Fig. 5

Brachyury expression compared in the 3 species. The youngest embryos are at the top of the figure and the oldest at the bottom. In F.lizardensis, age matched embryos are shown in lateral view on the left and oral view on the right. The earliest expression seen is on the rim of the bowl-shaped embryo surrounding the blastopore (a-b). Expression continues around the blastopore/oral pore, as it closes (c-h). C.echinata expression (i-l) develops in a similar way, first appearing on the rim of the bowl-shaped embryo, with expression continuing as the blastopore gradually closes. In A.millepora (m-p), the general pattern is similar, with Ambra expression appearing around the blastopore as it forms at the end of the prawn chip stage (m) and persisting as the blastopore gives rise to the oral pore (p)