Ontogenetic shift in response to prey-derived chemical cues in prairie rattlesnakes Crotalus viridis viridis  

作　　者：Anthony J. SAVIOLA David CHISZAR Stephen E MACKESSY 

机构地区：[1]School of Biological Sciences, University of Northern Colorado, 501 20th Street, CB 92, Greeley, CO 80639 USA [2]Department of Psychology, CB 345, University of Colorado, Boulder, Colorado 80309 USA

出　　处：《Current Zoology》2012年第4期549-555,共7页动物学报（英文版）

摘　　要：Snakes often have specialized diets that undergo a shift from one prey type to another depending on the life stage of the snake. Crotalus viridis viridis （prairie rattlesnake） takes different prey at different life stages, and neonates typically prey on ectotherms, while adults feed almost entirely on small endotherms. We hypothesized that elevated rates of tongue flicking to chemical stimuli should correlate with particular prey consumed, and that this response shifts from one prey type to another as in- dividuals age. To examine if an ontogenetic shift in response to chemical cues occurred, we recorded the rate of tongue flicking for 25 neonate, 20 subadult, and 20 adult （average SVL = 280.9, 552, 789.5 mm, respectively） wild-caught C. v. viridis to chemi- cal stimuli presented on a cotton-tipped applicator; water-soluble cues from two ectotherms （prairie lizard, Sceloporus undulatus, and house gecko, Hemidactylusfrenatus）, two endotherms （deer mouse, Peromyscus maniculatus and lab mouse, Mus musculus）, and water controls were used. Neonates tongue flicked significantly more to chemical cues of their common prey, S. undulatus, than to all other chemical cues; however, the response to this lizard＇s chemical cues decreased in adult rattlesnakes. Subadults tongue flicked with a higher rate of tongue flicking to both S. undulatus and P. maniculatus than to all other treatments, and adults tongue flicked significantly more to P. maniculatus than to all other chemical cues. In addition, all three sub-classes demonstrated a greater response for natural prey chemical cues over chemical stimuli of prey not encountered in the wild （M. musculus and H. frenatus）. This shift in chemosensory response correlated with the previously described ontogenetic shifts in C. v. viridis diet. Be-cause many vipers show a similar ontogenetic shift in diet and venom composition, we suggest that this shift in prey cue dis- crimination is likely a general phenomenon among viperid snakes.

关 键 词：Gape-limited predator Prey choice Trophic adaptation Vomeronasal chemoreception 

分 类 号：Q959.223.5[生物学—动物学] S667.904.1[农业科学—果树学]