Concerted variation in melanogenesis genes underlies plumage patterns in capuchino seedeaters

ESTALLES, CECILIA; TURBEK, SHEELA P.; RODRÍGUEZ-CAJARVILLE, MARÍA J.; SILVEIRA, LUIS FABIO; WAKAMATSU, K; ITO, S; LOVETTE, IRBY J.; TUBARO, PABLO L.; LIJTMAER, DARÍO A.; CAMPAGNA, LEONARDO

Congreso; Evolution 2021; 2021

Society for the Study of Evolution (SSE)

Coloration is central to animal communication; it often governs mate choice, promotes reproductive isolation, and catalyzes speciation. Various studies have identified the genes responsible for particular changes in avian plumage coloration, yet less is known about how coloration patterns (which involve the combination of various color patches) are determined. Here, we study a recent avian radiation, the southern capuchinos, which comprise species with diverse color patterns despite remarkably low genomic divergence. To assess the genomic basis of color differentiation, we performed genome-wide association studies (GWAS) and correlated genotypic differences among species with concentration of melanin pigments (eumelanin and pheomelanin) independently in the feathers of six different color patches. Few genes are associated with color differences among three species that differ solely in their throats, and different genes are responsible for the transitions between different throat colors. Extending our analyses to the whole southern capuchino group, we found that differences in the coloration of each patch are associated with unique combinations of variants in multiple genomic regions. These regions include in most cases genes involved in the melanogenesis pathway, and differences among species were mostly in non-coding, presumably regulatory areas. Some genes are involved in color variation in various patches, but in some cases the SNPs associated with color changes in different patches clustered in different areas in the vicinity of the gene. We suggest that the combination of variants across multiple melanogenesis genes, and likely their interaction, generate the diverse coloration patterns of the southern capuchinos.