JACKSON, B.E.*; DIAL, K.P.; Univ. of Montana, Missoula; Univ. of Montana, Missoula: Allometry of avian flight performance: contribution of legs and wings during maximal burst takeoff and vertical flight
Previous work on bird takeoff and vertical flight has been relatively limited either by the selection of the performance variables or by the phylogenetic scope of the study. In an effort to comprehensively measure the allometry of flight performance, we are quantifying the burst vertical, burst horizontal, and high-speed angular accelerations for a range of species and body masses. Here we present our progress to date on whole-body performance, detailed 3D wingbeat kinematics, and hindlimb power production during maximal burst takeoff and vertical flight. We used a force plate and four synchronized high-speed video cameras to quantify the relative contributions of both legs and wings during lift-off, as well as the 3-D kinematics and dynamic morphology of birds flying vertically (2.5 m). Among species of columbids (N=4; mass range 40g – 480g), wing span, wingbeat frequency, and mass specific whole-body take off power scale as predicted by isometry and the frequency-dependent power hypothesis: proportional to M-1/3. However, in the current sample of passerine species (N=8; 9g � 78g) wing span scales in proportion to M0.20, frequency as M-0.19, and take off power is independent of body mass. Both peak ground reaction force (mean 5.0 X body weight) and mass-specific hindlimb jump power (mean 49 Wkg-1) are independent of body mass in both the columbids and passerines, with no significant differences between clades. While flight performance in galliforms (N=4 species from Tobalske and Dial 2000) and the columbids scales predictably from the frequency-dependent power hypothesis, the pattern in passerines is less clear and will require an evaluation over the full range of body sizes and ecologies within this highly speciose clade. (Supported by NSF)
