Fig. 7. Effects of oil droplet filtering on the theoretical capture area of Anolis cristatellus visual pigments. The solid curves were obtained by multiplying smoothed, normalized visual pigment spectra by the associated smoothed, normalized oil droplet transmission spectra. The dotted lines are the smoothed visual pigment spectra. The numbers are the calculated capture areas under the filtered visual pigment spectra obtained by integration and expressed as a percentage of the unfiltered pigment capture area. The effect of the oil droplets on the long-wavelength-sensitive and medium-wavelength-sensitive (MWS) cones is to reduce short-wavelength absorbance while reducing overall absorbance by 17% and 5%, respectively. In these cases, there is no change in the absorbance maximum. However, the position of the oil droplet cut-off of the MWS cone reduces the capture area to 29% of that of the unfiltered pigment and moves the absorbance peak from 443 to 525 nm. This also produces a much steeper short-wavelength cut-off, which could improve color discrimination in an opponent processing system (see text).