An adult male Siberian tiger has a hind leg thickness of 50 cm and a front leg thickness of 20 to 30 cm. Tiger's leg bone has obvious ribs, the upper segment is a single bone, and the lower segment is composed of two bones. There is a flat hole near the bone ring at the lower end of the upper limb, commonly known as phoenix eye. The lower two bones stand almost side by side, slightly flat and twisted, but one is very long.