Extended Data Fig. 1: Distribution of SSD within tetrapod clades.
Boxplots showing the distributions of SSD in each order of mammals (n = 1,633 species and 23 orders) and birds (n = 4,098 species and 34 orders) and family of squamates (n = 3,136 species and 41 families) and amphibians (n = 2,369 species and 48 families). The red dashed line represents SSD of 0, and the blue dotted lines represent the cut-off between monomorphic and dimorphic species, at 10% difference in size (absolute SSD value ~ 0.09). Boxplot are coloured according to the median SSD value in each clade – red for male-biased, blue for female-biased, and white for monomorphic. Boxplots are centred on the median value of each group, with the top and bottom bounds of the box representing the 75th and 25th percentiles, respectively, and the top and bottom whiskers representing the maximum and minimum values within 1.5 times the interquartile range, respectively. Icons from PhyloPic.org under a CC0 1.0 license: Panthera leo, Margot Michaud; Turdus pillaris, Sharon Wegner-Larsen; Varanus komodoensis, Steven Traver; Hyla versicolor, Will Booker.
