
| | - Iain Ellis
- Department of Primary Industries, Buronga, New South Wales, Australia
| | - Bernd Gruber
- Centre for Conservation Ecology and Genomics, Institute for Applied Ecology, University of Canberra, University Drive, Bruce, ACT 2617, Australia
| | - Katherine Harrisson
- Department of Environment and Genetics, La Trobe University, Melbourne, Australia; Research Centre for Future Landscapes, La Trobe University, Melbourne, Australia; Arthur Rylah Institute for Environmental Research, Department of Energy, Environment and Climate Action, Victoria, Australia
| | - Laura Michie
- Department of Primary Industries, Narrandera Fisheries Centre, Narrandera, New South Wales, Australia
| | - Jason D Thiem
- Department of Primary Industries, Narrandera Fisheries Centre, Narrandera, New South Wales, Australia
| | - Ivor Stuart
- Gulbali Institute for Agriculture, Water and Environment, Charles Sturt University, P.O. Box 789, Albury, NSW 2640, Australia
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7
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Pavlova A, Schneller NM, Lintermans M, Beitzel M, Robledo‐Ruiz DA, Sunnucks P. Planning and implementing genetic rescue of an endangered freshwater fish population in a regulated river, where low flow reduces breeding opportunities and may trigger inbreeding depression. Evol Appl 2024; 17:e13679. [PMID: 38617824 PMCID: PMC11009430 DOI: 10.1111/eva.13679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 02/11/2024] [Accepted: 02/26/2024] [Indexed: 04/16/2024] Open
Abstract
Augmenting depleted genetic diversity can improve the fitness and evolutionary potential of wildlife populations, but developing effective management approaches requires genetically monitored test cases. One such case is the small, isolated and inbred Cotter River population of an endangered Australian freshwater fish, the Macquarie perch Macquaria australasica, which over 3 years (2017-2019) received 71 translocated migrants from a closely related, genetically more diverse population. We used genetic monitoring to test whether immigrants bred, interbred with local fish and augmented population genetic diversity. We also investigated whether levels of river flow affected recruitment, inbreeding depression and juvenile dispersal. Fish length was used to estimate the age, birth year cohort and growth of 524 individuals born between 2016 and 2020 under variable flow conditions. DArT genome-wide genotypes were used to assess individual ancestry, heterozygosity, short-term effective population size and identify parent-offspring and full-sibling families. Of 442 individuals born after translocations commenced, only two (0.45%) were of mixed ancestry; these were half-sibs with one translocated parent in common. Numbers of breeders and genetic diversity for five birth year cohorts of the Cotter River fish were low, especially in low-flow years. Additionally, individuals born in the year of lowest flow evidently suffered from inbreeding depression for juvenile growth. The year of highest flow was associated with the largest number of breeders, lowest inbreeding in the offspring and greatest juvenile dispersal distances. Genetic diversity decreased in the upstream direction, flagging restricted access of breeders to the most upstream breeding sites, exacerbated by low river flow. Our results suggest that the effectiveness of translocations could be increased by focussing on upstream sites and moving more individuals per year; using riverine sources should be considered. Our results indicate that river flow sufficient to facilitate fish movement through the system would increase the number of breeders, promote individuals' growth, reduce inbreeding depression and promote genetic rescue.
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Affiliation(s)
- Alexandra Pavlova
- School of Biological SciencesMonash UniversityMelbourneVictoriaAustralia
| | - Nadja M. Schneller
- School of Biological SciencesMonash UniversityMelbourneVictoriaAustralia
| | - Mark Lintermans
- Centre for Applied Water ScienceInstitute for Applied Ecology, University of CanberraCanberraAustralian Capital TerritoryAustralia
| | - Matt Beitzel
- Environment, Planning & Sustainable Development Directorate (ACT Government)CanberraAustralian Capital TerritoryAustralia
| | | | - Paul Sunnucks
- School of Biological SciencesMonash UniversityMelbourneVictoriaAustralia
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Olah G, Waples RS, Stojanovic D. Influence of molecular marker type on estimating effective population size and other genetic parameters in a critically endangered parrot. Ecol Evol 2024; 14:e11102. [PMID: 38524913 PMCID: PMC10961163 DOI: 10.1002/ece3.11102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 02/15/2024] [Accepted: 02/20/2024] [Indexed: 03/26/2024] Open
Abstract
Genetics is a fast-moving field, and for conservation practitioners or ecologists, it can be bewildering. The choice of marker used in studies is fundamental; in the literature, preference has recently shifted from microsatellites to single nucleotide polymorphism (SNP) loci. Understanding how marker type affects estimates of population genetic parameters is important in the context of conservation, especially because the accuracy of estimates has a bearing on the actions taken to protect threatened species. We compare parameter estimates between seven microsatellites, 3761 SNP loci, and a random subset of 100 SNPs for the exact same 324 individual swift parrots, Lathamus discolor, and also use 457 additional samples from subsequent years to compare SNP estimates. Both marker types estimated a lower H O than H E. We show that microsatellites and SNPs mainly indicate a lack of spatial genetic structure, except when a priori collection locations were used on the SNP data in a discriminant analysis of principal components (DAPC). The 100-SNP subset gave comparable results to when the full dataset was used. Estimates of effective population size (N e) were comparable between markers when the same individuals were considered, but SNPs had narrower confidence intervals. This is reassuring because conservation assessments that rely on population genetic estimates based on a few microsatellites are unlikely to be nullified by the general shift toward SNPs in the literature. However, estimates between markers and datasets varied considerably when only adult samples were considered; hence, including samples of all age groups is recommended to be used when available. The estimated N e was higher for the full SNP dataset (2010-2019) than the smaller comparison data (2010-2015), which might be a better reflection of the species status. The lower precision of microsatellites may not necessarily be a barrier for most conservation applications; however, SNPs will improve confidence limits, which may be useful for practitioners.
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Affiliation(s)
- George Olah
- Fenner School of Environment and SocietyAustralian National UniversityCanberraAustralian Capital TerritoryAustralia
- King's Forensics, Department of Analytical, Environmental and Forensic Sciences, Faculty of Life Sciences and MedicineKing's College LondonLondonUK
| | - Robin S. Waples
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Dejan Stojanovic
- Fenner School of Environment and SocietyAustralian National UniversityCanberraAustralian Capital TerritoryAustralia
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Waples RS. Practical application of the linkage disequilibrium method for estimating contemporary effective population size: A review. Mol Ecol Resour 2024; 24:e13879. [PMID: 37873672 DOI: 10.1111/1755-0998.13879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 09/26/2023] [Accepted: 09/29/2023] [Indexed: 10/25/2023]
Abstract
The method to estimate contemporary effective population size (Ne ) based on patterns of linkage disequilibrium (LD) at unlinked loci has been widely applied to natural and managed populations. The underlying model makes many simplifying assumptions, most of which have been evaluated in numerous studies published over the last two decades. Here, these performance evaluations are reviewed and summarized, with a focus on information that facilitates practical application to real populations in nature. Potential sources of bias that are discussed include calculation of r2 (a measure of LD), adjustments for sampling error, physical linkage, age structure, migration and spatial structure, mutation and selection, mating systems, changes in abundance, rare alleles, missing data, genotyping errors, data filtering choices and methods for combining multiple Ne estimates. Factors that affect precision are reviewed, including pseudoreplication that limits the information gained from large genomics datasets, constraints imposed by small samples of individuals, and the challenges in obtaining robust estimates for large populations. Topics that merit further research include the potential to weight r2 values by allele frequency, lump samples of individuals, use genotypic likelihoods rather than called genotypes, prune large LD values and apply the method to species practising partial monogamy.
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Affiliation(s)
- Robin S Waples
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, USA
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10
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Santiago E, Caballero A, Köpke C, Novo I. Estimation of the contemporary effective population size from SNP data while accounting for mating structure. Mol Ecol Resour 2024; 24:e13890. [PMID: 37937674 DOI: 10.1111/1755-0998.13890] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 10/23/2023] [Accepted: 10/26/2023] [Indexed: 11/09/2023]
Abstract
A new method is developed to estimate the contemporary effective population size (Ne ) from linkage disequilibrium (LD) between SNPs without information on their location, which is the usual scenario in non-model species. The general theory of linkage disequilibrium is extended to include the contribution of full-sibs to the measure of LD, leading naturally to the estimation of Ne in monogamous and polygamous mating systems, as well as in multiparous species, and with non-random distributions of full-sib family size due to selection or other causes. Prediction of confidence intervals for Ne estimates was solved using a small artificial neural network trained on a dataset of over 105 simulation results. The method, implemented in a user-friendly and fast software (currentNe), is able to estimate Ne even in problematic scenarios with large population sizes or small sample sizes and provides confidence intervals that are more consistent than resampling methods.
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Affiliation(s)
- Enrique Santiago
- Departamento de Biología Funcional, Facultad de Biología, Universidad de Oviedo, Oviedo, Spain
| | - Armando Caballero
- Centro de Investigación Mariña, Universidade de Vigo, Facultade de Bioloxía, Vigo, Spain
| | | | - Irene Novo
- Centro de Investigación Mariña, Universidade de Vigo, Facultade de Bioloxía, Vigo, Spain
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Mathur S, Mason AJ, Bradburd GS, Gibbs HL. Functional genomic diversity is correlated with neutral genomic diversity in populations of an endangered rattlesnake. Proc Natl Acad Sci U S A 2023; 120:e2303043120. [PMID: 37844221 PMCID: PMC10614936 DOI: 10.1073/pnas.2303043120] [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: 02/22/2023] [Accepted: 09/19/2023] [Indexed: 10/18/2023] Open
Abstract
Theory predicts that genetic erosion in small, isolated populations of endangered species can be assessed using estimates of neutral genetic variation, yet this widely used approach has recently been questioned in the genomics era. Here, we leverage a chromosome-level genome assembly of an endangered rattlesnake (Sistrurus catenatus) combined with whole genome resequencing data (N = 110 individuals) to evaluate the relationship between levels of genome-wide neutral and functional diversity over historical and future timescales. As predicted, we found positive correlations between genome-wide estimates of neutral genetic diversity (π) and inferred levels of adaptive variation and an estimate of inbreeding mutation load, and a negative relationship between neutral diversity and an estimate of drift mutation load. However, these correlations were half as strong for projected future levels of neutral diversity based on contemporary effective population sizes. Broadly, our results confirm that estimates of neutral genetic diversity provide an accurate measure of genetic erosion in populations of a threatened vertebrate. They also provide nuance to the neutral-functional diversity controversy by suggesting that while these correlations exist, anthropogenetic impacts may have weakened these associations in the recent past and into the future.
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Affiliation(s)
- Samarth Mathur
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH48824
- Ohio Biodiversity Conservation Partnership, The Ohio State University, Columbus, OH43210
| | - Andrew J. Mason
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH48824
- Ohio Biodiversity Conservation Partnership, The Ohio State University, Columbus, OH43210
| | - Gideon S. Bradburd
- Evolution and Behavior Program, Department of Integrative Biology, Ecology, Michigan State University, East Lansing, MI48824
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI48109
| | - H. Lisle Gibbs
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH48824
- Ohio Biodiversity Conservation Partnership, The Ohio State University, Columbus, OH43210
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12
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Hirschfeld M, Barnett A, Sheaves M, Dudgeon C. What Darwin could not see: island formation and historical sea levels shape genetic divergence and island biogeography in a coastal marine species. Heredity (Edinb) 2023; 131:189-200. [PMID: 37400518 PMCID: PMC10462691 DOI: 10.1038/s41437-023-00635-4] [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: 08/28/2022] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 07/05/2023] Open
Abstract
Oceanic islands play a central role in the study of evolution and island biogeography. The Galapagos Islands are one of the most studied oceanic archipelagos but research has almost exclusively focused on terrestrial organisms compared to marine species. Here we used the Galapagos bullhead shark (Heterodontus quoyi) and single nucleotide polymorphisms (SNPs) to examine evolutionary processes and their consequences for genetic divergence and island biogeography in a shallow-water marine species without larval dispersal. The sequential separation of individual islands from a central island cluster gradually established different ocean depths between islands that pose barriers to dispersal in H. quoyi. Isolation by resistance analysis suggested that ocean bathymetry and historical sea level fluctuations modified genetic connectivity. These processes resulted in at least three genetic clusters that exhibit low genetic diversity and effective population sizes that scale with island size and the level of geographic isolation. Our results exemplify that island formation and climatic cycles shape genetic divergence and biogeography of coastal marine organisms with limited dispersal comparable to terrestrial taxa. Because similar scenarios exist in oceanic islands around the globe our research provides a new perspective on marine evolution and biogeography with implications for the conservation of island biodiversity.
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Affiliation(s)
- Maximilian Hirschfeld
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia.
- Galápagos Science Center, Universidad San Francisco de Quito, Isla San Cristóbal, Galápagos, Ecuador.
| | - Adam Barnett
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
- Marine Data Technology Hub, James Cook University, Townsville, Queensland, Australia
- Biopixel Oceans Foundation, Cairns, Queensland, Australia
| | - Marcus Sheaves
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
- Marine Data Technology Hub, James Cook University, Townsville, Queensland, Australia
| | - Christine Dudgeon
- Biopixel Oceans Foundation, Cairns, Queensland, Australia
- School of Biomedical Sciences, The University of Queensland, Saint Lucia, Queensland, Australia
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13
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Weise EM, Scribner KT, Boeberitz O, Bravener G, Johnson NS, Robinson JD. Evaluating the utility of effective breeding size estimates for monitoring sea lamprey spawning abundance. Ecol Evol 2023; 13:e10519. [PMID: 37745785 PMCID: PMC10511834 DOI: 10.1002/ece3.10519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/25/2023] [Accepted: 08/29/2023] [Indexed: 09/26/2023] Open
Abstract
Sea lamprey (Petromyzon marinus) is an invasive species that is a significant source of mortality for populations of valued fish species across the North American Great Lakes. Large annual control programs are needed to reduce the species' impacts; however, the number of successfully spawning adults cannot currently be accurately assessed. In this study, effective breeding size (N b) and the minimum number of spawning adults (N s) were estimated for larval cohorts from 17 tributaries across all five Great Lakes using single nucleotide polymorphisms (SNP) genotyped via RAD-capture sequencing. Reconstructed larval pedigrees showed substantial variability in the size and number of full- and half-sibling groups, N b (<1-367), and N s (5-545) among streams. Generalized linear models examining the effects of stream environmental characteristics and aspects of sampling regimes on N b and N s estimates identified sample size, the number of sampling sites, and drainage area as important factors predicting N b and N s. Correlations between N b, N s, and capture-mark-recapture estimates of adult census size (N c) increased when streams with small sample sizes (n < 50) were removed. Results collectively indicate that parameters estimated from genetic data can provide valuable information on spawning adults in a river system, especially if sampling regimes are standardized and physical stream covariates are included.
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Affiliation(s)
- Ellen M. Weise
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
- Present address:
Department of BiologyDalhousie UniversityHalifaxNova ScotiaCanada
| | - Kim T. Scribner
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
- Department of Integrative BiologyMichigan State UniversityEast LansingMichiganUSA
| | - Olivia Boeberitz
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
- Present address:
Pacific States Marine Fisheries CommissionPortlandOregonUSA
| | - Gale Bravener
- Fisheries and Oceans CanadaSea Lamprey Control CentreSault Ste. MarieOntarioCanada
| | - Nicholas S. Johnson
- U.S. Geological SurveyGreat Lakes Science Center, Hammond Bay Biological StationMillersburgMichiganUSA
| | - John D. Robinson
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
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14
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Crossman CA, Fontaine MC, Frasier TR. A comparison of genomic diversity and demographic history of the North Atlantic and Southwest Atlantic southern right whales. Mol Ecol 2023. [PMID: 37577945 DOI: 10.1111/mec.17099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 07/25/2023] [Accepted: 07/31/2023] [Indexed: 08/15/2023]
Abstract
Right whales (genus Eubalaena) were among the first, and most extensively pursued, targets of commercial whaling. However, understanding the impacts of this persecution requires knowledge of the demographic histories of these species prior to exploitation. We used deep whole genome sequencing (~40×) of 12 North Atlantic (E. glacialis) and 10 Southwest Atlantic southern (E. australis) right whales to quantify contemporary levels of genetic diversity and infer their demographic histories over time. Using coalescent- and identity-by-descent-based modelling to estimate ancestral effective population sizes from genomic data, we demonstrate that North Atlantic right whales have lived with smaller effective population sizes (Ne ) than southern right whales in the Southwest Atlantic since their divergence and describe the decline in both populations around the time of whaling. North Atlantic right whales exhibit reduced genetic diversity and longer runs of homozygosity leading to higher inbreeding coefficients compared to the sampled population of southern right whales. This study represents the first comprehensive assessment of genome-wide diversity of right whales in the western Atlantic and underscores the benefits of high coverage, genome-wide datasets to help resolve long-standing questions about how historical changes in effective population size over different time scales shape contemporary diversity estimates. This knowledge is crucial to improve our understanding of the right whales' history and inform our approaches to address contemporary conservation issues. Understanding and quantifying the cumulative impact of long-term small Ne , low levels of diversity and recent inbreeding on North Atlantic right whale recovery will be important next steps.
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Affiliation(s)
- Carla A Crossman
- Biology Department, Saint Mary's University, Halifax, Nova Scotia, Canada
| | - Michael C Fontaine
- Laboratoire MIVEGEC (Université de Montpellier, CNRS 5290, IRD 224), Montpellier, France
- Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, Groningen, The Netherlands
| | - Timothy R Frasier
- Biology Department, Saint Mary's University, Halifax, Nova Scotia, Canada
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15
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Waples RS. Robustness of Hill's overlapping-generation method for calculating N e to extreme patterns of reproductive success. Heredity (Edinb) 2023; 131:170-177. [PMID: 37337021 PMCID: PMC10382553 DOI: 10.1038/s41437-023-00633-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 06/09/2023] [Accepted: 06/09/2023] [Indexed: 06/21/2023] Open
Abstract
For species with overlapping generations, the most widely used method to calculate effective population size (Ne) is Hill's, the key parameter for which is lifetime variance in offspring number ([Formula: see text]). Hill's model assumes a stable age structure and constant abundance, and sensitivity to those assumptions has been evaluated previously. Here I evaluate the robustness of Hill's model to extreme patterns of reproductive success, whose effects have not been previously examined: (1) very strong reproductive skew; (2) strong temporal autocorrelations in individual reproductive success; and (3) strong covariance of individual reproduction and survival. Genetic drift (loss of heterozygosity and increase in allele frequency variance) was simulated in age-structured populations using methods that generated no autocorrelations or covariances (Model NoCor); or created strong positive (Model Positive) or strong negative (Model Negative) temporal autocorrelations in reproduction and covariances between reproduction and survival. Compared to Model NoCor, the other models led to greatly elevated or reduced [Formula: see text], and hence greatly reduced or elevated Ne, respectively. A new index is introduced (ρα,α+), which is the correlation between (1) the number of offspring produced by each individual at the age at maturity (α), and (2) the total number of offspring produced during the rest of their lifetimes. Mean ρα,α+ was ≈0 under Model NoCor, strongly positive under Model Positive, and strongly negative under Model Negative. Even under the most extreme reproductive scenarios in Models Positive and Negative, when [Formula: see text] was calculated from the realized population pedigree and used to calculate Ne in Hill's model, the result accurately predicted the rate of genetic drift in simulated populations. These results held for scenarios where age-specific reproductive skew was random (variance ≈ mean) and highly overdispersed (variance up to 20 times the mean). Collectively, these results are good news for researchers as they demonstrate the robustness of Hill's model even in extreme reproductive scenarios.
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Affiliation(s)
- Robin S Waples
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA.
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16
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Whitney JL, Coleman RR, Deakos MH. Genomic evidence indicates small island-resident populations and sex-biased behaviors of Hawaiian reef Manta Rays. BMC Ecol Evol 2023; 23:31. [PMID: 37422622 PMCID: PMC10329317 DOI: 10.1186/s12862-023-02130-0] [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: 11/19/2022] [Accepted: 06/07/2023] [Indexed: 07/10/2023] Open
Abstract
BACKGROUND Reef manta rays (Mobula alfredi) are globally distributed in tropical and subtropical seas. Their life history traits (slow growth, late maturity, low reproductive output) make them vulnerable to perturbations and therefore require informed management strategies. Previous studies have reported wide-spread genetic connectivity along continental shelves suggesting high gene flow along continuous habitats spanning hundreds of kilometers. However, in the Hawaiian Islands, tagging and photo-identification evidence suggest island populations are isolated despite proximity, a hypothesis that has not yet been evaluated with genetic data. RESULTS This island-resident hypothesis was tested by analyzing whole mitogenome haplotypes and 2048 nuclear single nucleotide polymorphisms (SNPs) between M. alfredi (n = 38) on Hawai'i Island and Maui Nui (the 4-island complex of Maui, Moloka'i, Lāna'i and Kaho'olawe). Strong divergence in the mitogenome (ΦST = 0.488) relative to nuclear genome-wide SNPs (neutral FST = 0.003; outlier FST = 0.186), and clustering of mitochondrial haplotypes among islands provides robust evidence that female reef manta rays are strongly philopatric and do not migrate between these two island groups. Combined with restricted male-mediated migration, equivalent to a single male moving between islands every 2.2 generations (~ 64 years), we provide evidence these populations are significantly demographically isolated. Estimates of contemporary effective population size (Ne) are 104 (95% CI: 99-110) in Hawai'i Island and 129 (95% CI: 122-136) in Maui Nui. CONCLUSIONS Concordant with evidence from photo identification and tagging studies, these genetic results indicate reef manta rays in Hawai'i have small, genetically-isolated resident island populations. We hypothesize that due to the Island Mass Effect, large islands provide sufficient resources to support resident populations, thereby making crossing deep channels separating island groups unnecessary. Small effective population size, low genetic diversity, and k-selected life history traits make these isolated populations vulnerable to region-specific anthropogenic threats, which include entanglement, boat strikes, and habitat degradation. The long-term persistence of reef manta rays in the Hawaiian Islands will require island-specific management strategies.
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Affiliation(s)
- Jonathan L Whitney
- National Oceanic and Atmospheric Administration, Pacific Islands Fisheries Science Center, Honolulu, Hawai'i, USA.
| | - Richard R Coleman
- Department of Marine Biology and Ecology, Rosenstiel School of Marine, Atmospheric, and Earth Sciences, University of Miami, Miami, FL, USA
| | - Mark H Deakos
- Hawai'i Association for Marine Education and Research, Lahaina, Maui, Hawai'i, USA
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17
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Delord C, Petit EJ, Blanchet S, Longin G, Rinaldo R, Vigouroux R, Roussel JM, Le Bail PY, Launey S. Contrasts in riverscape patterns of intraspecific genetic variation in a diverse Neotropical fish community of high conservation value. Heredity (Edinb) 2023; 131:1-14. [PMID: 37185615 PMCID: PMC10313816 DOI: 10.1038/s41437-023-00616-7] [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: 04/11/2022] [Revised: 04/03/2023] [Accepted: 04/03/2023] [Indexed: 05/17/2023] Open
Abstract
Spatial patterns of genetic variation compared across species provide information about the predictability of genetic diversity in natural populations, and areas requiring conservation measures. Due to their remarkable fish diversity, rivers in Neotropical regions are ideal systems to confront theory with observations and would benefit greatly from such approaches given their increasing vulnerability to anthropogenic pressures. We used SNP data from 18 fish species with contrasting life-history traits, co-sampled across 12 sites in the Maroni- a major river system from the Guiana Shield -, to compare patterns of intraspecific genetic variation and identify their underlying drivers. Analyses of covariance revealed a decrease in genetic diversity as distance from the river outlet increased for 5 of the 18 species, illustrating a pattern commonly observed in riverscapes for species with low-to-medium dispersal abilities. However, the mean within-site genetic diversity was lowest in the two easternmost tributaries of the Upper Maroni and around an urbanized location downstream, indicating the need to address the potential influence of local pressures in these areas, such as gold mining or fishing. Finally, the relative influence of isolation by stream distance, isolation by discontinuous river flow, and isolation by spatial heterogeneity in effective size on pairwise genetic differentiation varied across species. Species with similar dispersal and reproductive guilds did not necessarily display shared patterns of population structure. Increasing the knowledge of specific life history traits and ecological requirements of fish species in these remote areas should help further understand factors that influence their current patterns of genetic variation.
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Affiliation(s)
- Chrystelle Delord
- DECOD (Ecosystem Dynamics and Sustainability), INRAE, Institut Agro, IFREMER, 35042, Rennes, France.
- HYDRECO Guyane SARL, Laboratoire-Environnement de Petit Saut, 97310, Kourou, France.
- UMR MARBEC, Univ. Montpellier, IRD, Ifremer, CNRS, Sète, France.
| | - Eric J Petit
- DECOD (Ecosystem Dynamics and Sustainability), INRAE, Institut Agro, IFREMER, 35042, Rennes, France
| | - Simon Blanchet
- CNRS, Station d'Ecologie Théorique et Expérimentale, UAR, 2029, Moulis, France
| | | | | | - Régis Vigouroux
- HYDRECO Guyane SARL, Laboratoire-Environnement de Petit Saut, 97310, Kourou, France
| | - Jean-Marc Roussel
- DECOD (Ecosystem Dynamics and Sustainability), INRAE, Institut Agro, IFREMER, 35042, Rennes, France
| | | | - Sophie Launey
- DECOD (Ecosystem Dynamics and Sustainability), INRAE, Institut Agro, IFREMER, 35042, Rennes, France
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18
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Ryman N, Laikre L, Hössjer O. Variance effective population size is affected by census size in sub-structured populations. Mol Ecol Resour 2023. [PMID: 37122118 DOI: 10.1111/1755-0998.13804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 04/06/2023] [Accepted: 04/12/2023] [Indexed: 05/02/2023]
Abstract
Measurement of allele frequency shifts between temporally spaced samples has long been used for assessment of effective population size (Ne ), and this 'temporal method' provides estimates of Ne referred to as variance effective size (NeV ). We show that NeV of a local population that belongs to a sub-structured population (a metapopulation) is determined not only by genetic drift and migration rate (m), but also by the census size (Nc ). The realized NeV of a local population can either increase or decrease with increasing m, depending on the relationship between Ne and Nc in isolation. This is shown by explicit mathematical expressions for the factors affecting NeV derived for an island model of migration. We verify analytical results using high-resolution computer simulations, and show that the phenomenon is not restricted to the island model migration pattern. The effect of Nc on the realized NeV of a local subpopulation is most pronounced at high migration rates. We show that Nc only affects local NeV , whereas NeV for the metapopulation as a whole, inbreeding (NeI ), and linkage disequilibrium (NeLD ) effective size are all independent of Nc . Our results provide a possible explanation to the large variation of Ne /Nc ratios reported in the literature, where Ne is frequently estimated by NeV . They are also important for the interpretation of empirical Ne estimates in genetic management where local NeV is often used as a substitute for inbreeding effective size, and we suggest an increased focus on metapopulation NeV as a proxy for NeI .
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Affiliation(s)
- Nils Ryman
- Division of Population Genetics, Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Linda Laikre
- Division of Population Genetics, Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Ola Hössjer
- Department of Mathematics, Stockholm University, Stockholm, Sweden
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19
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Brooks GC, Wendt A, Haas CA, Roberts JH. Comparing estimates of census and effective population size in an endangered amphibian. Anim Conserv 2023. [DOI: 10.1111/acv.12871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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20
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Kitanishi S, Kondou T, Takahashi H, Takeshita N, Nagata S, Edo K. Recent reduction of genetic diversity in markless form of the red-spotted masu salmon Oncorhynchus masou ishikawae in the Ono River, Kyushu, Japan. CONSERV GENET 2023. [DOI: 10.1007/s10592-023-01515-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2023]
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21
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Conservation Genetics of Lake Sturgeon (Acipenser fulvescens): Nuclear Phylogeography Drives Contemporary Patterns of Genetic Structure and Diversity. DIVERSITY 2023. [DOI: 10.3390/d15030385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Sustainable management of exploited and endangered species is facilitated by knowledge of their geographic genetic structure. Lake sturgeon (Acipenser fulvescens) epitomizes both categories, but genetic information has largely been limited to the Laurentian Great Lakes basin. We assessed the hierarchical geographic genetic structure of lake sturgeon across their Canadian range using a variation at 14 microsatellite loci. Observed patterns showed evidence of two ancestral groups which originated from Mississippian and Missourian glacial refugia. Coalescent analysis indicates the two lineages most recently shared common ancestry during the late Pleistocene and were likely isolated by the late Wisconsinan ice advance, with subsequent interpopulation divergences within each lineage reflecting their reciprocal isolation as glacial meltwaters receded. Hierarchical patterns of genetic relationships among contemporary populations largely reflect colonization histories and connections within primary and secondary watersheds. Populations in western Canada showed strong similarities based on their shared Missourian origins and colonization from glacial Lake Agassiz. By contrast, populations in the Great Lakes–St. Lawrence River drainage were largely founded from a Mississippian source. Sturgeon populations in northern parts of Ontario and Quebec showed evidence of mixed ancestry from secondary contact between the two refugial groups through Holocene meltwater lakes. Within major watersheds, the strong similarity among geographically separate populations reflects their shared ancestry during postglacial colonization. The general lack of structure within major river systems highlights historically continuous habitat (connectivity) and gene flow rather than contemporary barriers (dams). These data highlight the importance of Quaternary and prehistoric events on patterns of genetic diversity and divergence within and among contemporary populations, as well as the importance of these populations for conserving the species’ evolutionary legacy.
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22
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Gargiulo R, Waples RS, Grow AK, Shefferson RP, Viruel J, Fay MF, Kull T. Effective population size in a partially clonal plant is not predicted by the number of genetic individuals. Evol Appl 2023; 16:750-766. [PMID: 36969138 PMCID: PMC10033856 DOI: 10.1111/eva.13535] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 11/22/2022] [Accepted: 02/02/2023] [Indexed: 02/23/2023] Open
Abstract
Estimating effective population size (N e) is important for theoretical and practical applications in evolutionary biology and conservation. Nevertheless, estimates of N e in organisms with complex life-history traits remain scarce because of the challenges associated with estimation methods. Partially clonal plants capable of both vegetative (clonal) growth and sexual reproduction are a common group of organisms for which the discrepancy between the apparent number of individuals (ramets) and the number of genetic individuals (genets) can be striking, and it is unclear how this discrepancy relates to N e. In this study, we analysed two populations of the orchid Cypripedium calceolus to understand how the rate of clonal versus sexual reproduction affected N e. We genotyped >1000 ramets at microsatellite and SNP loci, and estimated contemporary N e with the linkage disequilibrium method, starting from the theoretical expectation that variance in reproductive success among individuals caused by clonal reproduction and by constraints on sexual reproduction would lower N e. We considered factors potentially affecting our estimates, including different marker types and sampling strategies, and the influence of pseudoreplication in genomic data sets on N e confidence intervals. The magnitude of N e/N ramets and N e/N genets ratios we provide may be used as reference points for other species with similar life-history traits. Our findings demonstrate that N e in partially clonal plants cannot be predicted based on the number of genets generated by sexual reproduction, because demographic changes over time can strongly influence N e. This is especially relevant in species of conservation concern in which population declines may not be detected by only ascertaining the number of genets.
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Affiliation(s)
| | - Robin S. Waples
- NOAA Fisheries, Northwest Fisheries Science Center Seattle Washington USA
- University of Washington Seattle Washington USA
| | - Adri K. Grow
- Department of Biological Sciences Smith College Northampton Massachusetts USA
| | | | | | - Michael F. Fay
- Royal Botanic Gardens, Kew Richmond UK
- School of Biological Sciences University of Western Australia Crawley Western Australia Australia
| | - Tiiu Kull
- Estonian University of Life Sciences Tartu Estonia
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23
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Fitz KS, Montes HR, Thompson DM, Pinsky ML. Isolation-by-distance and isolation-by-oceanography in Maroon Anemonefish ( Amphiprion biaculeatus). Evol Appl 2023; 16:379-392. [PMID: 36793687 PMCID: PMC9923474 DOI: 10.1111/eva.13448] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 05/27/2022] [Accepted: 07/07/2022] [Indexed: 11/29/2022] Open
Abstract
Obtaining dispersal estimates for a species is key to understanding local adaptation and population dynamics and to implementing conservation actions. Genetic isolation-by-distance (IBD) patterns can be used for estimating dispersal, and these patterns are especially useful for marine species in which few other methods are available. In this study, we genotyped coral reef fish (Amphiprion biaculeatus) at 16 microsatellite loci across eight sites across 210 km in the central Philippines to generate fine-scale estimates of dispersal. All sites except for one followed IBD patterns. Using IBD theory, we estimated a larval dispersal kernel spread of 8.9 km (95% confidence interval of 2.3-18.4 km). Genetic distance to the remaining site correlated strongly with the inverse probability of larval dispersal from an oceanographic model. Ocean currents were a better explanation for genetic distance at large spatial extents (sites greater than 150 km apart), while geographic distance remained the best explanation for spatial extents less than 150 km. Our study demonstrates the utility of combining IBD patterns with oceanographic simulations to understand connectivity in marine environments and to guide marine conservation strategies.
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Affiliation(s)
- Kyra S Fitz
- Department of Ecology, Evolution and Natural Resources Rutgers University New Brunswick New Jersey USA
| | - Humberto R Montes
- Institute of Tropical Ecology and Environmental Management Visayas State University Baybay City Philippines
| | - Diane M Thompson
- Department of Geosciences University of Arizona Tucson Arizona USA
| | - Malin L Pinsky
- Department of Ecology, Evolution and Natural Resources Rutgers University New Brunswick New Jersey USA
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24
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Madsen T, Ujvari B, Bauwens D, Gruber B, Georges A, Klaassen M. Polyandry and non-random fertilisation maintain long-term genetic diversity in an isolated island population of adders (Vipera berus). Heredity (Edinb) 2023; 130:64-72. [PMID: 36474024 PMCID: PMC9905584 DOI: 10.1038/s41437-022-00578-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 11/09/2022] [Accepted: 11/12/2022] [Indexed: 12/12/2022] Open
Abstract
Conservation genetic theory suggests that small and isolated populations should be subject to reduced genetic diversity i.e., heterozygosity and allelic diversity. Our 34 years study of an isolated island population of adders (Vipera berus) in southern Sweden challenges this notion. Despite a lack of gene flow and a yearly mean estimated reproductive adult population size of only 65 adult adders (range 12-171), the population maintains high levels of heterozygosity and allelic diversity similar to that observed in two mainland populations. Even a 14-year major "bottleneck" i.e., a reduction in adult adder numbers, encompassing at least four adder generations, did not result in any reduction in the island adders' heterozygosity and allelic diversity. Female adders are polyandrous, and fertilisation is non-random, which our empirical data and modelling suggest are underpinning the maintenance of the population's high level of heterozygosity. Our empirical results and subsequent modelling suggest that the positive genetic effects of polyandry in combination with non-random fertilisation, often overlooked in conservation genetic analyses, deserve greater consideration when predicting long-term survival of small and isolated populations.
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Affiliation(s)
- Thomas Madsen
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, 3217, Australia.
| | - Beata Ujvari
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, 3217, Australia
| | - Dirk Bauwens
- Department of Biology, Laboratory of Functional Morphology, University of Antwerp, Wilrijk, Belgium
| | - Bernd Gruber
- Institute for Applied Ecology, University of Canberra, Canberra, ACT, 2601, Australia
| | - Arthur Georges
- Institute for Applied Ecology, University of Canberra, Canberra, ACT, 2601, Australia
| | - Marcel Klaassen
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, 3217, Australia
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25
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Stojanovic D, McLennan E, Olah G, Cobden M, Heinsohn R, Manning AD, Alves F, Hogg C, Rayner L. Reproductive skew in a Vulnerable bird favors breeders that monopolize nest cavities. Anim Conserv 2023. [DOI: 10.1111/acv.12855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- D. Stojanovic
- Fenner School of Environment and Society Australian National University Canberra Australia
| | - E. McLennan
- School of Life & Environmental Sciences The University of Sydney Sydney New South Wales Australia
| | - G. Olah
- Fenner School of Environment and Society Australian National University Canberra Australia
| | - M. Cobden
- Fenner School of Environment and Society Australian National University Canberra Australia
| | - R. Heinsohn
- Fenner School of Environment and Society Australian National University Canberra Australia
| | - A. D. Manning
- Fenner School of Environment and Society Australian National University Canberra Australia
| | - F. Alves
- Fenner School of Environment and Society Australian National University Canberra Australia
| | - C. Hogg
- School of Life & Environmental Sciences The University of Sydney Sydney New South Wales Australia
| | - L. Rayner
- ACT Parks and Conservation Service, Australian Capital Territory Government Canberra Australia
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26
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Pinzari CA, Bellinger MR, Price D, Bonaccorso FJ. Genetic diversity, structure, and effective population size of an endangered, endemic hoary bat, 'ōpe'ape'a, across the Hawaiian Islands. PeerJ 2023; 11:e14365. [PMID: 36718450 PMCID: PMC9884036 DOI: 10.7717/peerj.14365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 10/19/2022] [Indexed: 01/26/2023] Open
Abstract
Island bat species are disproportionately at risk of extinction, and Hawai'i's only native terrestrial land mammal, the Hawaiian hoary bat (Lasiurus semotus) locally known as 'ōpe'ape'a, is no exception. To effectively manage this bat species with an archipelago-wide distribution, it is important to determine the population size on each island and connectivity between islands. We used 18 nuclear microsatellite loci and one mitochondrial gene from 339 individuals collected from 1988-2020 to evaluate genetic diversity, population structure and estimate effective population size on the Islands of Hawai'i, Maui, O'ahu, and Kaua'i. Genetic differentiation occurred between Hawai'i and Maui, both of which were differentiated from O'ahu and Kaua'i. The population on Maui presents the greatest per-island genetic diversity, consistent with their hypothesized status as the original founding population. A signature of isolation by distance was detected between islands, with contemporary migration analyses indicating limited gene flow in recent generations, and male-biased sex dispersal within Maui. Historical and long-term estimates of genetic effective population sizes were generally larger than contemporary estimates, although estimates of contemporary genetic effective population size lacked upper bounds in confidence intervals for Hawai'i and Kaua'i. Contemporary genetic effective population sizes were smaller on O'ahu and Maui. We also detected evidence of past bottlenecks on all islands with the exception of Hawai'i. Our study provides population-level estimates for the genetic diversity and geographic structure of 'ōpe'ape'a, that could be used by agencies tasked with wildlife conservation in Hawai'i.
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Affiliation(s)
- Corinna A. Pinzari
- Tropical Conservation Biology and Environmental Science Graduate Program, University of Hawaiʻi at Hilo, Hilo, Hawaiʻi, United States of America,Hawaiʻi Cooperative Studies Unit, University of Hawaiʻi at Hilo, Hawaiʻi National Park, Hawaiʻi, United States of America
| | - M. Renee Bellinger
- Tropical Conservation Biology and Environmental Science Graduate Program, University of Hawaiʻi at Hilo, Hilo, Hawaiʻi, United States of America,Hawaiʻi Cooperative Studies Unit, University of Hawaiʻi at Hilo, Hawaiʻi National Park, Hawaiʻi, United States of America,Pacific Island Ecosystems Research Center, U.S. Geological Survey, Hawaiʻi National Park, Hawaiʻi, United States of America
| | - Donald Price
- Tropical Conservation Biology and Environmental Science Graduate Program, University of Hawaiʻi at Hilo, Hilo, Hawaiʻi, United States of America,School of Life Sciences, University of Nevada - Las Vegas, Las Vegas, NV, United States of America
| | - Frank J. Bonaccorso
- Pacific Island Ecosystems Research Center, U.S. Geological Survey, Hawaiʻi National Park, Hawaiʻi, United States of America
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27
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Appraising the Genetic Makeup of an Allochthonous Southern Pike Population: An Opportunity to Predict the Evolution of Introgressive Hybridization in Isolated Populations? Animals (Basel) 2023; 13:ani13030380. [PMID: 36766269 PMCID: PMC9913590 DOI: 10.3390/ani13030380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 01/24/2023] Open
Abstract
Biological invasions are a major threat to the conservation of biodiversity, as invasive species affect native biota through competition, predation, pathogen introduction, habitat alteration, and hybridisation. The present study focuses on a southern pike population, Esox cisalpinus (Teleostei: Esocidae), that has been introduced outside the species' native range. Using microsatellite markers, this study's objective was to gather baseline genetic information and assess the presence of hybrids between this species and E. lucius in the introduced population. The resulting estimates of genetic diversity and effective population size are comparable to those observed in the species' native range. Although different methods yield contrasting and uncertain evidence regarding introgressive hybridization, the presence of late-generation hybrids cannot be completely ruled out. Large numbers of breeders as well as multiple introductions of genetically divergent cohorts and introgressive hybridisation may explain the high genetic diversity of this recently introduced southern pike population. The present study issues a warning that the conservation of southern pike' introgressive hybridisation between northern and southern pike might be underestimated. The genetic information gathered herein may unravel the origin, number of introduction events, and evolutionary trajectory of the introduced population. This information may help us understand the evolution of introgressive hybridisation in the southern pike's native areas.
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Bernos TA, Avlijaš S, Hill J, Morissette O, Ricciardi A, Mandrak NE, Jeffries KM. Genetic diversity and structure of a recent fish invasion: Tench ( Tinca tinca) in eastern North America. Evol Appl 2023; 16:173-188. [PMID: 36699124 PMCID: PMC9850014 DOI: 10.1111/eva.13520] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 10/22/2022] [Accepted: 12/02/2022] [Indexed: 01/20/2023] Open
Abstract
Introduced and geographically expanding populations experience similar eco-evolutionary challenges, including founder events, genetic bottlenecks, and novel environments. Theory predicts that reduced genetic diversity resulting from such phenomena limits the success of introduced populations. Using 1900 SNPs obtained from restriction-site-associated DNA sequencing, we evaluated hypotheses related to the invasion history and connectivity of an invasive population of Tench (Tinca tinca), a Eurasian freshwater fish that has been expanding geographically in eastern North America for three decades. Consistent with the reported history of a single introduction event, our findings suggest that multiple introductions from distinct genetic sources are unlikely as Tench had a small effective population size (~114 [95% CI = 106-123] individuals), no strong population subdivision across time and space, and evidence of a recent genetic bottleneck. The large genetic neighbourhood size (220 km) and weak within-population genetic substructure suggested high connectivity across the invaded range, despite the relatively large area occupied. There was some evidence for a small decay in genetic diversity as the species expanded northward, but not southward, into new habitats. As eradicating the species within a ~112 km radius would be necessary to prevent recolonization, eradicating Tench is likely not feasible at watershed-and possibly local-scales. Management should instead focus on reducing abundance in priority conservation areas to mitigate adverse impacts. Our study indicates that introduced populations can thrive and exhibit relatively high levels of genetic diversity despite severe bottlenecks (<1.5% of the ancestral effective population size) and suggests that landscape heterogeneity and population demographics can generate variability in spatial patterns of genetic diversity within a single range expansion.
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Affiliation(s)
- Thaïs A. Bernos
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoOntarioCanada
- Department of Biological SciencesUniversity of Toronto ScarboroughScarboroughOntarioCanada
| | - Sunčica Avlijaš
- Redpath MuseumMcGill UniversityMontrealQuébecCanada
- Department of BiologyMcGill UniversityMontrealQuébecCanada
| | - Jaclyn Hill
- Maurice Lamontagne InstituteFisheries and Oceans CanadaMont‐JoliQuébecCanada
| | - Olivier Morissette
- Département des Sciences FondamentalesUniversité du Québec à ChicoutimiChicoutimiQuébecCanada
| | | | - Nicholas E. Mandrak
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoOntarioCanada
| | - Kenneth M. Jeffries
- Department of Biological SciencesUniversity of ManitobaWinnipegManitobaCanada
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29
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Kimble SJA, Unger SD, Williams RN. Genetically derived effective population size estimates of herpetofaunal species should be used with caution. J Wildl Manage 2022. [DOI: 10.1002/jwmg.22340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | - Shem D. Unger
- Department of Biology Wingate University Wingate NC 28174 USA
| | - Rod N. Williams
- Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA
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30
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Lim QL, Yong CSY, Ng WL, Ismail A, Rovie-Ryan JJ, Rosli N, Inoue-Murayama M, Annavi G. Population genetic structure of wild Malayan tapirs (Tapirus indicus) in Peninsular Malaysia revealed by nine cross-species microsatellite markers. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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31
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Hoey JA, Able KW, Pinsky ML. Genetic decline and recovery of a demographically rebuilt fishery species. Mol Ecol 2022; 31:5684-5698. [PMID: 36114805 PMCID: PMC9828022 DOI: 10.1111/mec.16697] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/09/2022] [Accepted: 09/15/2022] [Indexed: 01/13/2023]
Abstract
The demographic history of a population is important for conservation and evolution, but this history is unknown for many populations. Methods that use genomic data have been developed to infer demography, but they can be challenging to implement and interpret, particularly for large populations. Thus, understanding if and when genetic estimates of demography correspond to true population history is important for assessing the performance of these genetic methods. Here, we used double-digest restriction-site associated DNA (ddRAD) sequencing data from archived collections of larval summer flounder (Paralichthys dentatus, n = 279) from three cohorts (1994-1995, 1997-1998 and 2008-2009) along the U.S. East coast to examine how contemporary effective population size and genetic diversity responded to changes in abundance in a natural population. Despite little to no detectable change in genetic diversity, coalescent-based demographic modelling from site frequency spectra revealed that summer flounder effective population size declined dramatically in the early 1980s. The timing and direction of change corresponded well with the observed decline in spawning stock census abundance in the late 1980s from independent fish surveys. Census abundance subsequently recovered and achieved the prebottleneck size. Effective population size also grew following the bottleneck. Our results for summer flounder demonstrate that genetic sampling and site frequency spectra can be useful for detecting population dynamics, even in species with large effective sizes.
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Affiliation(s)
- Jennifer A. Hoey
- Ecology, Evolution, & Natural ResourcesRutgers UniversityNew BrunswickNew JerseyUSA,Institute for Biodiversity Science and SustainabilityCalifornia Academy of SciencesSan FranciscoCaliforniaUSA
| | - Kenneth W. Able
- Marine Field Station, Department of Marine and Coastal Sciences, Rutgers UniversityTuckertonNew JerseyUSA
| | - Malin L. Pinsky
- Ecology, Evolution, & Natural ResourcesRutgers UniversityNew BrunswickNew JerseyUSA
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Forester BR, Murphy M, Mellison C, Petersen J, Pilliod DS, Van Horne R, Harvey J, Funk WC. Genomics-informed delineation of conservation units in a desert amphibian. Mol Ecol 2022; 31:5249-5269. [PMID: 35976166 PMCID: PMC9804278 DOI: 10.1111/mec.16660] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 07/28/2022] [Indexed: 01/05/2023]
Abstract
Delineating conservation units (CUs, e.g., evolutionarily significant units, ESUs, and management units, MUs) is critical to the recovery of declining species because CUs inform both listing status and management actions. Genomic data have strengths and limitations in informing CU delineation and related management questions in natural systems. We illustrate the value of using genomic data in combination with landscape, dispersal and occupancy data to inform CU delineation in Nevada populations of the Great Basin Distinct Population Segment of the Columbia spotted frog (Rana luteiventris). R. luteiventris occupies naturally fragmented aquatic habitats in this xeric region, but beaver removal, climate change and other factors have put many of these populations at high risk of extirpation without management intervention. We addressed three objectives: (i) assessing support for ESUs within Nevada; (ii) evaluating and revising, if warranted, the current delineation of MUs; and (iii) evaluating genetic diversity, effective population size, adaptive differentiation and functional connectivity to inform ongoing management actions. We found little support for ESUs within Nevada but did identify potential revisions to MUs based on unique landscape drivers of connectivity that distinguish these desert populations from those in the northern portion of the species range. Effective sizes were uniformly small, with low genetic diversity and weak signatures of adaptive differentiation. Our findings suggest that management actions, including translocations and genetic rescue, might be warranted. Our study illustrates how a carefully planned genetic study, designed to address priority management goals that include CU delineation, can provide multiple insights to inform conservation action.
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Affiliation(s)
- Brenna R Forester
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Melanie Murphy
- Department of Ecosystem Science and Management, Program in Ecology, University of Wyoming, Laramie, WY, USA
| | | | | | - David S Pilliod
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Boise, ID, USA
| | | | | | - W Chris Funk
- Department of Biology, Colorado State University, Fort Collins, CO, USA.,Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
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33
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Clarke SH, McCracken GR, Humphries S, Ruzzante D, Grant JWA, Fraser DJ. Demographic resilience of brook trout populations subjected to experimental size‐selective. Evol Appl 2022; 15:1792-1805. [DOI: 10.1111/eva.13478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 11/29/2022] Open
Affiliation(s)
| | | | - Shelley Humphries
- Lake Louise, Yoho, and Kootenay Field Unit, Parks Canada Radium Hot Springs British Columbia Canada
| | | | | | - Dylan J. Fraser
- Department of Biology Concordia University Montreal Quebec Canada
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34
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Hemstrom W, Dauwalter D, Peacock M, Leasure D, Wenger S, Miller M, Neville. Population genomic monitoring provides insight into conservation status but no correlation with demographic estimates of extinction risk in a threatened trout. Evol Appl 2022; 15:1449-1468. [PMID: 36187186 PMCID: PMC9488680 DOI: 10.1111/eva.13473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 08/12/2022] [Indexed: 12/03/2022] Open
Abstract
The current extinction crisis requires effective assessment and monitoring tools. Genetic approaches are appealing given the relative ease of field sampling required to estimate genetic diversity characteristics assumed related to population size, evolutionary potential, and extinction risk, and to evaluate hybridization with non‐native species simultaneously. However, linkages between population genetic metrics of diversity from survey‐style field collections and demographic estimates of population size and extinction risk are still in need of empirical examples, especially for remotely distributed species of conservation concern where the approach might be most beneficial. We capitalized on an exceptional opportunity to evaluate congruence between genetic diversity metrics and demographic‐based estimates of abundance and extinction risk from a comprehensive Multiple Population Viability Analysis (MPVA) in a threatened fish, the Lahontan cutthroat trout (LCT). We sequenced non‐native trout reference samples and recently collected and archived tissue samples of most remaining populations of LCT (N = 60) and estimated common genetic assessment metrics, predicting minimal hybridization with non‐native trout, low diversity, and declining diversity over time. We further hypothesized genetic metrics would correlate positively with MPVA‐estimated abundance and negatively with extinction probability. We uncovered several instances of hybridization that pointed to immediate management needs. After removing hybridized individuals, cautious interpretation of low effective population sizes (2–63) suggested reduced evolutionary potential for many LCT populations. Other genetic metrics did not decline over time nor correlate with MPVA‐based estimates of harmonic mean abundance or 30‐year extinction probability. Our results demonstrate benefits of genetic monitoring for efficiently detecting hybridization and, though genetic results were disconnected from demographic assessment of conservation status, they suggest reduced evolutionary potential and likely a higher conservation risk than currently recognized for this threatened fish. We emphasize that genetic information provides essential complementary insight, in addition to demographic information, for evaluating species status.
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Affiliation(s)
- W. Hemstrom
- Department of Animal Science University of California Davis California U.S.A
| | | | - M. Peacock
- Department of Biology University of Nevada Reno Nevada U.S.A
| | - D. Leasure
- WorldPop, Geography and Environmental Science University of Southampton Southampton United Kingdom
| | - S. Wenger
- Odum School of Ecology University of Georgia Athens GA U.S.A
| | - M. Miller
- Department of Animal Science University of California Davis California U.S.A
| | - Neville
- Science Program, Trout Unlimited Boise ID U.S.A
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35
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Marshall IR, Brauer CJ, Wedderburn SD, Whiterod NS, Hammer MP, Barnes TC, Attard CRM, Möller LM, Beheregaray LB. Longitudinal monitoring of neutral and adaptive genomic diversity in a reintroduction. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2022; 36:e13889. [PMID: 35023224 DOI: 10.1111/cobi.13889] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 12/16/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
Restoration programs in the form of ex-situ breeding combined with reintroductions are becoming critical to counteract demographic declines and species losses. Such programs are increasingly using genetic management to improve conservation outcomes. However, the lack of long-term monitoring of genetic indicators following reintroduction prevents assessments of the trajectory and persistence of reintroduced populations. We carried out an extensive monitoring program in the wild for a threatened small-bodied fish (southern pygmy perch, Nannoperca australis) to assess the long-term genomic effects of its captive breeding and reintroduction. The species was rescued prior to its extirpation from the terminal lakes of Australia's Murray-Darling Basin, and then used for genetically informed captive breeding and reintroductions. Subsequent annual or biannual monitoring of abundance, fitness, and occupancy over a period of 11 years, combined with postreintroduction genetic sampling, revealed survival and recruitment of reintroduced fish. Genomic analyses based on data from the original wild rescued, captive born, and reintroduced cohorts revealed low inbreeding and strong maintenance of neutral and candidate adaptive genomic diversity across multiple generations. An increasing trend in the effective population size of the reintroduced population was consistent with field monitoring data in demonstrating successful re-establishment of the species. This provides a rare empirical example that the adaptive potential of a locally extinct population can be maintained during genetically informed ex-situ conservation breeding and reintroduction into the wild. Strategies to improve biodiversity restoration via ex-situ conservation should include genetic-based captive breeding and longitudinal monitoring of standing genomic variation in reintroduced populations.
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Affiliation(s)
- Imogen R Marshall
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Chris J Brauer
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Scotte D Wedderburn
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Nick S Whiterod
- Aquasave-Nature Glenelg Trust, Victor Harbor, South Australia, Australia
| | - Michael P Hammer
- Natural Sciences, Museum and Art Gallery of the Northern Territory, Darwin, Northern Territory, Australia
| | - Thomas C Barnes
- New South Wales Department of Primary Industries, Port Stephens Fisheries Institute, Nelson Bay, New South Wales, Australia
- Institute of Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Catherine R M Attard
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Luciana M Möller
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Luciano B Beheregaray
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
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36
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Naaykens T, D’Aloia CC. Isolation‐by‐distance and genetic parentage analysis provide similar larval dispersal estimates. Mol Ecol 2022; 31:3072-3082. [DOI: 10.1111/mec.16465] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 02/10/2022] [Accepted: 03/30/2022] [Indexed: 11/28/2022]
Affiliation(s)
- T. Naaykens
- Department of Biological Sciences University of New Brunswick – Saint John 100 Tucker Park Road NB E2L 4L5 Canada
| | - C. C. D’Aloia
- Department of Biology University of Toronto Mississauga 3359 Mississauga Road Mississauga ON L5L 1C6 Canada
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37
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Pilger TJ, Gido KB, Propst DL, Whitney JE, Turner TF. Demography predicts genetic effective size in a desert stream fish community. Am Nat 2022; 200:275-291. [DOI: 10.1086/720208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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38
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Contrasting genetic trajectories of endangered and expanding red fox populations in the western U.S. Heredity (Edinb) 2022; 129:123-136. [PMID: 35314789 PMCID: PMC9338314 DOI: 10.1038/s41437-022-00522-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 12/04/2022] Open
Abstract
As anthropogenic disturbances continue to drive habitat loss and range contractions, the maintenance of evolutionary processes will increasingly require targeting measures to the population level, even for common and widespread species. Doing so requires detailed knowledge of population genetic structure, both to identify populations of conservation need and value, as well as to evaluate suitability of potential donor populations. We conducted a range-wide analysis of the genetic structure of red foxes in the contiguous western U.S., including a federally endangered distinct population segment of the Sierra Nevada subspecies, with the objectives of contextualizing field observations of relative scarcity in the Pacific mountains and increasing abundance in the cold desert basins of the Intermountain West. Using 31 autosomal microsatellites, along with mitochondrial and Y-chromosome markers, we found that populations of the Pacific mountains were isolated from one another and genetically depauperate (e.g., estimated Ne range = 3–9). In contrast, red foxes in the Intermountain regions showed relatively high connectivity and genetic diversity. Although most Intermountain red foxes carried indigenous western matrilines (78%) and patrilines (85%), the presence of nonindigenous haplotypes at lower elevations indicated admixture with fur-farm foxes and possibly expanding midcontinent populations as well. Our findings suggest that some Pacific mountain populations could likely benefit from increased connectivity (i.e., genetic rescue) but that nonnative admixture makes expanding populations in the Intermountain basins a non-ideal source. However, our results also suggest contact between Pacific mountain and Intermountain basin populations is likely to increase regardless, warranting consideration of risks and benefits of proactive measures to mitigate against unwanted effects of Intermountain gene flow.
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39
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Genomic insights into the historical and contemporary demographics of the grey reef shark. Heredity (Edinb) 2022; 128:225-235. [PMID: 35296830 PMCID: PMC8987070 DOI: 10.1038/s41437-022-00514-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 02/11/2022] [Accepted: 02/13/2022] [Indexed: 11/08/2022] Open
Abstract
Analyses of genetic diversity can shed light on both the origins of biodiversity hotspots, as well as the conservation status of species that are impacted by human activities. With these objectives, we assembled a genomic dataset of 14,935 single nucleotide polymorphisms from 513 grey reef sharks (Carcharhinus amblyrhynchos) sampled across 17 locations in the tropical Indo-Pacific. We analysed geographic variation in genetic diversity, estimated ancient and contemporary effective population size (Ne) across sampling locations (using coalescent and linkage disequilibrium methods) and modelled the history of gene flow between the Coral Triangle and the Coral Sea. Genetic diversity decreased with distance away from the Coral Triangle and north-western Australia, implying that C. amblyrhynchos may have originated in this region. Increases in Ne were detected across almost all sampling locations 40,000-90,000 generations ago (approximately 0.6-1.5 mya, given an estimated generation time of 16.4 years), suggesting a range expansion around this time. More recent, secondary increases in Ne were inferred for the Misool and North Great Barrier Reef sampling locations, but joint modelling did not clarify whether these were due to population growth, migration, or both. Despite the greater genetic diversity and ancient Ne observed at sites around Australia and the Coral Triangle, remote reefs around north-western New Caledonia had the highest contemporary Ne, demonstrating the importance of using multiple population size assessment methods. This study provides insight into both the past and present demographics of C. amblyrhynchos and contributes to our understanding of evolution in marine biodiversity hotspots.
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40
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Searching for genetic evidence of demographic decline in an arctic seabird: beware of overlapping generations. Heredity (Edinb) 2022; 128:364-376. [PMID: 35246618 PMCID: PMC9076905 DOI: 10.1038/s41437-022-00515-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 02/12/2022] [Accepted: 02/14/2022] [Indexed: 11/09/2022] Open
Abstract
Genetic data are useful for detecting sudden population declines in species that are difficult to study in the field. Yet this indirect approach has its own drawbacks, including population structure, mutation patterns, and generation overlap. The ivory gull (Pagophila eburnea), a long-lived Arctic seabird, is currently suffering from rapid alteration of its primary habitat (i.e., sea ice), and dramatic climatic events affecting reproduction and recruitment. However, ivory gulls live in remote areas, and it is difficult to assess the population trend of the species across its distribution. Here we present complementary microsatellite- and SNP-based genetic analyses to test a recent bottleneck genetic signal in ivory gulls over a large portion of their distribution. With attention to the potential effects of population structure, mutation patterns, and sample size, we found no significant signatures of population decline worldwide. At a finer scale, we found a significant bottleneck signal at one location in Canada. These results were compared with predictions from simulations showing how generation time and generation overlap can delay and reduce the bottleneck microsatellite heterozygosity excess signal. The consistency of the results obtained with independent methods strongly indicates that the species shows no genetic evidence of an overall decline in population size. However, drawing conclusions related to the species' population trends will require a better understanding of the effect of age structure in long-lived species. In addition, estimates of the effective global population size of ivory gulls were surprisingly low (~1000 ind.), suggesting that the evolutionary potential of the species is not assured.
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41
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Weise EM, Scribner KT, Adams JV, Boeberitz O, Jubar A, Bravener G, Johnson NS, Robinson JD. Pedigree analysis and estimates of effective breeding size characterize sea lamprey reproductive biology. Evol Appl 2022; 15:484-500. [PMID: 35386399 PMCID: PMC8965388 DOI: 10.1111/eva.13364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/19/2022] [Accepted: 02/21/2022] [Indexed: 12/02/2022] Open
Abstract
The sea lamprey (Petromyzon marinus) is an invasive species in the Great Lakes and the focus of a large control and assessment program. Current assessment methods provide information on the census size of spawning adult sea lamprey in a small number of streams, but information characterizing reproductive success of spawning adults is rarely available. We used RAD-capture sequencing to genotype single nucleotide polymorphism (SNP) loci for ~1600 sea lamprey larvae collected from three streams in northern Michigan (Black Mallard, Pigeon, and Ocqueoc Rivers). Larval genotypes were used to reconstruct family pedigrees, which were combined with Gaussian mixture analyses to identify larval age classes for estimation of spawning population size. Two complementary estimates of effective breeding size (N b), as well as the extrapolated minimum number of spawners (N s), were also generated for each cohort. Reconstructed pedigrees highlighted inaccuracies of cohort assignments from traditionally used mixture analyses. However, combining genotype-based pedigree information with length-at-age assignment of cohort membership greatly improved cohort identification accuracy. Population estimates across all three streams sampled in this study indicate a small number of successfully spawning adults when barriers were in operation, implying that barriers limited adult spawning numbers but were not completely effective at blocking access to spawning habitats. Thus, the large numbers of larvae present in sampled systems were a poor indicator of spawning adult abundance. Overall, pedigree-based N b and N s estimates provide a promising and rapid assessment tool for sea lamprey and other species.
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Affiliation(s)
- Ellen M. Weise
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
| | - Kim T. Scribner
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
- Department of Integrative BiologyMichigan State UniversityEast LansingMichiganUSA
| | - Jean V. Adams
- US Geological Survey ‐ Great Lakes Science CenterAnn ArborMichiganUSA
| | - Olivia Boeberitz
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
| | | | - Gale Bravener
- Fisheries and Oceans CanadaSea Lamprey Control CentreSault Ste. MarieOntarioCanada
| | - Nicholas S. Johnson
- US Geological SurveyGreat Lakes Science CenterHammond Bay Biological StationMillersburgMichiganUSA
| | - John D. Robinson
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMichiganUSA
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42
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Hornick KM, Plough LV. Genome-wide analysis of natural and restored eastern oyster populations reveals local adaptation and positive impacts of planting frequency and broodstock number. Evol Appl 2022; 15:40-59. [PMID: 35126647 PMCID: PMC8792482 DOI: 10.1111/eva.13322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 10/22/2021] [Accepted: 10/24/2021] [Indexed: 01/20/2023] Open
Abstract
The release of captive-bred plants and animals has increased worldwide to augment declining species. However, insufficient attention has been given to understanding how neutral and adaptive genetic variation are partitioned within and among proximal natural populations, and the patterns and drivers of gene flow over small spatial scales, which can be important for restoration success. A seascape genomics approach was used to investigate population structure, local adaptation, and the extent to which environmental gradients influence genetic variation among natural and restored populations of Chesapeake Bay eastern oysters Crassostrea virginica. We also investigated the impact of hatchery practices on neutral genetic diversity of restored reefs and quantified the broader genetic impacts of large-scale hatchery-based bivalve restoration. Restored reefs showed similar levels of diversity as natural reefs, and striking relationships were found between planting frequency and broodstock numbers and genetic diversity metrics (effective population size and relatedness), suggesting that hatchery practices can have a major impact on diversity. Despite long-term restoration activities, haphazard historical translocations, and high dispersal potential of larvae that could homogenize allele frequencies among populations, moderate neutral population genetic structure was uncovered. Moreover, environmental factors, namely salinity, pH, and temperature, play a major role in the distribution of neutral and adaptive genetic variation. For marine invertebrates in heterogeneous seascapes, collecting broodstock from large populations experiencing similar environments to candidate sites may provide the most appropriate sources for restoration and ensure population resilience in the face of rapid environmental change. This is one of a few studies to demonstrate empirically that hatchery practices have a major impact on the retention of genetic diversity. Overall, these results contribute to the growing body of evidence for fine-scale genetic structure and local adaptation in broadcast-spawning marine species and provide novel information for the management of an important fisheries resource.
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Affiliation(s)
- Katherine M. Hornick
- University of Maryland Center for Environmental ScienceHorn Point LaboratoryCambridgeMarylandUSA
| | - Louis V. Plough
- University of Maryland Center for Environmental ScienceHorn Point LaboratoryCambridgeMarylandUSA
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43
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Huang K, Dunn DW, Li W, Wang D, Li B. Linkage disequilibrium under polysomic inheritance. Heredity (Edinb) 2022; 128:11-20. [PMID: 34983965 PMCID: PMC8733019 DOI: 10.1038/s41437-021-00482-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 10/13/2021] [Accepted: 10/18/2021] [Indexed: 01/03/2023] Open
Abstract
Linkage disequilibrium (LD) is the non-random association of alleles at different loci. Squared LD coefficients r2 (for phased genotypes) and [Formula: see text] (for unphased genotypes) will converge to constants that are determined by the sample size, the recombination frequency, the effective population size and the mating system. LD can therefore be used for gene mapping and the estimation of effective population size. However, current methods work only with diploids. To resolve this problem, we here extend the linkage disequilibrium measures to include polysomic inheritance. We derive the values of r2 and [Formula: see text] at equilibrium state for various mating systems and different ploidy levels. For unlinked loci, [Formula: see text] for monoecious and dioecious (with random pairing) mating systems or [Formula: see text] for dioecious mating systems (with lifetime pairing), where f is the number of females in a half-sib family and η is a constant related to the ploidy level. We simulate the application of estimating Ne using unphased genotypes. We find that estimating Ne in polyploids requires similar sample sizes and numbers of loci as in diploids, with the main source of bias due to using 0.5 as the recombination frequency.
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Affiliation(s)
- Kang Huang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, 710069, China
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, V6T1Z4, Canada
| | - Derek W Dunn
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Wenkai Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Dan Wang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, 710069, China.
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, 650223, China.
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44
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Ackiss AS, Magee MR, Sass GG, Turnquist K, McIntyre PB, Larson WA. Genomic and environmental influences on resilience in a cold-water fish near the edge of its range. Evol Appl 2021; 14:2794-2814. [PMID: 34950230 PMCID: PMC8674893 DOI: 10.1111/eva.13313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 10/05/2021] [Accepted: 10/07/2021] [Indexed: 02/06/2023] Open
Abstract
Small, isolated populations present a challenge for conservation. The dueling effects of selection and drift in a limited pool of genetic diversity make the responses of small populations to environmental perturbations erratic and difficult to predict. This is particularly true at the edge of a species range, where populations often persist at the limits of their environmental tolerances. Populations of cisco, Coregonus artedi, in inland lakes have experienced numerous extirpations along the southern edge of their range in recent decades, which are thought to result from environmental degradation and loss of cold, well-oxygenated habitat as lakes warm. Yet, cisco extirpations do not show a clear latitudinal pattern, suggesting that local environmental factors and potentially local adaptation may influence resilience. Here, we used genomic tools to investigate the nature of this pattern of resilience. We used restriction site-associated DNA capture (Rapture) sequencing to survey genomic diversity and differentiation in southern inland lake cisco populations and compared the frequency of deleterious mutations that potentially influence fitness across lakes. We also examined haplotype diversity in a region of the major histocompatibility complex involved in stress and immune system response. We correlated these metrics to spatial and environmental factors including latitude, lake size, and measures of oxythermal habitat and found significant relationships between genetic metrics and broad and local factors. High levels of genetic differentiation among populations were punctuated by a phylogeographic break and residual patterns of isolation-by-distance. Although the prevalence of deleterious mutations and inbreeding coefficients was significantly correlated with latitude, neutral and non-neutral genetic diversity were most strongly correlated with lake surface area. Notably, differences among lakes in the availability of estimated oxythermal habitat left no clear population genomic signature. Our results shed light on the complex dynamics influencing these isolated populations and provide valuable information for their conservation.
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Affiliation(s)
- Amanda S. Ackiss
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
- U.S. Geological SurveyGreat Lakes Science CenterAnn ArborMichiganUSA
| | | | - Greg G. Sass
- Escanaba Lake Research StationWisconsin Department of Natural ResourcesBoulder JunctionWisconsinUSA
| | - Keith Turnquist
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
| | - Peter B. McIntyre
- Department of Natural Resources and the EnvironmentCornell UniversityIthacaNew YorkUSA
| | - Wesley A. Larson
- U.S. Geological SurveyWisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
- National Oceanographic and Atmospheric AdministrationNational Marine Fisheries ServiceAlaska Fisheries Science CenterAuke Bay LaboratoriesJuneauAlaskaUSA
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45
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Šnjegota D, Stronen AV, Boljte B, Ćirović D, Djan M, Huber D, Jelenčič M, Konec M, Kusak J, Skrbinšek T. Population genetic structure of wolves in the northwestern Dinaric-Balkan region. Ecol Evol 2021; 11:18492-18504. [PMID: 35003687 PMCID: PMC8717286 DOI: 10.1002/ece3.8444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 11/25/2021] [Accepted: 11/26/2021] [Indexed: 11/29/2022] Open
Abstract
The Balkan Peninsula and the Dinaric Mountains possess extraordinary biodiversity and support one of the largest and most diverse wolf (Canis lupus) populations in Europe. Results obtained with diverse genetic markers show west-east substructure, also seen in various other species, despite the absence of obvious barriers to movement. However, the spatial extent of the genetic clusters remains unresolved, and our aim was to combine fine-scale sampling with population and spatial genetic analyses to improve resolution of wolf genetic clusters. We analyzed 16 autosomal microsatellites from 255 wolves sampled in Slovenia, Croatia, Bosnia and Herzegovina (BIH), and Serbia and documented three genetic clusters. These comprised (1) Slovenia and the regions of Gorski kotar and Lika in Croatia, (2) the region of Dalmatia in southern Croatia and BIH, and (3) Serbia. When we mapped the clusters geographically, we observed west-east genetic structure across the study area, together with some specific structure in BIH-Dalmatia. We observed that cluster 1 had a smaller effective population size, consistent with earlier reports of population recovery since the 1980s. Our results provide foundation for future genomic studies that would further resolve the observed west-east population structure and its evolutionary history in wolves and other taxa in the region and identify focal areas for habitat conservation. They also have immediate importance for conservation planning for the wolves in one of the most important parts of the species' European range.
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Affiliation(s)
- Dragana Šnjegota
- Department of Biology and EcologyFaculty of Natural Sciences and MathematicsUniversity of Banja LukaBanja LukaBosnia and Herzegovina
| | - Astrid Vik Stronen
- Department of BiologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Barbara Boljte
- Department of BiologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Duško Ćirović
- Faculty of BiologyUniversity of BelgradeBelgradeSerbia
| | - Mihajla Djan
- Department of Biology and EcologyFaculty of SciencesUniversity of Novi SadNovi SadSerbia
| | - Djuro Huber
- Department of BiologyFaculty of Veterinary MedicineUniversity of ZagrebZagrebCroatia
| | - Maja Jelenčič
- Department of BiologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Marjeta Konec
- Department of BiologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Josip Kusak
- Department of BiologyFaculty of Veterinary MedicineUniversity of ZagrebZagrebCroatia
| | - Tomaž Skrbinšek
- Department of BiologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
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46
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Saura M, Caballero A, Santiago E, Fernández A, Morales-González E, Fernández J, Cabaleiro S, Millán A, Martínez P, Palaiokostas C, Kocour M, Aslam ML, Houston RD, Prchal M, Bargelloni L, Tzokas K, Haffray P, Bruant JS, Villanueva B. Estimates of recent and historical effective population size in turbot, seabream, seabass and carp selective breeding programmes. Genet Sel Evol 2021; 53:85. [PMID: 34742227 PMCID: PMC8572424 DOI: 10.1186/s12711-021-00680-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 10/22/2021] [Indexed: 11/15/2022] Open
Abstract
Background The high fecundity of fish species allows intense selection to be practised and therefore leads to fast genetic gains. Based on this, numerous selective breeding programmes have been started in Europe in the last decades, but in general, little is known about how the base populations of breeders have been built. Such knowledge is important because base populations can be created from very few individuals, which can lead to small effective population sizes and associated reductions in genetic variability. In this study, we used genomic information that was recently made available for turbot (Scophthalmus maximus), gilthead seabream (Sparus aurata), European seabass (Dicentrarchus labrax) and common carp (Cyprinus carpio) to obtain accurate estimates of the effective size for commercial populations. Methods Restriction-site associated DNA sequencing data were used to estimate current and historical effective population sizes. We used a novel method that considers the linkage disequilibrium spectrum for the whole range of genetic distances between all pairs of single nucleotide polymorphisms (SNPs), and thus accounts for potential fluctuations in population size over time. Results Our results show that the current effective population size for these populations is small (equal to or less than 50 fish), potentially putting the sustainability of the breeding programmes at risk. We have also detected important drops in effective population size about five to nine generations ago, most likely as a result of domestication and the start of selective breeding programmes for these species in Europe. Conclusions Our findings highlight the need to broaden the genetic composition of the base populations from which selection programmes start, and suggest that measures designed to increase effective population size within all farmed populations analysed here should be implemented in order to manage genetic variability and ensure the sustainability of the breeding programmes. Supplementary Information The online version contains supplementary material available at 10.1186/s12711-021-00680-9.
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Affiliation(s)
- María Saura
- Departamento de Mejora Genética Animal, INIA-CSIC, Ctra. de La Coruña, km 7.5, 28040, Madrid, Spain.
| | - Armando Caballero
- Centro de Investigación Mariña, Facultade de Bioloxía, Universidade de Vigo, 36310, Vigo, Spain
| | - Enrique Santiago
- Departamento de Biología Funcional, Universidad de Oviedo, C/ Julián Clavería s/n, 33006, Oviedo, Spain
| | - Almudena Fernández
- Departamento de Mejora Genética Animal, INIA-CSIC, Ctra. de La Coruña, km 7.5, 28040, Madrid, Spain
| | | | - Jesús Fernández
- Departamento de Mejora Genética Animal, INIA-CSIC, Ctra. de La Coruña, km 7.5, 28040, Madrid, Spain
| | - Santiago Cabaleiro
- CETGA, Cluster de Acuicultura de Galicia, Punta do Couso s/n, 15695, Aguiño-Ribeira, Spain
| | | | - Paulino Martínez
- Departament of Zoology, Genetics and Physical Anthropology, Universidade de Santiago de Compostela, 27002, Lugo, Spain
| | - Christos Palaiokostas
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Martin Kocour
- South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in České Budějovice, Zátiší 728/II, 389 25, Vodňany, Czech Republic
| | | | - Ross D Houston
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Martin Prchal
- South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in České Budějovice, Zátiší 728/II, 389 25, Vodňany, Czech Republic
| | - Luca Bargelloni
- Universitá degli Studi di Padova, Via 8 Febbraio 1848, 2, 35122, Padova, PD, Italy
| | - Kostas Tzokas
- Andromeda Group SA, Leof. Lavriou 99, 190 02, Peania, Greece
| | - Pierrick Haffray
- SYSAAF, Station LPGP/INRAE, Campus de Beaulieu, 35042, Rennes, France
| | | | - Beatriz Villanueva
- Departamento de Mejora Genética Animal, INIA-CSIC, Ctra. de La Coruña, km 7.5, 28040, Madrid, Spain
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47
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Murphy SM, Adams JR, Waits LP, Cox JJ. Evaluating otter reintroduction outcomes using genetic spatial capture-recapture modified for dendritic networks. Ecol Evol 2021; 11:15047-15061. [PMID: 34765159 PMCID: PMC8571598 DOI: 10.1002/ece3.8187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/06/2021] [Accepted: 09/10/2021] [Indexed: 11/23/2022] Open
Abstract
Monitoring the demographics and genetics of reintroduced populations is critical to evaluating reintroduction success, but species ecology and the landscapes that they inhabit often present challenges for accurate assessments. If suitable habitats are restricted to hierarchical dendritic networks, such as river systems, animal movements are typically constrained and may violate assumptions of methods commonly used to estimate demographic parameters. Using genetic detection data collected via fecal sampling at latrines, we demonstrate applicability of the spatial capture-recapture (SCR) network distance function for estimating the size and density of a recently reintroduced North American river otter (Lontra canadensis) population in the Upper Rio Grande River dendritic network in the southwestern United States, and we also evaluated the genetic outcomes of using a small founder group (n = 33 otters) for reintroduction. Estimated population density was 0.23-0.28 otter/km, or 1 otter/3.57-4.35 km, with weak evidence of density increasing with northerly latitude (β = 0.33). Estimated population size was 83-104 total otters in 359 km of riverine dendritic network, which corresponded to average annual exponential population growth of 1.12-1.15/year since reintroduction. Growth was ≥40% lower than most reintroduced river otter populations and strong evidence of a founder effect existed 8-10 years post-reintroduction, including 13-21% genetic diversity loss, 84%-87% genetic effective population size decline, and rapid divergence from the source population (F ST accumulation = 0.06/generation). Consequently, genetic restoration via translocation of additional otters from other populations may be necessary to mitigate deleterious genetic effects in this small, isolated population. Combined with non-invasive genetic sampling, the SCR network distance approach is likely widely applicable to demogenetic assessments of both reintroduced and established populations of multiple mustelid species that inhabit aquatic dendritic networks, many of which are regionally or globally imperiled and may warrant reintroduction or augmentation efforts.
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Affiliation(s)
- Sean M. Murphy
- Wildlife Management DivisionNew Mexico Department of Game & FishSanta FeNew MexicoUSA
| | - Jennifer R. Adams
- Department of Fish and Wildlife SciencesUniversity of IdahoMoscowIdahoUSA
| | - Lisette P. Waits
- Department of Fish and Wildlife SciencesUniversity of IdahoMoscowIdahoUSA
| | - John J. Cox
- Department of Forestry and Natural ResourcesUniversity of KentuckyLexingtonKentuckyUSA
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48
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Waples RS. Relative Precision of the Sibship and LD Methods for Estimating Effective Population Size With Genomics-Scale Datasets. J Hered 2021; 112:535-539. [PMID: 34283240 DOI: 10.1093/jhered/esab042] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 07/19/2021] [Indexed: 11/12/2022] Open
Abstract
Computer simulations were used to compare relative precision of 2 widely used single-sample methods for estimating effective population size (Ne)-the sibship method and the linkage disequilibrium (LD) method. Emphasis is on performance when thousands of gene loci are used, which now can easily be achieved even for nonmodel species. Results show that unless Ne is very small, if at least 500-2000 diallelic loci are used, precision of the LD method is higher than the maximum possible precision for the sibship method, which occurs when all sibling relationships have been correctly identified. Results also show that when precision is high for both methods, their estimates of Ne are highly and positively correlated, which limits additional gains in precision that might be obtained by combining information from the 2 estimators.
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Affiliation(s)
- Robin S Waples
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA 98112, USA (Waples)
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49
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Nadachowska‐Brzyska K, Konczal M, Babik W. Navigating the temporal continuum of effective population size. Methods Ecol Evol 2021. [DOI: 10.1111/2041-210x.13740] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | | | - Wieslaw Babik
- Jagiellonian University in Kraków Faculty of Biology Institute of Environmental Sciences Kraków Poland
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50
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Bilgmann K, Armansin N, Ferchaud A, Normandeau E, Bernatchez L, Harcourt R, Ahonen H, Lowther A, Goldsworthy S, Stow A. Low effective population size in the genetically bottlenecked Australian sea lion is insufficient to maintain genetic variation. Anim Conserv 2021. [DOI: 10.1111/acv.12688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K. Bilgmann
- Department of Biological Sciences Macquarie University Sydney Australia
| | - N. Armansin
- Department of Biological Sciences Macquarie University Sydney Australia
| | - A.L. Ferchaud
- Département de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec QC Canada
| | - E. Normandeau
- Département de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec QC Canada
| | - L. Bernatchez
- Département de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec QC Canada
| | - R. Harcourt
- Department of Biological Sciences Macquarie University Sydney Australia
| | - H. Ahonen
- Department of Biological Sciences Macquarie University Sydney Australia
- Norwegian Polar Institute Tromsø Norway
| | | | - S.D. Goldsworthy
- South Australian Research and Development Institute Adelaide South Australia
| | - A. Stow
- Department of Biological Sciences Macquarie University Sydney Australia
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