The perspective of immortality varies religiously and scientifically, whatever it is, we found out some creatures that live longer naturally. The term is ‘Biological immortality’ and it refers to a decrease in cellular degradation or stable cellular activity after a considerably long living period or sometimes throughout the entire lifecycle. A creature can pull off mortality through gradual death, injury or by infection – this is called Senescence and a few special species achieve negligible senescence.
Presenting the animals that have lived long enough and are still kicking ass –
Lobsters love growing.
They show no sign of ageing and continue to exist for decades together. Although, only few have been observed like this dark red crustacean, probably NYC’s oldest lobster reported to be close to 140 years (see source). While it’s known that lobsters succumb to disease and not by old age, what many don’t know is that it can reproduce till its last breath. In fact, lobsters are more fertile as they age. Trivia: A lobster’s age is calculated by its weight. So, the bigger it gets, the older it is.(source)
Flatworms, especially the Planarians, are promising specimen in the field of ageing research. Planarian flatworms exhibit outstanding regenerative capabilities – an ability that can restore lost tissue or develop into a completely separate organisms when split. The fact that they live with steady telomerase levels (Telomerase is a protein enzyme that aids cell division by enabling continues supply of telomeres) their existence effectively makes them ‘immortal’.(source)
3. Tiny Waterbears
They’re small, adorable and gummy bear like creatures – these factors make them the tough animals on Planet Earth. Water bears or Tardigrades are microscopic 8 –legged water inhabiting organisms that can survive under any condition. From intense space radiation, cruelest low pressure depths, adverse temperature ranges 458 F- 300 F to the harshest deserts, they can thrive with mighty prospects. Waterbears can control and stop metabolism, shed all body water content and remain dehydrated for nearly 10 years – the Tardigrades are here to stay. (source)
A particular species of Jellyfish known as Turritopsis dohrnii uses a transdifferentiation process by which it can indefinitely cycle back to and fro between early polyp stage and mature medusa stage. This way an adult jellyfish can refill its cells by reverting back to a three day polyploidy event thus growing younger again. (source)
5. Turtles and Tortoises
A chosen few vertebrates experience negligible senescence. Researchers have found that the body of turtles and tortoises can persist for several decades without any change in functionality or reproduction capability as long as they stay clear of wounds and diseases. The best example would be Adwaita, one of longest living animals from the family of Aldabra giant tortoise and reaching the age of 255 years. It died in 2006 following a flesh wound in its cracked shell.(source)
Like flatworms, hydra shares the ability to regenerate and prolong life. Found in fresh water, these are multi-cellular and possess radial symmetry. Continuous cell division tramples biological defects while it can prevent telomere loss i.e flow of genetic information from DNA to mRNA thus becoming biologically immortal.(source)