A study published in the Journal of Chemical Ecology reports on nine species of Bruneian ants, whose workers "are known to have hypertrophied mandibular glands and release their glandular contents suicidally from the head by rupturing the inter- segmental membrane of the gaster." In other words, their heads explode. Exploding ants will instinctively commit suicide when their colony is attacked, killing not only themselves but often their attackers as well.
Sources:
Jones, T.H., D. A. Clark, A. A. Edwards, D. W. Davidson, T. F. Spande and R. R. Snelling. The Chemistry of Exploding Ants, Camponotus SPP. (Cylindricus COMPLEX). Journal of Chemical Ecology 30, 8 (2004).

I'd like to get a few of these to put in an ant farm with the regular ants. Just to see what would happen.
Regular Ant: Hey! This is our farm and if you don't get the hell out we're....
Bruneian Ant: Ka-boom!
Other Regular Ants: Yeah. Okay then. Welcome to our farm. We have cable and there's beer in the fridge. Hep your own selfs.
Posted by: Ana | April 25, 2005 at 09:17 PM
It reminds me of the Blazing Saddles scene when Cleavon Little puts a gun to his own head and takes himself hostage.
Posted by: gail | April 25, 2005 at 10:44 PM
There are so many movies that I need to see again now that I'd find the humor mmmmm, well, now that I'd just find the humor.
Posted by: Ana | April 26, 2005 at 06:18 AM
is their anyway possible you can get me live footage of this phenomena in action. I'm a research scientost amd I would love to post this on my developing web page. I UNDERSTAND work is work and if you want cash for this recording if you can get it that wont be a problem.
thank you very much
Curtis Threats
Posted by: Curtis Threats | June 28, 2006 at 10:44 PM
So obviously these are muslim ants.
Posted by: CraigC | August 26, 2006 at 10:37 AM
LMAO at "So obviously these are muslim ants". LOL, HA HA HA HA HA, ROFL...
Posted by: some guy | February 28, 2007 at 06:20 AM
wowowowo
Posted by: | April 12, 2007 at 06:46 AM
ummm...do these ants ever blow their sexual partner up if they're having an affair with them?
Posted by: BJ | April 17, 2007 at 08:43 AM
you...are...strange-minded
Posted by: | April 18, 2007 at 08:53 AM