Why has chicken got 5 toes?
Not many birds have more than four toes except chickens of the
Dorking, Faverolle, Houden, Sultan, and Silkie Bantams, all of
which have five toes. In these breeds the extra toe rises above the
base of the hallux and projects upward, this toe never touches the
ground. In the Silkie, the extra toes often lie nearly in the same
plane as the hallux. Some birds have only three toes, while the
ostrich only has two toes.