Video xray of a caterpillar on a treadmill

Biologists at Tufts University's School of Arts and Sciences studying crawling caterpillars have reported a unique "two-body" system of locomotion that has not previously been reported in any animal.

In an article published online July 22 in the journal Current Biology, the Tufts-led team reported that the gut of the crawling tobacco hawkmoth caterpillar (Manduca sexta) moves forward independently of and in advance of the surrounding body wall and legs, rather than moving along with them. Collaborating with Tufts were researchers from Virginia Tech and Argonne National Laboratory.

This informational video demonstrates the discovery, using synchrotron-sourced, phase-contrast, X-ray imaging to show how the gut is propelled forward in advance of the rest of the body during crawling.

I ran across some discussion of this research elsewhere today (lost the link); apparently it has some non-entomological implications re the design of robots. Other than that, it's interesting or not depending on whether you are interested in caterpillars.