1
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Dickel L, Arcese P, Keller LF, Nietlisbach P, Goedert D, Jensen H, Reid JM. Multigenerational Fitness Effects of Natural Immigration Indicate Strong Heterosis and Epistatic Breakdown in a Wild Bird Population. Am Nat 2024; 203:411-431. [PMID: 38358807 DOI: 10.1086/728669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
AbstractThe fitness of immigrants and their descendants produced within recipient populations fundamentally underpins the genetic and population dynamic consequences of immigration. Immigrants can in principle induce contrasting genetic effects on fitness across generations, reflecting multifaceted additive, dominance, and epistatic effects. Yet full multigenerational and sex-specific fitness effects of regular immigration have not been quantified within naturally structured systems, precluding inference on underlying genetic architectures and population outcomes. We used four decades of song sparrow (Melospiza melodia) life history and pedigree data to quantify fitness of natural immigrants, natives, and their F1, F2, and backcross descendants and test for evidence of nonadditive genetic effects. Values of key fitness components (including adult lifetime reproductive success and zygote survival) of F1 offspring of immigrant-native matings substantially exceeded their parent mean, indicating strong heterosis. Meanwhile, F2 offspring of F1-F1 matings had notably low values, indicating surprisingly strong epistatic breakdown. Furthermore, magnitudes of effects varied among fitness components and differed between female and male descendants. These results demonstrate that strong nonadditive genetic effects on fitness can arise within weakly structured and fragmented populations experiencing frequent natural immigration. Such effects will substantially affect the net degree of effective gene flow and resulting local genetic introgression and adaptation.
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2
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Reid JM, Dickel L, Keller LF, Nietlisbach P, Arcese P. Multi-generation genetic contributions of immigrants reveal cryptic elevated and sex-biased effective gene flow within a natural meta-population. Ecol Lett 2024; 27:e14377. [PMID: 38361472 DOI: 10.1111/ele.14377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 01/11/2024] [Accepted: 01/11/2024] [Indexed: 02/17/2024]
Abstract
Impacts of immigration on micro-evolution and population dynamics fundamentally depend on net rates and forms of resulting gene flow into recipient populations. Yet, the degrees to which observed rates and sex ratios of physical immigration translate into multi-generational genetic legacies have not been explicitly quantified in natural meta-populations, precluding inference on how movements translate into effective gene flow and eco-evolutionary outcomes. Our analyses of three decades of complete song sparrow (Melospiza melodia) pedigree data show that multi-generational genetic contributions from regular natural immigrants substantially exceeded those from contemporary natives, consistent with heterosis-enhanced introgression. However, while contributions from female immigrants exceeded those from female natives by up to three-fold, male immigrants' lineages typically went locally extinct soon after arriving. Both the overall magnitude, and the degree of female bias, of effective gene flow therefore greatly exceeded those which would be inferred from observed physical arrivals, altering multiple eco-evolutionary implications of immigration.
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Affiliation(s)
- Jane M Reid
- Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Lisa Dickel
- Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Lukas F Keller
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Natural History Museum, University of Zurich, Zurich, Switzerland
| | - Pirmin Nietlisbach
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Peter Arcese
- Department of Forest & Conservation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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3
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Grummer JA, Booker TR, Matthey-Doret R, Nietlisbach P, Thomaz AT, Whitlock MC. The immediate costs and long-term benefits of assisted gene flow in large populations. Conserv Biol 2022; 36:e13911. [PMID: 35390208 DOI: 10.1111/cobi.13911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 12/11/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
With the genetic health of many plant and animal populations deteriorating due to climate change outpacing adaptation, interventions, such as assisted gene flow (AGF), may provide genetic variation necessary for populations to adapt to climate change. We ran genetic simulations to mimic different AGF scenarios in large populations and measured their outcomes on population-level fitness to determine circumstances in which it is worthwhile to perform AGF. In the absence of inbreeding depression, AGF was beneficial within a few generations only when introduced genotypes had much higher fitness than local individuals and traits affecting fitness were controlled by a few genes of large effect. AGF was harmful over short periods (e.g., first ∼10-20 generations) if there was strong outbreeding depression or introduced deleterious genetic variation. When the adaptive trait was controlled by many loci of small effect, the benefits of AGF took over 10 generations to realize-potentially too long for most climate-related management scenarios. The genomic integrity of the recipient population typically remained intact following AGF; the amount of genetic material from the donor population usually constituted no more of the recipient population's genome than the fraction of the population introduced. Significant genomic turnover (e.g., >50% replacement) only occurred when the selective advantage of the adaptive trait and translocation fraction were extremely high. Our results will be useful when adaptive management is used to maintain the genetic health and productivity of large populations under climate change.
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Affiliation(s)
- Jared A Grummer
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tom R Booker
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Remi Matthey-Doret
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Pirmin Nietlisbach
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Andréa T Thomaz
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Michael C Whitlock
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
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4
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Bonnet T, Morrissey MB, de Villemereuil P, Alberts SC, Arcese P, Bailey LD, Boutin S, Brekke P, Brent LJN, Camenisch G, Charmantier A, Clutton-Brock TH, Cockburn A, Coltman DW, Courtiol A, Davidian E, Evans SR, Ewen JG, Festa-Bianchet M, de Franceschi C, Gustafsson L, Höner OP, Houslay TM, Keller LF, Manser M, McAdam AG, McLean E, Nietlisbach P, Osmond HL, Pemberton JM, Postma E, Reid JM, Rutschmann A, Santure AW, Sheldon BC, Slate J, Teplitsky C, Visser ME, Wachter B, Kruuk LEB. Genetic variance in fitness indicates rapid contemporary adaptive evolution in wild animals. Science 2022; 376:1012-1016. [PMID: 35617403 DOI: 10.1126/science.abk0853] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The rate of adaptive evolution, the contribution of selection to genetic changes that increase mean fitness, is determined by the additive genetic variance in individual relative fitness. To date, there are few robust estimates of this parameter for natural populations, and it is therefore unclear whether adaptive evolution can play a meaningful role in short-term population dynamics. We developed and applied quantitative genetic methods to long-term datasets from 19 wild bird and mammal populations and found that, while estimates vary between populations, additive genetic variance in relative fitness is often substantial and, on average, twice that of previous estimates. We show that these rates of contemporary adaptive evolution can affect population dynamics and hence that natural selection has the potential to partly mitigate effects of current environmental change.
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Affiliation(s)
- Timothée Bonnet
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | | | - Pierre de Villemereuil
- Institut de Systématique, Évolution, Biodiversité (ISYEB), École Pratique des Hautes Études, PSL, MNHN, CNRS, SU, UA, Paris, France.,School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Susan C Alberts
- Departments of Biology and Evolutionary Anthropology, Duke University, Durham, NC, USA
| | - Peter Arcese
- Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Liam D Bailey
- Departments of Evolutionary Ecology and Evolutionary Genetics, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Stan Boutin
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Patricia Brekke
- Institute of Zoology, Zoological Society of London, Regents Park, London, UK
| | - Lauren J N Brent
- Centre for Research in Animal Behaviour, University of Exeter, Penryn, UK
| | - Glauco Camenisch
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Anne Charmantier
- Centre d'Écologie Fonctionnelle et Évolutive, Université de Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Tim H Clutton-Brock
- Department of Zoology, University of Cambridge, Cambridge, UK.,Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Andrew Cockburn
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - David W Coltman
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Alexandre Courtiol
- Departments of Evolutionary Ecology and Evolutionary Genetics, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Eve Davidian
- Departments of Evolutionary Ecology and Evolutionary Genetics, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Simon R Evans
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK.,Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden.,Centre for Ecology and Conservation, University of Exeter, Penryn, UK
| | - John G Ewen
- Institute of Zoology, Zoological Society of London, Regents Park, London, UK
| | | | - Christophe de Franceschi
- Centre d'Écologie Fonctionnelle et Évolutive, Université de Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Lars Gustafsson
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Oliver P Höner
- Departments of Evolutionary Ecology and Evolutionary Genetics, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Thomas M Houslay
- Department of Zoology, University of Cambridge, Cambridge, UK.,Centre for Ecology and Conservation, University of Exeter, Penryn, UK
| | - Lukas F Keller
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.,Zoological Museum, University of Zurich,, Zurich, Switzerland
| | - Marta Manser
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.,Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Andrew G McAdam
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA
| | - Emily McLean
- Biology Department, Oxford College, Emory University, Oxford, GA, USA
| | - Pirmin Nietlisbach
- School of Biological Sciences, Illinois State University, Normal, IL, USA
| | - Helen L Osmond
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | | | - Erik Postma
- Centre for Ecology and Conservation, University of Exeter, Penryn, UK
| | - Jane M Reid
- Centre for Biodiversity Dynamics, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.,School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Alexis Rutschmann
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Anna W Santure
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Ben C Sheldon
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK
| | - Jon Slate
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Sheffield, UK
| | - Céline Teplitsky
- Centre d'Écologie Fonctionnelle et Évolutive, Université de Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Marcel E Visser
- Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, Netherlands
| | - Bettina Wachter
- Departments of Evolutionary Ecology and Evolutionary Genetics, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Loeske E B Kruuk
- Research School of Biology, Australian National University, Canberra, ACT, Australia.,Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
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5
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Dickel L, Arcese P, Nietlisbach P, Keller LF, Jensen H, Reid JM. Are immigrants outbred and unrelated? Testing standard assumptions in a wild metapopulation. Mol Ecol 2021; 30:5674-5686. [PMID: 34516687 DOI: 10.1111/mec.16173] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 11/30/2022]
Abstract
Immigration into small recipient populations is expected to alleviate inbreeding and increase genetic variation, and hence facilitate population persistence through genetic and/or evolutionary rescue. Such expectations depend on three standard assumptions: that immigrants are outbred, unrelated to existing natives at arrival, and unrelated to each other. These assumptions are rarely explicitly verified, including in key field systems in evolutionary ecology. Yet, they could be violated due to non-random or repeated immigration from adjacent small populations. We combined molecular genetic marker data for 150-160 microsatellite loci with comprehensive pedigree data to test the three assumptions for a song sparrow (Melospiza melodia) population that is a model system for quantifying effects of inbreeding and immigration in the wild. Immigrants were less homozygous than existing natives on average, with mean homozygosity that closely resembled outbred natives. Immigrants can therefore be considered outbred on the focal population scale. Comparisons of homozygosity of real or hypothetical offspring of immigrant-native, native-native and immigrant-immigrant pairings implied that immigrants were typically unrelated to existing natives and to each other. Indeed, immigrants' offspring would be even less homozygous than outbred individuals on the focal population scale. The three standard assumptions of population genetic and evolutionary theory were consequently largely validated. Yet, our analyses revealed some deviations that should be accounted for in future analyses of heterosis and inbreeding depression, implying that the three assumptions should be verified in other systems to probe patterns of non-random or repeated dispersal and facilitate precise and unbiased estimation of key evolutionary parameters.
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Affiliation(s)
- Lisa Dickel
- Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Peter Arcese
- Department of Forest & Conservation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Pirmin Nietlisbach
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Lukas F Keller
- Department of Evolutionary Biology & Environmental Studies, University of Zurich, Zurich, Switzerland.,Zoological Museum, University of Zurich, Zurich, Switzerland
| | - Henrik Jensen
- Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Jane M Reid
- Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, Trondheim, Norway.,School of Biological Sciences, University of Aberdeen, Aberdeen, UK
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6
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Reid JM, Arcese P, Nietlisbach P, Wolak ME, Muff S, Dickel L, Keller LF. Immigration counter-acts local micro-evolution of a major fitness component: Migration-selection balance in free-living song sparrows. Evol Lett 2021; 5:48-60. [PMID: 33552535 PMCID: PMC7857281 DOI: 10.1002/evl3.214] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/28/2020] [Accepted: 12/18/2020] [Indexed: 01/11/2023] Open
Abstract
Ongoing adaptive evolution, and resulting “evolutionary rescue” of declining populations, requires additive genetic variation in fitness. Such variation can be increased by gene flow resulting from immigration, potentially facilitating evolution. But, gene flow could in fact constrain rather than facilitate local adaptive evolution if immigrants have low additive genetic values for local fitness. Local migration‐selection balance and micro‐evolutionary stasis could then result. However, key quantitative genetic effects of natural immigration, comprising the degrees to which gene flow increases the total local additive genetic variance yet counteracts local adaptive evolutionary change, have not been explicitly quantified in wild populations. Key implications of gene flow for population and evolutionary dynamics consequently remain unclear. Our quantitative genetic analyses of long‐term data from free‐living song sparrows (Melospiza melodia) show that mean breeding value for local juvenile survival to adulthood, a major component of fitness, increased across cohorts more than expected solely due to drift. Such micro‐evolutionary change should be expected given nonzero additive genetic variance and consistent directional selection. However, this evolutionary increase was counteracted by negative additive genetic effects of recent immigrants, which increased total additive genetic variance but prevented a net directional evolutionary increase in total additive genetic value. These analyses imply an approximate quantitative genetic migration‐selection balance in a major fitness component, and hence demonstrate a key mechanism by which substantial additive genetic variation can be maintained yet decoupled from local adaptive evolutionary change.
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Affiliation(s)
- Jane M Reid
- Centre for Biodiversity Dynamics NTNU Trondheim Norway.,School of Biological Sciences University of Aberdeen Aberdeen UK
| | - Peter Arcese
- Forest & Conservation Sciences University of British Columbia Vancouver British Columbia Canada
| | - Pirmin Nietlisbach
- School of Biological Sciences Illinois State University Normal Illinois USA
| | - Matthew E Wolak
- Department of Biological Sciences Auburn University Auburn Alaska USA
| | - Stefanie Muff
- Centre for Biodiversity Dynamics NTNU Trondheim Norway.,Department of Mathematical Sciences NTNU Trondheim Norway
| | - Lisa Dickel
- Centre for Biodiversity Dynamics NTNU Trondheim Norway
| | - Lukas F Keller
- Department of Evolutionary Biology & Environmental Studies University of Zurich Zurich Switzerland.,Zoological Museum University of Zurich Zurich Switzerland
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7
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Reid JM, Nietlisbach P, Wolak ME, Keller LF, Arcese P. Individuals' expected genetic contributions to future generations, reproductive value, and short-term metrics of fitness in free-living song sparrows ( Melospiza melodia). Evol Lett 2019; 3:271-285. [PMID: 31171983 PMCID: PMC6546383 DOI: 10.1002/evl3.118] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/01/2019] [Indexed: 11/08/2022] Open
Abstract
Appropriately defining and enumerating "fitness" is fundamental to explaining and predicting evolutionary dynamics. Yet, general theoretical concepts of fitness are often hard to translate into quantities that can be measured in wild populations experiencing complex environmental, demographic, genetic, and selective variation. Although the "fittest" entities might be widely understood to be those that ultimately leave most descendants at some future time, such long-term legacies can rarely be measured, impeding evaluation of the degree to which tractable short-term metrics of individual fitness could potentially serve as useful direct proxies. One opportunity for conceptual and empirical convergence stems from the principle of individual reproductive value (V i), here defined as the number of copies of each of an individual's alleles that is expected to be present in future generations given the individual's realized pedigree of descendants. As V i tightly predicts an individual's longer term genetic contribution, quantifying V i provides a tractable route to quantifying what, to date, has been an abstract theoretical fitness concept. We used complete pedigree data from free-living song sparrows (Melospiza melodia) to demonstrate that individuals' expected genetic contributions stabilize within an observed 20-year (i.e. approximately eight generation) time period, allowing estimation of individual V i. Considerable among-individual variation in V i was evident in both sexes. Standard metrics of individual lifetime fitness, comprising lifespan, lifetime reproductive success, and projected growth rate, typically explained less than half the variation. We thereby elucidate the degree to which fitness metrics observed on individuals concur with measures of longer term genetic contributions and consider the degree to which analyses of pedigree structure could provide useful complementary insights into evolutionary outcomes.
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Affiliation(s)
- Jane M. Reid
- School of Biological SciencesUniversity of AberdeenAberdeenUnited Kingdom
| | - Pirmin Nietlisbach
- Department of ZoologyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Matthew E. Wolak
- Department of Biological SciencesAuburn UniversityAuburnAlabama36849
| | - Lukas F. Keller
- Department of Evolutionary Biology & Environmental StudiesUniversity of ZurichZurichSwitzerland
| | - Peter Arcese
- Forest & Conservation SciencesUniversity of British ColumbiaVancouverBritish ColumbiaCanada
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8
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Nietlisbach P, Muff S, Reid JM, Whitlock MC, Keller LF. Nonequivalent lethal equivalents: Models and inbreeding metrics for unbiased estimation of inbreeding load. Evol Appl 2019; 12:266-279. [PMID: 30697338 PMCID: PMC6346663 DOI: 10.1111/eva.12713] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Revised: 09/06/2018] [Accepted: 09/09/2018] [Indexed: 02/06/2023] Open
Abstract
Inbreeding depression, the deterioration in mean trait value in progeny of related parents, is a fundamental quantity in genetics, evolutionary biology, animal and plant breeding, and conservation biology. The magnitude of inbreeding depression can be quantified by the inbreeding load, typically measured in numbers of lethal equivalents, a population genetic quantity that allows for comparisons between environments, populations or species. However, there is as yet no quantitative assessment of which combinations of statistical models and metrics of inbreeding can yield such estimates. Here, we review statistical models that have been used to estimate inbreeding load and use population genetic simulations to investigate how unbiased estimates can be obtained using genomic and pedigree-based metrics of inbreeding. We use simulated binary viability data (i.e., dead versus alive) as our example, but the concepts apply to any trait that exhibits inbreeding depression. We show that the increasingly popular generalized linear models with logit link do not provide comparable and unbiased population genetic measures of inbreeding load, independent of the metric of inbreeding used. Runs of homozygosity result in unbiased estimates of inbreeding load, whereas inbreeding measured from pedigrees results in slight overestimates. Due to widespread use of models that do not yield unbiased measures of the inbreeding load, some estimates in the literature cannot be compared meaningfully. We surveyed the literature for reliable estimates of the mean inbreeding load from wild vertebrate populations and found an average of 3.5 haploid lethal equivalents for survival to sexual maturity. To obtain comparable estimates, we encourage researchers to use generalized linear models with logarithmic links or maximum-likelihood estimation of the exponential equation, and inbreeding coefficients calculated from runs of homozygosity, provided an assembled reference genome of sufficient quality and enough genetic marker data are available.
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Affiliation(s)
- Pirmin Nietlisbach
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurichSwitzerland
- Department of ZoologyUniversity of British ColumbiaVancouverBCCanada
| | - Stefanie Muff
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurichSwitzerland
| | - Jane M. Reid
- School of Biological SciencesUniversity of AberdeenAberdeenUK
| | | | - Lukas F. Keller
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurichSwitzerland
- Zoological MuseumUniversity of ZurichZurichSwitzerland
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9
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Wolak ME, Arcese P, Keller LF, Nietlisbach P, Reid JM. Sex‐specific additive genetic variances and correlations for fitness in a song sparrow (
Melospiza melodia
) population subject to natural immigration and inbreeding. Evolution 2018; 72:2057-2075. [DOI: 10.1111/evo.13575] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 07/23/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Matthew E. Wolak
- School of Biological SciencesUniversity of Aberdeen Aberdeen Scotland
- Department of Biological SciencesAuburn University Auburn Alabama 36849
| | - Peter Arcese
- Department of Forest and Conservation SciencesUniversity of British Columbia Vancouver British Columbia Canada
| | - Lukas F. Keller
- Department of Evolutionary Biology and Environmental StudiesUniversity of Zurich Winterthurerstrasse 190 CH‐8057 Zurich Switzerland
- Zoological MuseumUniversity of Zurich Karl‐Schmid‐Strasse 4 CH‐8006 Zurich Switzerland
| | - Pirmin Nietlisbach
- Department of Evolutionary Biology and Environmental StudiesUniversity of Zurich Winterthurerstrasse 190 CH‐8057 Zurich Switzerland
- Department of ZoologyUniversity of British Columbia Vancouver British Columbia Canada
| | - Jane M. Reid
- School of Biological SciencesUniversity of Aberdeen Aberdeen Scotland
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10
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Losdat S, Germain RR, Nietlisbach P, Arcese P, Reid JM. No evidence of inbreeding depression in sperm performance traits in wild song sparrows. Ecol Evol 2018; 8:1842-1852. [PMID: 29435258 PMCID: PMC5792576 DOI: 10.1002/ece3.3721] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 09/28/2017] [Accepted: 11/20/2017] [Indexed: 11/14/2022] Open
Abstract
Inbreeding is widely hypothesized to shape mating systems and population persistence, but such effects will depend on which traits show inbreeding depression. Population and evolutionary consequences could be substantial if inbreeding decreases sperm performance and hence decreases male fertilization success and female fertility. However, the magnitude of inbreeding depression in sperm performance traits has rarely been estimated in wild populations experiencing natural variation in inbreeding. Further, the hypothesis that inbreeding could increase within-ejaculate variation in sperm traits and thereby further affect male fertilization success has not been explicitly tested. We used a wild pedigreed song sparrow (Melospiza melodia) population, where frequent extrapair copulations likely create strong postcopulatory competition for fertilization success, to quantify effects of male coefficient of inbreeding (f) on key sperm performance traits. We found no evidence of inbreeding depression in sperm motility, longevity, or velocity, and the within-ejaculate variance in sperm velocity did not increase with male f. Contrary to inferences from highly inbred captive and experimental populations, our results imply that moderate inbreeding will not necessarily constrain sperm performance in wild populations. Consequently, the widely observed individual-level and population-level inbreeding depression in male and female fitness may not stem from reduced sperm performance in inbred males.
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Affiliation(s)
- Sylvain Losdat
- Institute of Biological and Environmental SciencesSchool of Biological SciencesUniversity of AberdeenAberdeenScotland
- Institute of BiologyUniversity of NeuchâtelNeuchâtelSwitzerland
| | - Ryan R. Germain
- Institute of Biological and Environmental SciencesSchool of Biological SciencesUniversity of AberdeenAberdeenScotland
| | - Pirmin Nietlisbach
- Institute of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurichSwitzerland
- Department of ZoologyUniversity of British ColumbiaVancouverBCCanada
| | - Peter Arcese
- Department of Forest and Conservation SciencesUniversity of British ColumbiaVancouverBCCanada
| | - Jane M. Reid
- Institute of Biological and Environmental SciencesSchool of Biological SciencesUniversity of AberdeenAberdeenScotland
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11
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Nietlisbach P, Keller LF, Camenisch G, Guillaume F, Arcese P, Reid JM, Postma E. Pedigree-based inbreeding coefficient explains more variation in fitness than heterozygosity at 160 microsatellites in a wild bird population. Proc Biol Sci 2018; 284:rspb.2016.2763. [PMID: 28250184 DOI: 10.1098/rspb.2016.2763] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 02/06/2017] [Indexed: 01/14/2023] Open
Abstract
Although the pedigree-based inbreeding coefficient F predicts the expected proportion of an individual's genome that is identical-by-descent (IBD), heterozygosity at genetic markers captures Mendelian sampling variation and thereby provides an estimate of realized IBD. Realized IBD should hence explain more variation in fitness than their pedigree-based expectations, but how many markers are required to achieve this in practice remains poorly understood. We use extensive pedigree and life-history data from an island population of song sparrows (Melospiza melodia) to show that the number of genetic markers and pedigree depth affected the explanatory power of heterozygosity and F, respectively, but that heterozygosity measured at 160 microsatellites did not explain more variation in fitness than F This is in contrast with other studies that found heterozygosity based on far fewer markers to explain more variation in fitness than F Thus, the relative performance of marker- and pedigree-based estimates of IBD depends on the quality of the pedigree, the number, variability and location of the markers employed, and the species-specific recombination landscape, and expectations based on detailed and deep pedigrees remain valuable until we can routinely afford genotyping hundreds of phenotyped wild individuals of genetic non-model species for thousands of genetic markers.
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Affiliation(s)
- Pirmin Nietlisbach
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Lukas F Keller
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Glauco Camenisch
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Frédéric Guillaume
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Peter Arcese
- Department of Forest and Conservation Sciences, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia, V6T 1Z4, Canada
| | - Jane M Reid
- Institute of Biological and Environmental Sciences, School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen AB24 2TZ, UK
| | - Erik Postma
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.,Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall Campus, Penryn TR10 9EZ, UK
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Reid JM, Bocedi G, Nietlisbach P, Duthie AB, Wolak ME, Gow EA, Arcese P. Variation in parent-offspring kinship in socially monogamous systems with extra-pair reproduction and inbreeding. Evolution 2016; 70:1512-29. [PMID: 27174154 PMCID: PMC4949684 DOI: 10.1111/evo.12953] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 04/19/2016] [Accepted: 05/04/2016] [Indexed: 01/18/2023]
Abstract
Female extra‐pair reproduction in socially monogamous systems is predicted to cause cuckolded socially‐paired males to conditionally reduce paternal care, causing selection against extra‐pair reproduction and underlying polyandry. However, existing models and empirical studies have not explicitly considered that cuckolded males might be related to their socially‐paired female and/or to her extra‐pair mate, and therefore be related to extra‐pair offspring that they did not sire but could rear. Selection against paternal care, and hence against extra‐pair reproduction, might then be weakened. We derive metrics that quantify allele‐sharing between within‐pair and extra‐pair offspring and their mother and her socially‐paired male in terms of coefficients of kinship and inbreeding. We use song sparrow (Melospiza melodia) paternity and pedigree data to quantify these metrics, and thereby quantify the joint effects of extra‐pair reproduction and inbreeding on a brood's total allelic value to its socially‐paired parents. Cuckolded male song sparrows were almost always detectably related to extra‐pair offspring they reared. Consequently, although brood allelic value decreased substantially following female extra‐pair reproduction, this decrease was reduced by within‐pair and extra‐pair reproduction among relatives. Such complex variation in kinship within nuclear families should be incorporated into models considering coevolutionary dynamics of extra‐pair reproduction, parental care, and inbreeding.
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Affiliation(s)
- Jane M Reid
- Institute of Biological and Environmental Sciences, School of Biological Sciences, Zoology Building, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland.
| | - Greta Bocedi
- Institute of Biological and Environmental Sciences, School of Biological Sciences, Zoology Building, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland
| | - Pirmin Nietlisbach
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - A Bradley Duthie
- Institute of Biological and Environmental Sciences, School of Biological Sciences, Zoology Building, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland
| | - Matthew E Wolak
- Institute of Biological and Environmental Sciences, School of Biological Sciences, Zoology Building, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland
| | - Elizabeth A Gow
- Department of Forest and Conservation Sciences, 2424 Main Mall, University of British Columbia, Vancouver BC, Canada, V6T 1Z4
| | - Peter Arcese
- Department of Forest and Conservation Sciences, 2424 Main Mall, University of British Columbia, Vancouver BC, Canada, V6T 1Z4
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Nietlisbach P, Hadfield JD. Heritability of heterozygosity offers a new way of understanding why dominant gene action contributes to additive genetic variance. Evolution 2015; 69:1948-52. [PMID: 26100570 DOI: 10.1111/evo.12704] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 06/03/2015] [Indexed: 01/22/2023]
Abstract
Whenever allele frequencies are unequal, nonadditive gene action contributes to additive genetic variance and therefore the resemblance between parents and offspring. The reason for this has not been easy to understand. Here, we present a new single-locus decomposition of additive genetic variance that may give greater intuition about this important result. We show that the contribution of dominant gene action to parent-offspring resemblance only depends on the degree to which the heterozygosity of parents and offspring covary. Thus, dominant gene action only contributes to additive genetic variance when heterozygosity is heritable. Under most circumstances this is the case because individuals with rare alleles are more likely to be heterozygous, and because they pass rare alleles to their offspring they also tend to have heterozygous offspring. When segregating alleles are at equal frequency there are no rare alleles, the heterozygosities of parents and offspring are uncorrelated and dominant gene action does not contribute to additive genetic variance.
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Affiliation(s)
- Pirmin Nietlisbach
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
| | - Jarrod D Hadfield
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JT, United Kingdom
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Nietlisbach P, Camenisch G, Bucher T, Slate J, Keller LF, Postma E. A microsatellite-based linkage map for song sparrows (Melospiza melodia). Mol Ecol Resour 2015; 15:1486-96. [PMID: 25865627 DOI: 10.1111/1755-0998.12414] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 04/01/2015] [Accepted: 04/03/2015] [Indexed: 01/15/2023]
Abstract
Although linkage maps are important tools in evolutionary biology, their availability for wild populations is limited. The population of song sparrows (Melospiza melodia) on Mandarte Island, Canada, is among the more intensively studied wild animal populations. Its long-term pedigree data, together with extensive genetic sampling, have allowed the study of a range of questions in evolutionary biology and ecology. However, the availability of genetic markers has been limited. We here describe 191 new microsatellite loci, including 160 high-quality polymorphic autosomal, 7 Z-linked and 1 W-linked markers. We used these markers to construct a linkage map for song sparrows with a total sex-averaged map length of 1731 cM and covering 35 linkage groups, and hence, these markers cover most of the 38-40 chromosomes. Female and male map lengths did not differ significantly. We then bioinformatically mapped these loci to the zebra finch (Taeniopygia guttata) genome and found that linkage groups were conserved between song sparrows and zebra finches. Compared to the zebra finch, marker order within small linkage groups was well conserved, whereas the larger linkage groups showed some intrachromosomal rearrangements. Finally, we show that as expected, recombination frequency between linked loci explained the majority of variation in gametic phase disequilibrium. Yet, there was substantial overlap in gametic phase disequilibrium between pairs of linked and unlinked loci. Given that the microsatellites described here lie on 35 of the 38-40 chromosomes, these markers will be useful for studies in this species, as well as for comparative genomics studies with other species.
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Affiliation(s)
- Pirmin Nietlisbach
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Glauco Camenisch
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Thomas Bucher
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Jon Slate
- Department of Animal & Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Lukas F Keller
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Erik Postma
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
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Reid JM, Arcese P, Keller LF, Germain RR, Duthie AB, Losdat S, Wolak ME, Nietlisbach P. Quantifying inbreeding avoidance through extra-pair reproduction. Evolution 2014; 69:59-74. [PMID: 25346331 PMCID: PMC4312944 DOI: 10.1111/evo.12557] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 10/11/2014] [Indexed: 01/13/2023]
Abstract
Extra-pair reproduction is widely hypothesized to allow females to avoid inbreeding with related socially paired males. Consequently, numerous field studies have tested the key predictions that extra-pair offspring are less inbred than females’ alternative within-pair offspring, and that the probability of extra-pair reproduction increases with a female's relatedness to her socially paired male. However, such studies rarely measure inbreeding or relatedness sufficiently precisely to detect subtle effects, or consider biases stemming from failure to observe inbred offspring that die during early development. Analyses of multigenerational song sparrow (Melospiza melodia) pedigree data showed that most females had opportunity to increase or decrease the coefficient of inbreeding of their offspring through extra-pair reproduction with neighboring males. In practice, observed extra-pair offspring had lower inbreeding coefficients than females’ within-pair offspring on average, while the probability of extra-pair reproduction increased substantially with the coefficient of kinship between a female and her socially paired male. However, simulations showed that such effects could simply reflect bias stemming from inbreeding depression in early offspring survival. The null hypothesis that extra-pair reproduction is random with respect to kinship therefore cannot be definitively rejected in song sparrows, and existing general evidence that females avoid inbreeding through extra-pair reproduction requires reevaluation given such biases.
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Affiliation(s)
- Jane M Reid
- School of Biological Sciences, Institute of Biological and Environmental Sciences, Zoology Building, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland.
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Reid JM, Keller LF, Marr AB, Nietlisbach P, Sardell RJ, Arcese P. Pedigree error due to extra-pair reproduction substantially biases estimates of inbreeding depression. Evolution 2013; 68:802-15. [PMID: 24171712 DOI: 10.1111/evo.12305] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 10/17/2013] [Indexed: 11/28/2022]
Abstract
Understanding the evolutionary dynamics of inbreeding and inbreeding depression requires unbiased estimation of inbreeding depression across diverse mating systems. However, studies estimating inbreeding depression often measure inbreeding with error, for example, based on pedigree data derived from observed parental behavior that ignore paternity error stemming from multiple mating. Such paternity error causes error in estimated coefficients of inbreeding (f) and reproductive success and could bias estimates of inbreeding depression. We used complete "apparent" pedigree data compiled from observed parental behavior and analogous "actual" pedigree data comprising genetic parentage to quantify effects of paternity error stemming from extra-pair reproduction on estimates of f, reproductive success, and inbreeding depression in free-living song sparrows (Melospiza melodia). Paternity error caused widespread error in estimates of f and male reproductive success, causing inbreeding depression in male and female annual and lifetime reproductive success and juvenile male survival to be substantially underestimated. Conversely, inbreeding depression in adult male survival tended to be overestimated when paternity error was ignored. Pedigree error stemming from extra-pair reproduction therefore caused substantial and divergent bias in estimates of inbreeding depression that could bias tests of evolutionary theories regarding inbreeding and inbreeding depression and their links to variation in mating system.
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Affiliation(s)
- Jane M Reid
- Institute of Biological and Environmental Sciences, School of Biological Sciences, Zoology Building, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland.
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Nietlisbach P, Wandeler P, Parker PG, Grant PR, Grant BR, Keller LF, Hoeck PEA. Hybrid ancestry of an island subspecies of Galápagos mockingbird explains discordant gene trees. Mol Phylogenet Evol 2013; 69:581-92. [PMID: 23906599 DOI: 10.1016/j.ympev.2013.07.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 07/17/2013] [Accepted: 07/18/2013] [Indexed: 11/28/2022]
Abstract
Introgression of genes through hybridization has been proposed to be an important driver of speciation, but in animals this has been shown only in relatively few cases until recently. Additionally, introgressive hybridization among non-sister species leads to a change in the gene tree topology of the concerned loci and thus complicates phylogenetic reconstruction. However, such cases of ancient introgression have been very difficult to demonstrate in birds. Here, we present such an example in an island bird subspecies, the Genovesa mockingbird (Mimus parvulus bauri). We assessed phylogenetic relationships and population structure among mockingbirds of the Galápagos archipelago using mitochondrial and nuclear DNA sequences, autosomal microsatellites, and morphological measurements. Mitochondrial haplotypes of Genovesa mockingbirds clustered closely with the haplotypes from two different species, San Cristóbal (M. melanotis) and Española (M. macdonaldi) mockingbirds. The same pattern was found for some haplotypes of two nuclear gene introns, while the majority of nuclear haplotypes of Genovesa mockingbirds were shared with other populations of the same species (M. parvulus). At 26 autosomal microsatellites, Genovesa mockingbirds grouped with other M. parvulus populations. This pattern shows that Genovesa mockingbirds contain mitochondria and some autosomal alleles that have most likely introgressed from M. melanotis into a largely M. parvulus background, making Genovesa mockingbirds a lineage of mixed ancestry, possibly undergoing speciation. Consistent with this hypothesis, mockingbirds on Genovesa are more clearly differentiated morphologically from other M. parvulus populations than M. melanotis is from M. parvulus.
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Affiliation(s)
- Pirmin Nietlisbach
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
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Nietlisbach P, Arora N, Nater A, Goossens B, Van Schaik CP, Krützen M. Heavily male-biased long-distance dispersal of orang-utans (genus: Pongo), as revealed by Y-chromosomal and mitochondrial genetic markers. Mol Ecol 2012; 21:3173-86. [PMID: 22463133 DOI: 10.1111/j.1365-294x.2012.05539.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mating systems are thought to be an important determinant of dispersal strategies in most animals, including the great apes. As the most basal taxon of all great apes, orang-utans can provide information about the evolution of mating systems and their consequences for population structure in this Family. To assess the sex-specific population structure in orang-utans, we used a combination of paternally transmitted Y-chromosomal genetic markers and maternally transmitted mitochondrial DNA sequences. Markers transmitted through the more philopatric sex are expected to show stronger differentiation among populations than the ones transmitted through the dispersing sex. We studied these patterns using 70 genetic samples from wild orang-utans from seven Bornean and two Sumatran populations. We found pronounced population structure in haplotype networks of mitochondrial sequence data, but much less so for male-specific markers. Similarly, mitochondrial genetic differentiation was twice as high among populations compared to Y-chromosomal variation. We also found that genetic distance increased faster with geographic distance for mitochondrial than for Y-linked markers, leading to estimates of male dispersal distances that are several-fold higher than those of females. These findings provide evidence for strong male-biased dispersal in orang-utans. The transition to predominantly female-biased dispersal in the great ape lineage appears to be correlated with life in multimale groups and may reflect the associated fitness benefits of reliable male coalitions with relatives or known partners, a feature that is absent in orang-utans.
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Affiliation(s)
- Pirmin Nietlisbach
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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Nater A, Nietlisbach P, Arora N, van Schaik CP, van Noordwijk MA, Willems EP, Singleton I, Wich SA, Goossens B, Warren KS, Verschoor EJ, Perwitasari-Farajallah D, Pamungkas J, Krützen M. Sex-Biased Dispersal and Volcanic Activities Shaped Phylogeographic Patterns of Extant Orangutans (genus: Pongo). Mol Biol Evol 2011; 28:2275-88. [DOI: 10.1093/molbev/msr042] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
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