As a sidenote, Peter Reddien's lab did other studies on planaria (videos are on youtube) and found cells that are supposedly dedicated to map the whole body and

As a sidenote, Peter Reddien's lab did other studies on planaria (videos are on youtube) and found cells that are supposedly dedicated to map the whole body and indicate how differentiation should go in that area (basically one input to the morphogenesis of this animal). It was, after levin's work, another eye openener, as you kinda approach biology as an information problem... everything happening has a piece of data that explains it, we just didn't look everywhere.