Meeting Abstract
Bats show outstanding flight agility and control. Yet, they often fly through windy conditions and in close proximity, so they collide often. They minimize the impact of these collisions through their ability to quickly recover stable flight. Here, we investigate the motor control of the pectoralis major muscle during recovery maneuvers of Rousettus aegyptiacus. Previous studies perturbing terrestrial vertebrates reveal a graded pattern of muscle activation during the recovery response, involving load-sensitive recruitment of distal muscles and load-insensitive recruitment of proximal muscles. We hypothesized that the right and left pectoralis in bats would maintain synchronous activation throughout a flight perturbation. To test this, we trained five bats to fly through a corridor with six high-speed video cameras, while collecting electrical activity of bilateral pectoralis recruitment from electromyogram electrodes attached to a wireless data logger (Vesper Pipistrelle, 4.1g). Bats flew through a window in a divider bisecting the corridor. On test trials, an air jet 2.5x their body weight struck one wing at this moment. We analyzed spatial position using camera recordings of 15 marks on each bat, and compared this set with the timing of the electromyogram data. All trials showed symmetrical recruitment in the pectoralis major muscles. We conclude that proximal muscle recruitment in our model bat species is not altered by a significant perturbation during flight. Similarly to the limb control model in terrestrial vertebrates, bats maintain proximal muscle control that is independent from the force of a perturbation.
