The ring radius and the number of ringsincrease with fork length and are considered to be formed with the growth of fish,therefore,the vertebra is thought to be the most effective aging structure.

• 脊椎骨上轮纹之位置具有规则性存在，而且轮纹会随著鱼体的成长而形成，所以脊椎骨为一有效之年龄形质。