Top row: dorsal fluorescence intensity profile(s) from simultaneously stained embryos (mean ± SD); units scaled so that 0 (1) corresponds to minimum (maximum) mean expression. Bottom row: decoding maps, P(x*∣x) from Equation (4), averaged over 38 embryos. (A) Decoding using single gene (Kr, blue) (also Figures 2 and S1C). (B) Decoding using a combination of two genes, Kr (blue) and Hb (red) (also Figure S1D). (C) Decoding using three genes, Kr (blue), Hb (red), and Gt (orange) (also Figure S1E). (D) Decoding using all four gap genes. See also Figure S1.