Only E16.5 cerebella that showed regional thickening in the geometry where ACs normally arise were used for the measurements, and one embryo did not yet have an AC3. (A–C) Thickness variation in and surrounding AC1 (anova (A) df = 17, p=0.13, F = 1.55 (B) df = 29, p=7.0e−14, F = 6.82 (C) df = 57, p=9.1e−11, F = 4.05). (D–F) Thickness variation in and surrounding AC2 (anova (D) df = 17, p=0.08, F=1.74 (E) df = 29 P=3.9e−22, F = 11.88 (F) df = 57 P=2.9e−35, F = 16.35). (G–I) Thickness variation in and surrounding AC3 (anova (G) df = 17, p=0.59, F=0.89 (H) df = 29, p=2.4e−17, F = 9.81 (I) df = 57, p=7.6e−33, F = 14.57). Error bars are S.D.