What happens when fruit flies get aggressive?
12 Oct 2011 by Evoluted New Media
Hyper-aggressive fruit flies stand up on their hind legs and box with other flies says new research looking at hostility in the model organism.
The work – by researchers in American and Belgium – could one day lead to helping humans by providing a framework of how complex gene interactions affect behaviour.
Dr Trudy Mackay, professor of genetics at North Carolina State University, and her colleagues showed that mutations in a handful of genes made some passive fruit flies aggressive, and made some already aggressive fruit flies even more so.
Researchers measured aggression by watching flies for actions that include – from less aggressive to more aggressive: chasing other flies; puffing up their wings in a ‘wing threat’ position; kicking other flies; and standing on their back legs and boxing other flies with their front legs.
The work – published in Proceedings of the National Academy of Sciences – showed that certain portions of the fly brain, so called mushroom-bodies which affect locomotion, experience and memory, were smaller in hyper-aggressive flies. They also showed the effects of mating flies with different mutations to see which mutant combination had larger effects on aggression.
“This study shows that these brain networks are not simple, and that you can’t look at just one gene at a time,” said Dr Robert Anholt, study co-author.
The work also revealed that doses of lithium didn’t always calm the aggressive flies – some but not all were soothed by the mood-altering drug. Similar results were seen when the flies were given two other types of calming drug.
Complex genetic architecture of Drosophila aggressive behaviour
