Re-assessing the phylogenetic status and evolutionary relationship of Forest Owlet using genomic data

Abstract

Phylogenetic relationships are often challenging to resolve in recent/younger lineage when only a few loci are used. Ultra Conserved Elements (UCE) are highly conserved regions across taxa that help resolve shallow and deep divergences. We utilized UCEs harvested from whole genomes to assess the phylogenetic position and taxonomic affiliation of an endangered endemic owlet in the family Strigidae - the Forest Owlet Athene blewitti. The taxonomic placement of this species has been revised multiple times. A multigene study attempted to address the question but showed a discrepancy across datasets in its placement of the species within genus Athene. We assembled a dataset of 5018 nuclear UCE loci with increased taxon sampling. Forest Owlet was found to be an early split from the Athene clade but sister to other Athene; and consistent across three approaches - maximum likelihood, bayesian, and the multispecies coalescence. Divergence dating using fossil calibrations suggest that the Athene lineage split from its ancestor about 7.6Mya, and the Forest Owlet diverged about 5.2Mya, consistent with previous multigene approaches. Despite osteological differences from other Athene, we suggest the placement of the Forest Owlet as a member of the Athene to emphasize its evolutionary relationship. Graphical Abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY HIGHLIGHTSO_LIPhylogenomics using genome-wide nuclear markers yielded a well-supported topology for Athene and Glaucidium lineages. C_LIO_LIThree different methods of phylogenetic tree construction showed that Forest Owlet is an early split from all other Athene species. C_LIO_LIDivergence dating in the bayesian framework puts the Forest Owlet age between 5.0my to 5.5my. C_LI