number of toes is a property of bone structure
eye_socket is bone_structure. toe is anatomical_structure. each has ten_fingers_and_ten_toes we has ten_toes_on_feet humans has 5_toes_on_each_foot we has toes foot has five_toes bone is bone_structure. humans has five_toes_on_each_foot we has five_toes_on_each_foot