1A, 1B
Vegetal view of early gastrula stage X. laevis and S. tropicalis embryos, respectively. Arrowheads denote dorsal lip of the blastopore.
1C, 1D
Dorsal view of neural plate stage X. laevis and S. tropicalis embryos, respectively. The dark vertical indentation in the center of each embryo is the floorplate of the presumptive neural tube.
1E, 1F
Dorsal view of neural tube stage X. laevis and S. tropicalis embryos, respectively. Arrows denote region of neural fold fusion.
1G, 1H
Tadpole stages of X. laevis and S. tropicalis embryos, respectively, at approximately the same developmental age.