Showing posts with label unusual. Show all posts
Showing posts with label unusual. Show all posts

Tuesday 31 March 2020

Living in the dark, ugly beyond words but resilient


The naked mole-rat is the size of a mouse and is, one has to admit exceptionally ugly. It is a eusocial animal.  This term describes creatures who live in large colonies with a single breeding female who keeps her subordinates sexually immature. These rats are found in the hot arid regions of Kenya, Somalia and Ethiopia and live in dark underground tunnels their entire lives. 

They have a dreadful sort of caste system with ‘infrequent workers’ who have considerably larger bodyweight than the ‘frequent workers’. Frequent workers as well as being smaller do twice as much work as infrequent workers. Then, there is a further category ‘the non-workers’ who are the largest mole rats in the colony, bar the Queen. The non-worker group, true to their name, hardly ever dig or transport material. Their role is partly reproductive as they mate with the breeding queen but they also take care of the young. 

The frequent workers are so busy digging and transporting soil and carrying food to the communal nest that they have barely enough time to eat. In fact, as a result, the naked mole-rat has a metabolism that resembles that of an animal on a calorie-restricted diet. This kind of diet is associated with longevity and indeed one of its surprising characteristics is its unusually long lifespan.

Rodents, such as mice of a similar size, rarely last beyond 4 or 5 years but these naked mole-rats live over three decades and are still healthy and fertile in their 30s.  In fact, they actually don’t appear to age at all. Their heart functions, bone density, muscle mass and metabolism all stay healthy despite the passing decades. They have in addition, exceptional resistance to developing cancer. Having observed large numbers of naked mole-rat colonies over many years we have been hard put to find any instances of cancer. No wonder then, the biology of the naked mole-rat is generating an unusual amount of interest in the fight against cancer in humans.

These animals live in stifling tunnels in complete darkness with very low oxygen levels. They dig in soil rich in toxic heavy metals and they eat poisonous tubers and suffer no adverse consequences. But this is the least of their special skills. When their cells are exposed to UV light they suffer no consequences. Even high doses of chemotherapy drugs have no effect on these tough guys. Such resistance to toxins is probably related to why they don’t age. The trick seems to be they have learnt to cope with exceptional levels of cellular damage from a very young age. Instead of avoiding such damage, they have cultivated an unusual ability to stop damaged cells from dividing and multiplying. They put their focus on preventing the multiplication of mutant cells.

They are creatures of the dark who tend to eat their own shit at times. They live in oxygen-deprived stuffy tunnels.  In fact, these guys can survive for five hours in air that contains only 5% oxygen. Perversely, during that oxygen-deprived time, they don’t show any significant signs of distress and continue with their normal activities. Consuming poison and surrounded by toxins these guys stay ever young. They literally are, as tough as old boots. They may look weird but you’ve got to admire their tenacity. The naked mole-rat can even survive 18 minutes without any oxygen at all. It has to be the real definition of a tough guy.

We have a lot to learn from the naked mole-rat. They cope with dark days and their skin does not feel pain.  For humans our risk of dying doubles every eight years after the age of 40. The naked mole-rat experiences no increased risk of dying with age. They may look repulsive but in some ways, they are real superheroes!

At a time, when we are living through difficult days watching humanity suffer from the Covid 19 virus many of us will have to draw on our own resilience and toughness.  Holding our breath at the loss of life and suffering unfolding.  Finding superheroes, in our communities who fight to preserve life in dark and scary days.