As a dog owner, you want your best friend to be stress-free and relaxed, not rubbing his ears on the living room rug, shaking his head or pawing his ears to stop the itching. You know he is ...

Evolution is a master recycler. It often uses old structures (or ancient genes) for new jobs. The mammalian ear is a perfect example. Over the eons, the jawbones of our fish ancestors became three ...