Given the strictly subterranean existence of the naked mole-rat (Heterocephalus glaber), it is not surprising that naked mole-rats have evolved a set of characteristics highly suited to life in dark, dank burrows. Here are a few:
Blood: Naked mole-rats have a greater number of red blood cells per unit volume, and the hemoglobin in the red blood cells has a higher affinity for oxygen than that of most other mammals, so their blood is better at capturing what little oxygen there is.
Ears: No external ears, only openings in the sides of the head
Eyes: Very small eyes, which the animals often don’t bother to open, that are only able to distinguish light from dark
Metabolism: Their mass-specific metabolic rate is about 70 percent that of other rodents, meaning their tissues use oxygen at a slower...