Similarities and differences in the peering-jump behavior of three grasshopper species (Orthoptera: Caelifera)

Authors


Karl Kral, Institute of Zoology, Karl-Franzens-University Graz, A-8010 Graz, Austria. Tel: +43 (0) 316 380 5614; fax: +43 (0) 316 380 9875; email: karl.kral@uni-graz.at

Abstract

The peering-jump behavior was studied for the common field grasshopper Chorthippus brunneus, the meadow grasshopper C. parallelus and the alpine grasshopper Miramella alpina (Orthoptera, Caelifera). It was found that immediately before jumping M. alpina executes primarily unilateral object-related peering movements, with approximately twice the amplitude and velocity of the predominantly bilateral object-related peering movements of the other two species. Whereas M. alpina almost always jumped toward the black stripes in the experimental arena, the other species jumped toward both the black stripes and the white spaces between them. All three species preferred the same pattern of black stripes, which permitted them to view one black stripe frontally, with an additional black stripe to the left and right, in the lateral visual field. The similarities and differences in the peering-jump behavior of the three grasshopper species is discussed with regard to visual perception (parallax cues) and environmental adaptation.

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