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First published online November 17, 2006
Journal of Experimental Biology 209, 4607-4621 (2006)
Published by The Company of Biologists 2006
doi: 10.1242/jeb.02539

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Jumping performance of froghopper insects

Malcolm Burrows

Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK

View larger version (53K): [in a new window]   Fig. 1. Drawing of the anterior part of Philaenus, viewed from the side, to show the orientation of the proximal parts of its three pairs of legs. Each leg is shown in its most anterior position (black) and in its most posterior position (grey). The pivots of the coxae with the thorax are indicated by black dots and vertical arrows. The plane of movement is not orthogonal to the plane of the drawing.

View larger version (125K): [in a new window]   Fig. 2. Sequential images of a jump by Philaenus captured at 7500 s-1 and with an exposure time for each of 0.05 ms. The images are arranged vertically in two columns and are timed from the image at take-off (0 ms). The first movements of the right hind leg (white arrow) occurred 1.04 ms before take-off.

View larger version (30K): [in a new window]   Fig. 3. Graphs of leg and body movements during a jump by Philaenus captured at 8000 s-1. (A) Five points on the body (see cartoon inset) are plotted against time. Take-off is indicated by the right arrow and vertical yellow bar. The first movement of a hind leg occurred 0.875 ms before take-off (left arrow and yellow bar). The tarsi of the front and middle legs left the ground 0.5 ms before take-off (middle arrow and yellow bar). Velocity, measured as the movement of the centre of an ellipse representing the overall shape of the body, is plotted as a two-point average of successive frames (blue line). (B) Sequential movements of the five points on the body as the insect moved through the field of view of the stationary camera, superimposed on an image of the froghopper in its starting position. The black arrowheads and the linking black lines show the position of these five points at take-off. The corresponding positions of these points at different times during the jump can be read frame-by-frame from these positions at take-off.

View larger version (73K): [in a new window]   Fig. 4. Jump by Aphrophora viewed ventrally and captured at 5000 s-1 with an exposure time of 0.05 ms. (A) Sequence of four images from the jump. (B) Drawings to show the joint positions of the hind legs before (-0.4 ms, fully levated) and after (0 ms, fully depressed) their rapid movements.

View larger version (43K): [in a new window]   Fig. 5. (A) Sequential images captured at 5000 s-1 and with an exposure of 0.05 ms of Philaenus jumping toward and to the right of the camera to show the leg movements. Movements of the right hind femur are indicated by the arrows. (B) Graphs of changes in the angle between the femur and the longitudinal axis of the body and of the femoro-tibial joint (see inset drawings) in a jump by another Philaenus captured at 4000 s-1. (C) Movements of four points on the body (see cartoon) and of the angular changes of the femur and tibia (coloured lines). The changes in the femoro-tibial angle at the times indicated (ms) are shown in detail on the right.

View larger version (44K): [in a new window]   Fig. 6. Hind leg movements of a restrained Aphrophora recorded simultaneously by a camera capturing images at 1000 s-1 and with an exposure of 0.25 ms and by a photoelectric device (see Materials and methods). (A) Two sequential images, the first showing the hind legs fully levated before the attempted jump and the second after the rapid movement. The inset drawings show the position of the hind legs in these two frames. Note the small piece of reflective tape on the hind femur. The outputs of the photoelectric device during six jumps were captured at a sampling rate of 45 kHz and low-pass filtered at 2 kHz. One trace in blue shows the unfiltered recording. The leg movements were complete in 0.3 ms. (B) Seven attempted jumps by a second Aphrophora show that the movement was again complete in 0.3 ms.

View larger version (83K): [in a new window]   Fig. 7. Images from two jumps by Neophilaenus captured at 2000 s-1 with an exposure of 0.25 s. (A) A jump in which the take-off occurred within 1 ms of the first movements of the hind legs: body angle, 36°; take-off angle, 55°; take-off velocity, 4.2m s-1. (B) A jump toward and to the right of the camera in which the body was raised by the front and middle legs to assume a higher take-off angle: body angle, 50°; take-off angle, 72°; take-off velocity, 4.0 m s-1; body mass, 3.2 mg.

View larger version (37K): [in a new window]   Fig. 8. Jump by Cercopis. (A) Sequential frames from the jump viewed from the side and captured at 2000 s-1 with an exposure of 0.25 ms. (B) Graph of the movements of six points on the body (see cartoon inset) during this jump. (C) Sequential movements of the same six points superimposed on an image of Cercopis in its starting position to show their vertical and horizontal displacement. The yellow arrows show the direction of the initial movements of the femoro-tibial joint. Body angle at take-off, 16°; take-off angle, 45°; take-off velocity, 3.8m s-1; body mass, 41.9 mg.

View larger version (36K): [in a new window]   Fig. 9. Jump by Lepyronia. (A) Two columns of sequential images from a jump captured at 4000 s-1 and with an exposure of 0.25 ms. At the start, the body was raised at an angle of 61° to the ground so that only the tips of the tarsi of the front and middle legs were in contact with the ground. (B) Movements of five points on the body (see image in C) against time. (C) Movements of the same body points to show their vertical and horizontal displacement. The black curved arrows show the direction of the initial movements of the femoro-tibial joint. Body angle at take-off, 61°; take-off angle, 90°; take-off velocity, 4.0 m s-1; body mass, 17 mg; temperature, 36°C.

View larger version (23K): [in a new window]   Fig. 10. (A) Trajectories of five jumps by the same Philaenus. Take-off angles are the average over the first 10 ms after take-off. (B) Rotation of the body during a single jump by Philaenus. A fixed point on the head in the vertical or in the horizontal plane was plotted against time. The body spins about its longitudinal (y axis) and transverse (x) axis undergoing five cycles of rotation in the first 70 ms that it is airborne. Images were captured at 1000 s-1; body mass, 12 mg.

View larger version (84K): [in a new window]   Fig. 11. A jump in which Aphrophora flapped its wings after take-off. The selected images captured at 1000 s-1 and with an exposure of 0.25 ms are arranged in two columns. At take-off (time 0 ms) the wings were not opened. 5 ms later it started to lose height and 8 ms after take-off opened its hind wings and flapped them.

View larger version (51K): [in a new window]   Fig. 12. Contribution of the hind legs of Philaenus in walking. Images were captured at 1000 s-1 with an exposure of 0.5 ms. Selected images, viewed ventrally, are shown at the times indicated. (A) Horizontal walking. The middle and front legs were lifted in a sequence to perform a swing phase of similar duration (thick black bars) and contact the ground during a stance phase of variable duration (thin blue bars). The hind legs did not move. (B) Vertical walking in which the hind legs did contribute.