Asymmetric toes aid underwater swimming
The unique morphology of the toes of the great crested grebe (Podiceps cristatus), which are asymmetrically lobed with a narrower skin flap on the lateral side of the toe, enables these birds to swim very efficiently. Here we study video recordings of a diving grebe and stroboscopic pictures of its moving feet and conclude that the bird uses a hydrodynamically lift-based foot (power) stroke to pro