Hybrid de novo genome assembly of the sexually dimorphic Lady Amherst's pheasant.

Pheasants are an important group of birds, valued for their economic benefit as poultry birds, game birds, and as ornamental species for their plumage. Lady Amherst's pheasant Chrysolophus amherstiae is an ornamental species, valued for their elaborate and beautiful plumage. In this study, we present a high-quality de novo hybrid genome assembly of Chrysolophus amherstiae. Previous attempts to sequence the genome of this species resulted in draft level assemblies, which are not available in the public domain. Using a combination of Illumina short reads and Oxford Nanopore's long-reads we assembled a genome high-quality genome of N50 ~3.9 Mb and near complete BUSCO assessment. We observed a correlation between effective population size and past climatic conditions, with an increase in population size during the warm interglacial periods. We further observed significant fluctuations in genes involved with the immune system and visual perception. Chrysolophus amherstiae are highly dimorphic and significant fluctuations in gene families involved in immune response, visual perception, among others, suggesting a role of mate choice and sexual selection in the evolution and maintenance of exaggerated traits in the males.