Vietnamese jumping caterpillar discovery

This video says about itself:

Aug 20, 2013

Other caterpillar species are known to jump, but Cydia deshaisiana is the only one known to create a leaf shelter and hop around in it for three days, trying to escape the sun before settling for metamorphosis.

By Laura Poppick:

Jumping Caterpillar Hops Around In Leafy Cocoon For Protection From Sunlight (VIDEO)

08/21/2013 1:29 pm EDT

Hop over, Mexican jumping beans: Scientists have discovered another fascinating caterpillar species with impressive jumping skills.

During its larval stage, the moth Calindoea trifascialis crawls the dry forest floors of southern Vietnam amongst elephants and flying insects, spending most of its time chewing away at a protective, tent-like structure it makes out of leaf parts.

Eventually, when the caterpillar prepares to pupate and metamorphose into a moth, it rolls itself into a new type of protective leaf structure the thickness of a pinky finger, and then quivers itself onto the forest floor. It proceeds to hop around the forest floor within its leaf-roll for up to three days, directing itself away from sunlight.

Researchers with the University of Toronto and the Royal Ontario Museum discovered this behavior by chance during an undergraduate field course in Yok Don National Park in southern Vietnam. The finding surprised the researchers, as only a few other caterpillar species are known to hop, none within this type of leaf structure. The team reports their finding today (Aug. 20) in the journal Biology Letters. [Caterpillars Morph into Butterflies in Amazing 3D Images]

“The mechanics of it are pretty remarkable,” said Chris Darling, a biologist at the University of Toronto and an author of the paper, pointing out that the caterpillar’s movement resembles trying to hop inside a sleeping bag.

The team did not initially realize that the caterpillars were able to hop after collecting them from the forest floor. Instead, the researchers were simply interested in studying the caterpillars’ rolled structures, which they called “retreats”. The team stored several of these so-called caterpillar “retreaters” underneath their beds for further analysis, awaking later to the sound of rustling.

“We heard them in the middle of the night and wondered if it was a rat,” said Darling. “Lo and behold, it was the retreaters running around in the petri dish.”

The researchers collected more of these retreaters to try to figure out the purpose behind the behavior, and filmed 16 of them to observe the activity in detail. The scientists found that the caterpillars tended to direct themselves away from the sunlight, presumably to avoid drying up under the hot sun.

To determine how the caterpillars managed these impressive hops, the team created transparent, artificial retreats out of cellophane plastic, placed caterpillars inside and then sealed the containers shut to simulate a natural retreat.

The caterpillars took to the synthetic retreats as if they were their own, spinning silken mats on either end. The team, easily able to see through the clear structure, observed the caterpillars using the silken mats as springboards for their jumps, hooking their prolegs — protrusions that are not truly legs — to the mats, and then propelling themselves across to the other side of the retreat like a piston.

By laying mats on both sides of the retreat, the caterpillars were able to switch directions and maintain more control over their final resting places, where they would sit for up to 12 days until they emerged as moths.

Related articles

• Jumping caterpillar navigates by sun (bbc.co.uk)
• Vietnamese caterpillar hides inside leaf and hops blindly to escape sun (wired.co.uk)
• Move Over, Mexican Jumping Beans – There’s a New Jumping Caterpillar in Town (blogs.scientificamerican.com)
• Caterpillars, Moths & Butterflies (cheyfly.wordpress.com)
• Twig caterpillar on ivy (ivyguyzone6a.wordpress.com)
• Vietnam Caterpillar Constructs Leaf Shelters and Jumps in Them (sciencespacerobots.com)
• Jumping cocoons save lives (stuff.co.nz)
• Carnivorous caterpillars will eat you and everyone you love (grist.org)