Fig. 8. Schematic model of otic and epibranchial development. Competent non-neural ectoderm is acted on by FGF signalling (yellow) to induce Pax2-positive OEPD ectoderm by 5ss of chick development. After 7ss, FGF expression is attenuated and medial Wnt signalling (blue) emanating from the neural tube steers juxtaposed cells to an inner ear fate. Laterally, endodermal FGF signalling together with an unknown signal (red) cause OEPD to be routed into an epibranchial lineage.