Table 1. Difference in plumage colorfulness among Anisognathus taxa.

	No. of patches that differ in color*
Taxon comparison	Without UV (human)	With UV (avian)
Sympatric species
igniventris vs. lacrymosus	8	8
flavinuchus vs. notabilis	3	6
Allopatric species
lacrymosus vs. melanogenys	3	3
Subspecies†
igniventris, lacrymosus, and flavinuchus	0-2	0-2

Plumage colorfulness was based on number of different colorful plumage patches among 14 standard regions (see below). Color vision in both birds and humans is based on differential stimulation of populations of different cone classes by nonuniform physical reflectance. Therefore, plumage reflectance spectra with well defined local (peaks and troughs) and/or absolute (step-functions) maxima or minima (see Fig. 2) should be deemed colorful to both birds and humans (23). By the avian standard, the UV-reflecting dorsal plumage of A. notabilis qualifies as colorful, even though this plumage appears dull-colored to humans.

^*Excludes comparisons among noncolorful black, brown, olive, or white patches. Patches scored: forecrown, hindcrown, back, rump, upper-tail coverts, throat, breast, belly, under-tail coverts, face, auriculars, thigh, wing, and tail.

^†Subspecies not enumerated.