2022/03/02 by Mark Pagel, Ciara O’Donovan, Andrew Meade · 1 voice · 2 citations
Biochemistry, Genetics and Molecular Biology · Earth and Planetary Sciences · Social Sciences · #Evolution and Genetic Dynamics #Evolution and Paleontology Studies #Evolutionary Game Theory and Cooperation
paper · pdf · doi:10.1038/s41467-022-28595-z
openalex publication_date 2022/03/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Macroevolution posed difficulties for Darwin and later theorists because species' phenotypes frequently change abruptly, or experience long periods of stasis, both counter to the theory of incremental change or gradualism. We introduce a statistical model that accommodates this uneven evolutionary landscape by estimating two kinds of historical change: directional changes that shift the mean phenotype along the branches of a phylogenetic tree, and evolvability changes that alter a clade's ability to explore its trait-space. In mammals, we find that both processes make substantial independent contributions to explaining macroevolution, and are rarely linked. 'Watershed' moments of increased evolvability greatly outnumber reductions in evolutionary potentials, and large or abrupt phenotypic shifts are explicable statistically as biased random walks, allowing macroevolutionary theory to engage with the language and concepts of gradualist microevolution. Our findings recast macroevolutionary phenomena, illustrating the necessity of accounting for a variety of evolutionary processes simultaneously.