Goannas: Giant Lizards with a Venomous Bite

Goanna's gigantic venomous ancestor, megalania prisca, would slash open struggling giant kangaroos and emus with their lethal bite, until they collapsed and bled to death. These were some leaping lizards, twenty-three feet long and weighing in over 1000 pounds!

Goannas are giant monitor lizards whose other family members include Komodo dragons. Researchers have discovered the lizards are more closely related to snakes than previously thought. Scientists have also determined goannas produce a similar venom to snakes. The benefit of such research is the discovery could aid the development of new medicines based on lizard toxins.

In the past, because these enormous lizards feed on dead carcasses, toxic bacteria in their mouth was blamed as the culprit for the pain, swelling, and profuse bleeding suffered from goanna bites. A researcher noticed after witnessing a bite from a Komodo dragon that symptoms developed rapidly. Doctors were alerted because bacteria doesn't work fast enough to cause instant painful complications.

On closer examination, scientists studying goannas, the closest living relative of the Komodo dragon, found a huge gland running down the side of the lizard's jaw. After squeezing the gland, venom was released and pooled at the base of the goanna's teeth. If, you wonder why we are just learning about this, I imagine no one wanted to get close enough to these monsters before. Goannas raise up on two feet when threatened and stick out their tongue like snakes and two-year olds.

Researchers have identified nine types of toxins from lizard venom which snakes have in common. Doctors still claim there is no reason for humans to be afraid of goannas, because the venom produced isn't in large enough amounts to cause 'serious harm'. Sorry, that is not a strong enough disclaimer for me. Goannas do lack fangs, so they aren't able to inject venom into their prey like snakes. But, they do have teeth.

Research suggests venom in reptiles evolved only once, about 200 million years ago, in a common ancestor shared by snakes and lizards. When the species split- one walked away, and the other slithered. One scientist working with the goannas stated, "They are beautiful animals". Take a look at their photograph. It gives credence to the report that came out recently about the high rate of drug use in the science field.

Fear of snakes is one of the most common phobias in the world, except at some rural church services. I've seen grown men squeal like girls at the sight of a harmless garden snake. In their defense, it was announced in 2005, there are NO non-venomous snakes with the exception of constrictors. A recent study shows that this is a learned behavior mankind developed overtime for survival. Psychologists found children and adults detect images of snakes and spiders quicker among an array of other animals which were in fact more dangerous.

The study continues on goannas and their venomous bite. The good news for us is the venom has already been found to have a dramatic effect on dropping blood pressure and preventing blood clots in humans. Hopefully, this wasn't due to the victim's massive blood loss!

www.theage.com.au/news/national/goannas-no-lounge-lizards/2005/11/19/1132017026262.html