Fig. 2: Forest plots of overall effect sizes.

a Trait means, expressed as log-response ratios (lnRR) between competition and control groups. b Trait variation, expressed as log-coefficients of variation ratio (lnCVR). Effect sizes are showen as mean ± 95% confidence intervals (CIs). K denotes the number of effect-size estimates. Statistical significance was assessed using a random-effects meta-regression model and two-sided Tukey post hoc post hoc comparisons. Statistical details are provided in Supplementary Data 2. * P < 0.05, ** P < 0.01, *** P < 0.001.