The world’s oceans are home to a wide variety of rays; over 500 different species spanning 13 families to be exact. With their cartilaginous bodies, rays are close cousins of the shark. They do differ, however, in their body shape, number of gill slits, and ways in which they swim and breathe. A ray’s tail is generally very long and skinny, and in many species equipped with a sharp, venomous barb which they use as their main line of defense. This makes it very important for divers who may be shore diving in areas containing stingrays to do the “stingray shuffle” when entering the water: they simply shuffle their feet along the bottom so as to gently push a stingray out of the way instead of stepping right on top of it.