This image shows the DSLM set-up. The two cameras used for detection are clearly visible. The team used the set-up to study the three-dimensional pattern of cell divisions during early development. "Initially, these patterns are very symmetrical," Keller told optics.org. "However, the digital embryo shows that this radial symmetry is broken in the 512 cell stage."

Keller and colleagues were also able to study the formation of germ layers. "Formation of the three germ layers is a crucial step in development, since these later on give rise to different tissues and organs, such as heart, muscles, skin or brain," explained Keller. "The digital embryo reconstruction allowed us to quantitatively follow the cell movements during germ layer formation and this revealed that these movements actually happen differently than previously thought. In our paper we provide a new model of germ layer formation, which summarizes our observations."