When it comes to getting airborne, most insects rely on elastic energy stored in their limbs to hurl themselves aloft. Chris Elliott from the University of York, UK, explains that locusts and fleas store a huge amount of elastic energy ready for takeoff, thanks to the neurotransmitter octopamine,which increases the strength of the muscular twitch that powers the insect's explosive leap. So when he heard about a Drosophila mutant that could jump, despite lacking octopamine, Elliott was puzzled. Somehow these insects could still take off, even though they couldn't synthesize octopamine. Was octopamine essential for boosting their launch(p. 3515)?
Elliott and his collaborator John Sparrow began testing the jumping forces of wild-type and octopamine-deficient flies, and found that the wild-type flies could jump over a distance of at least 28.5 mm, generating a peak force of 274 μN. But the octopamine-deficient flies seemed to have some problems. They could still jump, but only managed a 20 mm range, generating half the force of the natural fly populations.
The team suspects that tiny Drosophila do not need to store the enormous amounts of energy that locusts use to become airborne, as the octopamine-deficient flies were still capable of getting aloft. But a little bit of octopamine-powered thrust at the right moment certainly helps.