青藏高原褐背拟地鸦表型特征的性别差异与地理变异

SEXUAL AND GEOGRAPHIC PHENOTYPIC VARIATION OF THE BROWN GROUND CHOUGH PSEUDOPODOCES HUMILIS IN THE TIBETAN PLATEAU,CHINA

将数值分类用于鸟类分类学研究时 ,对于雌雄的形态特征差异没有被重视 ,尤其是对于雌雄同形的鸟类。本文以雌雄同形的褐背拟地鸦Pseudopodoceshumilis为材料 ,运用SPSS 10 0FORWINDOWS统计分析软件对 10 8号褐背拟地鸦标本 ( 5 1♀♀ ,5 7♂♂ )的数量性状 (体长、跗长、翅长、尾长、嘴宽、嘴高、上喙长、下喙长、嘴裂、第 3趾爪长、第 1趾爪长 )的原始数据进行分析 ,结果表明雌、雄性状在翅长 (n =5 1,P =0 0 12 )和嘴高(n =5 7,P =0 0 43 )上有明显差异 ,但在体长、跗长、尾长、嘴宽、上喙长、下喙长、嘴裂、第 3趾爪长、第 1趾爪长等数值特征上却没有明显的差异。所以在以后对于褐背拟地鸦的地理种群变异和亚种分化的研究中 ,翅长和嘴高两特征应该根据雌雄分别讨论。通过对不同性状量度和纬度的相关回归分析 ,发现在测量标本所涉及的采集地范围内 ,即主要在青藏高原东南部地区 ,褐背拟地鸦体长和雄鸟的翅长在地理分布上随纬度的增加而变小 。

When numerical methods have been used in avian taxonomy, inter-sexual phenotypic variation has always been neglected, especially in species without obvious sexual dimorphism. In this paper, we firstly analyzed morphometric differences between male and female brown ground choughs (Pseudopodoces humilis), a species without obvious sexual dimorphism, and then analyzed geographic variation in morphological characters within this species in the Tibetan Plateau. The original data came from 108 specimen and included body weight, body length, tarsus length, wing length, tail length, bill width, bill height, upper mandible length, lower mandible length, gape length, the claw length of the third toe and the claw length of the first toe. After analyzing these data, significant differences between male and female were found in wing length (n=51, P=0.012) and bill height (n=57, P=0.043) but not in other characters. Consequently, we intend to incorporate sexual phenotypic differences in a planned future study of geographical variation and subspecies differentiation in the brown ground chough. Regression analyses revealed that some morphological characteristics were positively related to latitude, we also found that body length and male wing length were negatively correlated with latitude in our specimens, all of which were captured on the east and south of the Tibetan Plateau. Other morphological parameters did not have such an obvious correlation with latitude.