Some researchers believe that prey are killed by pathogenic bacteria in the dragons' mouths but the new research – published in the latest issue of Proceedings of the National Academy of Sciences – shows that the combination of the reptiles' teeth and venom likely accounts for their hunting prowess.
"The view that the Komodo routinely kills using dirty oral bacteria is wrong," says research co-author, Dr Stephen Wroe from the University of New South Wales, Australia. "The dragon is truly poisonous. It has modified salivary glands that deliver both hypertensive and anti-blood-clotting agents, which, in combination with lightweight but sophisticated cranial and dental adaptations, allows it to kill large animals through rapid blood loss."
The researchers used computer modeling to analyse the Komodo dragon bite and found that dragons have much weaker bites than crocodiles of a similar size. However, magnetic resonance imaging revealed the dragons have complex venom glands as well.
After surgically excising the glands from a terminally ill dragon in a zoo, the researchers used mass spectrometry to obtain a profile of the venom, finding that the toxin was similar to that of the Gila monster and many snakes. The venom causes a severe loss in blood pressure by preventing blood clotting and widening blood vessels, thus inducing shock in a victim.
The researchers also examined fossils of the giant extinct dragon relative Varanus megalania and determined that this seven-metre-long lizard was one of the largest venomous animals to have ever lived.
A member of the goanna family with ancestors dating back more than 100 million years, the Komodo dragon is the world's largest living lizard and inhabits the central Indonesian islands of Komodo, Rinca, Flores, Gili Motang and Gili Dasami. It grows to an average length of two to three metres and weighs around 70 kilograms. The reptile's unusual size is attributed to a phenomenon known as island gigantism, since there are no other carnivorous mammals to fill the niche on the islands where they live.
The lizards are apex predators and dominate the ecosystems in which they live. Although Komodo dragons eat carrion, they also hunt and ambush prey including invertebrates, birds, and mammals.
The dragon's large size and fearsome reputation has made it a popular zoo exhibit since Western scientists first brought it to world attention in 1910. In the wild its total population is estimated at 4,000 to 5,000. Its range has contracted due to human activities and it is listed as vulnerable by the International Union for Conservation of Nature.
Dr. Steve Wroe | EurekAlert!
Further reports about: > Komodo > Komodo dragon bite > Varanus komodoensis > Varanus megalania > anti-blood-clotting agents > blood vessel > carnivorous reptiles > cranial and dental adaptations > goanna family > magnetic resonance imaging > pathogenic bacteria > reptiles' teeth > seven-metre-long lizard
Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care
Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
17.11.2017 | Physics and Astronomy
17.11.2017 | Health and Medicine
17.11.2017 | Studies and Analyses