Wednesday, October 31, 2012

Happy Halloween readers! In honour of the occasion, we're going to tell you a story about fire ants and phorid flies.

Fire ants are very aggressive insects, armed with powerful stings that can kill frogs, lizards and even people. But when alarmed they release a pheromone, attracting a female phorid fly - the last thing any fire ant will want to do. The fly injects her eggs through a needle-like
appendage into the ant's thorax. A newly-hatched maggot makes its way into the ant's head, making itself at home by eating the brain. When the maggot is nearly ready to leave, it directs the "zombie" ant to go somewhere away from other ants (preferably a moist and leafy place). The unfortunate ant is decapitated by chemicals that break down membranes, and the maggot finishes off any remaining food in the head before emerging.

Looking at the photo, some of you may have noticed what looked like mandibles either side of the fly - and that's exactly what they are. This is the end of the process as the fly breaks free of the decapitated head.

Due to being accidentally imported in the 1930s, fire ants have become a big problem for organisms in the southern US. But over recent years scientists have been importing phorid flies to cope with the problem. According to Dr. Sanford Porter (US Department of Agriculture), 6 species of phorid flies have been released and 2 are spreading with the ants. Efforts have been relatively successful at controlling fire ant populations and the flies do not have a taste for native ants, reducing further impact on biodiversity. On a last interesting note, the flies do not make a great numerical impact on ant populations - but the ants are so afraid of them, they become reluctant to collect food. We don't think anyone can blame them!

Photo credit: Sanford D. Porter, USA.

http://www.bbc.co.uk/nature/19970460

http://news.nationalgeographic.com/news/2009/05/photogalleries/zombie-ants/index.html#/zombie-ants-phorid-flies-approach_4287_600x450.jpg
Happy Halloween readers! In honour of the occasion, we're going to tell you a story about fire ants and phorid flies. 

Fire ants are very aggressive insects, armed with powerful stings that can kill frogs, lizards and even people. But when alarmed they release a pheromone, attracting a female phorid fly - the last thing any fire ant will want to do. The fly injects her eggs through a needle-like appendage into the ant's thorax. A newly-hatched maggot makes its way into the ant's head, making itself at home by eating the brain. When the maggot is nearly ready to leave, it directs the "zombie" ant to go somewhere away from other ants (preferably a moist and leafy place). The unfortunate ant is decapitated by chemicals that break down membranes, and the maggot finishes off any remaining food in the head before emerging.

Looking at the photo, some of you may have noticed what looked like mandibles either side of the fly - and that's exactly what they are. This is the end of the process as the fly breaks free of the decapitated head.

Due to being accidentally imported in the 1930s, fire ants have become a big problem for organisms in the southern US. But over recent years scientists have been importing phorid flies to cope with the problem. According to Dr. Sanford Porter (US Department of Agriculture), 6 species of phorid flies have been released and 2 are spreading with the ants. Efforts have been relatively successful at controlling fire ant populations and the flies do not have a taste for native ants, reducing further impact on biodiversity. On a last interesting note, the flies do not make a great numerical impact on ant populations - but the ants are so afraid of them, they become reluctant to collect food. We don't think anyone can blame them!

Photo credit: Sanford D. Porter, USA.

http://www.bbc.co.uk/nature/19970460

http://news.nationalgeographic.com/news/2009/05/photogalleries/zombie-ants/index.html#/zombie-ants-phorid-flies-approach_4287_600x450.jpg

No comments:

Post a Comment