Here is an interesting video about a Black Sicklebill displaying.
Black Sicklebills are elegant, slender birds with long bills and tails. But that all changes when a female comes by. The male transforms into a horizontal comet shape on his display perch. He doesn’t use his wings to do this; he uses flank feathers. The comet shape is accentuated by a narrow blue band of iridescence created when those flank feathers line up precisely. Filmed and photographed by Tim Laman and Eric Liner. [YouTube]
“The black sicklebill (Epimachus fastosus) is a large bird-of-paradise of midmountain forests of New Guinea.
The sicklebill’s diet consists mainly of fruits and arthropods. The male of the species performs a horizontal courtship display with the pectoral plumes raised around its head.
The male has black plumage with iridescent green, blue and purple scale-like feathers, red irises, bright yellow mouth, long curved black bill, huge sabre-shaped tail and large erectile fan-like plumes on the sides of its breast. The female is smaller than the male, with reddish brown plumage, brown irises, and buff below. Reaching up to 110 cm in length, the male black sicklebill is the longest member of Paradisaeidae, though the curl-crested manucode has a larger body.” [Wikipedia with editing]
‘Call to Me, and I will answer you, and show you great and mighty things, which you do not know.’ (Jeremiah 33:3 NKJV)