Naked mole-rats live together in tight, enclosed burrows in African soil, where poor ventilation results in a buildup of carbon dioxide, making the environment extremely acidic. Such conditions would be intolerable to most mammals. But according to a study was published online this week on PLOS ONE, not only do mole-rats survive in such conditions, they seem entirely unaffected, staying in acidic conditions much longer than rats, mice, or a closely related mole-rat species that is not normally exposed to such acidity.
When placed in a system of cages with areas of acidic air and areas of clean air, most rodents actively avoided the acidic fumes. This response is regulated by a collection of nerves in the brainstem called the trigeminal nucleus, which is activated by specialized nerve fibers in the mole-rat’s nose and results in mucus secretion, rubbing of the nose—suggesting that the animals are in pain—and withdrawal from ...
