Patterns-of-plasticity

Code to support publication "Patterns of phenotypic plasticity along a thermal gradient differ by trait type in an alpine plant"

This repository contains R code for analyses conducted and figures produced for a forthcoming publication in Functional Ecology that examined the response of 14 traits to a high-resolution thermal gradient in an alpine plant, from seed germination to flower production.

• Please note that the R code is currently available as a single long Rmarkdown script (Patterns of plasticity Rmarkdown file) to demonstrate the structure of the data analyses conducted and figures in the manuscript. It may not be entirely functional standalone as-is. I have included additional data files from whcih it should be possible to run the code within the Rmarkdown but saved large model outputs and an html markdown are not up at this stage (will aim to add at a later date).

Abstract

1. Climate change presents many challenges for plants, a major one of which is the steady increase in the temperatures that plants are exposed to during germination, growth, and reproduction. Generating a more complete understanding of the capacity for plants to respond and of the role that phenotypic plasticity plays ¬in facilitating species’ responses to warming temperatures is a central objective in global change ecology.
2. Different traits expressed across life stages might be expected to exhibit a variety of responses to temperature due to phenotypic plasticity and genetic variation, even within a species. However, the extent of the variation among trait types and the relative contribution of plasticity and genetics to responses along a thermal gradient are not well understood. Here we studied an alpine plant, Wahlenbergia ceracea, to determine the shapes of response curves in 14 germination, leaf, physiology, and reproductive fitness traits across a broad thermal gradient of 12 temperatures while also comparing responses among family lines.
3. Trait types differed markedly: germination, leaf, and reproductive traits showed non-linear plasticity with best performance at intermediate temperatures, whereas physiology traits were generally less responsive to temperature. Variation in plasticity among families was lowest for the traits most necessary for tolerating environmental extremes (e.g. heat tolerance), suggesting that physiology traits may be canalised and fitness suffers for it. In contrast, variation in means, and plasticity in some cases, among families in germination traits suggests genetic variation and hence the potential to respond to selection.
4. Our results illustrate the variety of responses that may occur in response to temperature, and the frequent occurrence of complex non-linear plastic responses that would not have been apparent with comparison of fewer temperatures. We discuss the physiological, ecological, and evolutionary insights our findings provide into the response of wild species to the changing climate.