Here’s one I’ve been dying to post. How does a fox catch mice when they’re hiding under the snow? Foxes have sharp hearing, so they obviously listen for the little tunnelers. Pouncing in a random direction, though, is only successful about one out of five tries (18%). But, pouncing in a northerly direction is effective three out of four times (73%)! While the mechanism is yet to be worked out, the researchers think there must be some magnetism involved. Pretty cool.
The NPR link above has a general description, plus the cool drawings. Ed Yong originally covered this in 2011 and has the more technical description.