New study reveals the genetic history – and possible future – of four Asian hornbills

Researchers from India have created reference genomes for four endangered species of Asian hornbills, according to a recent study. The scientists from the Nature Conservation Foundation in Mysore and the CSIR–Centre for Cellular and Molecular Biology in Hyderabad sequenced the high-quality genomes of the great hornbill, rufous-necked hornbill, Malabar pied hornbill, and wreathed hornbill.

Prior to this study, only two of the 32 Asian hornbill species had their whole-genome information available. The research team employed two types of genetic sequencing to construct genetic maps for each species, utilizing both short- and long-read DNA sequencing to reduce errors. Pooja Pawar, the corresponding author and a doctoral researcher at NCF, explained that genomic tools enable scientists to investigate the species' histories across the region and over time.

By employing statistical modeling, the team traced changes in hornbill populations throughout history and found that climatic instability during the Pleistocene epoch (2.5 million to 11,000 years ago) led to reduced effective population sizes for all four species. The widely distributed wreathed hornbill had a larger effective population size compared to the other three species.