QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Young, B. A. Articles by Morain, M. Search for Related Content PubMed PubMed Citation Articles by Young, B. A. Articles by Morain, M.

The use of ground-borne vibrations for prey localization in the Saharan sand vipers (Cerastes)

Bruce A. Young^* and Malinda Morain

Department of Biology, Lafayette College, Easton, PA 18042, USA

View larger version (28K): [in a new window]   Fig. 1. Polar coordinate plots of the predatory strike of Cerastes cerastes. In each plot, the strike angle was measured between the long axis of the snake’s head and the midpoint of the prey’s body (with 0° defined as directly in front of the snake); distance (in cm) was measured from the tip of the snake’s snout to the midpoint of the prey. (A) Control strikes; (B) strikes following denervation of the olfactory and vomeronasal nerves; (C) strikes following denervation and bilateral occlusion of the eyes. Note the similarity between the control and denervated strikes and the marked decrease in distance and strike angle following occlusion of the eyes.

View larger version (21K): [in a new window]   Fig. 2. Distribution of strikes by angle. Significantly greater strike angles were recorded from control (black columns) and denervated (white columns) specimens than from the denervated specimens following visual occlusion (grey columns).

View larger version (15K): [in a new window]   Fig. 3. Accuracy of the strike following experimental manipulation. Bilateral strikes (in which both fangs contact the prey) were most common in the control (black columns) and denervated (white columns) trials, with decreasing levels of unilateral and missed strikes. Strikes recorded following denervation and visual occlusion (grey columns) showed reduced accuracy, with roughly equal numbers of bilateral, unilateral and missed strikes.

View larger version (32K): [in a new window]   Fig. 4. Response of the denervated and visually occluded specimens to artificial vibrational stimuli. Data are cumulative scores from 16 trials; each trial included 4 min of control and 30 s of each experimental condition. The strong response to the vibrational stimuli (including strikes in one-quarter of the trials) is evident in a comparison of the control (black column) and experimental data. The similar responses to isothermic targets (light grey columns) and those heated to mammalian body temperature (dark grey columns) suggest that the specimens were using vibrational, rather than thermal, cues.