CPLC Seminar - Dr. Mikhail Tikhonov to Give on Friday, October 4, 2019

9/26/2019 2:54:50 PM

Modeling the interplay between plastic tradeoffs and evolution in changing environments

Performance tradeoffs are fundamental to evolutionary thinking, but in most models, are simply postulated. This approach is justified for tradeoffs enforced by rigid biophysical or biochemical constraints; unsurprisingly, the best-understood examples are in this class. However, experimental results suggest that many relevant tradeoffs are not rigid, but depend on genetic background and evolutionary history, and can themselves evolve. I will present a simple model capable of capturing the key feedback loop: evolutionary history shapes tradeoff strength, which, in turn, shapes evolutionary future. One consequence of this feedback is that genomes with identical fitness can have different evolutionary properties, shaped by prior environmental exposure. Another is that, generically, the best adaptations to one environment may evolve in another. These results extend previous work relating modularity and “evolvability” to a more general discussion of flexible tradeoff architectures and their impact on evolutionary dynamics.