Pike Nathan, Richard Denis, Foster William, Mahadevan L
Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK.
Proc Biol Sci. 2002 Jun 22;269(1497):1211-5. doi: 10.1098/rspb.2002.1999.
Insects provide examples of many cunning stratagems to cope with the challenges of living in a world dominated by surface forces. Despite being the current masters of the land environment, they are at constant risk of being entrapped in liquids, which they prevent by having waxy and hairy surfaces. The problem is particularly acute in an enclosed space, such as a plant gall. Using secreted wax to efficiently parcel and transport their own excrement, aphids were able to solve this problem 200 Myr ago. Here, we report on the physical and physiological significance of this ingenious solution. The secreted powdery wax has three distinct roles: (i) it is hydrophobic, (ii) it creates a microscopically rough inner gall surface made of weakly compacted wax needles making the gall ultra-hydrophobic, and (iii) it coats the honeydew droplets converting them into liquid marbles, that can be rapidly and efficiently moved.
昆虫提供了许多巧妙策略的例子，以应对生活在一个由表面力主导的世界中的挑战。尽管它们是当前陆地环境的主宰者，但它们始终面临被困在液体中的风险，而它们通过具有蜡质和多毛的表面来防止这种情况发生。在诸如植物虫瘿这样的封闭空间中，这个问题尤为严重。蚜虫在2亿年前就能够利用分泌的蜡有效地包裹和运输自身排泄物，从而解决了这个问题。在此，我们报告这种巧妙解决方案的物理和生理意义。分泌的粉状蜡有三个不同的作用：（i）它具有疏水性，（ii）它形成了一个微观粗糙的虫瘿内表面，该表面由疏松压实的蜡针组成，使虫瘿具有超疏水性，（iii）它覆盖在蜜露滴上，将它们转化为液滴弹珠，从而可以快速有效地移动。
