Time-lapse confocal imaging of a control Tg(flk:GFP) embryo. This video shows time-lapse spinning disk confocal imaging of the AGM region of an flk1:GFP embryo between 32 and 44 hpf (1 frame/5 min). Numbers appear in the video to point to endothelial cells that undergo EHT. Select frames of the video are shown in Fig. 5 A.