10 Things You Didn't Know About Naked Mole-Rats

Naked mole-rats are pink, nearly hairless rodents from East Africa

Smithsonian’s National Zoo & Conservation Biology Institute

Naked mole-rats aren't moles or rats, and they actually aren't even naked, despite what their name suggests. They are burrowing, bucktoothed rodents that look like miniature, skinny walruses, native to East Africa, and they have become a major source of fascination for scientists. Sand puppies, as they're also called, live a special lifestyle that has forced them to adapt in various ways. These adaptations give humans insight into their own health and wellbeing, from pain relief to cancer research to aging. Naked mole-rats represent a treasure trove of medical possibilities. Here are a few facts about these captivating (if a little weird-looking) creatures.

1. Naked Mole-Rats Are Eusocial

Naked mole-rats operate on an insect-centric royal system

Smithsonian’s National Zoo & Conservation Biology Institute

Similar to termites, ants, and other insects, naked mole-rats exhibit eusociality. There's a queen, one to three males with whom she reproduces, and the rest are either "soldiers," which protect the nests from snakes and other naked mole-rats; foragers, which gather food; or tunnelers. There could be up to 300 in just one colony. Besides the queen, females aren't physically capable of reproducing. Naked mole-rats are the first mammals to exhibit this structure.

2. Their Nests Are Big, But You May Not Even Notice Them

Naked mole-rats in their nest

Dr. Chris Faulkes / Queen Mary University of London

Apart from a volcano-like hole that serves as both its entrance and exit, an underground mole-rat burrow is typically barely visible. There could be several miles of tunnels and chambers, with highly organized caverns—including a burrow just for feces—under your feet and you'd never even notice. When the burrow is full, they simply close it up and build a new one.

3. They Do Have Hair, and It Serves a Special Purpose

Naked mole-rats have about 100 hairs on their bodies

Field Museum

According to the San Diego Zoo, sand puppies are not entirely hairless (as their name wrongly suggests). They have about 100 fine hairs all over their bodies that act as whiskers, helping the mole-rats to sense what's around them. The hair between their toes serves a different purpose—it helps sweep soil as they burrow underground.

4. They Don't Get Closer to Death as They Age

Naked mole-rat has a snack

Smithsonian’s National Zoo & Conservation Biology Institute

A 2018 study published in eLife found that, unlike other mammals, naked mole-rats' risk of mortality doesn't increase as they age. Humans, in comparison, take the opposite approach, doubling their risk of death every year after the age of 30. For this anomalous mammal, however, the risk of death at age 6 months—around the time they reach sexual maturity—is one in 10,000. That number doesn't increase as they get older and, in fact, it can even decrease. The naked mole-rate can live to be 30.

5. They've Been Known to Kidnap Other Mole Babies

Naked mole-rat and babies

Bioparc Valencia

The co-op lifestyle doesn't always bode well for mole-rat offspring. The queen can birth up to 30 pups in a litter, then convince her workers to care for them by feeding them her hormone-laced feces. In past studies, worker mole-rats have stolen the pups from the queen and put them to work in another, neighboring colony. Their tendency to care for young that aren't their own is an example of alloparenting.

6. Certain Proteins Help Them Stay Healthy

Naked mole-rat eats near a carrot

John Trainor / Wikimedia Commons

In a regular digestive process, proteins are damaged and then recycled to form new proteins. Those that aren't discarded can become toxic to other cells, leading to various aging-related diseases. Naked mole-rats, however, are much more efficient at recycling their proteins. Their bodies tag fewer proteins for recycling because fewer proteins actually need it, according to a study published in Proceedings of the National Academy of Sciences of the United States of America (PNAS). This protein stability may be a clue to their longevity.

7. Naked Mole-Rats May Be Cancer-Free Thanks to One Gene

Naked mole-rats have a gene that prevents them from getting cancer

Smithsonian’s National Zoo & Conservation Biology Institute

Another 2009 study published in PNAS found that naked mole-rats have a gene, "p16," that prevents cells from reproducing when they get too bunched up. This fail-proof gene prevents them from getting cancer, which is caused by aggressive cell growth. Given their long lifespans (and the fact that longer lifespans can often mean more cell growth), this discovery could help humans combat cancer, too.

8. Their Acid Insensitivity Is Aiding Pharmaceutical Research

Naked mole-rat in a tunnel

Neil Bromhall / Shutterstock

Because they spend so much time in cramped tunnels—where an excess of exhaled carbon dioxide leads to a buildup of acid levels—naked mole-rats have had to adapt to dire conditions. Early researchers expected to find their neurons without acid receptors, but what they found instead was that the sodium channel that would normally send pain signals to the brain becomes blocked when acid molecules bind with their pain sensory receptors. This has been a pivotal discovery in the advancement of human painkillers.

9. Who Needs Oxygen? Not the Naked Mole Rat

Naked mole-rats can go without oxygen for 18 minutes

Zoo Atlanta

Low-oxygen environments are deadly for most organisms, but these critters can live without air for 18 minutes, or with little air for up to five hours. They basically turn into plants. When there's limited oxygen, their system pumps fructose into their bloodstreams, then into their brains. Without this ability, surviving in burrows where oxygen is at a premium would be next to impossible.

10. Their Big Teeth Are Vital to Their Survival

A naked mole rat munches on food

Trisha M Shears / Wikimedia Commons

Naked mole-rats feast on tubers and roots, which requires strong chompers. According to the San Diego Zoo, those two prominent front teeth continue to grow, but are kept at a reasonable length thanks to constant filing. They're also handy for tunneling, and their mouths remain soil-free because their lips seal behind their teeth. But the most exceptional feat? They can move each tooth individually, like chopsticks, to grasp things.