Rhoetosaurus brownei and foot posture in sauropod dinosaurs

11 April 2019
  • Sauropod dinosaurs include the largest animals to ever walk the earth. In recent decades, new discoveries have helped paint a better picture of how they lived, but many aspects of their palaeobiology remain unclear. Here, we quantify how they may have kept their hind feet on the ground.
  • Using various conventional and computational methods, we assessed the range of motion in the digits of the hind foot of Rhoetosaurus brownei, a Jurassic sauropod from Australia, to establish a gamut of potential foot postures. With additional input of biomechanical principles we ultimately delimit these to a predictable in-life posture.
  • We found that the foot exhibited greater flexibility than previously thought. The hindfoot of Rhoetosaurus brownei was determined to be ‘skeletally digitigrade’, implying the animal walked with its toes in a ‘high-heeled’ fashion. However, the posture was almost certainly ‘functionally plantigrade’, meaning the animal actually impressed the full bottom surface of its foot on the ground, by virtue of an inferred cushioning pad.
  • The soft tissue pad beneath the elevated part of the foot appears to be a key biomechanical innovation in sauropods that evolved during the Early to Middle Jurassic. The acquisition of this trait in sauropod evolution probably facilitated the trend towards gigantic body size.

Media contact: Andréas Jannel, a.jannel@uq.edu.au  +61 (0) 452 113 904

Jannel, A., Nair, J.P., Panagiotopoulou, O., Romilio, A. and Salisbury, S.W. 2019. "Keep your feet on the ground": simulated range of motion and hind foot posture of the Middle Jurassic sauropod Rhoetosaurus brownei and its implications for sauropod biology. Journal of Morphology. 2019. 1–30 PDF