One of the main question addressed by paleoanthropologists is the recovery of plausible motions for extinct species whose knowledge is generally limited to incomplete bones and skeletons. Calculating locomotion for extinct species is mainly based on the direct application of captured trajectories to numerically reconstructed skeletons. The gait is judged realistic compared to another if it minimizes energy and preserves balance. In computer animation, adapting a motion to a skeleton is addressed by so-called motion retargeting techniques. The goal is then to ensure that the resulting motion is close to the initial one while dealing with new bones’ dimensions. In this paper, we adapt methods used in computer animation in order to solve such a problem. This approach is based on a two-steps framework: first, a reference motion of the feet is warped in order to optimize a set of biomechanical general laws, such as energy and Jerk minimization. Second, the remaining degrees of freedom (d...