Caterpillars have a unique “two-body” system of movement that may have implications for robotics and human biomechanics, U.S. researchers say.
The scientists found that the gut of the crawling hawkmoth caterpillar moves forward independently of and in advance of the surrounding body wall and legs, instead of moving with them. This is the first time this type of movement has been reported in an animal, the study authors noted.
“Understanding this novel motion system may help efforts to design soft-bodied robots. It may also prompt re-examination of the potential role soft tissues play in biomechanical performance of humans and other animals,” study senior author Barry Trimmer, a professor of biology and of natural sciences at Tufts University, said in a university news release.
The findings are published online July 22 in the journal Current Biology.
“Although internal tissue movement caused by locomotion has been identified in many organisms, the caterpillars seemed to be propelling themselves by means of a two-body system — the body wall container and the gut it contained. This may contribute to the extraordinary freedom of movement seen in these soft-bodied crawlers,” first author Michael Simon said in the news release.
Further research is needed to determine if this type of movement offers caterpillars an evolutionary advantage, and how this finding may prove valuable in robotics, added Simon, who conducted the study as part of his doctoral research in Trimmer’s lab.
“The focus to date has been on robots’ external design, but we also have to look at how it’s most advantageous to arrange the inside of the robot and any payload. Would motion be enhanced, for example, by packing more mass toward the rear, as these caterpillars seem to do?”
A grant from the U.S. National Science Foundation funded the research.