title: Understanding and mimicking the dual optimality of the fly ear.
abstract: The fly Ormia ochracea has the remarkable ability, given an eardrum separation of only 520 μm, to pinpoint the 5 kHz chirp of its cricket host. Previous research showed that the two eardrums are mechanically coupled, which amplifies the directional cues. We have now performed a mechanics and optimization analysis which reveals that the right coupling strength is key: it results in simultaneously optimized directional sensitivity and directional cue linearity at 5 kHz. We next demonstrated that this dual optimality is replicable in a synthetic device and can be tailored for a desired frequency. Finally, we demonstrated a miniature sensor endowed with this dual-optimality at 8 kHz with unparalleled sound localization. This work provides a quantitative and mechanistic explanation for the fly's sound-localization ability from a new perspective, and it provides a framework for the development of fly-ear inspired sensors to overcoming a previously-insurmountable size constraint in engineered sound-localization systems.
authors: Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA.
authors: Haijun
authors: H
authors: Liu
authors: Luke
authors: L
authors: Currano
authors: Danny
authors: D
authors: Gee
authors: Tristan
authors: T
authors: Helms
authors: Miao
authors: M
authors: Yu
mesh_terms: D000465:Algorithms; D000818:Animals; D055592:Biophysical Phenomena; D015374:Biosensing Techniques / Q000295:instrumentation; D004175:Diptera / Q000502:physiology*; D004423:Ear / Q000502:physiology*; D008954:Models, Biological; D013017:Sound Localization
references: Curr Opin Neurobiol. 2002 Dec;12(6):715-20
references: 12490264
references: J Acoust Soc Am. 1995 Dec;98(6):3059-70
references: 8550933
references: Nature. 2001 Apr 5;410(6829):686-90
references: 11287954
references: Nat Neurosci. 2009 Jun;12(6):692-7
references: 19471267
references: Audiol Neurootol. 2006;11(2):86-94
references: 16439831
references: J Acoust Soc Am. 2009 Apr;125(4):2013-26
references: 19354377
references: J Comp Physiol A. 1996;179(1):29-44
references: 8965258
references: Science. 1992 Nov 13;258(5085):1135-7
references: 1439820
references: Science. 2010 Feb 5;327(5966):701-4
references: 20133574
references: Hear Res. 2000 Nov;149(1-2):1-10
references: 11033242