Figure 1.

Military dog practicing the “hup” position or standing on its hind legs while forelimbs are resting on a door or vehicle for balance. The ability to perform this task was rated as “excellent” if the dog could remain in position for 8 or more seconds, “good” if holding position for 5–7 s, “fair” if able to hold position for 1–4 s and “poor” if unable to hold for 1 s or less or unable to perform the position (10). Photograph courtesy of The U.S. Army [Public domain], via Wikimedia Commons.