Researchers Hiroto Tanaka and Isao Shimoyama (of Harvard University and University of Tokyo) have constructed a tiny replica of the swallowtail butterfly. The crudely made model uses just balsa wood, rubber bands, and a steel wire crank. The goal is to better understand the biomechanics of butterfly flight.
"Butterfly flight is somewhat mysterious because it's roughly the opposite of 'as the crow flies.' Butterflies flit about rather than flying in a straight line. That actually costs them more energy, Dudley said, so scientists assume their looping flying serves some evolutionary purpose.
'The advantage is that it's thought to be an anti-predator behavior,' Dudley said. 'The claim is that irregular flight paths are a permanent signal of prey unprofitability.'
Would-be predators presumably take one look at the chaotic, loopy butterfly flight and decide to go after easier to predict snacks.
The Japanese researchers somewhat capture this oscillating type of flight with their plastic-winged flyer, but Dudley argued that the differences between the bot and a real butterfly are so great as to invalidate the biological lessons the researchers try to draw..." (Read more).