RT Journal Article
SR Electronic
T1 Natural selection on plasticity of thermal traits in a highly seasonal environment
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 191825
DO 10.1101/191825
A1 Leonardo D. Bacigalupe
A1 Juan D. Gaitan-Espitia
A1 Aura M. Barria
A1 Avia Gonzalez-Mendez
A1 Manuel Ruiz-Aravena
A1 Mark Trinder
A1 Barry Sinervo
YR 2018
UL http://biorxiv.org/content/early/2018/03/19/191825.abstract
AB This preprint has been reviewed and recommended by Peer Community In Evolutionary Biology (http://dx.doi.org/10.24072/pci.evolbiol.100048). For ectothermic species with broad geographical distributions, latitudinal/altitudinal variation in environmental temperatures (averages and extremes) are expected to shape the evolution of physiological tolerances and the acclimation capacity (i.e., degree of phenotypic plasticity) of natural populations. This can create geographical gradients of selection in which environments with greater thermal variability (e.g., seasonality) tend to favour individuals that maximize performance across a broader range of temperatures compared to more stable environments. Although thermal acclimation capacity plays a fundamental role in this context, it is unknown whether natural selection targets this trait in natural populations. Here we addressed such an important gap in our knowledge by measuring survival, through mark recapture integrated into an information-theoretic approach, as a function of the plasticity of critical thermal limits for activity, behavioural thermal preference and the thermal sensitivity of metabolism in the northernmost population of the four-eyed frog Pleurodema thaul. Overall, our results indicate that thermal acclimation in this population is not being targeted by directional selection, although there might be signals of selection on individual traits. According to the most supported models, survival decreased in individuals with less tolerance to cold when cold-acclimated (probably because daily low extremes are frequent during the cooler periods of the year) and increased with body size. However, in both cases, the directional selection estimates were non-significant.