This "graphical abstract" has first been published on the micro-blogging platform twitter on september 8th 2021 to announce the publication of our preprint "Beyond Fitness Decoupling: Tradeoff-breaking during Evolutionary Transitions in Individuality".
An influential view in the study of Evolutionary Transitions in individuality (ETI) is the idea of "fitness decoupling" often associated with the puzzling (at least to me) idea that particles "relinquish" their fitness to the benefit of the collective…However, in the long run, particle and collectives grow at the same rate (provided the population reach a steady state, they all grow proportionally to the dominant eigenvalue of the population projection matrix)…Usually what people mean when they talk about "fitness decoupling" is that there is some kind of tradeoff between traits that differentially influence fitness under different conditions (timesacle, or environement)…… but evolutionary tradeoff are not all set in stone and rare mutations, change in the environement or population structure can sometimes overcome them ! This leads to patterns that are hard to make sense of when focusing on fitness…… This leads to interesting fast-slow dynamics. We applied this to published models such as ratcheting stabilisation of multicellularity (Libby et al. 2016), ecological scaffolding (Black et al. 2020) Overall, times when the new collective context "breaks" the ancestral constraints could be good markers of Evolutionary transitions !
References
Black, A. J., Bourrat, P., & Rainey, P. B. (2020). Ecological scaffolding and the evolution of individuality. Nature Ecology & Evolution, 4, 426–436.
Bourrat, P., Doulcier, G., Rose, C. J., Rainey, P. B., & Hammerschmidt, K. (2021). Beyond Fitness Decoupling: Tradeoff-breaking during Evolutionary Transitions in Individuality (bioRxiv p. 2021.09.01.458526).
Libby, E., Conlin, P. L., Kerr, B., & Ratcliff, W. C. (2016). Stabilizing multicellularity through ratcheting. Philosophical Transactions of the Royal Society B: Biological Sciences, 371, 20150444.
