Unique features of metazoan gene regulation provide robust cell fate decisions from stochastic components

The developmental patterning of multicellular organisms requires precise control on the scale of microns and chemical sensitivity on the scale of tens of molecules. The molecular system which regulates this careful construction however operates in an environment of substantial stochastic variation. We quantify this variation in the muscle fatedetermination pathway in the early Drosophila embryo and study two evolutionary innovations by which the effects of such variation is minimized to allow very precise tissue specification.