Why naked mole-rats will survive the apocalypse
Imagine a post-apocalyptic Earth. Maybe you gloriously envision yourself and a few axe-wielding mates escaping to the wilderness. Or perhaps, like many, you consider cockroaches as heirs of the Earth. Personally, I believe there is one creature capable of surviving the end of times — the naked mole-rat.
In an apocalyptic event– no one will come close to the bunker mastery of the naked mole-rat. Naked mole-rats are rodents that live in colonies ranging from 20-300 individuals. They create incredibly complex burrows underground that span up to 5 kilometers in total length.
Unlike other mammals they are eusocial, with one reproducing queen and a colony of sterile workers (like ants and bees).
Native to East Africa, naked mole-rats are masters at surviving a life spent underground.
But how do they breathe?
Underground there is very little oxygen, so naked mole rats have an highly altered metabolism to reduce the amount they need.
Their lungs are very small, and the hemoglobin molecules in their blood– responsible for carrying oxygen around the body– have a much higher affinity for oxygen than lab mice. Their hemoglobin can more quickly pick up oxygen to move around the body, wasting less of the limited supply.The naked mole-rat also slows its metabolism and breathing rate, further decreasing the amount of food and air needed.
The low levels of oxygen pose another risk to your everyday mammal. The pain you feel when holding your breath is not a result of lack of oxygen, but because of a build up of carbon dioxide. Excess carbon dioxide causes a build-up of acid in the blood stream.
Naked mole-rats have evolved to overcome this by lacking the ability to feel pain even when exposed to capsaicin (the molecule that makes chili burn) and acid. Naked mole-rats lack a molecule called substance P which sends pain signals to the brain in mammals. When injected with substance P, naked mole rats respond to capsaicin but not acid. They don’t feel pain caused by acid which helps them cope with high levels of carbon dioxide underground.
They (almost) live forever
Naked mole-rats can conserve energy like crazy, hardly have to breathe and feel no pain. But their biggest medical curiosity lies in their lack of cancer. A few factors make naked mole-rats highly resistant to cancer. In fact, cancer has only ever been documented twice in naked mole-rats.
The first is because they have a special combination of “over-crowding genes”. Tumours are caused by an overgrowth of cells, which fail to stop dividing. These over-crowding genes stop cells from dividing when they are at a high density, preventing the formation of tumours.
Naked mole-rats also have highly precise and error-free ribosomes— structures that make proteins in the body. This lowers the chance of mutations and hence the risk of cancer. Even more, naked-mole rats have extremely large forms of the carbohydrate hyaluronan. Hyaluronan is used as a marker for testing for prostate and breast cancers and is up to 5 times larger in size in naked mole-rats than cancer-prone lab rats.
As a result of a slow metabolism and lack of cancer, naked mole-rats have a far longer lifespan compared to other rodents. While the common brown rat lives a meagre 2 years, the naked mole-rat can live up to 30.
As the imminent apocalypse approaches, it is time we start considering our rodent successors.