Hoch Hannelore, Pingel Martin, Voigt Dagmar, Wyss Urs, Gorb Stanislav
Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, 10115 Berlin, Germany.
Botany, Faculty of Biology, Technische Universität Dresden, 01062 Dresden, Germany.
J R Soc Interface. 2024 Jan;21(210):20230521. doi: 10.1098/rsif.2023.0521. Epub 2024 Jan 10.
spittlebug nymphs produce a wet foam from anal excrement fluid, covering and protecting themselves against numerous impacts. Foam fluid contact angles on normal (26°) and silanized glass (37°) suggest that the foam wets various substrates, including plant and arthropod surfaces. The pull-off force depends on the hydration state and is higher the more dry the fluid. Because the foam desiccates as fast as water, predators once captured struggle to free from drying foam, becoming stickier. The present study confirms that adhesion is one of the numerous foam characteristics resulting in multifunctional effects, which promote spittlebugs' survival and render the foam a smart, biocompatible material of biological, biomimetic and biomedical interest. The sustainable 'reuse' of large amounts of excrement for foam production and protection of the thin nymph integument suggests energetic and evolutionary advantages. Probably, that is why foam nests have evolved in different groups of organisms, such as spittlebugs, frogs and fish.
沫蝉若虫从肛门排泄物中分泌出一种湿润的泡沫，覆盖并保护自己免受多种伤害。泡沫在普通玻璃（26°）和硅烷化玻璃（37°）上的接触角表明，这种泡沫能湿润包括植物和节肢动物体表在内的各种基质。剥离力取决于水合状态，流体越干燥，剥离力越高。由于泡沫干燥速度与水一样快，被捕食者一旦被捕获，就会挣扎着从干燥的泡沫中挣脱出来，而泡沫会变得更粘。本研究证实，粘附是众多泡沫特性之一，这些特性产生了多功能效应，促进了沫蝉的生存，并使泡沫成为一种具有生物学、仿生学和生物医学意义的智能、生物相容性材料。大量排泄物用于泡沫生产以及保护若虫薄外皮的可持续“再利用”显示出能量和进化上的优势。也许，这就是为什么泡沫巢穴在不同的生物群体中进化出来，比如沫蝉、青蛙和鱼类。
