Neuromuscular control of wingbeat kinematics in Anna's hummingbirds (Calypte anna).

ABSTRACT: Hummingbirds can maintain the highest wingbeat frequencies of any flying vertebrate - a feat accomplished by the large pectoral muscles that power the wing strokes. An unusual feature of these muscles is that they are activated by one or a few spikes per cycle as revealed by electromyogram recordings (EMGs). The relatively simple nature of this activation pattern provides an opportunity to understand how motor units are recruited to modulate limb kinematics. Hummingbirds made to fly in low-density air responded by moderately increasing wingbeat frequency and substantially increasing the wing stroke amplitude as compared with flight in normal air. There was little change in the number of spikes per EMG burst in the pectoralis major muscle between flight in normal and low-density heliox (mea

SUBMITTER: Altshuler DL 

PROVIDER: S-EPMC2892424 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature