Introgression and repeated co-option facilitated the recurrent emergence of C4photosynthesis among close relatives

摘要: The origins of novel traits are often studied using species trees and modeling phenotypes as different states the same character, an approach that cannot always distinguish multiple from fewer followed by reversals. We address this issue studying C4 photosynthesis, adaptation to warm dry conditions, in grass Alloteropsis. dissect trait into its components, show two independent phenotype via anatomical modifications, use distinct sets genes. Further, inference enzyme suggests one groups encompasses transitions a full state common ancestor with intermediate had some biochemical components. Molecular dating genes confirms introgression key components between species, while inheritance all others matches tree. number consequently varies among scenario could not have been inferred analyses tree alone. Our results highlight power individual complex reconstruct trajectories toward adaptations.