Fig. 3.

UV (320–400 nm) vs. human-visible (400–700 nm) plumage reflectance among Anisognathus taxa. Each data point is the average of replicate spectra per plumage patch per individual for taxa examined (A. notabilis, A. flavinuchus venezuelanus, A. flavinuchus victorini, A. flavinuchus baezae, A. flavinuchus cyanopterus, A. flavinuchus sumptuosus, and A. flavinuchus flavinuchus). Human-visible color coded on gray-scale (white = blue; light gray = yellow, dark gray = blackish to olive). Note linear regression (solid line) and 95% confidence interval (dotted lines) of UV vs. human-visible reflectance among pigmented (black, olive, and yellow) colors, exclusive of dorsal plumage of A. notabilis (y = 0.043x + 205; adjusted r² = 0.7150, t = 11.02, P < 0.0001). Olive plumages (points for back, rump) of A. notabilis express UV reflectance levels comparable to those of blue plumages (accompanied by similar modifications to feather architecture; R.B., unpublished work) rather than to other pigmented feathers that look similar to humans.