Dataset Information

Phenological mismatch drives selection on elevation, but not on slope, of breeding time plasticity in a wild songbird.

ABSTRACT: Phenotypic plasticity is an important mechanism for populations to respond to fluctuating environments, yet may be insufficient to adapt to a directionally changing environment. To study whether plasticity can evolve under current climate change, we quantified selection and genetic variation in both the elevation (RNE ) and slope (RNS ) of the breeding time reaction norm in a long-term (1973-2016) study population of great tits (Parus major). The optimal RNE (the caterpillar biomass peak date regressed against the temperature used as cue by great tits) changed over time, whereas the optimal RNS did not. Concordantly, we found strong directional selection on RNE , but not RNS , of egg-laying date in the second third of the study period; this selection subsequently waned, potentially due to increased between-year variability in optimal laying dates. We found individual and additive genetic variation in RNE but, contrary to previous studies on our population, not in RNS . The predicted and observed evolutionary change in RNE was, however, marginal, due to low heritability and the sex limitation of laying date. We conclude that adaptation to climate change can only occur via micro-evolution of RNE, but this will necessarily be slow and potentially hampered by increased variability in phenotypic optima.

SUBMITTER: Ramakers JJC

PROVIDER: S-EPMC6519030 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Phenological mismatch drives selection on elevation, but not on slope, of breeding time plasticity in a wild songbird.

Ramakers Jip J C JJC Gienapp Phillip P Visser Marcel E ME

Evolution; international journal of organic evolution 20181221 2

Phenotypic plasticity is an important mechanism for populations to respond to fluctuating environments, yet may be insufficient to adapt to a directionally changing environment. To study whether plasticity can evolve under current climate change, we quantified selection and genetic variation in both the elevation (RNE ) and slope (RNS ) of the breeding time reaction norm in a long-term (1973-2016) study population of great tits (Parus major). The optimal RNE (the ...[more]

PMID: 30556587

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Project description:Artificial selection experiments are a powerful tool in evolutionary biology. Selecting individuals based on multimarker genotypes (genomic selection) has several advantages over phenotype-based selection but has, so far, seen very limited use outside animal and plant breeding. Genomic selection depends on the markers tagging the causal loci that underlie the selected trait. Because the number of necessary markers depends, among other factors, on effective population size, genomic selection may be in practice not feasible in wild populations as most wild populations have much higher effective population sizes than domesticated populations. However, the current possibilities of cost-effective high-throughput genotyping could overcome this limitation and thereby make it possible to apply genomic selection also in wild populations. Using a unique dataset of about 2000 wild great tits (Parus major), a small passerine bird, genotyped on a 650 k SNP chip we calculated genomic breeding values for egg-laying date using the so-called GBLUP approach. In this approach, the pedigree-based relatedness matrix of an "animal model," a special form of the mixed model, is replaced by a marker-based relatedness matrix. Using the marker-based relatedness matrix, the model seemed better able to disentangle genetic and permanent environmental effects. We calculated the accuracy of genomic breeding values by correlating them to the phenotypes of individuals whose phenotypes were excluded from the analysis when estimating the genomic breeding values. The obtained accuracy was about 0.20, with very little effect of the used genomic relatedness estimator but a strong effect of the number of SNPs. The obtained accuracy is lower than typically seen in domesticated species but considerable for a trait with low heritability (∼0.2) as avian breeding time. Our results show that genomic selection is possible also in wild populations with potentially many applications, which we discuss here.

Dataset Information

Phenological mismatch drives selection on elevation, but not on slope, of breeding time plasticity in a wild songbird.

Publications

Phenological mismatch drives selection on elevation, but not on slope, of breeding time plasticity in a wild songbird.

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