Saturday, August 18, 2012

Speculative Fact regarding Beardie bites

 This was an interesting study that gives rise to thought..........but not to worry as the 'delivery system' for the venom has devolved and now only causes a slight irritation in some sensitive people..

Snakes and lizards share venom, evolutionary history, study finds

Nov. 16, 2005
Courtesy Nature and World Science staff

Conventional wisdom has it that, among reptiles, venom delivery is mainly associated with snakes, and that it underlies their dramatic evolutionary success: 2,500 out of 3,000 snake species are poisonous.

In contrast, venom delivery is found in just two lizard species, in which it is thought to have evolved independently from snakes.

But a new study by Bryan Fry of the University of Melbourne, Australia, and colleagues has found that that venom delivery among lizards may be much more widespread.

The researchers said they showed that members of two additional lizard lineages also produce and can deliver venom toxins. The lineages include Monitor Lizards and Eastern Bearded Dragons, a popular pet.

The new work suggests the side-effects of nasty lizard bites may actually be due to venom rather than incidental bacterial infection, as was previously thought, Fry and colleagues asserted.

Also, they said, the findings suggest snakes and lizards are much more closely related than has been previously believed. Snakes evolved from relatively advanced lizards, they suggested, rather than being a separate branch on the evolutionary tree.

The study is to be published online by the research journal Nature this week.

Among living reptile species, only the Gila Monster and Beaded Lizard were previously known to be poisonous, the researchers wrote. They claimed to have found toxins in four Monitor species and the Eastern Bearded Dragon.

A new genetic analysis shows that all lineages that can deliver toxins share a common ancestor, they claimed. This demonstrates “a single early origin of the venom system in lizards and snakes,” probably about 200 million years ago, they said, during the dinosaur era.

The research opens new avenues for drug development based on still unknown molecules found in lizard venom, they added.

“These molecules represent a tremendous hitherto unexplored resource not only for understanding reptile evolution but also for use in drug design and development,” they wrote. 

And, another article in concludes this:

Actually, according to the most recent research by Dr. Brian Fry of the University of Melbourne, bearded dragons are venomous. The researchers found venom similar to rattlesnake venom in bearded dragons. This is what they now believe causes the swelling when one is bitten by the lizard (they used to think that it was bacteria). Their delivery system is so primitive though that the venom is not really dangerous to humans except to cause pain and swelling.

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