Data from: Rensch's rule in large herbivorous mammals derived from metabolic scaling

Rensch’s rule, which states that the magnitude of sexual size dimorphism
tends to increase with increasing body size, has evolved independently in
three lineages of large herbivorous mammals: bovids (antelopes), cervids
(deer), and macropodids (kangaroos). This pattern can be explained by a
model that combines allometry, life-history theory, and energetics. The
key features are that female group size increases with increasing body
size and that males have evolved under sexual selection to grow large
enough to control these groups of females. The model predicts
relationships among body size and female group size, male and female age
at first breeding, death and growth rates, and energy allocation of males
to produce body mass and weapons. Model predictions are well supported by
data for these megaherbivores. The model suggests hypotheses for why some
other sexually dimorphic taxa, such as primates and pinnipeds (seals and
sea lions), do or do not conform to Rensh’s rule.