Every animal has its unique characteristics and traits. But the mole rat is a particularly unusual creature. I think, in many ways, they look like teeny-tiny Sharpei puppies, but with buck teeth. The rat's body is adapted for a life spent underground. Those protruding teeth are used for digging and their lips seal behind their teeth to prevent the rate from ingesting the dirt while they dig. And while this little guy isn't blind, their eyes are small with poor visual acuity. Their legs are short and thin but they can move forward and backward with the same ease. Mole rats aren't totally bald. They have very little hair, though, and they lack a layer of insulating fat below the skin. They average in length from only three to four inches (8-10 cm) and weigh a whopping 1.1 to 1.2 ounces (30-35 g). They love togetherness and live in colonies of 200 to 300 individuals in the dry grasslands area of East Africa. As a rule, mammals are warm-blooded, meaning they are thermoregulators able to maintain body temperature despite external conditions. But while the naked mole rat is considered a mammal, they are cold-blooded thermoconformers. "When a naked mole rat is too hot, it moves to a deeper, cooler part of its burrow. When it's too cold, the rat either moves to a sun-warmed location or huddles with its pals."
While humans start to lose brain cells after only 60 seconds without oxygen and will suffer permanent brain damage after three minutes without it, the little mole rat can survive 18 minutes in an "oxygen-free environment without suffering any harm." They also live in an environment that is 80% carbon dioxide and 20% oxygen. Humans would die from carbon monoxide poisoning under those conditions.
But here is where these little critters get really interesting...and how studying them might show scientists how humans can live longer. The naked mole rat doesn't die from old age.
While the average garden-variety rat can live up to three years, the naked mole rat lives 32 years! "Both naked mole rats and humans have DNA repair pathways not present in mice. Another reason mole rats may outlive mice is that of their lower metabolic rate."
Don't get me wrong. Naked mole rats aren't immortal. They just don't die from old age. They die from predators and from illness. "However, mole rat aging does not adhere to the Gompertz law describing aging in mammals. Research into naked mole rat longevity may help scientists unravel the mystery of the aging process."
Add to that fact, the naked mole rat resistance to cancerous tumors, and you have a combination of traits worth taking a second look at. And while they do get sick and die from illnesses, they are highly resistant to tumors. "The only malignancies discovered in naked mole rats were in captive-born individuals, which lived in a much more oxygenated environment than rats in the wild." Want even more mole rat weirdness?
Mole rats neither itch nor feel pain. Their skin lacks a neurotransmitter called "substance P" that is needed to send pain signals to the brain. Scientists believe this might be an adaptation to living in poorly ventilated species, where high levels of carbon dioxide cause acid to build up in tissues. Further, the rats don't feel temperature-related discomfort.
Whether or not the naked mole rat offers human scientists a glimpse into what might cause immortality, these weird little mammals are extremely fascinating to study.
I hope you've enjoyed learning about the Heterocephalus glaber, otherwise known as the naked mole rat. Please join me back here tomorrow for a look at kites on National Kite Flying Day. Until then, I wish you PEACE.