A, Moderate SSD - male resting on female (Herennia multipuncta). B, Extreme SSD - male walking over female (Nephila pilipes). C, Female mean body size increases monotonically sevenfold, but male size oscillates within a threefold range (SSD in parentheses; we arbitrarily define extreme SSD with females more than five times male size). Red underlined values significantly exceed Monte Carlo simulated size ranges. Gray denotes unknown males. Female and male size evolution are independent (n = 26; r² = 0.055; p = 0.787).