The role of edges in the selection of a jump target in Mantis religiosa

Publication Type:Journal Article
Year of Publication:2005
Authors:Hyden, K, Kral, K
Journal:Behavioural Processes
Start Page:122
Date Published:2005
Type of Article:Research
Keywords:Behaviour, image motion, Mantis religiosa, range determination, shape determination, visual target

Before jumping to a landing object, praying mantids determine the distance, using information abtained from retinal image motion resulting from horizontal peering movements. The present study investigates the peering-jump behaviour of Mantis religiosa larvae with regard to jump targets differing in shape and size. The experimental animals were presented with square, triangular and round target objects with visual extensions of 20 and 40deg. The cardboard objects, presented against a uniform white background, were solid black or shaded with a gradation from white to black. It was found that larger objects were preferred to smaller ones as jump targets, and that the square and triangle were preferred to the round disk. When two objects were presented, no preference was exhibited between square and triangular objects. However, when three objects were presented, the square was preferred. For targets with a visual angle of 40deg, the amplitude and velocity of the horizontal peering movements were greater for the round disk than for the square or triangle. This amplification of the peering movements suggests that weaker motion signals are generated in the case of curved edges. This may help to account for the preference for the square and triangle as jump targets.

Refereed Designation:Unknown
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith