FEATURED STORY The Scaly Ones

hey climb walls and scuttle upside down across ceilings, dive to the ocean floor to feed on algae, even glide through the air from treetops. Some, with no limbs and extremely long tails, look like snakes; others are snakes. Many are nearly invisible in their home habitats; others announce their presence to their neighbors and warn off potential rivals by flashing colorful dewlaps, or fanlike structures, that lie just underneath their lower jaws [see photograph below]. They dine on everything from microscopic insects to hefty animals. Some wield lethal toxins through long, hollow fangs. They are members of the order Squamata, "the scaly ones," more popularly known as lizards and snakes. They are also one of the most successful orders of tetrapod (four-legged) vertebrates on Earth. In some people they provoke a phobic reaction (particularly the snakes). But we, among many others, find them irresistibly fascinating. Then again, our interest is also a professional one: we have devoted our careers to them.