Estimations of body shape and three-dimensional digital reconstructions of representative archosaurs along the ancestral bird line support hypotheses of a gradual, stepwise acquisition of more-crouched limb postures across much of theropod evolution but indicate that an accelerated change, rather than a discrete transition from more-upright postures, occurred within the clade Maniraptora (birds and their closest relatives, such as deinonychosaurs).
- Vivian Allen
- Karl T. Bates
- John R. Hutchinson
