Structural stability can shape biological evolution

We analyze a model of biological evolution recently introduced in the literature and show that punctuated equilibrium and power-law behavior arise because of the differential structural stability of the mapping between genotype and phenotype that characterizes the model. Structural stability is a feature of biological organisms that had been introduced by biologists long ago, but never modelled until now, as far as we know. This model can be regarded as an alternative to those models that explain both the power-law behavior and the punctuated equilibrium of extinction curves by recourse to self-organized criticality (SOC).