Naked mole-rats can live over 30 years. The oldest recorded mole-rat is currently 39. They are the oldest living rodents, with a lifespan 5 times longer than expected for their body size.
A naked mole-rat’s uniqueness doesn’t stop at their odd appearance. Their long lifespan is one of the many amazing qualities of this rodent. This lifespan is due to multiple biological, social, and environmental factors, all of which we’ll delve into.
How Long Do Naked Mole-Rats Live?
These extraordinary creatures are the oldest living rodents, reaching over 30. The naked mole-rats lifespan ranges between 3–30+ years, with the risk of dying related mainly to environmental factors—such as intraspecies aggression or predator exposure.
The oldest recorded naked mole-rat is an individual at Cincinnati Zoo, who is now 39 years old, and still reproducing. Maximum longevity is unknown, as data collection is continuous.[1]
This astronomical lifespan is five times longer than expected for an animal of its size.[2]
Naked Mole-Rat Wild Lifespan
Naked mole-rats can live over 30 years in the wild. It is theorized that their lifespan may be shorter in the wild than in captivity due to exposure to predators and other colonies of mole-rats.
Tracking the age of wild naked mole-rats is not logistically possible due to the monitoring limitations of their underground habitat. The actual lifespan of wild individuals is not accurately known.
It is expected that they can easily reach the age of 30 like their captive counterparts.[3] Their mortality rate is undoubtedly higher due to exposure to predators and interactions with outsider colonies.
Naked Mole-Rat Captive Lifespan
Naked mole-rats can live over 30 years in captivity. The oldest captive individual is currently 39 years old and still healthy. The average lifespan is likely higher in captivity due to stable food sources and lack of predators.
The maximum lifespan of naked mole-rats in captivity continues to rise year after year as the oldest living mole-rat continues to live happily. As such, the true extent of their lifespan is unknown.
Despite the lack of data, we can conclude that captive mole-rats have a higher average lifespan than wild individuals. Captive settings provide perfectly controlled environments, endless food supplies, and protection from predators and inter-colony interactions.
Why Do Naked Mole-Rats Live So Long?
Naked mole-rats live so long due to their highly efficient cell processes, such as protein synthesis. They are also resistant to cancers and suffer from very little oxidative stress due to low respiration and metabolic rates.
This unexpectedly long lifespan can be attributed to three main reasons:
- Low oxidative stress
- Slow brain development
- Efficient cell processes
Low oxidative stress
In mammals, aging and related issues are linked to cell damage from oxidation.[4] Over time, respiration damages cells and reduces their ability to repair the damage. This can lead to a higher risk of cell abnormalities.
Long-term oxidation has little effect on naked mole-rats as they live in low oxygen environments. This habitat led to the evolution of low respiration and metabolic rates, subsequently reducing oxygen-related stressors.
Slow brain development
Despite their quick sexual maturation, naked mole-rats have prolonged brain development. Their brains continue to grow up to one year after birth and neuron morphology develops for up to 10 years.
This slow development helps the brain retain structure to maintain memory and cognition in their age. It also builds resilience to neurological degenerative diseases.[5]
Efficient cell processes
Naked mole-rats have strange cells. Their ribosomes have three distinctive RNA molecules when mammals usually only have two.
This extra strand reduces the error rate of protein synthesis. Naked mole-rat cells are 40 times[6] less likely to have protein errors than the similar-sized rodent, the mouse.
They also have over-active DNA repair, which far outweighs any cell damage. This makes the naked mole-rat at a much lower risk of cell-related diseases, such as cancer, and aging is almost non-existent.
Factors That Determine the Lifespan of Naked Mole-Rats
The various roles of naked mole-rats determine their individual lifespan. Each role has varying risks and some expose individuals to more predators, while others keep them safe within the colony.
Due to their unique biology, aging does not play a role in the lifespan of the naked mole-rat. Mortality rates do not increase with age as it does with most mammalian species.The chances of dying at the same at one year old as they are at 25 years old.[7]
Risk exposure influences the lifespan of each individual. A naked mole-rat that functions as a soldier may have a lower lifespan due to being at the forefront of aggression from predators or neighboring colonies.
Conversely, a Queen or reproducing male may experience the longest lifespans as they tend to stay at the colony’s center, where they are most protected from predators.
How Do Naked Mole-Rats Usually Die?
Naked mole-rats usually die when attacked by a predator or injured by another mole-rat. Snakes and raptors are their primary predators.
This strange species very rarely die from age-related causes. Naked mole-rats show no signs of aging (e.g. muscle loss) until they reach 28 years old and beyond.[8] They maintain physical fitness and fertility throughout their lives.
The most common cause of death in the wild tends to be predation. Snakes that can access their tunnels and burrows can consume a small naked mole-rat. On the rare occasion that a naked mole-rat breaches the soil surface, they risk being predated by raptors.
Fighting amongst mole-rats can similarly lead to injuries or potentially death. Fighting within colonies is usually happens as a display of dominance and hierarchy climbing. It rarely leads to death.
Naked mole-rats are very hostile towards mole-rats from unfamiliar colonies and often fight. This fighting is more aggressive and has the potential to lead to death.
Naked Mole-Rat Life Cycle
Naked mole-rats are born in large litters that can reach up to 28 individuals. They stay within the nest for the first two weeks. From two weeks on, their eyes open, and they begin to wean. Young adults stay low-ranking for two years, then they may assert dominance to gain reproducing roles or higher ranks.
| Reproduction | Estrus period: 24 hours Gestation: 66–74 days – The queen is the only reproducing female – 1–3 unrelated and physically fit males are her mates |
| Newborn (24 hours) | Litter size: 3-28 Size at birth: 2 grams/0.07 ounces – Incisors emerging – Can walk within hours – Eat Queen’s feces for vital development hormones – Nurse exclusively – Closed eyes |
| Pup (up to 2 weeks) | – Claws develop – Start to nibble on solid food – Eat feces of others – Stay in the nest |
| Juvenile (2–8 weeks) | – Eyes openSuckle less – Start to ween – Can move quickly |
| Young Adult (8 weeks–2 years) | – Assist with food transport & burrow maintenance – Care for the next litter of pups – Remain low ranking – Spar with each other to establish dominance and practice social behaviors |
| Adult (2+ years) | – Move higher in ranks – Reproducing males become dominant – Disperser morphs move out of the colony |
Related: What Do Naked Mole-Rats Eat?
Conclusion
Naked mole-rats can reach extraordinary lifespans of 30+ years. Even at advanced ages, they retain a low mortality rate, and the risk of death does not increase with age, like all other mammals.[9]
This incredible lifespan and many other unique traits have the research potential to fight age-related diseases within genetics.[10]
