Thermal niche estimators and the capability of poor dispersal species to cope with climate change.

David Sánchez-Fernández,Alexandra Cieslak,Valeria Rizzo,Arnaud Faille,Ignacio Ribera,Javier Fresneda

doi:10.1038/srep23381

Abstract

For management strategies in the context of global warming, accurate predictions of species response are mandatory. However, to date most predictions are based on niche (bioclimatic) models that usually overlook biotic interactions, behavioral adjustments or adaptive evolution, and assume that species can disperse freely without constraints. The deep subterranean environment minimises these uncertainties, as it is simple, homogeneous and with constant environmental conditions. It is thus an ideal model system to study the effect of global change in species with poor dispersal capabilities. We assess the potential fate of a lineage of troglobitic beetles under global change predictions using different approaches to estimate their thermal niche: bioclimatic models, rates of thermal niche change estimated from a molecular phylogeny, and data from physiological studies. Using bioclimatic models, at most 60% of the species were predicted to have suitable conditions in 2080. Considering the rates of thermal niche change did not improve this prediction. However, physiological data suggest that subterranean species have a broad thermal tolerance, allowing them to stand temperatures never experienced through their evolutionary history. These results stress the need of experimental approaches to assess the capability of poor dispersal species to cope with temperatures outside those they currently experience.

Highlights

Bioclimatic models showed that suitable temperatures during the Last Glacial Maximum (LGM) were estimated to occur in karst areas separated from their current ranges by non-suitable habitat patches, that is, by areas without deep subterranean environment
When we considered the estimated LGM paleotemperatures of the areas currently occupied by the species, the maximum rate of thermal niche change was found in a population of Trapezodirus orobios, from 4.4 °C to 10.4 °C in the 21,000 years since the estimation used for the LGM (i.e., 0.029 °C/100 years)
When we predicted the fate of the studied subterranean species under a global change scenario using their current distribution to estimate their thermal niche, results were dramatic

Summary

Introduction

There is, one assumption that these species clearly violate, as they have a limited capacity for dispersal[20] They cannot be expected to occupy much of their suitable habitat at short time scales due to their reduced mobility, so their only possibility to cope with fast climate change is to persist in situ. We consider the estimated thermal niche from experimentally determined thermal tolerances data We compare these results with the predicted climatic conditions in 2080 for the same areas and discus the suitability of all these approaches to estimate thermal niche and the capability of poor dispersal species to cope with climate change

Objectives

Methods

Results

Conclusion