Nanoscale millefeuilles produce iridescent bill ornaments in birds.

ABSTRACT: Colors are well studied in bird plumage but not in other integumentary structures. In particular, iridescent colors from structures other than plumage are undescribed in birds. Here, we show that a multilayer of keratin and lipids is sufficient to produce the iridescent bill of Spermophaga haematina. Furthermore, that the male bill is presented to the female under different angles during display provides support for the hypothesis that iridescence evolved in response to sexual selection. This is the first report of an iridescent bill, and only the second instance of iridescence in birds in which melanosomes are not involved. Furthermore, an investigation of museum specimens of an additional 98 species, showed that this evolved once, possibly twice. These results are promising, as th

SUBMITTER: Nicolai MPJ 

PROVIDER: S-EPMC11026107 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature