15
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Are heritability and selection related to population size in nature? Meta‐analysis and conservation implications

      review-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          It is widely thought that small populations should have less additive genetic variance and respond less efficiently to natural selection than large populations. Across taxa, we meta‐analytically quantified the relationship between adult census population size ( N) and additive genetic variance (proxy: h 2) and found no reduction in h 2 with decreasing N; surveyed populations ranged from four to one million individuals (1735  h 2 estimates, 146 populations, 83 species). In terms of adaptation, ecological conditions may systematically differ between populations of varying N; the magnitude of selection these populations experience may therefore also differ. We thus also meta‐analytically tested whether selection changes with N and found little evidence for systematic differences in the strength, direction or form of selection with N across different trait types and taxa (7344 selection estimates, 172 populations, 80 species). Collectively, our results (i) indirectly suggest that genetic drift neither overwhelms selection more in small than in large natural populations, nor weakens adaptive potential/ h 2 in small populations, and (ii) imply that natural populations of varying sizes experience a variety of environmental conditions, without consistently differing habitat quality at small N. However, we caution that the data are currently insufficient to determine whether some small populations may retain adaptive potential definitively. Further study is required into (i) selection and genetic variation in completely isolated populations of known N, under‐represented taxonomic groups, and nongeneralist species, (ii) adaptive potential using multidimensional approaches and (iii) the nature of selective pressures for specific traits.

          Related collections

          Most cited references32

          • Record: found
          • Abstract: found
          • Article: not found

          Natural selection and the heritability of fitness components.

          The hypothesis that traits closely associated with fitness will generally possess lower heritabilities than traits more loosely connected with fitness is tested using 1120 narrow sense heritability estimates for wild, outbred animal populations, collected from the published record. Our results indicate that life history traits generally possess lower heritabilities than morphological traits, and that the means, medians, and cumulative frequency distributions of behavioural and physiological traits are intermediate between life history and morphological traits. These findings are consistent with popular interpretations of Fisher's (1930, 1958) Fundamental Theorem of Natural Selection, and Falconer (1960, 1981), but also indicate that high heritabilities are maintained within natural populations even for traits believed to be under strong selection. It is also found that the heritability of morphological traits is significantly lower for ectotherms than it is for endotherms which may in part be a result of the strong correlation between life history and body size for many ectotherms.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Estimating genetic parameters in natural populations using the "animal model".

            Estimating the genetic basis of quantitative traits can be tricky for wild populations in natural environments, as environmental variation frequently obscures the underlying evolutionary patterns. I review the recent application of restricted maximum-likelihood "animal models" to multigenerational data from natural populations, and show how the estimation of variance components and prediction of breeding values using these methods offer a powerful means of tackling the potentially confounding effects of environmental variation, as well as generating a wealth of new areas of investigation.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              It's about time: the temporal dynamics of phenotypic selection in the wild.

              Selection is a central process in nature. Although our understanding of the strength and form of selection has increased, a general understanding of the temporal dynamics of selection in nature is lacking. Here, we assembled a database of temporal replicates of selection from studies of wild populations to synthesize what we do (and do not) know about the temporal dynamics of selection. Our database contains 5519 estimates of selection from 89 studies, including estimates of both direct and indirect selection as well as linear and nonlinear selection. Morphological traits and studies focused on vertebrates were well-represented, with other traits and taxonomic groups less well-represented. Overall, three major features characterize the temporal dynamics of selection. First, the strength of selection often varies considerably from year to year, although random sampling error of selection coefficients may impose bias in estimates of the magnitude of such variation. Second, changes in the direction of selection are frequent. Third, changes in the form of selection are likely common, but harder to quantify. Although few studies have identified causal mechanisms underlying temporal variation in the strength, direction and form of selection, variation in environmental conditions driven by climatic fluctuations appear to be common and important.
                Bookmark

                Author and article information

                Journal
                Evol Appl
                Evol Appl
                10.1111/(ISSN)1752-4571
                EVA
                Evolutionary Applications
                John Wiley and Sons Inc. (Hoboken )
                1752-4571
                03 April 2016
                June 2016
                : 9
                : 5 ( doiID: 10.1111/eva.2016.9.issue-5 )
                : 640-657
                Affiliations
                [ 1 ] Department of BiologyConcordia University Montreal QCCanada
                [ 2 ] Group for Interuniversity Research in Limnology and Aquatic Environment (GRIL)Université du Québec à Trois‐Rivières Trois‐Rivières QCCanada
                Author notes
                [*] [* ] Correspondence

                Jacquelyn L. A. Wood, Department of Biology, Concordia University, 7141 Sherbrooke St. West, Montreal, QC, Canada H4B 1R6.

                Tel.: +1 514 848 2424;

                Fax: +1 514 848 2881;

                e‐mail: jackiewood7@ 123456gmail.com

                Article
                EVA12375
                10.1111/eva.12375
                4869407
                27247616
                65de6364-315a-4351-be58-3435e2d233ad
                © 2016 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.

                This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

                Page count
                Pages: 18
                Product
                Funding
                Funded by: NSERC Discovery Grant
                Funded by: NSERC Accelerator Award
                Funded by: NSERC PGS Scholarships
                Funded by: Concordia Graduate Fellowship
                Funded by: Group for interuniversity research in limnology and aquatic environment (GRIL) at the Université du Québec à Trois‐Rivières
                Categories
                Reviews and Syntheses
                Reviews and Syntheses
                Custom metadata
                2.0
                eva12375
                June 2016
                Converter:WILEY_ML3GV2_TO_NLMPMC version:4.8.9 mode:remove_FC converted:17.05.2016

                Evolutionary Biology
                adaptation,biodiversity conservation,effective population size,evolution,habitat fragmentation,heritability,natural selection

                Comments

                Comment on this article