近日中科院动物所鞘翅目形态与进化研究组的研究人员在昆虫后翅形态进化研究中获得新进展,相关研究论文发表在美国《公共科学图书馆—综合》(PLoS ONE)杂志上。
领导这一研究的是中国科学院动物研究所鞘翅目形态与进化研究组组长杨星科研究员,其长期从事鞘翅目、脉翅目等昆虫类群的系统学和昆虫地理学研究。先后在国内外刊物上发表有关研究报告或论文近200篇,其中近五年发表SCI源论文20余篇,发现新属4个、新种200余个。
昆虫是地球上最繁盛的生物类群,翅的获得在昆虫演化历程中扮演了重要角色。长久以来,后翅特征在昆虫的识别和种类鉴定中就已获得广泛应用且具重要价值。伴随着支序系统学的发展,后翅成为系统发育研究中非常重要的特征来源。但是后翅的形态是否能够反映整个昆虫的系统发育并未获得证实。而且前人对后翅形态进化的研究,通常基于传统定性的方法对一定种类进行研究,或者是基于定量的方法对少数种类(如果蝇等模式生物)进行研究。利用定量的研究方法对大量种类后翅进化的研究还未见报道。
研究人员利用支序系统学和几何形态学研究方法,基于81种蜣螂(鞘翅目:金龟科),选取了19个后翅标点和119个形态特征,发现基于后翅形态的几何形态学树与基于119个形态特征的系统发育树高度相关,这就说明了后翅进化与整个身体进化高度相关。通过进一步研究发现,后翅并非与身体所有部位的进化都相关,主要与胸部和腹部相关性最高。通过对蜣螂后翅的形态变异程度评价研究,我们发现原始种类后翅形态趋于多样化。另外,我们通过对蜣螂祖先后翅形态的推断,发现在蜣螂进化过程中,后翅形态总体趋于稳定(尤其是R、M脉),从而证实了蜣螂后翅的飞行功能自起源以来没有显著变化。通过整合支序系统学和几何形态学研究方法,本研究为昆虫后翅形态进化研究提供了新的思路和方向。
该研究由中国科学院动物研究所杨星科领导的团队历时近6年完成,团队成员中白明副研究员留学期间所检视的保存在欧洲等国14个知名博物馆的模式标本,为本研究奠定了坚实基础。该研究获得了来自国家自然基金委、中科院和科技部(973)的资助。(生物谷Bioon.com)
生物谷推荐原文出处:
PLoS ONE doi:10.1371/journal.pone.0021600
Evolutionary Constraints in Hind Wing Shape in Chinese Dung Beetles (Coleoptera: Scarabaeinae)
Ming Bai, Erin McCullough, Ke-Qing Song, Wan-Gang Liu1, Xing-Ke Yang
This study examines the evolution hindwing shape in Chinese dung beetle species using morphometric and phylogenetic analyses. Previous studies have analyzed the evolution of wing shape within a single or very few species, or by comparing only a few wing traits. No study has analyzed wing shape evolution of a large number of species, or quantitatively compared morphological variation of wings with proposed phylogenetic relationships. This study examines the morphological variation of hindwings based on 19 landmarks, 119 morphological characters, and 81 beetle species. Only one most parsimonious tree (MPT) was found based on 119 wing and body characters. To better understand the possible role of the hindwing in the evolution of Scarabaeinae, additional phylogenetic analyses were proposed based on the only body features (106 characters, wing characters excluded). Two MPT were found based on 106 body characters, and five nodes were collapsed in a strict consensus. There was a strong correlation between the morphometric tree and all phylogenetic trees (r>0.5). Reconstructions of the ancestral wing forms suggest that Scarabaeinae hindwing morphology has not changed substantially over time, but the morphological changes that do occur are focused at the base of the wing. These results suggest that flight has been important since the origin of Scarabaeinae, and that variation in hindwing morphology has been limited by functional constraints. Comparison of metric disparity values and relative evolutionary sequences among Scarabaeinae tribes suggest that the primitive dung beetles had relatively diverse hindwing morphologies, while advanced dung beetles have relatively similar wing morphologies. The strong correlation between the morphometric tree and phylogenetic trees suggest that hindwing features reflect the evolution of whole body morphology and that wing characters are suitable for the phylogenetic analyses. By integrating morphometric and cladistic approaches, this paper sheds new light on the evolution of dung beetle hind wings.