Wood boring is a feature of several insect species and is a major cause of severe and irreparable damage to trees. Adult females typically deposit their eggs on the stem surface under bark scales. The emerging hatchlings live within wood during their larval phase, avoiding possible predation, whilst continually boring and tunneling through wood until pupation. A study of wood boring by insects offers unique insights into the bioengineering principles that drive evolutionary adaptations. We show that larval mandibles of the coffee wood stem borer beetle (Xylotrechus quadripes: Cerambycidae) have a highly sharp cusp edge to initiate fractures in Arabica wood and a suitable shape to generate small wood chips that are suitable for digestion. Cuticle hardness at the tip is significantly enhanced through zinc-enrichment. A hollow architecture significantly reduces bending stresses at the mandibular base without compromising the structural integrity. Finite element model of the mandible showed highest stresses in the tip region; these decreased to significantly lower values at the start of the hollow section. A scaling model based on a fracture mechanics framework shows the importance of the mandible shape in generating optimal chip sizes. These findings contain general principles in tool design and put in focus interactions of insects and their woody hosts.

木材无聊是几种昆虫的特征，并且是对树木造成严重和无法弥补的破坏的主要原因。成年雌性通常将树皮下的卵产于茎表面。刚孵出的幼体在其幼虫阶段生活在木材中，避免了可能的捕食，同时不断地在木材上钻孔和挖洞直至化up。昆虫对木材无聊的研究为驱动进化适应的生物工程原理提供了独特见解。我们表明，咖啡木茎bore甲虫（Xylotrechus quadripes：Cerambycidae ）的幼虫下颌骨具有尖锐的尖端，可在阿拉伯咖啡中引发骨折木材和合适的形状以产生适合消化的小木片。尖端的表皮硬度通过富锌得到显着提高。空心结构显着降低了下颌基部的弯曲应力，而不会损害结构的完整性。下颌骨的有限元模型在尖端区域显示出最大的应力。在空心部分开始时，这些值降低到明显更低的值。基于断裂力学框架的缩放模型显示出下颌骨形状在生成最佳切屑尺寸方面的重要性。这些发现包含了工具设计的一般原则，并着重讨论了昆虫及其木质宿主的相互作用。