Thursday, August 19, 2010

48mn-year old' Fossil Reveals History of Zombie Ants

Washington: Scientists have stumbled across a 48mn-year-old leaf fossil in Germany that depicts how a deadly fungus infected ants and turned them into zombies. Dr David P Hughes, from the University of Exeter and his colleagues made the discovery in Messel Pit, a site on the eastern side of the Rhine Rift Valley in Hesse, Germany. “This leaf shows clear signs of one well documented form of zombie-parasite, a fungus which infects ants and then manipulates their behaviour,” said Hughes.

The fungus, called Ophiocordyceps unilateralis, leads the ant to a leaf and when it reaches there, the ant goes into a ‘death grip’- biting down very hard on the major vein of a leaf. This means that when the ant dies, its body stays put so the fungus has time to grow and release its spores to infect other ants. The death grip bite leaves a very distinct scar on the leaves.

“This is, as far as we know, the oldest evidence of parasites manipulating the behaviour of their hosts and it shows this parasitic association with ants is relatively ancient and not a recent development,” Hughes said. “Hopefully we can now find more fossilised evidence of parasitic manipulation. This will help us shed further light on the origins of this association so we can get a better idea of how it has evolved and spread,” he added. Source ----- Image Source