Translator Disclaimer
1 December 2000 EVIDENCE OF ADAPTIVE DIVERGENCE IN PLASTICITY: DENSITY- AND SITE-DEPENDENT SELECTION ON SHADE-AVOIDANCE RESPONSES IN IMPATIENS CAPENSIS
Author Affiliations +
Abstract

We investigated the conditions under which plastic responses to density are adaptive in natural populations of Impatiens capensis and determined whether plasticity has evolved differently in different selective environments. Previous studies showed that a population that evolved in a sunny site exhibited greater plasticity in response to density than did a population that evolved in a woodland site. Using replicate inbred lines in a reciprocal transplant that included a density manipulation, we asked whether such population differentiation was consistent with the hypothesis of adaptive divergence. We hypothesized that plasticity would be more strongly favored in the sunny site than in the woodland site; consequently, we predicted that selection would be more strongly density dependent in the sunny site, favoring the phenotype that was expressed at each density. Selection on internode length and flowering date was consistent with the hypothesis of adaptive divergence in plasticity. Few costs or benefits of plasticity were detected independently from the expressed phenotype, so plasticity was selected primarily through selection on the phenotype. Correlations between phenotypes and their plasticity varied with the environment and would cause indirect selection on plasticity to be environment dependent. We showed that an appropriate plastic response even to a rare environment can greatly increase genotypic fitness when that environment is favorable. Selection on the measured characters contributed to local adaptation and fully accounted for fitness differences between populations in all treatments except the woodland site at natural density.

Editor: A. Caballero

Kathleen Donohue, Dinan Messiqua, Elizabeth Hammond Pyle, M. Shane Heschel, and Johanna Schmitt "EVIDENCE OF ADAPTIVE DIVERGENCE IN PLASTICITY: DENSITY- AND SITE-DEPENDENT SELECTION ON SHADE-AVOIDANCE RESPONSES IN IMPATIENS CAPENSIS," Evolution 54(6), 1956-1968, (1 December 2000). https://doi.org/10.1554/0014-3820(2000)054[1956:EOADIP]2.0.CO;2
Received: 21 October 1999; Accepted: 1 June 2000; Published: 1 December 2000
JOURNAL ARTICLE
13 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top