Natural selection for body shape in resource polymorphic Icelandic Arctic charr
Abstract Resource polymorphisms exhibit remarkable intraspecific diversity and in many cases are expected to be maintained by diversifying selection. Phenotypic trade‐offs can constrain morphologically intermediate individuals from effectively exploiting both alternate resources, resulting in ecolog...
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Oxford University Press (OUP)
2018
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Online Access: | http://dx.doi.org/10.1111/jeb.13346 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjeb.13346 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jeb.13346 |
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croxfordunivpr:10.1111/jeb.13346 2024-09-15T17:52:23+00:00 Natural selection for body shape in resource polymorphic Icelandic Arctic charr Franklin, Oliver D. Skúlason, Skúli Morrissey, Michael B. Ferguson, Moira M. Natural Sciences and Engineering Research Council of Canada 2018 http://dx.doi.org/10.1111/jeb.13346 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjeb.13346 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jeb.13346 en eng Oxford University Press (OUP) http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Evolutionary Biology volume 31, issue 10, page 1498-1512 ISSN 1010-061X 1420-9101 journal-article 2018 croxfordunivpr https://doi.org/10.1111/jeb.13346 2024-08-12T04:22:35Z Abstract Resource polymorphisms exhibit remarkable intraspecific diversity and in many cases are expected to be maintained by diversifying selection. Phenotypic trade‐offs can constrain morphologically intermediate individuals from effectively exploiting both alternate resources, resulting in ecological barriers to gene flow. Determining if and how phenotypic trade‐offs cause fitness variation in the wild is challenging because of phenotypic and environmental correlations associated with alternative resource strategies. We investigated multiple pathways through which morphology could affect organismal performance, as measured by growth rate, and whether these effects generate diversifying selection in polymorphic Icelandic Arctic charr ( Salvelinus alpinus ) populations. We considered direct effects of morphology on growth and indirect effects via trophic resource use, estimated by stable isotopic signatures, and via parasitism associated with trophic resources. We sampled over 3 years in (lakes) Thingvallavatn and Vatnshlíðarvatn using the extended selection gradient path analytical approach and estimating size‐dependent mortality. We found evidence for diversifying selection only in Thingvallavatn: more streamlined and terminally mouthed planktivore charr experienced greater growth, with the opposite pattern in small benthic charr. However, this effect was mediated by parasitism and nontrophic pathways, rather than trophic performance as often expected. Detection of between‐morph differences in the presence (Vatnshlíðarvatn) and direction (Thingvallavatn) of size‐dependent mortality, together with nontrophic effects of shape, suggests that a morphological trophic performance explanation for polymorphism is insufficient. This rare insight into selection during early diversification suggests that a complex of interacting local factors must be considered to understand how phenotype influences fitness, despite morphological variation reflecting intuitive trade‐off explanations. Article in Journal/Newspaper Arctic charr Salvelinus alpinus Oxford University Press Journal of Evolutionary Biology 31 10 1498 1512 |
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Open Polar |
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Oxford University Press |
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croxfordunivpr |
language |
English |
description |
Abstract Resource polymorphisms exhibit remarkable intraspecific diversity and in many cases are expected to be maintained by diversifying selection. Phenotypic trade‐offs can constrain morphologically intermediate individuals from effectively exploiting both alternate resources, resulting in ecological barriers to gene flow. Determining if and how phenotypic trade‐offs cause fitness variation in the wild is challenging because of phenotypic and environmental correlations associated with alternative resource strategies. We investigated multiple pathways through which morphology could affect organismal performance, as measured by growth rate, and whether these effects generate diversifying selection in polymorphic Icelandic Arctic charr ( Salvelinus alpinus ) populations. We considered direct effects of morphology on growth and indirect effects via trophic resource use, estimated by stable isotopic signatures, and via parasitism associated with trophic resources. We sampled over 3 years in (lakes) Thingvallavatn and Vatnshlíðarvatn using the extended selection gradient path analytical approach and estimating size‐dependent mortality. We found evidence for diversifying selection only in Thingvallavatn: more streamlined and terminally mouthed planktivore charr experienced greater growth, with the opposite pattern in small benthic charr. However, this effect was mediated by parasitism and nontrophic pathways, rather than trophic performance as often expected. Detection of between‐morph differences in the presence (Vatnshlíðarvatn) and direction (Thingvallavatn) of size‐dependent mortality, together with nontrophic effects of shape, suggests that a morphological trophic performance explanation for polymorphism is insufficient. This rare insight into selection during early diversification suggests that a complex of interacting local factors must be considered to understand how phenotype influences fitness, despite morphological variation reflecting intuitive trade‐off explanations. |
author2 |
Natural Sciences and Engineering Research Council of Canada |
format |
Article in Journal/Newspaper |
author |
Franklin, Oliver D. Skúlason, Skúli Morrissey, Michael B. Ferguson, Moira M. |
spellingShingle |
Franklin, Oliver D. Skúlason, Skúli Morrissey, Michael B. Ferguson, Moira M. Natural selection for body shape in resource polymorphic Icelandic Arctic charr |
author_facet |
Franklin, Oliver D. Skúlason, Skúli Morrissey, Michael B. Ferguson, Moira M. |
author_sort |
Franklin, Oliver D. |
title |
Natural selection for body shape in resource polymorphic Icelandic Arctic charr |
title_short |
Natural selection for body shape in resource polymorphic Icelandic Arctic charr |
title_full |
Natural selection for body shape in resource polymorphic Icelandic Arctic charr |
title_fullStr |
Natural selection for body shape in resource polymorphic Icelandic Arctic charr |
title_full_unstemmed |
Natural selection for body shape in resource polymorphic Icelandic Arctic charr |
title_sort |
natural selection for body shape in resource polymorphic icelandic arctic charr |
publisher |
Oxford University Press (OUP) |
publishDate |
2018 |
url |
http://dx.doi.org/10.1111/jeb.13346 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjeb.13346 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jeb.13346 |
genre |
Arctic charr Salvelinus alpinus |
genre_facet |
Arctic charr Salvelinus alpinus |
op_source |
Journal of Evolutionary Biology volume 31, issue 10, page 1498-1512 ISSN 1010-061X 1420-9101 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1111/jeb.13346 |
container_title |
Journal of Evolutionary Biology |
container_volume |
31 |
container_issue |
10 |
container_start_page |
1498 |
op_container_end_page |
1512 |
_version_ |
1810294433681244160 |