![]() We used an empirically derived profile drag coefficient measured from a revolving hummingbird wing, and bracketed our aerodynamic power estimates by assuming either high (0.469) or low (0.139) profile drag coefficients ( C D,pro ) corresponding to high (45°) and low (15°) angles of attack of the wing (23). The maximum power available to hummingbirds was calculated as the power margin: the ratio of the maximum power produced during load-lifting to the minimum power required for steady hovering. Morphological, kinematic, and power data were averaged for each gender of each species. The species mean is the average of the values for the two genders. All comparative data were analyzed by using least squares regression. In addition to analyses of raw species data, phylogenetic similarity among these data were corrected for by calculating standardized independent contrasts (24). In these cases, regressions were constrained to go through the origin (25). ![]() Each of the five independent Bayesian analyses conducted here appeared to have converged within Ϸ 500,000 generations. Nevertheless, to be conservative, we discarded the first 2 million generations of each analysis as burn-in. Recovered topologies and posterior probability values were highly correlated across the five independent analyses, again indicating that the chains had converged. The data corresponding to the final 13 million generations of each of the five independent analyses were ultimately pooled, allowing a consensus topology with mean branch lengths and posterior probability values to be calculated on the basis of 65,000 sample points (see Fig. Our analysis of two nuclear and one mitochondrial gene for the 75 ingroup taxa resulted in a well supported estimate of hummingbird phyloge- netic relationships. Of the 75 nodes on the tree, 62 received posterior probability values Ͼ 95%, and 53 of 75 received posterior probability values of 100. ![]() Morphology, Kinematics, and Aerodynamic Power. Morphological measurements were made for 484 captured individual hummingbirds from 43 species. Of the 43 species, 42 were included in the phylo- genetic estimate, which contained no polytomies (Fig.įlight trials were conducted on most of these individuals, but accurate kinematic data during maximal load lifts were available for only 347 individuals, but with all taxa represented. Thus, 41 ( n Ϫ 1) phylogenetically independent contrasts were available for comparative analyses.
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