A matter of taste
Vision and hearing are not paramount in the life of a Komodo dragon. Its eyes pick up moving objects but are less sensitive to inanimate details, and its ears detect only a limited range of sounds. But its sense of smell is phenomenal. Unlike mammals, the dragon relies on two specialised olfactory or nasal chambers, called Jacobson's organs, located in the roof of its mouth. It uses its forked tongue to flick out and trap chemical particles. Once redrawn, the tongue transfers these particles to the Jacobson's organs, and messages are sent from there via nerves to the brain. Its extraordinary ability to detect odours in this way enables the Komodo dragon to smell prey or carrion more than a kilometre away.
Komodo Island is one of the driest regions in Indonesia, with less than 600mm of rain a year. Monitor lizards such as Komodo dragons do not sweat; they can only pant to lower their body temperature and lay still in the shade or inside burrows. The dragons feel quite comfortable in water (they are actually pretty good swimmers). On really hot days, the few pools remaining from the very short rainy season are highly valued, providing relief from the scorching sun.
Up for it
Males adopt a series of defensive postures when they encounter rivals. They try to appear as large as possible by flattening their bodies from side to side and extending pouches by their throats; they also hiss and bend their tails sideways ready to give a strong lash to any opponents who gets too close. A contest is generally resolved by the rivals assessing each others' size and the smaller male backing off. But when two large males meet, they engage in ritualised combat, which may result in injury. Using their tails for support, they wrestle each other in an upright position, grabbing their opponents with their forelegs and trying to ground them.
BBC1 Dragons Alive (24 March) takes a fresh look at reptiles.
From an original article in the March 2004 issue of BBC Wildlife Magazine - Tracing the dragon