Escape responses to three herbivorous gastropods to the predatory gastropod Conus textile.

Department of Zoology, University of Washington, Washington USA
Animal Behaviour (Impact Factor: 3.07). 01/1966; 14(2):340-5. DOI: 10.1016/S0003-3472(66)80094-5
Source: PubMed

ABSTRACT The herbivorous gastropods Strombus canarium, Lambis lambis, and Trochus pyramis evince escape responses, probably mediated by distance chemoreception, in the presence of the predatory gastropod Conus textile.In Strombus and Lambis, the response has two components: increase in the absolute rate of locomotion, and direction of locomotion away from the predator. When placed in the presence of C. textile, T. pyramis began moving, generally in the direction it faced.In control observations, a specimen of S. canarium moved at a mean rate of 2·7 mm/sec, by the leaping mode of locomotion characteristic of this and related genera. In the presence of C. textile, the rate increased to 6·8 mm/sec, due primarily to shortening of the lag or recovery period between leaps. In the presence of C. textile, a specimen of L. lambis moved at a rate of 11·9 mm/sec in the same manner as Strombus. In the presence of C. textile, a specimen of T. pyramis progressed at a rate of 1·9 mm/sec, by pedal locomotory waves.Comparison with absolute rates of locomotion by pedal locomotory waves in other marine gastropod molluscs leads to the conclusion that the leaping of Strombus and Lambis does not enable these gastropods to maintain a more rapid long-term rate of movement, but it confers a striking increase in agility, and a single leap provides an almost instantaneous increase in distance from a potential predator.

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