As vulnerable as naked mole rats seem, researchers now find the hairless, bucktoothed rodents are invulnerable to the pain of acid and the sting of chili peppers.

• 裸鼹鼠看上去似乎象它的外表一样脆弱,研究员目前发现这种无毛獠牙啮齿目动物对酸和辣椒的刺激刀枪不入的。