1D maps in wild-type and knock-in animals. A. column of results for wild-type conditions. B. Column corresponding to heterozygous Isl2/Eph3 knock-in conditions. The bifurcation of the probability distribution is similar to results of Ref.  (see Figure 2 above). C. Results for homozygous knock-in conditions. For all three conditions, the top row represents distributions of chemical labels. The second row shows the probability distributions. The brightness of color at each point in the middle image represents probability that an axon originating from the horizontal position projects to the point's vertical position. The bottom row shows positions of maxima of probability density distributions displayed above. The red squares correspond to wild-type cells; black markers determine maxima of distributions for Isl2+/EphA3+ RGCs. A slight even-odd oscillation observed in these panels is an artifact of ordering of wild-type and EphA3+ axons in retina. The bottom row shows maps obtained by sorting retinal receptor density.