象虫是昆虫纲鞘翅目象虫总科的通称，是昆虫纲中种类最多的类群。象虫的额向前延伸形成“喙”，成为区别于其他鞘翅目昆虫最独特的结构。喙不但可以帮助象虫取食植物内部组织，而且具有辅助产卵的功能，从而以较少产卵量和较少能量消耗以及高后代成活率保持种群。为适应不同寄主，象虫喙有显著的适应性变化，喙的演化也被认为是象虫物种辐射爆发的关键。申请人对象虫亚科水平进行初步研究后发现，象虫喙具有显著的系统发育信号，其形态与产卵习性等功能对应程度较高。因此，本项目拟选取3类典型的代表类群进行深入研究。通过提取喙二维和三维形状变量，结合寄主植物取食和产卵位点数据对象虫形态适应性机制进行探索。通过建立系统发育树，结合上述形态、分子演变过程，综合分析与寄主的系统演化关系，从而探讨象虫喙的系统发育信号及其与寄主协同进化关系，渴望从多层次揭示象虫物种繁多的适应性辐射机制。预期发表学术论文2-3篇，培养研究生2-3人。

Weevil (Coleoptera: Curculionoidea) is one of the most diversity groups of Insecta. Its unique structure which can be clearly distinguished is “rostrum”. Most species of weevil are phytophages, and the rostrum can not only assist them in feeding the inner tissue of the hosts but also assist in oviposition. Consequently, weevil is successful in maintain the population by keeping high larva survival probability but low amount of eggs and energy consumption. To adapt variable hosts, the weevil rostrum performs great morphological diversity. It is supposed that the rostrum is one of the most important key for the diversification of weevils. The proposer has preliminarily studied subfamily level of the superfamily Curculionoidea and found that the rostrum represented distinct phylogenetic signals and had a strong correlation between morphology and function. The present proposal aims to find a relationship between morphometrical multivariate of 3 weevil groups with typical representative rostrums and the host plants. Moreover, by integrating the DNA and morphological data, a phylogenetic tree will be established to compare with 2D and 3D data of the rostrum for studying the evolutionary signal of rostrum morphometrical multivariate will be analyzed and discussed.