Percentege of bird and mammal populations that show different temporal responses in body size, taking into account <i>(a)</i> only the sign of the changes (upper panels), and <i>(b)</i> the statistical significance of the changes (lower panels).

<p>Data were analyzed separately for trend and significance because statistical significance depends on sample size (which varies from case to case), and also because some studies only report the sign of the temporal trend, while other studies only report that changes were not significant (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183051#pone.0183051.s002" target="_blank">S1 Dataset</a> for details).</p

Climate change and body size trends in aquatic and terrestrial endotherms: Does habitat matter?

<div><p>Several studies have claimed that reduction in body size comprises a nearly universal response to global warming; however, doubts about the validity of this pattern for endothermic species have been raised recently. Accordingly, we assessed temporal changes in body mass for 27 bird and 17 mammal species, to evaluate if a reduction in body size during the 20^th century is a widespread phenomenon among endothermic vertebrates. In addition, we tested if there are differences in the temporal change in size between birds and mammals, aquatic and terrestrial species, and the first and second half of the 20^th century. Overall, six species increased their body mass, 21 species showed no significant changes in size, and 17 species decreased their body mass during the 20th century. Temporal changes in body mass were similar for birds and mammals, but strongly differ between aquatic and terrestrial species: while most of the aquatic species increased or did not change in body mass, most terrestrial species decreased in size. In addition, we found that, at least in terrestrial birds, the mean value of the correlation between body mass and year of collection differs between the first half and the second half of the 20^th century, being close to zero for the former period but negative for the later one. To our knowledge, this is the first study showing that temporal changes in body mass differ between aquatic and terrestrial species in both mammals and birds.</p></div

Climate change and body size trends in aquatic and terrestrial endotherms: Does habitat matter? - Table 1

<p>Posterior means (X), lower and upper confidence intervals (L95%CI and U95%CI, respectively), and Markov chain Monte Carlo p-value (pMCMC) obtained by phylogenetic generalized linear mixed models, with body mass as dependent variable, year of collection as the independent variable, species as a random factor, taxonomic group (class) and habitat as fixed factors, and (absolute) latitude, longitude, sex and length of the time series as covariates (model A). An interaction term between the year of collection and taxonomic group (class) or habitat was included in model B and C, respectively. For each model, the Deviance Information Criterion (DIC) score is provided in brackets; and for each factor, the level that was not dropped into the intercept is given in brackets.</p

Naya_et_al_DataSets

Basal metabolic rate, together with geographic coordinates and climatic data, for 458 mammal species (or sub-species

Correlation coefficient between body size and year of collection for <i>(a)</i> the four species groups that were compared, and <i>(b)</i> all the species included in the analysis.

<p>Aq Birds: aquatic birds, Ter Birds: terrestrial birds, AqMamm: aquatic mammals, Ter Mamm: terrestrial mammals. N = number of species in each group. Bars: 95% confidence intervals. * denotes P < 0.05 and § denotes P < 0.1.</p

<i>(a)</i> Change in land surface temperature for the last century (modified from [29]), and <i>(b)</i> correlation coefficient between body size and year of collection for terrestrial bird species during the first (before 1950) and second (after 1950) half of the 20^th century.

<p>* denotes P < 0.05 and § denotes P < 0.1.</p

Posterior means (X), lower and upper confidence intervals (L95%CI and U95%CI, respectively), and Markov chain Monte Carlo p-value (pMCMC) obtained by phylogenetic generalized linear mixed models including data before 1950, after 1950, and comparing both periods of time.

<p>For the factor “sex”, the level that was not dropped into the intercept is provided in brackets.</p

TableS3

Data on basal metabolic rate and intestinal length for 30 rodent species

TableS1

Data on basal metabolic rate, body mass, and geographic, climatic and ecological variables for 195 rodent species

TableS2

Parameter estimation (and standard deviation) for models including exogenous factors in addition to body mass