Department of Chemical and Environmental Engineering, Materials Science and Engineering Bldg. Room 343, UC Riverside, Riverside, CA, 92521, USA.
Lyles School of Civil Engineering, Purdue University, West Lafayette, IN, 47907, USA.
Adv Mater. 2018 Mar;30(9). doi: 10.1002/adma.201705295. Epub 2018 Jan 16.
Ecological pressures and varied feeding behaviors in a multitude of organisms have necessitated the drive for adaptation. One such change is seen in the feeding appendages of stomatopods, a group of highly predatory marine crustaceans. Stomatopods include "spearers," who ambush and snare soft bodied prey, and "smashers," who bludgeon hard-shelled prey with a heavily mineralized club. The regional substructural complexity of the stomatopod dactyl club from the smashing predator Odontodactylus scyllarus represents a model system in the study of impact tolerant biominerals. The club consists of a highly mineralized impact region, a characteristic Bouligand architecture (common to arthropods), and a unique section of the club, the striated region, composed of highly aligned sheets of mineralized fibers. Detailed ultrastructural investigations of the striated region within O. scyllarus and a related species of spearing stomatopod, Lysiosquillina maculate show consistent organization of mineral and organic, but distinct differences in macro-scale architecture. Evidence is provided for the function and substructural exaptation of the striated region, which facilitated redeployment of a raptorial feeding appendage as a biological hammer. Moreover, given the need to accelerate underwater and "grab" or "smash" their prey, the spearer and smasher appendages are specifically designed with a significantly reduced drag force.
生态压力和多种生物体的不同摄食行为促使它们不断适应环境。这种变化在口足目动物（一种高度捕食性的海洋甲壳类动物）的摄食附肢中可见一斑。口足目动物包括“刺击者”，它们伏击和捕捉柔软的猎物，以及“粉碎者”，它们用重矿物化的棍棒猛击硬壳猎物。粉碎者掠食性十足的 Odontodactylus scyllarus 的口足目足指的区域亚结构复杂性代表了抗冲击生物矿物研究的一个模型系统。该足指由高度矿化的冲击区、特征性的 Bouligand 结构（常见于节肢动物）和独特的条纹区组成，由高度排列的矿化纤维组成。对 O. scyllarus 和相关的刺击口足目动物 Lysiosquillina maculate 的条纹区进行详细的超微结构研究表明，矿物质和有机物的组织一致，但宏观结构存在明显差异。为条纹区的功能和亚结构适应提供了证据，这促进了捕食性附肢作为生物锤的重新配置。此外，由于需要在水下加速并“抓住”或“粉碎”它们的猎物，刺击者和粉碎者的附肢专门设计成具有显著降低的阻力。
