Movie 1.

Patiria miniata WT embryo, vegetal view. Maximum projection of confocal time-lapse video of a WT embryo expressing a membrane marker (mYFP, yellow) and a nuclear marker (n-CFP, cyan) imaged between the 32- and 2000-cell stages. Vegetal view. Scale bars, 50 μm. Frame interval of 6 minutes, 7 fps.