title: Flexibility and control of thorax deformation during hawkmoth flight.
abstract: The interaction between neuromuscular systems and body mechanics plays an important role in the production of coordinated movements in animals. Lepidopteran insects move their wings by distortion of the thorax structure via the indirect flight muscles (IFMs), which are activated by neural signals at every stroke. However, how the action of these muscles affects thorax deformation and wing kinematics is poorly understood. We measured the deformation of the dorsal thorax (mesonotum) of tethered flying hawkmoths, Agrius convolvuli, using a high-speed laser profilometer combined with simultaneous recordings of electromyograms and wing kinematics. We observed that locally amplified mesonotum deformation near the wing hinges ensures sufficient wing movement. Furthermore, phase asymmetry in IFM activity leads to phase asymmetry in mesonotum oscillations and wingbeats. Our results revealed the flexibility and controllability of the single structure of the mesonotum by neurogenic action of the IFMs.
authors.affiliation: Research Center for Advanced Science and Technology, University of Tokyo, Meguro, Tokyo 153-8904, Japan ando@brain.imi.i.u-tokyo.ac.jp.
authors.forename: Noriyasu
authors.initials: N
authors.lastname: Ando
authors.affiliation: Research Center for Advanced Science and Technology, University of Tokyo, Meguro, Tokyo 153-8904, Japan.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Kanzaki
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D004576:Electromyography; D005426:Flight, Animal / Q000502:physiology; D008297:Male; D009036:Moths / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology; D013909:Thorax / Q000033:anatomy & histology; D014921:Wings, Animal
keywords: electromyogram; exoskeleton; indirect muscle; insect flight; synchronous muscle