which creatures keep their ears protected from water (e.g. crocodile)?
According to the San Diego Zoo, crocodiles “have slits on their heads that lead to a well-developed inner ear, and the slits close up when they dive to keep water out” (http://www.sandiegozoo.org/animalbytes/t-crocodile.html) Research has found that Penguins and some turtles have “venous structure in the form of a corpus cavernosum (CC) in their middle ear (ME) submucosa. The CC may be viewed as a special organelle that can change ME volume for pressure equilibration during deep-sea diving it is a pressure regulating organelle (PRO). A similar CC and muscles also surround the external ear (EE) and may constrict it, isolating the tympanic membrane from the outside.