The Red Junglefowl juniors preening their feathers in a tree, in a continuation of a series of videos of Red Junglefowls in Bishan Singapore. This is a ritual by birds to maintain their feathers. Notice the half closed nictitating membrane covering the eyes during the preening. This is a transparent inner eyelid in birds, reptiles, and some mammals that closes to protect and moisten the eye. Also called third eyelid.