Fig. 4. Independent contrast analysis of evolutionary change in relative melon area
and evolutionary change in sexual dimorphism in body length for 21 species of
cetacean. Positive values on the y-axis represent the evolution of an
increase in the lateral projected area of the melon relative to the lateral
projected area of the rest of the body. Negative values on the y-axis
represent the evolution of a decrease in the lateral projected relative area
of the melon. Positive values on the x-axis represent the evolution
of longer males relative to females and negative values represent the
evolution of shorter males relative to females. This result shows that species
that have evolved relatively larger males tend also to have evolved relatively
larger melons.
