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Science

No Fairy Tale Dragon

by Randi Mrvos

Do you believe in dragons or are they the stuff of fairy tales? Let's take a trip to Komodo Island, northwest of Australia in the Indian Ocean. I've been told that dragons live there.

Using our binoculars, we focus at the edge of a wooded area. I see an animal that's about six to eight feet long. It's got scaly skin, a heavy head, a massive body, a powerful tail, and strong legs with large sharp clawed feet. Why it's no other than a komodo dragon, the largest lizard in world! I've heard that they can weigh almost 200 pounds. These giant lizards are found only on Komodo Island and on a few other islands in the country of Indonesia.

Komodo dragons have poor hearing. In dim light, they have trouble seeing well. But their sense of smell is keen. They can detect meat as far away as 2.5 miles (four km).

A komodo dragon gathers scent with its forked tongue. Then it pushes its tongue against a sensitive patch on the roof of the mouth called the Jacobson's organ. The Jacobson's organ helps the komodo dragon to recognize its prey by tasting its scent. The organ also indicates the location of the prey. If the prey scent is stronger on the right tongue tip, the komodo dragon knows that its next meal is approaching from the right.

Though they prefer decaying flesh, komodo dragons will ambush deer, wild pigs, monkeys, birds, and other reptiles. Komodo dragons were once thought to kill prey by infecting it with bacteria. As many as fifty species of bacteria grow in komodo dragon mouths. But when the bacteria were analyzed in a laboratory, they were found to be harmless. So the scientists looked closer.

By using MRI (magnetic resonance imaging), scientists scanned komodo dragon skulls. They discovered six venom glands on each side of the lower jaw. The venom was found to be as deadly as snake venom. At first, the venom glands had been overlooked because komodo dragon teeth are not hollow to deliver venom. Digging deeper, scientists learned that the venom is delivered through openings between the teeth.

A komodo dragon bite is weaker than a house cat's. So in order to have dinner, it bites and pulls, opening a wound for the venom to seep into. This method enables it to kill prey much larger than itself. Komodo dragons can eat up to their own weight in one sitting and then may not eat again for weeks.

But I'm not sure when this komodo dragon has last eaten. Is it my imagination or is it moving a bit closer? Has its forked tongue picked up our scent? Let's make a break for it. They can out run a human for a short distance. So pick up the pace. This is no fairy tale. You've seen for yourself—dragons really do exist.

The author wishes to thank Dr. Bryan Fry, Australian Research Council QEII Research Fellow, Venomics Research Laboratory, University of Melbourne for his expertise.

Bibliography

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Randi is a columnist for The Creativity Connection, an editor for the educational website www.Viatouch.com , and a former consultant for Pearson Digital Learning. She writes for children's, parenting, and writers' publications. Her publishing credits include Byline, Mothering, The Christian Science Monitor, Highlights for Children, Know, Nature Friend, and Learning through History Magazine.