Trait performance relationship between running speed (m s−1) and morphological traits estimated from mixed effects model with body size and body temperature as covariates. Shaded values are positive. Slopes significantly different from zero (at p < 0.05) are italicized and noted with ‘*’. Marginally significant effects (p < 0.1) are noted with ‘.’, and non-significant effects (p > 0.1) with ‘n.s.’. W, wood; C, concrete; M, metal.