Cover image: Pictured is a snapshot of a dog lapping water, showing the backward curl of the dog's tongue and the column of water drawn up when the tongue retracts. Sean Gart et al. constructed a physical model of tongue–water interactions that occur when dogs drink. The model showed that dogs time their bite to coincide with the moment when the water column pinches off from the tongue, thus maximizing the water intake per bite. The model also suggests that curling the tongue might increase the size of the water column by increasing the surface area of the tongue in contact with the water. See the article by Gart et al. on pages 15798–15802. Image courtesy of John J. Socha, Sean Gart, and Sunghwan Jung.