Jumping in springtails: mechanism and dynamics

Abstract

With 2 plates and 9 figures in the text) An analysis of the mechanism of the jumping organ of the cylindrical springtail Tomocerus longicornis and the globular springtail Dicyrtoma ornata is presented based on morphological examination and high-speed photography. Both species have a click mechanism involving deformation of the abdominal sclerites. Morphological and photographic evidence supports the hypothesis that eversion of the springing organ involves a hydroelastic mechanism based on haemocoel pressurization and increased tension in the abdominal sclerites. A computer model was used to analysejump kinematics and energetics. This model accounts for the spin observed during jumping and shows how body planform (e.g. cylindrical versus globular) and tail length can influence direction, height, range and rate of spin.

A miniature 7g jumping robot

“…Since there is no actuator capable of producing that much power at a weight of only a few grams, we decided to design a mechanisms which can be charged slowly, store the energy in a spring and release it on demand using a click mechanism. This mechanical principle is used by several small jumping animals, such as frogs [6], locusts [7], springtails [16], click beatles [4] and fleas [8].…”

The green leafhopper,Cicadella viridis(Hemiptera, Auchenorrhyncha, Cicadellidae), jumps with near-constant acceleration

“…During evolution they have refined many different escaping strategies (Cain, 1985;Masters and Eisner, 1990). One of the main methods used by insects to escape from predators is to increase the speed of locomotion (Bennet-Clark and Lucey, 1967;Evans, 1972;Christian, 1978;Brackenbury and Hunt, 1993;Maitland, 1992).…”

Jumping technique and climbing behaviour of the collembolan Ceratophysella sigillata (Collembola: Hypogastruridae)

“…From high speed cinematographic pictures (Christian, 1979;Brackenbury & Hunt, 1993) and the models by Brackenbury & Hunt (1993) it can be seen that animals with a long furca perfonn steep and often backward ori entated somersaults, but species with a short furca like the hypogastrurids show relatively low trajectories with a much slower rotation.…”