Flying insects solve a daunting control problem of generating a patterned and precise motor program to stay airborne and generate agile maneuvers. In this motor program, each muscle encodes information about movement in precise spike timing down to the millisecond scale. Whereas individual muscles share information about movement, we do not know if they have separable effects on an animal's motion, or if muscles functionally interact such that the effects of any muscle's timing depend heavily on the state of the entire musculature. To answer these questions, we performed spike-resolution electromyography and electrical stimulation in the hawkmoth Manduca sexta during tethered flapping. We specifically explored how flight power muscles contribute to pitch control. Combining correlational study of visually-induced turns with causal manipulation of spike timing, we discovered likely coordination patterns for pitch turns, and investigated if these patterns can drive pitch control. We observed significant timing change of the main downstroke muscles, the dorsolongitudinal muscles (DLMs), associated with pitch turns. Causally inducing this timing change in the DLMs with electrical stimulation produced a consistent, mechanically relevant feature in pitch torque, establishing that power muscles in Manduca have a control role in pitch. Because changes were evoked in only the DLMs, however, these pitch torque features left large unexplained variation. We find this unexplained variation indicates significant functional overlap in pitch control such that precise timing of one power muscle does not produce a precise turn, demonstrating the importance of coordination across the entire motor program for flight.
Flight power muscles have a coordinated, causal role in hawkmoth pitch turns
- Award Group:
- Funder(s): Air Force Office of Scientific Research
- Award Id(s): FA9550-19-1-0396
- Funder(s):
- Award Group:
- Funder(s): Klingenstein-Simons Fellowship Award in Neuroscience
- Funder(s):
- Award Group:
- Funder(s): Dunn Family Endowment
- Funder(s):
Leo Wood, Joy Putney, Simon Sponberg; Flight power muscles have a coordinated, causal role in hawkmoth pitch turns. J Exp Biol 2024; jeb.246840. doi: https://doi.org/10.1242/jeb.246840
Download citation file:
Advertisement
Cited by
Special Issue – The Integrative Biology of the Heart
Our latest Special Issue – The Integrative Biology of the Heart collates Research Articles, Reviews and Commentaries that consider cardiac biology at all levels of organisation. Guest edited by William Joyce and Holly Shiels, the papers address questions regarding cardiac plasticity, development and evolution in both vertebrates and invertebrates.
Sensory perception in a changing world – join us in Liverpool in March 2025
We are excited to invite you to a unique scientific conference, celebrating the 100-year anniversary of The Company of Biologists, and bringing together our different communities. The conference will incorporate the JEB Symposium Sensory Perception in a Changing World and the SEB satellite meeting. Find out more and register to join us in March 2025 in Liverpool, UK. Submit your abstract by 13 December 2024. Early-bird registration ends on 17 January 2025.
Extraordinary creatures: raptors
In our new Conversation focusing on extraordinary creatures, Simon Potier tells us about raptors, from peregrine falcons and eagles to vultures and owls, discussing their lifestyles, incredible sensory abilities and conservation successes.
Creating more realistic conditions for in vitro research on the fish GI
In this Commentary, Carol Bucking and colleagues discuss the issues associated with replicating in vivo conditions of the teleost gastrointestinal (GI) tract in in vitro work, and identify solutions and areas of improvement. Mimicking realistic GI conditions has the potential to greatly improve our knowledge on basic fish gut physiology.
Crude oil destroys sea otter buoyancy
The sight of animals slathered in crude oil is immensely distressing and now Kate Riordan & colleagues reveal that oil pollution decimates sea otter buoyancy and how cleaning them with detergent only partially restores the otters' ability to float.