Bioreplicated visual features of nanofabricated buprestid beetle decoys evokestereotypical male mating flights
Michael J. Domingue, Akhlesh Lakhtakia, Drew P. Pulsifer, Loyal P. Hall, John V. Badding,Jesse L. Bischof, Raúl J. Martín-Palma, Zoltán Imrei, Gergely Janik, Victor C. Mastro, Missy Hazen,and Thomas C. Baker
Recent advances in nanoscale bioreplication processes present the potential for novel basic and applied research into organismal behavioral processes. Insect behavior potentially could be affected by physicalfeatures existing at the nanoscale level. We used nano-bioreplicated visual decoys of female emerald ash borer beetles (Agrilus planipennis) to evoke stereotypical mate-finding behavior, whereby males fly to and alight on the decoys as they would on real females. Using an industrially scalABLe nanomolding process, we replicated and evaluated the importance of two features of the outer cuticular surfAce of thebeetle’s wings: structural interference coloration of the elytra by multilayering of the epicuticle and fine-scale surface features consisting of spicules and spines that scatter light into intense strands. Two types ofdecoys that lacked one or both of these elements were fabricated, one type nano-bioreplicated and the other 3D-printed with no bioreplicated surface nanostructural elements. Both types were colored with green paint. The light-scattering properties of the nano-bioreplicated surfaces were verified by shining a white laser on the decoys in a dark room and projecting the scattering pattern onto a white surface. Regardless of the coloration mechanism, the nano-bioreplicated decoys evoked the complete attraction and landing sequence of Agrilus males. In contrast, males made brief flying approaches toward the decoyswithout nanostructured features, but diverted away before alighting on them. The nano-bioreplicateddecoys were also electroconductive, a feature used on traps such that beetles alighting onto them were stunned, killed, and collected.
