Journal ArticleControl of high-speed jumps in muscle and spring actuated systems: a comparative study of take-off energetics in bush-crickets (Mecopoda elongata) and locusts (Schistocerca gregaria)Goode, Chloe K; Woodrow, Charlie; Harrison, Shannon L; Deeming, D Charles; Sutton, Gregory P<title>Abstract</title> <p>The Orthoptera are a diverse insect order well known for their locomotive capabilities. To jump, the bush-cricket uses a muscle actuated (MA) system in which leg extension is actuated by contraction of the femoral muscles of the hind legs. In comparison, the locust uses a latch mediated spring actuated (LaMSA) system, in which leg extension is actuated by the recoil of spring-like structure in the femur. The aim of this study was to describe the jumping kinematics of<italic>Mecopoda elongata</italic>(Tettigoniidae) and compare this to existing data in<italic>Schistocerca gregaria</italic>(Acrididae), to determine differences in control of rotation during take-off between similarly sized MA and LaMSA jumpers. 269 jumps from 67 individuals of<italic>M. elongata</italic>with masses from 0.014 g to 3.01 g were recorded with a high-speed camera setup. In<italic>M. elongata</italic>, linear velocity increased with mass^0.18and the angular velocity (pitch) decreased with mass^−0.13. In<italic>S. gregaria</italic>, linear velocity is constant and angular velocity decreases with mass^−0.24. Despite these differences in velocity scaling, the ratio of translational kinetic energy to rotational kinetic energy was similar for both species. On average, the energy distribution of<italic>M. elongata</italic>was distributed 98.8% to translational kinetic energy and 1.2% to rotational kinetic energy, whilst in<italic>S. gregaria</italic>it is 98.7% and 1.3%, respectively. This energy distribution was independent of size for both species. Despite having two different jump actuation mechanisms, the ratio of translational and rotational kinetic energy formed during take-off is fixed across these distantly related orthopterans.</p>Springer2023-12-0110510851Journal of Comparative Physiology B1936597 to 6050174-1578https://doi.org/10.1007/s00360-023-01524-22015317National Science Foundation