News in Science

Dragonflies can stay camouflaged during flight

Male dragonflies have mastered the art of camouflaging themselves even as they are moving, Australian researchers have discovered.

The study, published in today's issue of the journal Nature, found that the dragonfly achieves motion camouflage by adjusting its position in order to always occupy the same spot in its prey's retina - so it looks stationary while it is actually moving.

"Deployment of this sophisticated technique by the oldest airborne predator tricks the victim's retina into perceiving the stalker as stationary even while it darts about in pursuit," said Dr Aikiko Mizutani of the Australian National University in Canberra, who led the study.

Mizutani and his team used cameras that can pinpoint an object's position in three dimensions to reconstruct dragonfly movement.

"We reconstructed 15 three-dimensional flight trajectories of interactions between ... dragonflies, of which six showed clear evidence of active motion camouflage," Mizutani wrote.

The trick involves very precise flight control and positional sensing, and the scientists said they still weren't sure how the dragonflies manage it.