Fig. 4: Prediction and emergence in multicellularity.

One major challenge for synthetic multicellular designs is associated with the lack of predictability that would be in place if the genotype-phenotype map were simple and different scales reducible to lower-level entities. Here we depict the “Waddington demon'': an idealized entity trying to predict higher-scale structures (organs, embryos or organisms) from the observable microscopic dynamics (genes, gene interactions and early developmental states). This cartoon summarizes the difficulties in predicting multicellular complexity, both within developmental biology and in bioengineering. Because of emergent phenomena, such a prediction might be difficult to achieve unless we use the right scale, ignoring the details on the lower levels (drawing by R. Solé).