Eco-evolutionary dynamics: Novelty as a byproduct of self-organisation (Enrico S Colizzi, 201208)

Talk by Enrico Sandro Colizzi (Origins Center & Leiden University, NL) on 2020-12-08

Abstract
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Throughout 4 billion years of history, evolution has generated novel traits, forms and functions. Novelty often arises from re-purposing old features in a new context: bird feathers originally evolved for thermo-regulation in dinosaurs, the optical properties of the eye are generated by over-expression of common homeostatic proteins, and life itself originated as a side effect of an evolving prebiotic chemistry. In all these cases, the collective eco-evolutionary dynamics of interacting individuals generate a new level of organisation - a collective phenotype. This provides a novel context in which functions can emerge that do not exist at the level of individuals. To study how novelty comes about, I built two models inspired by the RNA world (a hypothetical evolutionary stage that preceded cellular life). In these models, RNA molecules replicate one another, and self-organise into higher-level structures that behave as Darwinian units themselves. RNAs acquire novel functions in the context of these structures. In the first of the two models, I show that molecular parasites behave effectively like mutualists. In the second, a germline-soma division of labour evolves, where soma-like terminal differentiation arises through mutations. In both models, these functions are novel because we do not pre-define them. Therefore, a theory for the evolution of novelty only requires that higher levels of organisation can emerge from local interactions of evolving individuals. I will then show how both these results translate to microbial eco-evolutionary dynamics.