| 北草蜥个体发育过程中头部两性异形及食性的变化 |
| |
| 引用本文： | 张永普,计翔.北草蜥个体发育过程中头部两性异形及食性的变化[J].动物学研究,2000,21(3):181-186. |
| |
| 作者姓名： | 张永普 计翔 |
| |
| 作者单位： | [1]温州师范学院生物学系 [2]杭州师范学院生物学系 |
| |
| 基金项目： | 浙江省自然科学基金!青年人才专项基金，浙江省 15 1人才基金，杭州市人才基金资助项目 |
| |
| 摘 要： | 报道了北草蜥（Ｔａｋｙｄｒｏｍｕｓ ｓｅｐｔｅｎｔｒｉｏｎａｌｉｓ）的头部大小两性异形和食性在个体发育过程中的变化，讨论该种两性异形的进化选择压力。北草晰成体体长无显著的两性差异，两性异形主要表现为雄性个体有较大的头部（头长和头宽）。头部大小的两性异形在孵出幼体就已经存在。头部随ＳＶＬ的增长速率在个体发育的不同联合体是不同的，并随个体发育的进行变得更为显著。协方差分析显示，成年雌体特定ＳＶＬ的头部
|
| 关 键 词： | 北草蜥 两性异形 个体发育 性选择压力 进化 |
ONTOGENETIC CHANGES OF SEXUAL DIMORPHISM IN HEAD SIZE AND FOOD HABIT IN GRASS LIZARD,Takydromus septentrionalis |
| |
| Abstract: | Adult grass lizards,Takydromus septentrio nalis,are similar in size (SVL) but sexually dimorphic in head size (males' larger than females') throughout its range.A comprehensive analysis on the ecological and evolutionary sources of sexual differences in growth and size of heads requires a detailed understanding of growth trajectories during ontogeny.In this study,we specifically quesioned at what point during ontogeny males and females diverge in head size:at birth,during juvenile growth,or as mature adults? Our results indicate that males and females begin to diverge in head size at birth,although the divergence in the newly emerged young is much less pronounced than that in adults.An ANCOVA indicates that adult females even have smaller heads than do juveniles (including the newly emerged young).This suggests that adult females partition less resources into head growth but more into carcass growth,thereby leaving a larger space for eggs so as to increase reproductive output.Lizards collected in different seasons,from different populations,and at different ontogenetic stages,in various degrees,differ in food niche width and breadth.However,no direct evidence shows a substantial contribution of the divergence in head size to the segregation of food niche between males and females.Our analyses support that sexual selection is the main evolutionary source of smaller heads in female T.septentrionalis. |
| |
| Keywords: | Takydromus septentrionalis Sexual dimorphism Food habit Food niche overlap Food niche breadth |
| 本文献已被 CNKI 维普 等数据库收录！ |
| 点击此处可从《动物学研究》浏览原始摘要信息 |
|
点击此处可从《动物学研究》下载全文 |
|
