Allometric Scaling in the Molars of Titi Monkeys

Abstract

Titi monkeys (Callicebus) have large intra-generic variations in cranial size and molar morphology. Cranial and dental measurements were taken on 29 titi monkeys. The data were transformed to natural logarithms. 1000 bootstrap samples were randomly drawn with replacement, and the regressions were computed for each sample based on the major axis and reduced major axis (e. g., Sokal & Rohlf, 1995) to determine the allometric relationship between the cranial length and molar area within titi monkeys. The molar area showed positive allometry against the cranial length, because the lower limits of the 95% confidence intervals of the allometric coefficients for both the reduced major axis and major axis were above the isometric value.