Relationship between the calcaneal size and body mass in primates and land mammals

The relationship between calcaneal size and body mass in extant primates and other land mammals is examined using regression analyses to provide simple equations for estimating the body mass of extinct primate and land mammal species based on the calcaneus. The results imply that among the linear calcaneal dimensions, the calcaneal width at the talar articular surfaces (CA2) is likely the best body mass estimator for land mammals (including primates), and the width of the posterior talar articular surface (CA3) appears to be relatively good body mass estimator for primates. The equation with a 95% prediction interval for estimating the body mass (BM, in g) using CA2 (in mm) for land mammals is: BM = exp(2.928 × ln CA2 + 0.981 ± 0.772) × 1.076; the corresponding equation using CA3 (in mm) for primates is: BM = exp(2.555 × ln CA3 + 3.536 ± 0.641) × 1.067.