Supplementary Figure 2: Alignment of contraction expansion maps of 9 embryos.

This result of averaging of the contraction expansion maps of nine embryos. The embryos were aligned and synchronised according to developmental time as described in detail in methods. The main features such as the initiation of contraction in the central mesendoderm followed by outward expansion of this contraction domain followed by streak formation and deformation of the area in front of the streak appear highly conserved. The black scale bar in the first image is 200 μm.