FIGURE 7.

Dorsal views of speculative shoulder postures for Palorchestes. Long axes of the humerus and manus are indicated with black arrows. Schematic positions of the manus are shown at flexed (red) and extended (blue) positions when the elbow is rotated around the mean helical axis (dashed line). (a) In an adducted shoulder pose with the humerus held along the parasagittal axis as in large extant mammals, the skewed mean helical axis of the elbow causes lateral movement of the manus. (b) By abducting the shoulder, the mean helical axis is perpendicular to the body, and manus movement is aligned with the direction of travel. Actual manus position will also be affected by pronation/supination, scapular movements and soft tissues not considered here