Dog owners can sleep easy tonight because physicists have discovered how rapidly a wet dog should oscillate its body to dry its fur. Presumably, dogs already know. From the article: "Today we have an answer thanks to the pioneering work of Andrew Dickerson at the Georgia Institute of Technology in Atlanta and a few buddies. But more than that, their work generates an interesting new conundrum about the nature of shaken fur dynamics. Dickerson and co filmed a number of dogs shaking their fur and used the images to measure the period of oscillation of the dogs' skin. For a labrador retriever, this turns out to be 4.3 Hz."