German scientists have uncovered the secret to the attractiveness of a woman's gait. They filmed women's silhouettes to ensure that body details didn't distract from their movements, and then asked men which women they found more attractive.
Most men chose women who swayed their hips while walking. It turns out that this smooth, dancing gait is typical for women during the period when conception is most likely. Movement while walking or dancing is a powerful signal of fertility, which men perceive subconsciously.