title: Natural flexible dermal armor.
abstract: Fish, reptiles, and mammals can possess flexible dermal armor for protection. Here we seek to find the means by which Nature derives its protection by examining the scales from several fish (Atractosteus spatula, Arapaima gigas, Polypterus senegalus, Morone saxatilis, Cyprinius carpio), and osteoderms from armadillos, alligators, and leatherback turtles. Dermal armor has clearly been developed by convergent evolution in these different species. In general, it has a hierarchical structure with collagen fibers joining more rigid units (scales or osteoderms), thereby increasing flexibility without significantly sacrificing strength, in contrast to rigid monolithic mineral composites. These dermal structures are also multifunctional, with hydrodynamic drag (in fish), coloration for camouflage or intraspecies recognition, temperature and fluid regulation being other important functions. The understanding of such flexible dermal armor is important as it may provide a basis for new synthetic, yet bioinspired, armor materials.
authors.affiliation: Materials Science and Engineering Program, University of California, San Diego, La Jolla, 92093, USA.
authors.forename: Wen
authors.initials: W
authors.lastname: Yang
authors.forename: Irene H
authors.initials: IH
authors.lastname: Chen
authors.forename: Bernd
authors.initials: B
authors.lastname: Gludovatz
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Zimmermann
authors.forename: Robert O
authors.initials: RO
authors.lastname: Ritchie
authors.forename: Marc A
authors.initials: MA
authors.lastname: Meyers
mesh_terms: D000825:Animal Structures; D000818:Animals; D001696:Biomechanical Phenomena; D055595:Mechanical Phenomena; D011235:Predatory Behavior; D012867:Skin