Fig. 5. The relationship between wing loading (kg m^-2) and elevation (m) for hummingbirds: (A) means of raw species data (y=-0.002x+26, r²=0.196, P=0.003); (B) independent contrasts (y=-0.11x; r²=0.18, P=0.04). The regression using independent contrasts in forced through the origin (Garland et al., 1992). The phylogenetic hypothesis used for this analysis is the same as for Fig. 1.