The Komodo Dragon, the World's Largest Lizard

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The Komodo dragon (Varanus komodoensis) is the largest lizard, as opposed to reptile, on the face of the earth today, adults attaining lengths of six to 10 feet and weights approaching 150 pounds. Full-grown Komodo dragons are dull brown, dark grey, or reddish in color, while juveniles are green with yellow and black stripes. These lizards are the apex predators of their Indonesian island ecosystems; they occasionally capture live prey by hiding in vegetation and ambushing their victims, although they usually prefer to scavenge already-dead animals.

(In fact, the giant size of the Komodo dragon can be explained by its island ecosystem: like the long-extinct Dodo Bird, this lizard has no natural predators.)

Komodo dragons have good vision and adequate hearing, but rely mostly on their acute sense of smell to detect potential prey; these lizards are also equipped with long, yellow, deeply-forked tongues and sharp serrated teeth, and their rounded snouts, strong limbs and muscular tails also come in handy when targeting their dinners. (Not to mention when dealing with others of their own kind: when Komodo dragons encounter one another in the wild, the dominant individual, usually the largest male, prevails.) Hungry Komodo dragons have been known to run at speeds topping 10 miles per hour, at least for short stretches, making them some of the fastest lizards on the planet!

The Komodo dragon mating season spans the months of July and August.

In September, the females dig egg chambers, in which they lay clutches of up to 30 eggs. The mom-to-be covers her eggs with leaves and then lies over the nest to warm the eggs until they hatch, which requires an unusually long gestation period of seven or eight months. The newborn hatchlings are vulnerable to predation by birds, mammals, and even adult Komodo dragons; for this reason the young scamper up into trees, where an arboreal lifestyle provides them refuge from their natural enemies until they are large enough to defend themselves.

There has been some controversy about the presence of venom, or the lack of it, in the Komodo dragon's saliva. In 2005, researchers in Australia suggested that Komodo dragons (and other monitor lizards) have mildly venomous bites, which can result in swelling, shooting pains, and disruption of blood clotting, at least in human victims; however, this theory has yet to be widely accepted. There's also the possibility that the saliva of Komodo dragons transmits harmful bacteria, which would breed on the rotting bits of flesh wedged between this reptile's teeth. This wouldn't make the Komodo dragon anything special, though; for decades there has been speculation about the "septic bites" inflicted by meat-eating dinosaurs!

Classification of Komodo Dragons

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