How do caterpillars crawl? We might imagine them as a gooey tube inching forward in waves, but a research group at Tufts has found that their bodies behave in a more complex way, which they term 'visceral-locomotory pistoning', where the elastic gut of the caterpillar stretches and moves independently of the body wall. In order to peer inside the caterpillar's body, they used X-ray synchotron radiation, but later found a much easier way - using newly-hatched caterpillars, which are small and translucent to visible light. The biomechanics of soft-bodied animals is an inherently challenging subject. Modeling the physics is difficult because there are no rigid elements (skeletons, shells, and the like); it is also a challenge to find suitable reference points to track during motion.
Check out the fascinating video abstract freely available on the Current Biology website.
(Via New York Times)