Genomic investigation refutes record of most diverged avian hybrid.

Abstract

The most diverged avian hybrid that has been documented (Numida meleagris×Penelope superciliaris) was reported in 1957. This identification has yet to be confirmed, and like most contemporary studies of hybridization, the identification was based on phenotype, which can be misleading. In this study, we sequenced the specimen in question and performed analyses to validate the specimen's parentage. We extracted DNA from the specimen in a dedicated ancient DNA facility and performed whole-genome short-read sequencing. We used BLAST to find Galliformes sequences similar to the hybrid specimen reads. We found that the proportion of BLAST hits mapped overwhelmingly to two species, N. meleagris and Gallus gallus. Additionally, we constructed phylogenies using avian orthologs and parsed the species placed as sister to the hybrid. Again, the hybrid specimen was placed as a sister to N. meleagris and G. gallus. Despite not being a hybrid between N. meleagris and P. superciliaris, the hybrid still represents the most diverged avian hybrid confirmed with genetic data. In addition to correcting the "record" of the most diverged avian hybrid, these findings support recent assertions that morphological and behavioral-based identifications of avian hybrids can be error-prone. Consequently, this study serves as a cautionary tale to researchers of hybridization.