THE huge carnivorous Komodo dragon isn't just the largest living lizard, it also packs the biggest poisonous punch of any creature.

What's more, new research shows that the mega-meat eater probably inherited its "biggest" and "most venomous" mantle from its extinct Australian ancestor, the 7m-long dragon, Megalania, The Australian reports.

Adult male Komodo dragons weigh in at about 100kg and exceed 3m in length. A typical meal weighs 30-40kg.
Deer are common prey. While humans seldom fall victim to Komodo dragons, earlier this year a dragon stalked a poacher for several days and then, with a companion, waited for the man, caught, killed and ate him.

"They're the cleverest of all lizards. They're very smart," said Melbourne University venom researcher Bryan Fry, head of the international team that reports on the lizard's weaponry today in the US journal Proceedings of the National Academy of Sciences
The biggest surprise of all is that until now researchers didn't even know the Komodo Dragon - a monitor lizard in a group called the Varanidae - was poisonous.

"Nobody looked," Dr Fry said.

That's because Komodo dragons lack the grooved-tooth venom delivery system found in other varanids.

Instead, Dr Fry's team found the lizard uses sharp, serrated teeth to open gaping wounds in its prey into which the venom easily flows.

The wounds naturally bleed profusely while compounds in the venom increase blood flow and reduce blood pressure, inducing shock in the victim.
They findings debunk a common belief the dragon's prey is killed by deadly bacteria in rotting food stuck in its mouth.

"Their teeth are shiny white and their gums pink.

"They are remarkably clean animals," said Dr Fry, who worked with captive Komodo dragon's in Singapore.

In the wild, Komodo dragons are highly endangered, living only on the Indonesian islands of Komodo, Rinca and Flores.

Dr Fry's colleague, biomechanist Stephen Wroe from the University of NSW, compared the anatomies of the dragon and the Megalania, which existed until roughly 40,000 years ago.

He concluded that both species wielded lightweight but sophisticated skull and tooth adaptations, which allowed them to kill large animals through rapid blood loss.

"Australia's Megalania was probably the largest venomous animal that ever lived," he said.