The Functional and Allometric Implications of Hipbone Trabecular Microarchitecture in a Sample of Eutherian and Metatherian Mammals

Abstract The pelvis plays an active role in weight bearing and countering the ground reaction forces incurred by hindlimbs thus making it a critical component of locomotor skeleton. Accordingly, this anatomical region is theoretically ideal for inferring behavior from both external skeletal morphology trabecular microarchitecture, with latter possibly offering nuanced insights into mechanical loading environment given its increased plasticity higher turnover rate. However, microarchitecture also known to be influenced variety factors including body size, sex, age, genetic regulation, diet activity level, that collectively hinder ability generate consistent functional inferences. In study, comparative sample mammals (42 species spanning four orders) varying sizes, yet comparable repertoires, were evaluated determine effects phylogeny locomotion on hipbone microarchitecture. This study found weak signal detected differences bone volume fraction degree anisotropy across certain pre-assigned categories, while confirming previously recognized allometric scaling trends reported other mammalian samples based femur. Within primates, more anisotropic pattern was observed quadrupedal attributed their repetitive regimes stereotypical limb excursions, isotropic values revealed taxa utilizing varied arboreal repertoires. Humans, despite frequent predictable associated use bipedalism, showed relatively values. highlights confounding influence consequently limit utility as method investigating adaptation.