You've seen the naked mole rat before. The image of its wrinkled, pink hide and huge buck teeth lingers in your mind. You may have even heard that the naked mole rat is highly resistant to cancer and being deprived of oxygen.
Recent research shows that naked mole rats defy basic laws of mortality (cementing them as the most awesome rodent on planet Earth).
The naked male rat (Heterocephalus glaber) is a rodent that lives underground in the arid regions of East Africa. They are a eusocial animal, like bees and wasps, such that they divide labour and develop special behavioural groups within their societies.
Remarkably, the naked mole rat lives for around 30 years in captivity which, based on its size, is about five times longer than is predicted and around nine times longer than similarly sized rodents. Perhaps more astonishingly, getting old doesn't affect their mortality - as they age, they become no more or less prone to dying.
Of the many thousands of naked mole rats that have died and been autopsied, only a handful of case reports have described tumours in the animal. That's a staggering resistance to cancer, a disease that is considered an 'unavoidable accompanist of aging'.
Spoiler: they don't.
The Gompertzian mortality law (or Gompertz-Makeham law) states that as you get older, you have an exponentially higher risk of dying. Seems relatively straightforward, but until the law was proposed in 1825 there was no formal acknowledgement that you're more likely to die as you get older. We may have known it to be true, but we had never plotted it.
But that's a law that relates to humans.
Using the law with lifespan data from over 3000 naked mole rats, the research team from Calico Life Sciences LLC in the United States demonstrated that the likelihood of mortality did not increase with age - even at 25 times past the naked mole rats age of sexual maturity.
Thus, the thrust of the paper suggests that these animals 'do not age'. While that was rebuked by peer-review, the paper does demonstrate their remarkable resilience to disease and the fact that mortality is not drastically higher in older animals, but remains unchanged over thirty years.
As animals that live far longer than mice, the naked mole rat has been suggested as an alternative rodent for studying disease and aging in humans. Their durability has led to thousands of studies on the creature, in an effort to better understand aging, cancer incidence and ways to stall that dreaded beast - time - from taking its toll on the human body. Studies continue, but the reduction in side effects of metabolic processes, better protein homeostatis and resistance to oxidative damage all enable the wrinkly little thing to live...
As a sidenote: One of my favourite interpretations of the creature is in China Miéville's Railsea, a young adult dystopian novel that is a bit like an updated take on Moby Dick, except the ocean is made of train tracks and the whales are all giant underground moles. It's a great sci-fi read.
Today I Discovered is a daily dose of facts for Lifehacker readers - the weird, wonderful and sometimes worrying. Most of the time, it's just mind-blowing. Let us know if you discovered anything that blew your mind in the comments!