Conserved variation across scales unveils dialectical relationships of micro- and macroevolution

Abstract

Variation enables short-term evolution (microevolution), but its role in long-term evolution (macroevolution) is debated. Here, we analyzed a dataset of Drosophila wing variation across six levels of biological organization to demonstrate that microevolutionary variation and macroevolutionary divergence are positively correlated at all levels from variation within an individual to 40 million years of macroevolution. Surprisingly, the strongest relationship was between developmental noise and macroevolutionary divergence--levels thought to be the most distant--whereas the relationship between standing genetic variation and population divergence was modest, despite established theoretical predictions. Our results indicate that the congruence of developmental system with long-term history of fluctuation in adaptive peaks creates dialectical relationships between microevolution and macroevolution.