Wednesday, May 18, 2011
Tuesday, May 17, 2011
by Stephen Messenger, Porto Alegre, Brazil on 05. 9.11
Travel & Nature
The daily life of a hardworking carpenter ant must be pretty repetitive, what with the constant marching and relentless leaf-cutting -- unless they run across a fungus which has the power to turn them into mindless, bumbling 'zombies', in which case, things can get interesting. Researchers from Penn State studying ants in Thailand have stumbled upon one of the spookiest parasitic phenomena ever recorded: a fungus that doesn't just kill its insect host -- it invades their minds and forces them to do its bidding.
This strange new fungus, Ophiocordyceps unilateralis, is a nasty parasite indeed, transforming its host ant's typical 'go-with-the-flow' attitude into one that's a bit less orderly. Infected ants have been observed deviating from their peers in line, seeming to lose direction as the growing fungus seizes control of their basic motor ability.
Once the fungus has reached the ant's head, it causes the insect to clamp-down on the underside of a leaf which locks in place as its jaw becomes dislocated -- subjecting the ant to a painful, self-inflicted death.
A few days later, the fungus forms a spore-rich structure from the dead ant's brain where it awaits its next unsuspecting victim.
David Hughes, one of the Penn State University researchers involved in the study, explains the phenomena to News.com:
The fungus attacks the ants on two fronts. Firstly by using the ant as a walking food source, and secondly by damaging muscle and the ant's central nervous system, resulting in zombie walking and the death bite, which place the ant in the cool damp understorey.
Together these provide the perfect environment for fungal growth and reproduction.
Recently, a similar parasite was found to be infecting several ant species in Brazil, but until now the physical process behind the phenomena had yet to be fully understood.