School of Biosciences, Faculty of Science, The University of Melbourne, Melbourne, Australia.
Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Kiel, Germany.
J R Soc Interface. 2023 Nov;20(208):20230447. doi: 10.1098/rsif.2023.0447. Epub 2023 Nov 22.
Enhanced attachment ability is common in plants on islands to avoid potential fatal passive dispersal. However, whether island insects also have increased attachment ability remains unclear. Here we measured the attachment of a flightless weevil, , from tropical islands, and compared it with documented arthropods from the mainland. We examined the morphology and material gradient of its attachment devices to identify the specific adaptive modifications for attachment. We find that the weevil has much stronger attachment force and higher safety factor than previously studied arthropods, regardless of body size and substrate roughness. This probably results from the specific flexible bases of the adhesive setae on the third footpad of the legs. This softer material on the setal base has not been reported hitherto and we suggest that it acts as a flexible hinge to form intimate contact to substrate more effectively. By contrast, no morphological difference in tarsomeres and setae between the weevil and other beetles is observed. Our results show the remarkably strong attachment of an island insect and highlights the potential adaptive benefits of strong attachment in windy island environment. The unique soft bases of the adhesive hairs may inspire the development of strong biomimetic adhesives.
增强的附着能力在岛屿上的植物中很常见，以避免潜在的致命被动扩散。然而，岛屿上的昆虫是否也具有增强的附着能力尚不清楚。在这里，我们测量了一种来自热带岛屿的无飞行象鼻虫的附着能力，并将其与大陆上有记录的节肢动物进行了比较。我们研究了其附着装置的形态和材料梯度，以确定特定的适应性附着改造。我们发现，无论体型大小和基质粗糙度如何，象鼻虫的附着力和安全系数都比以前研究过的节肢动物强得多。这可能是由于腿部第三脚垫上的粘性刚毛的特殊柔性基底造成的。到目前为止，还没有报道过这种刚毛基部更柔软的材料，我们认为它作为一个柔性铰链，可以更有效地与基质形成紧密接触。相比之下，我们没有观察到象鼻虫和其他甲虫的跗节和刚毛之间有形态上的差异。我们的研究结果表明，岛屿昆虫具有非常强的附着能力，突出了在多风的岛屿环境中强附着的潜在适应性优势。粘性刚毛独特的柔软基底可能为开发强仿生粘合剂提供灵感。
