The Time-Turning Jellyfish That Cheats Death
Nothing lasts forever.
A human has an average lifespan of 73 years; a dog, 10 years; and a butterfly, only 21 days. But somewhere within our planet's vast oceans, one tiny jellyfish, the Turritopsis dohrnii, more commonly known as the “immortal jellyfish”, stands out as a biological marvel with a potential lifespan of forever.
T. dohrnii is a species of jellyfish that measures only 4.5 millimeters in diameter, yet it possesses an amazing ability that allows it to defy the natural aging process and essentially live forever. So what is this jellyfish’s secret to eternal youth, and could humans ever harness it? Should humans ever harness it?
To fully appreciate the abilities of the immortal jellyfish, we must first understand the life cycle of a regular jellyfish. This begins with a planula larva that settles onto a surface and develops into a feeding polyp, which can clone itself to form a small colony. When a section of the polyp matures, it breaks off and becomes a free-swimming medusa that can reproduce sexually.
In most jellyfish, the medusa stage is the final phase of the life cycle, after which the jellyfish usually ages and dies. However, T. dohrnii has the extraordinary ability to return to its polyp phase when faced with death.
The key to the immortal jellyfish’s ability lies in the process called transdifferentiation, which is when a specialized cell permanently transforms into an immature cell, which can grow and develop again completely from scratch. Essentially, it’s when a cell with a specific job transitions into another type of job.
When subjected to high levels of stress, such as physical damage, starvation, or even natural aging, the jellyfish can initiate transdifferentiation, effectively resetting its cells to a younger state.
The medusa shrinks, retracts its tentacles, and becomes a blobby structure called a cyst, which settles onto a solid surface. Within three days, the cyst starts growing back into a polyp, starting the cycle anew.
When the power of T. dohrnii was discovered, scientists scrambled to uncover how this jellyfish defied death and aging. If they can unravel the mechanisms behind its transdifferentiation, it could lead to breakthroughs in human aging research. For example, it may be possible to develop therapies where transdifferentiation is induced in aging cells, potentially delaying or reversing human aging.
However, while the prospect of reversing aging holds promise, it also carries significant consequences. If humans could live significantly longer lives, competition for resources would intensify, further exacerbating issues such as poverty and environmental degradation. Furthermore, life’s impermanence serves as a stark reminder of man’s mortality and encourages many to live meaningful and purposeful lives. If we conquered aging, it could fundamentally alter our perspective on life’s value. If science could grant us immortality, would we be wise enough to handle it?
Sources:
https://www.sciencefocus.com/nature/whats-the-longest-a-butterfly-can-live-for
https://www.petmd.com/dog/care/how-long-do-dogs-live
https://www.macrotrends.net/global-metrics/countries/WLD/world/life-expectancy