The ontogeny of grasshopper jumping performance
1991
Queathem, E.
This study describes how jumping ability changes through ontogeny in the grasshopper Schistocerca americana (Acrididae: Cyrtacanthacridinae).Grasshoppers must moult to increase in size, and their ability to jump fluctuates greatlythrough ontogeny, resembling a series of parabolas that increase in height with each moult. Jumpenergy and maximal jump distance increase similarly with size, but jump energy peakslater within an instar. Mass-specific jumping ability, or the distance an animal can jump per unit massof animal, drops off rapidly over time both within and between instars. Males and females gothrough the same number of instars, but females are substantially larger. Adult femalesundergo fluctuations in jumping ability as they produce and oviposit clutches, while male jumpingability rises to a plateau and levels off. Mechanistic explanations for these changes in jumpingability are proposed. These patterns should have profound implications for the evolution ofsuch life history traits as age at first reproduction, size at maturity, and clutch size byaffecting body size-related trade-offs between mortality and fecundity.
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