Animals that may be immortal
By Zhang Hao
["china"]
Some animals and plants are so blessed that they may live forever if they can avoid catastrophic changes in the environment, disease or being killed or destroyed by an external force. The problem of aging which is closely connected with death for most life on Earth may not be the case for some other animals and plants, all thanks to their unique biological mechanism.
Turritopsis dohrnii
Also know as immortal jellyfish, this creature is able to turn our dreamed time machine into reality. In other words, it can reverse its age and transfer from an adult to a younger body in case of sickness or life-threatening injuries. Thus, a grown-up jellyfish goes back to polyp. The process can be completed in three days and the cells magically reverse into a younger state and grows into adulthood again. This process can be repeated again and again.
Turritopsis medusa from Florida, America. /VCG Photo

Turritopsis medusa from Florida, America. /VCG Photo

American lobster
Two interesting features about this lobster: one, the bigger a lobster is, the older it is. Two, they commonly die of diseases instead of old age. They simply keep growing and reproducing until their number is up. Not enough evidence has been discovered to prove their immortality, but the lobsters are indeed able to grow a new limb if the old one is damaged. A 1998 study discovered that the lobster is equipped in a different way to keep the cells always young, consequently, making their life spans exceptional. 
American lobster illustration by Sherman Foote Denton, 1902. /VCG Photo

American lobster illustration by Sherman Foote Denton, 1902. /VCG Photo

Flatworm
What fascinated scientists about the flatworm is their exceptional regenerating ability. After being split into two halves, the flatworm can regenerate into two separate worms.
Moreover, scientists who have studied flatworms, found that the worms can grow new muscles, skins, guts, and brain over and over again, they are also able to keep their cells forever young. Telomeres, tips of chromosomes, are regarded as an indicator of aging speed. Normally, it becomes shorter each time a cell divides, thus weakening the ability of cell replication. However, these worms magic is to maintain the length of the telomeres so that they retain the ability to replace old cells by new cells, indefinitely. In other words, the combination of their extraordinary regenerating skills and the magic of remaining young will theoretically make them live forever. Yet, however exciting the discovery is, it may still take some time to find out what exactly blesses the secret of being young forever.
(Top image via VCG.)
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