Featured Research

from universities, journals, and other organizations

Komodo Dragons Even More Deadly Than Thought: Combined Tooth-venom Arsenal Key To Hunting Strategy

Date:
May 19, 2009
Source:
University of Melbourne
Summary:
The effectiveness of the Komodo dragon bite is a combination of highly specialized serrated teeth and venom, a new study shows. The authors also dismiss the widely accepted theory that prey die from septicemia caused by toxic bacteria living in the dragon's mouth.

Komodo dragons are the largest lizards in the world.
Credit: iStockphoto/Anna Yu

A new study has shown that the effectiveness of the Komodo Dragon bite is a combination of highly specialized serrated teeth and venom. The authors also dismiss the widely accepted theory that prey die from septicemia caused by toxic bacteria living in the dragon's mouth.

Using sophisticated medical imaging techniques, an international team led by Dr Bryan Fry from the University of Melbourne have revealed that the Komodo Dragon (Varanus komodoensis) has the most complex venom glands yet described for any reptile, and that its close extinct relative Megalania was the largest venomous animal to have lived.

The work will be published in the next issue of the journal Proceedings of the National Academy of Sciences.

"These large carnivorous reptiles are known to bite prey and release them, leaving the prey to bleed to death from the horrific wounds inflicted. We have now shown that it is the combined arsenal of the Komodo Dragon's tooth and venom that account for their hunting prowess," said Dr Fry from the Department of Biochemistry and Molecular Biology, Bio21 Institute at the University of Melbourne.

"The combination of this specialized bite and venom seem to minimise the Dragon's contact with its prey and this allows it to take large animals."

Komodo Dragons are native to the islands of Indonesia, with adult males weighing over 100kg, and exceeding 3 metres in length. They have around 60 highly serrated teeth which are frequently replaced during their lifetime.

The researchers conducted a comprehensive study of the Komodo Dragon bite, employing computer techniques to analyze stress in a dragon's jaws and compare them to those of a crocodile. The dragons were found to have much weaker bites than crocodiles, but magnetic resonance imaging (MRI) of a preserved dragon head revealed complex venom glands and specialised serrated teeth which create deep lacerations for entry of the venom.

"We believe that the dragon is able to weaken and immobilize their prey with a venomous bite that increases the damage done by their long serrated teeth," said Dr Fry.

The researchers located and surgically excised the glands from a terminally ill dragon at the Singapore Zoo, and used mass spectrometry to obtain a profile of the venom molecules. The team also analysed which toxin genes were expressed in the dragon's venom gland.

The effects of venom were also tested by the team and found to be similar to that of the gila monster and many snakes which cause a severe loss in blood pressure by widening blood vessels, thereby inducing shock in a victim. These findings may explain the observations by Dr Fry and others that Komodo Dragon prey become still and unusually quiet soon after being bitten. Bitten prey also bleed profusely, consistent with the team's discovery that the venom was also rich in toxins that prolong bleeding.

The researchers also examined fossils of the Dragon's giant extinct relative Megalania (Varanus priscus). From similarities in skull anatomy they determined that this seven metre lizard would have used a similar venom and bite system, making it the largest venomous animal to have ever lived.


Story Source:

The above story is based on materials provided by University of Melbourne. Note: Materials may be edited for content and length.


Journal Reference:

  1. Fry et al. A central role for venom in predation by Varanus komodoensis (Komodo Dragon) and the extinct giant Varanus (Megalania) priscus. Proceedings of the National Academy of Sciences, 2009; DOI: 10.1073/pnas.0810883106

Cite This Page:

University of Melbourne. "Komodo Dragons Even More Deadly Than Thought: Combined Tooth-venom Arsenal Key To Hunting Strategy." ScienceDaily. ScienceDaily, 19 May 2009. <www.sciencedaily.com/releases/2009/05/090518172650.htm>.
University of Melbourne. (2009, May 19). Komodo Dragons Even More Deadly Than Thought: Combined Tooth-venom Arsenal Key To Hunting Strategy. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2009/05/090518172650.htm
University of Melbourne. "Komodo Dragons Even More Deadly Than Thought: Combined Tooth-venom Arsenal Key To Hunting Strategy." ScienceDaily. www.sciencedaily.com/releases/2009/05/090518172650.htm (accessed April 18, 2014).

Share This



More Plants & Animals News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Vermont Goat Meat Gives Refugees Taste of Home

Vermont Goat Meat Gives Refugees Taste of Home

AP (Apr. 18, 2014) Dairy farmers and ethnic groups in Vermont are both benefiting from a unique collaborative effort that's feeding a growing need for fresh and affordable goat meat. (April 18) Video provided by AP
Powered by NewsLook.com
The Great British Farmland Boom

The Great British Farmland Boom

Reuters - Business Video Online (Apr. 17, 2014) Britain's troubled Co-operative Group is preparing to cash in on nearly 18,000 acres of farmland in one of the biggest UK land sales in decades. As Ivor Bennett reports, the market timing couldn't be better, with farmland prices soaring over 270 percent in the last 10 years. Video provided by Reuters
Powered by NewsLook.com
Flamingo Frenzy Ahead of Zoo Construction

Flamingo Frenzy Ahead of Zoo Construction

AP (Apr. 17, 2014) With plenty of honking, flapping, and fluttering, more than three dozen Caribbean flamingos at Zoo Miami were rounded up today as the iconic exhibit was closed for renovations. (April 17) Video provided by AP
Powered by NewsLook.com
Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins