Persistence selection between simulated biogeochemical cycle variants for their distinct effects on the Earth system

Abstract

'Daniel W. McShea' 'Sandra Álvarez-Carretero' 'Timothy M. Lenton' 'Philip C. J. Donoghue'] Title: Significance Darwinian evolution is life’s fundamental sense-making principle and Earth is the only (known) planetary/climatic system capable of supporting life. However, the question of whether Darwinian evolution tends to improve or degrade planetary habitability has been contentious for decades. This is because natural selection is a population-level process that is spatially and temporally separated from the planetary-climatic scales at which habitability can be quantified. Here, we show theoretically how distinct variants of biogeochemical cycles can “compete” by climatic impact “phenotypes,” the effect of which is potentially rendered irreversible by geochemical feedbacks. This “Darwinized” way of looking at biogeochemistry may provide a framework for determining the effect of natural selection on habitability.