Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes
The niche variation hypothesis predicts insular populations exhibit increased sexual size dimorphism (SSD), to minimize intraspecific competition. Although many animal taxa conform to this prediction, insular patterns of SSD have yet to be investigated in plants. Here, we tested for differences in S...
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crwiley:10.1111/oik.01753 2024-09-15T17:56:39+00:00 Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes Kavanagh, Patrick H. Burns, Kevin C. 2014 http://dx.doi.org/10.1111/oik.01753 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Foik.01753 https://onlinelibrary.wiley.com/doi/pdf/10.1111/oik.01753 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Oikos volume 124, issue 6, page 717-723 ISSN 0030-1299 1600-0706 journal-article 2014 crwiley https://doi.org/10.1111/oik.01753 2024-08-01T04:21:46Z The niche variation hypothesis predicts insular populations exhibit increased sexual size dimorphism (SSD), to minimize intraspecific competition. Although many animal taxa conform to this prediction, insular patterns of SSD have yet to be investigated in plants. Here, we tested for differences in SSD of dioecious plants that colonised four island groups (Kermadec, Three Kings, Chatham and Auckland Islands) from New Zealand. Using herbarium collections, we quantified leaf and stem sizes of 263 individuals from 28 dioecious taxa. We developed a novel analytical technique to explore changes in the direction of SSD on islands. Lastly, we tested for evolutionary size changes of male and female plants on islands. The degree of SSD did not vary predictably between insular and mainland taxa, contrary to predictions of the niche variation hypothesis. Furthermore, the direction of SSD was not predictable on islands, while it was consistently female biased on the mainland. Our results suggest that selection favours increased size of both sexes on islands and that SSD is unpredictable for insular plants. Article in Journal/Newspaper Auckland Islands Wiley Online Library Oikos 124 6 717 723 |
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Wiley Online Library |
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English |
description |
The niche variation hypothesis predicts insular populations exhibit increased sexual size dimorphism (SSD), to minimize intraspecific competition. Although many animal taxa conform to this prediction, insular patterns of SSD have yet to be investigated in plants. Here, we tested for differences in SSD of dioecious plants that colonised four island groups (Kermadec, Three Kings, Chatham and Auckland Islands) from New Zealand. Using herbarium collections, we quantified leaf and stem sizes of 263 individuals from 28 dioecious taxa. We developed a novel analytical technique to explore changes in the direction of SSD on islands. Lastly, we tested for evolutionary size changes of male and female plants on islands. The degree of SSD did not vary predictably between insular and mainland taxa, contrary to predictions of the niche variation hypothesis. Furthermore, the direction of SSD was not predictable on islands, while it was consistently female biased on the mainland. Our results suggest that selection favours increased size of both sexes on islands and that SSD is unpredictable for insular plants. |
format |
Article in Journal/Newspaper |
author |
Kavanagh, Patrick H. Burns, Kevin C. |
spellingShingle |
Kavanagh, Patrick H. Burns, Kevin C. Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes |
author_facet |
Kavanagh, Patrick H. Burns, Kevin C. |
author_sort |
Kavanagh, Patrick H. |
title |
Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes |
title_short |
Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes |
title_full |
Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes |
title_fullStr |
Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes |
title_full_unstemmed |
Sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes |
title_sort |
sexual size dimorphism in island plants: the niche variation hypothesis and insular size changes |
publisher |
Wiley |
publishDate |
2014 |
url |
http://dx.doi.org/10.1111/oik.01753 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Foik.01753 https://onlinelibrary.wiley.com/doi/pdf/10.1111/oik.01753 |
genre |
Auckland Islands |
genre_facet |
Auckland Islands |
op_source |
Oikos volume 124, issue 6, page 717-723 ISSN 0030-1299 1600-0706 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1111/oik.01753 |
container_title |
Oikos |
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124 |
container_issue |
6 |
container_start_page |
717 |
op_container_end_page |
723 |
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1810432838460243968 |