Fig. 9.

The influence of environmental richness on the sensitive period for the adjustment of sound localization accuracy in response to prism experience. Each data point represents the mean (±SD) auditory orientation error measured for an individual owl after at least 60 d of experience with 23° prisms; positive errors indicate shifts in the adaptive direction. A, These data are from a previous study (Knudsen and Knudsen, 1990) and show the effect of prism experience on sound localization accuracy for owls housed in individual cages. B, The open symbols represent data from three owls measured in this study and show the adjustment of sound localization accuracy for owls housed in large aviaries. The data from A areshaded and plotted for comparison. The data fromowl Sp (□) indicate adjustment of sound localization accuracy at an age when little adjustment occurred in owls housed in individual cages (compare with owl Sh inA). No adjustment occurred in the adult owl, owl Gy (○), although it was housed in a large aviary.