Fig. 2: Heritability of heat tolerance.
From: Selective breeding enhances coral heat tolerance to marine heatwaves
Heritability is shown as parent-offspring regressions for (a) short- and (b) long-term heat stress exposures. Heat tolerance of offspring (F1) family mean in relation to the mid-parent value for short- (a) and long-term (b) heat stress exposures, based on each colonies ΔDHW50, the heat stress dosage at which the bleaching survival index BSI passes 0.5. The slope represents the narrow-sense heritability (h2) of heat tolerance shown as a posterior mean with 95% credible intervals calculated considering random intercepts for each cross. All data are standardised and shown as z scores, such that variance fully attributable to additive genetic effects (h2 = 1) would be represented by a 1:1 relationship (dashed line) between the parent and offspring heat tolerances. The narrow-sense heritability (h2) of short- and long-stress heat tolerance was 0.29 (±0.16 SE) and 0.23 (±0.16 SE), respectively, based on a frequentist animal model. This significant heritability is corroborated by the parent-offspring regressions presented here with higher but overlapping h2 estimates compared to the uncertainty of the animal model for short- and long-stress heat tolerance of 0.67 (95% credible interval: 0.34–0.98) and 0.52 (95% credible interval: 0.22–0.83), respectively. The predicted regression (bold line) and Bayesian 95% credible intervals (shading) are shown. Source data are provided as a Source Data file.
