Fig. 1: The evolution of mantle darkness in the Larinae and its relationship with wing loading and absolute latitude.
From: Dark wing pigmentation as a mechanism for improved flight efficiency in the Larinae
Branches show the estimated ancestral states of mantle darkness, with the current, observed states at the tips. The relative values of standardized wing loading (W) and absolute latitude (A, distance from the equator in degrees) are shown by coloured circles, along with the approximate mantle darkness of each species on the Kodak grey scale (squares). The height of the phylogenetic tree is 0.21 million years. Note: genus names of the original BirdTree phylogeny have been amended to reflect current nomenclature.
