DOI: 10.5061/dryad.fn2z34v1w
title: Acclimation capacity of critical thermal maximum varies among populations: Consequences for estimates of vulnerability

description: Adaptive plasticity in thermal tolerance traits may buffer organisms
 against changing temperatures, making such responses of particular
 interest in the face of global climate change. Although population
 variation is integral to the evolvability of this trait, many studies
 inferring proxies of physiological vulnerability from thermal tolerance
 traits extrapolate data from one or few populations to represent the
 species. Estimates of physiological vulnerability can be further
 complicated by methodological effects associated with experimental design.
 We evaluated how populations varied in their acclimation capacity (i.e.,
 the magnitude of plasticity) for critical thermal maximum (CTmax) in two
 species of tailed frogs (Ascaphidae), cold-stream specialists. We used the
 estimates of acclimation capacity to infer physiological vulnerability to
 future warming. We performed CTmax experiments on tadpoles from 14
 populations using a fully factorial experimental design of two holding
 temperatures (8℃, 15℃) and two experimental starting temperatures (8℃,
 15℃). This design allowed us to investigate the acute effects of
 transferring organisms from one holding temperature to a different
 experimental starting temperature, as well as fully acclimated responses
 by using the same holding and starting temperature. We found that most
 populations exhibited beneficial acclimation, where CTmax was higher in
 tadpoles held at a warmer temperature, but populations varied markedly in
 magnitude of the response and the inferred physiological vulnerability to
 future warming. We also found that the response of transferring organisms
 to different starting temperatures varied substantially among populations,
 although accounting for acute effects did not greatly alter estimates of
 physiological vulnerability at the species-level or for most populations.
 These results underscore the importance of sampling widely among
 populations when inferring physiological vulnerability, as population
 variation in acclimation capacity and thermal sensitivity may be critical
 when assessing vulnerability to future warming. 
description: # Acclimation capacity of critical thermal maximum varies among
 populations: Consequences for estimates of vulnerability *** There are six
 datasets associated with this study. They each have their own README
 files. Please see each individual file's README for more information.
 **Note** that empty cells in all data files denote missing data. Missing
 data are explained in the associated manuscript. ## Description of the
 data and file structure Six datasets: 1. Acclimation\_Experiments -
 individual level CTmax data using ramping experiments for different
 starting and holding temperatures 2. Buffering\_Metrics - population level
 environmental and physiological buffering data 3.
 lmmbothspecies\_withcolor - population level CTmax estimates for both
 species from linear mixed models with colors (used for plotting) 4.
 datlmmmon\_color - population-level data derived from the plasticity
 linear mixed model for Ascaphus montanus (used for plotting) 5.
 datlmmtruei\_color - population-level data derived from the plasticity
 linear mixed model for Ascaphus truei (used for plotting Figure 4) 6.
 emmeanpop\_wide - Population level estimates of plasticity in wide format,
 as estimated from species-specific models ## Sharing/Access information
 Correspondence: Amanda Cicchino, Department of Biology, Colorado State
 University, Fort Collins, CO 80521, USA; Email:
 cicchino@rams.colostate.edu; ORCID: 0000-0003-0170-829X ## Code/Software
 Code for data analysis and figure creation for this manuscript is included
 as a separate [Rmd] file through Dryad.