 Flight feathers are also used by some species in visual displays . Male standard @-@ winged and pennant @-@ winged nightjars have modified P2 primaries ( using the descendant numbering scheme explained above ) which are displayed during their courtship rituals . In the standard @-@ winged nightjar , this modified primary consists of an extremely long shaft with a small " pennant " ( actually a large web of barbules ) at the tip . In the pennant @-@ winged nightjar , the P2 primary is an extremely long ( but otherwise normal ) feather , while P3 , P4 and P5 are successively shorter ; the overall effect is a broadly forked wingtip with a very long plume beyond the lower half of the fork . 
