Heres how you turn cockroaches into ‘zombie slaves’November 30th, 2007 - 2:23 pm ICT by admin
London, Nov 30 (ANI): Researchers have uncovered a neurological trick used by a species of wasp that live in tropical regions of India, Africa and the Pacific Islands, to turn cockroaches into ‘zombie slaves’.
The study, led by Frederic Libersat of Ben-Gurion University of the Negev in Israel, explains as to why, once stung, cockroaches can be led by a much smaller master towards certain death.
Researchers in the study have proven their theory by replicating the effect, and by using an antidote injection to release the cockroaches from their zombie state.
Zombie provide food to cockroach wasp (Ampulex compressa), for their hungry larvae.
The wasp relies on cockroaches for its grisly life cycle. But unlike many venomous predators, which paralyse their victims before eating them or dragging them back to their lair, the wasp’s sting leaves the cockroach able to walk, but unable to initiate its own movement.
The wasp then grabs the cockroach’s antenna and leads it back to the nest.
Libersat said that the cockroach walks like a dog on a leash and once home, the merciless wasp lays an egg on the docile cockroach’s belly, and the larva, once hatched, devours the hapless insect.
Libersat said that his team dont how exactly the wasps pull off the trick.
“We know the wasp injects a rich cocktail of toxins. But it was unclear how the venom could alter the victims’ behaviour so subtly, Nature quoted Libersat, as saying.
The researchers knew that the wasps tend to sting the cockroaches once to subdue them, then adminster another, more precise sting right into their victim’s brain. So they suspected that the venom might work by blocking a key chemical messenger.
The scientists report that the venom works to block a neurotransmitter called octopamine, which is involved in preparations to execute complex behaviours such as walking.
The team found that they could restore spontaneous walking behaviour in stung cockroaches by giving them a compound that reactivates octopamine receptors in the insects’ central nervous system. This, they conclude, means that the wasp venom probably blocks these receptors.
They also discovered that injecting unstung cockroaches with a compound that blocks these receptors produced a similar effect to that of the venom.
The study is published in the Journal of Experimental Biology. (ANI)
Tags: ben gurion, chemical messenger, cockroach, cockroaches, docile, larva, neurotransmitter, octopamine, rich cocktail, sting, tropical regions, university of the negev, venom, venomous, wasp, wasps, zombie slaves