A 100-million-year dragon killer
Komodo dragons are one of the largest living species of lizards, growing to a length of up to 3 meters and weighing around 70 kilograms. They're living on several central Indonesian islands for more than 100 million years. Why are they still alive? According to an international team of researchers, it's because Komodo dragons have space-age skulls. They've discovered that the giant lizard 'uses a combination of 60 razor-sharp serrated teeth, powerful neck muscles and what researchers are calling a 'space-frame"' skull to butcher prey with awesome efficiency.' The researchers used finite element analysis (FEA) software 'to test the bite force and feeding mechanics of the predator.' But read more...
You can see on the left an image showing the killing teeth of the 100 million-year-old Komodo dragon, also known as Varanus komodoensis. (Credit: University of New South Wales (UNSW) on this page) As said the researchers on another page, "the skull of the Komodo dragon is optimised to resist biting and pulling forces simultaneously and localised differences in bone composition can greatly influence the distribution of stress throughout the entire structure."
This research project has been led by Dr Stephen Wroe of the School of Biological, Earth and Environmental Sciences (BEES) at UNSW, with the help of paleontologist Karen Moreno.
These two researchers were joined by Philip Clausen and Colin McHenry of the University of Newcastle, New South Wales, Australia to develop the Computational Biomechanics Research Group (CBRG) at UNSW.
By the way, you can find more information about the Komodo dragon via Wikipedia.
You can see of the left another image of an analysis of a Komodo dragon's head (Credit: CBRG at UNSW).
Now, let's go back to the UNSW news release to learn more about Komodo dragons' skulls. "Unlike most modern predators, Varanus komodoensis applies minimal input from the jaw muscles when killing and butchering prey. But it compensates using a series of actions controlled by its postcranial muscles. A particularly interesting feature of the skull's performance is that it reveals considerably lower overall stress when these additional forces driven by the neck are added to those of the jaw-closing muscles. This remarkable reduction in stress in response to additional force is facilitated partly by the shape of the bones, but also by the way bone of different strengths are arranged within the skull."
Karen Moreno provides additional details in this documeny written for a BEES seminar, "Inside the Komodo dragon's head: A story about form, function and behaviour using computational modelling." "The Komodo dragon (Varanus komodoensis) has been the subject of much scientific interest, not only because of its fearsome reputation as a predator (it is one of very few large reptiles to take prey as large as itself), but also because of its conservation status as an endangered species and recent discovery of parthenogenic reproduction. Here, in the first detailed functional analysis of the Komodo dragon's remarkable killing and butchering techniques, we demonstrate the presence of mechanical traits that appear to be unique among modern reptiles, but were probably common in extinct species such as carnivorous dinosaurs and sabre toothed cats. Analyses were based on anatomical dissection, in vivo bite force, pull-gauge and observational data, together with newly-developed 3-D computer-modelling techniques."
This research paper has been accepted on APril 1, 2008 by the Blackwell's Journal of Anatomy on April 1, 2008 if I don't make a mistake, because the paper is not onmline yet. The title of the article, when published, should be "Cranial performance in the Komodo dragon (Varanus komodoensis) as revealed by high-resolution 3-D finite element analysis."
Sources: University of New South Wales, Sydney, Australia (UNSW) news release, April 15, 2008; and various websites
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