Fattorini Simone
Department of Life, Health and Environmental Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy.
Biology (Basel). 2022 Dec 9;11(12):1794. doi: 10.3390/biology11121794.
The Dermaptera are an insect order exhibiting their highest diversity in the tropical areas of the southern hemisphere. This pattern has been considered a reflection of a Gondwanan origin. However, this hypothesis has not been tested through analytical methods. In this paper, the world distribution of earwigs was analysed by using the 'Cladistic Analysis of Distributions and Endemism' (CADE), a method which groups areas of endemism on the basis of shared distributions and phylogenetic relationships among taxa. In addition, clustering techniques were applied to depict biotic relationships based on similarity indices. Results of CADE support the idea that Gondwanan fragmentation exerted a crucial role in shaping the current distribution of the main clades of earwigs. However, the relationships between India with South East Asia suggested a biotic interchange occurred after the Indian collision with the Eurasian plate. The overall scenario emerging from cluster analyses revealed a strong influence of dispersal events. Overall, the distribution of earwig major clades indicates that their biogeographical history was mainly characterized by vicariance events (led by the break-up of Gondwana) followed by large scale dispersal processes constrained by the Himalayan orogenesis and the presence of colder temperatures, which have largely hampered the colonization of the northern hemisphere.
革翅目昆虫是一个昆虫目，在南半球的热带地区具有最高的多样性。这种分布模式被认为是冈瓦纳起源的一种反映。然而，这一假说尚未通过分析方法进行检验。在本文中，运用“分布与特有性的分支分析”（CADE）方法对蠼螋的全球分布进行了分析，该方法基于类群之间的共同分布和系统发育关系对特有区域进行分组。此外，还应用聚类技术根据相似性指数描绘生物关系。CADE的结果支持了这样一种观点，即冈瓦纳大陆的分裂在塑造蠼螋主要类群的当前分布中发挥了关键作用。然而，印度与东南亚之间的关系表明，在印度与欧亚板块碰撞之后发生了生物交换。聚类分析得出的总体情况显示了扩散事件的强烈影响。总体而言，蠼螋主要类群的分布表明，它们的生物地理历史主要以隔离分化事件（由冈瓦纳大陆的分裂导致）为特征，随后是受喜马拉雅造山运动和较低温度的影响而受到限制的大规模扩散过程，这些因素在很大程度上阻碍了北半球的定殖。
