The naked mole-rat does not regulate its body temperature in typical mammalian fashion. As of 2017, it was not known how the naked mole-rat survives acidosis without tissue damage. This pathway is not inhibited by acidosis as happens with glycolysis of glucose. When deprived of oxygen, the animal uses fructose in its anaerobic glycolysis, producing lactic acid. During the anoxic period it loses consciousness, its heart rate drops from about 200 to 50 beats per minute, and breathing stops apart from sporadic breathing attempts. In zero-oxygen atmosphere, it can survive 18 minutes apparently without suffering any harm (but none survived a test of 30 minutes). It can live in an atmosphere of 80% COĢ and 20% oxygen. The naked mole-rat survives for at least 5 hours in air that contains only 5% oxygen it does not show any significant signs of distress and continues normal activity. In response to long periods of hunger, its metabolic rate can be reduced by up to 25 percent. It has a very low respiration and metabolic rate for an animal of its size, about 70% that of a mouse, thus using oxygen minimally. It has underdeveloped lungs and its hemoglobin has a high affinity for oxygen, increasing the efficiency of oxygen uptake.
The naked mole-rat is well adapted to the limited availability of oxygen within the tunnels of its typical habitat. They lack an insulating layer in the skin. They have little hair (hence the common name) and wrinkled pink or yellowish skin. About a quarter of their musculature is used in the closing of their jaws while they dig. Their large, protruding teeth are used to dig and their lips are sealed just behind the teeth, preventing soil from filling their mouths while digging. Their legs are thin and short however, they are highly adept at moving underground and can move backward as fast as they can move forward. Their eyes are quite small, and their visual acuity is poor. They are well adapted to their underground existence. Queens are larger and may weigh well over 50 grams (1.8 oz), the largest reaching 80 grams (2.8 oz). Typical individuals are 8 to 10 cm (3 to 4 in) long and weigh 30 to 35 grams (1.1 to 1.2 oz). While formerly considered to belong to the same family as other African mole-rats, Bathyergidae, more recent investigation places it in a separate family, Heterocephalidae. It is also remarkable for its longevity and its resistance to cancer and oxygen deprivation. The naked mole-rat lacks pain sensitivity in its skin, and has very low metabolic and respiratory rates. The naked mole-rat exhibits a highly unusual set of physiological and behavioral traits that allow it to thrive in a harsh underground environment most notably its being the only mammalian thermoconformer with an almost entirely ectothermic (cold-blooded) form of body temperature regulation, as well as exhibiting a complex social structure split between reproductive and non-reproductive castes, making it and the closely related Damaraland mole-rat ( Fukomys damarensis) the only widely recognized examples of eusociality (the highest classification of sociality) in mammals. It is closely related to the blesmols and is the only species in the genus Heterocephalus.
The naked mole-rat ( Heterocephalus glaber), also known as the sand puppy, is a burrowing rodent native to the Horn of Africa and parts of Kenya, notably in Somali regions.
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