Fig. 1

Evolutionary history of parental care diversity in amphibians. a Distribution of parental care forms in amphibians (n = 1322 species; sample sizes for each care form in Supplementary Table 1a and Supplementary Fig. 1). The posterior distributions of the RJ Multistate transitions for the b rates of gain (q₀₁) and c rates of loss (q₁₀) of each care form are shown as box plots for comparison, and as posterior density plots for each care form alone. The central black dot in the box plots indicates the median, the box the upper and lower quartiles, the vertical lines the 95% credible intervals of the posterior distributions, and the filled dots beyond the lines indicate outlier estimates. Care forms are coded with the same colours across all panels. In b and c: EA egg attendance, EB egg brooding, TA tadpole attendance, TT tadpole transport, TB tadpole brooding, TF tadpole feeding, JA juvenile attendance, JT juvenile transport, V viviparity