Genomic signatures of the evolution of a diurnal lifestyle in Strigiformes

Abstract

Understanding the targets of selection associated with changes in behavioral traits represents an important challenge of current evolutionary research. Owls (Strigiformes) are a diverse group of birds, most of which are considered nocturnal raptors. However, a few owl species independently adopted a diurnal lifestyle in their recent evolutionary history. We searched for signals of accelerated rates of evolution associated with a diurnal lifestyle using a genome-wide comparative approach. We estimated substitution rates in coding and non-coding conserved regions of the genome of seven owl species, including three diurnal species. Substitution rates of the non-coding elements were more accelerated than those of protein-coding genes. We identified new, owl-specific conserved non-coding elements as candidates of parallel evolution during the emergence of diurnality in owls. Our results shed light on the molecular basis of adaptation to a new niche and highlight the importance of regulatory elements for evolutionary changes in behavior. These elements were often involved in the neuronal development of the brain.

PhyloAcc-GT: A Bayesian Method for Inferring Patterns of Substitution Rate Shifts on Targeted Lineages Accounting for Gene Tree Discordance

“…In contrast, regions of the genome exhibiting accelerated substitution rates may have undergone positive directional selection or relaxation of purifying selection. Identifying these regions in a phylogenetic framework can therefore provide insight into the selective pressures acting on them and may enable the identification of potential changes in function in lineages of interest ( Sackton et al 2019 ; Kowalczyk et al 2020 ; Espindola-Hernandez et al 2022 ; Pollard et al 2006 ).…”

PhyloAcc-GT: A Bayesian method for inferring patterns of substitution rate shifts and associations with binary traits under gene tree discordance

“…Furthermore, regions of the genome that exhibit accelerated substitution rates may have undergone positive directional selection or relaxation of purifying selection. Identifying these regions with accelerated substitution rates in a phylogenetic framework can therefore provide insight into the selective pressures acting on them and may enable the identification of potential changes in function in lineages of interest (Sackton et al, 2019; Espindola-Hernandez et al, 2022; Kowalczyk et al, 2020; Pollard et al, 2006).…”