1
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Affiliation(s)
- Eric Edeline
- Sorbonne Université/UPMC Univ. Paris 06/CNRS/INRA/IRD/Paris Diderot Univ. Paris 07/UPEC/Institut d'Ecologie et des Sciences de l'Environnement – Paris (iEES‐Paris) Paris France
- ESE Ecology and Ecosystem Health, INRAE, Agocampus Ouest Rennes France
| | - Nicolas Loeuille
- Sorbonne Université/UPMC Univ. Paris 06/CNRS/INRA/IRD/Paris Diderot Univ. Paris 07/UPEC/Institut d'Ecologie et des Sciences de l'Environnement – Paris (iEES‐Paris) Paris France
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2
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Frank SC, Pelletier F, Kopatz A, Bourret A, Garant D, Swenson JE, Eiken HG, Hagen SB, Zedrosser A. Harvest is associated with the disruption of social and fine-scale genetic structure among matrilines of a solitary large carnivore. Evol Appl 2021; 14:1023-1035. [PMID: 33897818 PMCID: PMC8061280 DOI: 10.1111/eva.13178] [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: 07/31/2020] [Revised: 11/13/2020] [Accepted: 11/16/2020] [Indexed: 11/27/2022] Open
Abstract
Harvest can disrupt wildlife populations by removing adults with naturally high survival. This can reshape sociospatial structure, genetic composition, fitness, and potentially affect evolution. Genetic tools can detect changes in local, fine-scale genetic structure (FGS) and assess the interplay between harvest-caused social and FGS in populations. We used data on 1614 brown bears, Ursus arctos, genotyped with 16 microsatellites, to investigate whether harvest intensity (mean low: 0.13 from 1990 to 2005, mean high: 0.28 from 2006 to 2011) caused changes in FGS among matrilines (8 matrilines; 109 females ≥4 years of age), sex-specific survival and putative dispersal distances, female spatial genetic autocorrelation, matriline persistence, and male mating patterns. Increased harvest decreased FGS of matrilines. Female dispersal distances decreased, and male reproductive success was redistributed more evenly. Adult males had lower survival during high harvest, suggesting that higher male turnover caused this redistribution and helped explain decreased structure among matrilines, despite shorter female dispersal distances. Adult female survival and survival probability of both mother and daughter were lower during high harvest, indicating that matriline persistence was also lower. Our findings indicate a crucial role of regulated harvest in shaping populations, decreasing differences among "groups," even for solitary-living species, and potentially altering the evolutionary trajectory of wild populations.
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Affiliation(s)
- Shane C. Frank
- Department of Natural Sciences and Environmental HealthUniversity of South‐Eastern NorwayTelemarkNorway
| | - Fanie Pelletier
- Département de BiologieUniversité de SherbrookeSherbrookeQCCanada
| | | | - Audrey Bourret
- Département de BiologieUniversité de SherbrookeSherbrookeQCCanada
| | - Dany Garant
- Département de BiologieUniversité de SherbrookeSherbrookeQCCanada
| | - Jon E. Swenson
- Faculty of Environmental Sciences and Natural Resource ManagementNorwegian University of Life SciencesÅsNorway
| | | | | | - Andreas Zedrosser
- Department of Natural Sciences and Environmental HealthUniversity of South‐Eastern NorwayTelemarkNorway
- Institute of Wildlife Biology and Game ManagementUniversity of Natural Resources and Applied Life SciencesViennaAustria
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3
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Bouffet-Halle A, Mériguet J, Carmignac D, Agostini S, Millot A, Perret S, Motard E, Decenciere B, Edeline E. Density-dependent natural selection mediates harvest-induced trait changes. Ecol Lett 2021; 24:648-657. [PMID: 33511789 DOI: 10.1111/ele.13677] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/13/2020] [Accepted: 08/16/2020] [Indexed: 11/28/2022]
Abstract
Rapid life-history changes caused by size-selective harvesting are often interpreted as a response to direct harvest selection against a large body size. However, similar trait changes may result from a harvest-induced relaxation of natural selection for a large body size via density-dependent selection. Here, we show evidence of such density-dependent selection favouring large-bodied individuals at high population densities, in replicated pond populations of medaka fish. Harvesting, in contrast, selected medaka directly against a large body size and, in parallel, decreased medaka population densities. Five years of harvesting were enough for harvested and unharvested medaka populations to inherit the classically predicted trait differences, whereby harvested medaka grew slower and matured earlier than unharvested medaka. We show that this life-history divergence was not driven by direct harvest selection for a smaller body size in harvested populations, but by density-dependent natural selection for a larger body size in unharvested populations.
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Affiliation(s)
- Alix Bouffet-Halle
- Sorbonne Université, Université Paris Diderot, UPEC, CNRS, INRA, IRD, Institut d'Ecologie et des Sciences de l'Environnement de Paris (iEES-Paris), Paris, F-75252, France
| | - Jacques Mériguet
- CEREEP Ecotron Île-de-France, UMS CNRS/ENS 3194, 78 rue du Château, Saint-Pierre-lès-Nemours, 77140, France.,Institut de Biologie de l'Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 46 rue d'Ulm, Paris, 75005, France
| | - David Carmignac
- Sorbonne Université, Université Paris Diderot, UPEC, CNRS, INRA, IRD, Institut d'Ecologie et des Sciences de l'Environnement de Paris (iEES-Paris), Paris, F-75252, France
| | - Simon Agostini
- CEREEP Ecotron Île-de-France, UMS CNRS/ENS 3194, 78 rue du Château, Saint-Pierre-lès-Nemours, 77140, France
| | - Alexis Millot
- CEREEP Ecotron Île-de-France, UMS CNRS/ENS 3194, 78 rue du Château, Saint-Pierre-lès-Nemours, 77140, France
| | - Samuel Perret
- CEREEP Ecotron Île-de-France, UMS CNRS/ENS 3194, 78 rue du Château, Saint-Pierre-lès-Nemours, 77140, France.,Centre d'Ecologie Fonctionnelle et Evolutive CEFE, UMR 5175, Campus CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, Montpellier, Cedex 5, France
| | - Eric Motard
- Sorbonne Université, Université Paris Diderot, UPEC, CNRS, INRA, IRD, Institut d'Ecologie et des Sciences de l'Environnement de Paris (iEES-Paris), Paris, F-75252, France
| | - Beatriz Decenciere
- CEREEP Ecotron Île-de-France, UMS CNRS/ENS 3194, 78 rue du Château, Saint-Pierre-lès-Nemours, 77140, France
| | - Eric Edeline
- Sorbonne Université, Université Paris Diderot, UPEC, CNRS, INRA, IRD, Institut d'Ecologie et des Sciences de l'Environnement de Paris (iEES-Paris), Paris, F-75252, France.,ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, Rennes, France
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4
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Ofstad EG, Markussen SS, Sæther B, Solberg EJ, Heim M, Haanes H, Røed KH, Herfindal I. Opposing fitness consequences of habitat use in a harvested moose population. J Anim Ecol 2020; 89:1701-1710. [DOI: 10.1111/1365-2656.13221] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 02/17/2020] [Indexed: 11/29/2022]
Affiliation(s)
- Endre Grüner Ofstad
- Department of Biology Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
| | - Stine S. Markussen
- Department of Biology Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
| | - Bernt‐Erik Sæther
- Department of Biology Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
| | | | - Morten Heim
- Norwegian Institute for Nature Research (NINA) Trondheim Norway
| | | | - Knut H. Røed
- Department of Basic Sciences and Aquatic Medicine Norwegian University of Life Sciences Oslo Norway
| | - Ivar Herfindal
- Department of Biology Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
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5
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Braverman E, Ilmer I. On the interplay of harvesting and various diffusion strategies for spatially heterogeneous populations. J Theor Biol 2019; 466:106-118. [PMID: 30690036 DOI: 10.1016/j.jtbi.2019.01.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/17/2019] [Accepted: 01/24/2019] [Indexed: 11/18/2022]
Abstract
The paper explores the influence of harvesting (or culling) on the outcome of the competition of two species in a spatially heterogeneous environment. The harvesting effort is assumed to be proportional to the space-dependent intrinsic growth rate. The differences between the two populations are the diffusion strategy and the harvesting intensity. In the absence of harvesting, competing populations may either coexist, or one of them may bring the other to extinction. If the latter is the case, introduction of any level of harvesting to the successful species guarantees survival to its non-harvested competitor. In the former case, there is a strip of "close enough" to each other harvesting rates leading to preservation of the original coexistence. Some estimates are obtained for the relation of the harvesting levels providing either coexistence or competitive exclusion.
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Affiliation(s)
- Elena Braverman
- Department of Math. and Stats., University of Calgary, 2500 University Drive N.W., Calgary, AB T2N 1N4, Canada.
| | - Ilia Ilmer
- Department of Math. and Stats., University of Calgary, 2500 University Drive N.W., Calgary, AB T2N 1N4, Canada; Department of Computer Science, City University of New York-College of Staten Island, The Graduate Center of City University of New York, 365 Fifth Avenue, New York 10314, United States
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6
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7
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Hunting regulation favors slow life histories in a large carnivore. Nat Commun 2018; 9:1100. [PMID: 29588441 PMCID: PMC5871616 DOI: 10.1038/s41467-018-03506-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 02/20/2018] [Indexed: 11/18/2022] Open
Abstract
As an important extrinsic source of mortality, harvest should select for fast reproduction and accelerated life histories. However, if vulnerability to harvest depends upon female reproductive status, patterns of selectivity could diverge and favor alternative reproductive behaviors. Here, using more than 20 years of detailed data on survival and reproduction in a hunted large carnivore population, we show that protecting females with dependent young, a widespread hunting regulation, provides a survival benefit to females providing longer maternal care. This survival gain compensates for the females’ reduced reproductive output, especially at high hunting pressure, where the fitness benefit of prolonged periods of maternal care outweighs that of shorter maternal care. Our study shows that hunting regulation can indirectly promote slower life histories by modulating the fitness benefit of maternal care tactics. We provide empirical evidence that harvest regulation can induce artificial selection on female life history traits and affect demographic processes. Hunting and harvesting are generally expected to select for faster life histories in the exploited species. Here, the authors analyse data from a hunted population of brown bears in Sweden and show that regulations protecting females with dependent young lead hunting to favor prolonged maternal care.
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8
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Kuparinen A, Festa-Bianchet M. Harvest-induced evolution: insights from aquatic and terrestrial systems. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2016.0036. [PMID: 27920381 DOI: 10.1098/rstb.2016.0036] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/04/2016] [Indexed: 12/29/2022] Open
Abstract
Commercial and recreational harvests create selection pressures for fitness-related phenotypic traits that are partly under genetic control. Consequently, harvesting can drive evolution in targeted traits. However, the quantification of harvest-induced evolutionary life history and phenotypic changes is challenging, because both density-dependent feedback and environmental changes may also affect these changes through phenotypic plasticity. Here, we synthesize current knowledge and uncertainties on six key points: (i) whether or not harvest-induced evolution is happening, (ii) whether or not it is beneficial, (iii) how it shapes biological systems, (iv) how it could be avoided, (v) its importance relative to other drivers of phenotypic changes, and (vi) whether or not it should be explicitly accounted for in management. We do this by reviewing findings from aquatic systems exposed to fishing and terrestrial systems targeted by hunting. Evidence from aquatic systems emphasizes evolutionary effects on age and size at maturity, while in terrestrial systems changes are seen in weapon size and date of parturition. We suggest that while harvest-induced evolution is likely to occur and negatively affect populations, the rate of evolutionary changes and their ecological implications can be managed efficiently by simply reducing harvest intensity.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'.
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Affiliation(s)
- Anna Kuparinen
- Department of Environmental Sciences, University of Helsinki, PO Box 65, 00014 Helsinki, Finland
| | - Marco Festa-Bianchet
- Département de biologie, Université de Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1
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9
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Evolution of stochastic demography with life history tradeoffs in density-dependent age-structured populations. Proc Natl Acad Sci U S A 2017; 114:11582-11590. [PMID: 29078347 DOI: 10.1073/pnas.1710679114] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We analyze the stochastic demography and evolution of a density-dependent age- (or stage-) structured population in a fluctuating environment. A positive linear combination of age classes (e.g., weighted by body mass) is assumed to act as the single variable of population size, [Formula: see text], exerting density dependence on age-specific vital rates through an increasing function of population size. The environment fluctuates in a stationary distribution with no autocorrelation. We show by analysis and simulation of age structure, under assumptions often met by vertebrate populations, that the stochastic dynamics of population size can be accurately approximated by a univariate model governed by three key demographic parameters: the intrinsic rate of increase and carrying capacity in the average environment, [Formula: see text] and [Formula: see text], and the environmental variance in population growth rate, [Formula: see text] Allowing these parameters to be genetically variable and to evolve, but assuming that a fourth parameter, [Formula: see text], measuring the nonlinearity of density dependence, remains constant, the expected evolution maximizes [Formula: see text] This shows that the magnitude of environmental stochasticity governs the classical trade-off between selection for higher [Formula: see text] versus higher [Formula: see text] However, selection also acts to decrease [Formula: see text], so the simple life-history trade-off between [Formula: see text]- and [Formula: see text]-selection may be obscured by additional trade-offs between them and [Formula: see text] Under the classical logistic model of population growth with linear density dependence ([Formula: see text]), life-history evolution in a fluctuating environment tends to maximize the average population size.
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10
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Engen S, Sæther BE. Extinction Risk and Lack of Evolutionary Rescue under Resource Depletion or Area Reduction. Am Nat 2017; 190:73-82. [DOI: 10.1086/692011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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11
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Caudill D, Guttery MR, Terhune TM, Martin JA, Caudill G, Dahlgren DK, Messmer TA. Individual heterogeneity and effects of harvest on greater sage-grouse populations. J Wildl Manage 2017. [DOI: 10.1002/jwmg.21241] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Danny Caudill
- Department of Wildland Resources; Utah State University; Logan UT 84322-5230 USA
| | - Michael R. Guttery
- Department of Wildland Resources; Utah State University; Logan UT 84322-5230 USA
| | - Theron M. Terhune
- Tall Timbers Research Station and Land Conservancy; Tallahassee FL 32312 USA
| | - James A. Martin
- Warnell School of Forestry and Natural Resources, Savannah River Ecology Lab; University of Georgia; Athens GA 30605 USA
| | - Gretchen Caudill
- Fish and Wildlife Research Institute; Florida Fish and Wildlife Conservation Commission; Gainesville FL 32601 USA
| | - David K. Dahlgren
- Department of Wildland Resources; Utah State University; Logan UT 84322-5230 USA
| | - Terry A. Messmer
- Jack H. Berryman Institute, Department of Wildland Resources; Utah State University; Logan UT 84322-5230 USA
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12
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Sæther BE, Visser ME, Grøtan V, Engen S. Evidence for r- and K-selection in a wild bird population: a reciprocal link between ecology and evolution. Proc Biol Sci 2017; 283:rspb.2015.2411. [PMID: 27122550 DOI: 10.1098/rspb.2015.2411] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 04/04/2016] [Indexed: 12/20/2022] Open
Abstract
Understanding the variation in selection pressure on key life-history traits is crucial in our rapidly changing world. Density is rarely considered as a selective agent. To study its importance, we partition phenotypic selection in fluctuating environments into components representing the population growth rate at low densities and the strength of density dependence, using a new stochastic modelling framework. We analysed the number of eggs laid per season in a small song-bird, the great tit, and found balancing selection favouring large clutch sizes at small population densities and smaller clutches in years with large populations. A significant interaction between clutch size and population size in the regression for the Malthusian fitness reveals that those females producing large clutch sizes at small population sizes also are those that show the strongest reduction in fitness when population size is increased. This provides empirical support for ongoing r- and K-selection in this population, favouring phenotypes with large growth rates r at small population sizes and phenotypes with high competitive skills when populations are close to the carrying capacity K This selection causes long-term fluctuations around a stable mean clutch size caused by variation in population size, implying that r- and K-selection is an important mechanism influencing phenotypic evolution in fluctuating environments. This provides a general link between ecological dynamics and evolutionary processes, operating through a joint influence of density dependence and environmental stochasticity on fluctuations in population size.
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Affiliation(s)
- Bernt-Erik Sæther
- Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, Trondheim 7491, Norway
| | - Marcel E Visser
- Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), PO Box 50, Wageningen 6700 AB, The Netherlands
| | - Vidar Grøtan
- Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, Trondheim 7491, Norway
| | - Steinar Engen
- Centre for Biodiversity Dynamics, Department of Mathematical Sciences, Norwegian University of Science and Technology, Trondheim 7491, Norway
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13
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Kvalnes T, Saether BE, Haanes H, Røed KH, Engen S, Solberg EJ. Harvest-induced phenotypic selection in an island population of moose, Alces alces. Evolution 2016; 70:1486-500. [PMID: 27174031 DOI: 10.1111/evo.12952] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 04/29/2016] [Indexed: 01/20/2023]
Abstract
Empirical evidence strongly indicates that human exploitation has frequently led to rapid evolutionary changes in wild populations, yet the mechanisms involved are often poorly understood. Here, we applied a recently developed demographic framework for analyzing selection to data from a 20-year study of a wild population of moose, Alces alces. In this population, a genetic pedigree has been established all the way back to founders. We demonstrate harvest-induced directional selection for delayed birth dates in males and reduced body mass as calf in females. During the study period, birth date was delayed by 0.81 days per year for both sexes, whereas no significant changes occurred in calf body mass. Quantitative genetic analyses indicated that both traits harbored significant additive genetic variance. These results show that selective harvesting can induce strong selection that oppose natural selection. This may cause evolution of less favorable phenotypes that become maladaptive once harvesting ceases.
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Affiliation(s)
- Thomas Kvalnes
- Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway.
| | - Bernt-Erik Saether
- Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Hallvard Haanes
- Norwegian Radiation Protection Authority, NO-1361 Østerås, Norway
| | - Knut H Røed
- Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, PO-8146 Dep, NO-0033 Oslo, Norway
| | - Steinar Engen
- Centre for Biodiversity Dynamics (CBD), Department of Mathematical Sciences, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Erling J Solberg
- Norwegian Institute for Nature Research (NINA), NO-7485 Trondheim, Norway
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14
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Engen S, Saether BE. Optimal age of maturity in fluctuating environments underr- andK-selection. OIKOS 2016. [DOI: 10.1111/oik.03111] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Steinar Engen
- Dept of Mathematical Sciences; Centre for Biodiversity Dynamics, Norwegian Univ. of Science and Technology; NO-7491 Trondheim Norway
| | - Bernt-Erik Saether
- Dept of Biology; Centre for Biodiversity Dynamics, Norwegian Univ. of Science and Technology; NO-7491-Trondheim Norway
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15
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Chiyo PI, Obanda V, Korir DK. Illegal tusk harvest and the decline of tusk size in the African elephant. Ecol Evol 2015; 5:5216-5229. [PMID: 30151125 PMCID: PMC6102531 DOI: 10.1002/ece3.1769] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 08/08/2015] [Accepted: 09/10/2015] [Indexed: 11/30/2022] Open
Abstract
Harvesting of wild populations can cause the evolution of morphological, behavioral, and life history traits that may compromise natural or sexual selection. Despite the vulnerability of large mammals to rapid population decline from harvesting, the evolutionary effects of harvesting on mega‐fauna have received limited attention. In elephants, illegal ivory harvesting disproportionately affects older age classes and males because they carry large tusks, but its' effects on tusk size for age or tusk size for stature are less understood. We tested whether severe historical elephant harvests eliminated large tuskers among survivors and whether elephants born thereafter had smaller tusks. Adjusting for the influence of shoulder height – a metric strongly correlated with body size and age and often used as a proxy for age – we compared tusk size for elephants sampled in 1966–1968, prior to severe ivory harvesting in the late 1970s and early 1980s, with tusk size of survivors and elephants born during population recovery in the mid‐1990s. In a regional population, tusk length declined by ˜21% in male and by ˜27% in female elephants born during population recovery, while tusk length declined by 22% in males and 37% in females among survivors. Tusk circumference at lip declined by 5% in males but not in females born during population recovery, whereas tusk circumference reduced by 8% in male and by 11% in female survivors. In a single subpopulation, mean tusk length at mean basal tusk circumference declined by 12.4% in males and 21% in females. Tusk size varied between elephant social groups. Tusk homogeneity within social groups and the often high genetic similarity within social groups suggest that tusk size may be heritable. Our findings support a hypothesis of selection of large tuskers by poachers as a driver of the decline in tusk size for age proxy and contemporary tusk evolution in African elephants.
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Affiliation(s)
- Patrick I Chiyo
- Department of Biology Duke University Box 90338 Durham North Carolina 27708
| | - Vincent Obanda
- Veterinary Services Department Kenya Wildlife Service P.O. Box 40241-00100 Nairobi Kenya
| | - David K Korir
- Biodiversity Monitoring & Research Division Kenya Wildlife Service Masai Mara Research Station P.O. Box 72-20500 Narok Kenya
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16
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Uusi-Heikkilä S, Whiteley AR, Kuparinen A, Matsumura S, Venturelli PA, Wolter C, Slate J, Primmer CR, Meinelt T, Killen SS, Bierbach D, Polverino G, Ludwig A, Arlinghaus R. The evolutionary legacy of size-selective harvesting extends from genes to populations. Evol Appl 2015; 8:597-620. [PMID: 26136825 PMCID: PMC4479515 DOI: 10.1111/eva.12268] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 04/05/2015] [Indexed: 12/18/2022] Open
Abstract
Size-selective harvesting is assumed to alter life histories of exploited fish populations, thereby negatively affecting population productivity, recovery, and yield. However, demonstrating that fisheries-induced phenotypic changes in the wild are at least partly genetically determined has proved notoriously difficult. Moreover, the population-level consequences of fisheries-induced evolution are still being controversially discussed. Using an experimental approach, we found that five generations of size-selective harvesting altered the life histories and behavior, but not the metabolic rate, of wild-origin zebrafish (Danio rerio). Fish adapted to high positively size selective fishing pressure invested more in reproduction, reached a smaller adult body size, and were less explorative and bold. Phenotypic changes seemed subtle but were accompanied by genetic changes in functional loci. Thus, our results provided unambiguous evidence for rapid, harvest-induced phenotypic and evolutionary change when harvesting is intensive and size selective. According to a life-history model, the observed life-history changes elevated population growth rate in harvested conditions, but slowed population recovery under a simulated moratorium. Hence, the evolutionary legacy of size-selective harvesting includes populations that are productive under exploited conditions, but selectively disadvantaged to cope with natural selection pressures that often favor large body size.
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Affiliation(s)
- Silva Uusi-Heikkilä
- Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany ; Division of Genetics and Physiology, Department of Biology, University of Turku Turku, Finland
| | - Andrew R Whiteley
- Department of Environmental Conservation, University of Massachusetts Amherst, MA, USA
| | - Anna Kuparinen
- Department of Environmental Sciences, University of Helsinki Helsinki, Finland
| | | | - Paul A Venturelli
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota St Paul, MN, USA
| | - Christian Wolter
- Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany
| | - Jon Slate
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank Sheffield, UK
| | - Craig R Primmer
- Division of Genetics and Physiology, Department of Biology, University of Turku Turku, Finland
| | - Thomas Meinelt
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany
| | - Shaun S Killen
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow Glasgow, UK
| | - David Bierbach
- Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany
| | - Giovanni Polverino
- Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany
| | - Arne Ludwig
- Department of Evolutionary Genetics, Leibniz-Institute for Zoo and Wildlife Research Berlin, Germany
| | - Robert Arlinghaus
- Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Germany ; Chair of Integrative Fisheries Management, Faculty of Life Sciences, Albrecht-Daniel-Thaer Institute of Agricultural and Horticultural Sciences, Humboldt-Universität zu Berlin Berlin, Germany
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