Morphological Variability in Vipera palaestinae along an Environmental Gradient  

作　　者：Stanislav VOLYNCHIK 

机构地区：[1]National Collections of Natural History,Department of Zoology,Faculty of Life Sciences,Tel Aviv University Ramat Aviv 69978,Israel

出　　处：《Asian Herpetological Research》2012年第3期227-239,共13页亚洲两栖爬行动物研究（英文版）

摘　　要：The effect of local habitat conditions on organisms, including environmentally-induced morphological changes, constitutes an important aspect of macroecology and evolution. The degree of geographic intraspecific variation in body dimensions, corporeal ratios and scalation pattern among male and female Palestine vipers(Vipera palaestinae) in Israel were examined. Univariate and multivariate analyses using 20 variable features relating to metric and meristic characters were applied in order to determine the existence of geographic variability in this species. Univariate analysis revealed that the majority of morphological characters possess relatively minor interregional distinctions, with only a few traits demonstrating significant differences. Discriminant analysis of mixed-gender samples using a combination of variables did not distinguish between geographic groups within each sex. The multifactor approach slightly differentiated between samples when sexes were compared separately, but with much overlap. The continuous sampling method revealed no statistically significant relationship between geographic and metric variables across the distribution range. A weak latitudinal cline was observed in snout-vent length, with both sexes being larger in the south. Noticeable temperature-correlated intraspecific variability was found in both body and tail scale counts but not in head scalation features. Generally, both males and females demonstrate the same phenotype-environment correlation. The spatial variations in external morphology suggest that temperature conditions during early ontogenesis may induce quantitative changes in the scalation pattern of V. palaestinae.The effect of local habitat conditions on organisms, including environmentally-induced morphological changes, constitutes an important aspect of macroecology and evolution. The degree of geographic intraspecific variation in body dimensions, corporeal ratios and scalation pattern among male and female Palestine vipers(Vipera palaestinae) in Israel were examined. Univariate and multivariate analyses using 20 variable features relating to metric and meristic characters were applied in order to determine the existence of geographic variability in this species. Univariate analysis revealed that the majority of morphological characters possess relatively minor interregional distinctions, with only a few traits demonstrating significant differences. Discriminant analysis of mixed-gender samples using a combination of variables did not distinguish between geographic groups within each sex. The multifactor approach slightly differentiated between samples when sexes were compared separately, but with much overlap. The continuous sampling method revealed no statistically significant relationship between geographic and metric variables across the distribution range. A weak latitudinal cline was observed in snout-vent length, with both sexes being larger in the south. Noticeable temperature-correlated intraspecific variability was found in both body and tail scale counts but not in head scalation features. Generally, both males and females demonstrate the same phenotype-environment correlation. The spatial variations in external morphology suggest that temperature conditions during early ontogenesis may induce quantitative changes in the scalation pattern of V. palaestinae.

关 键 词：Vipera palaestinae geographic variability scalation pattern temperature-dependent trends VIPERIDAE 

分 类 号：Q958[生物学—动物学]