The Science Behind: Immortality

All animals, including humans, eventually get old and die. Right?

Advances in biology have shown us that immortality isn’t impossible at all. Many organisms remain unaffected by time, and these lucky species can be considered technically immortal.

One such case is of the Hydra, an organism that acquired its name because of this very reason. ‘Immortal’ doesn’t mean the Hydra can’t be killed, but rather that a Hydra in the wild, when left to its own devices, could live forever.

So, if immortality doesn’t mean being unkillable, what does it mean? To scientists, immortality means no signs of aging, disease, and mortality through the passage of time.

The Hydra’s long life is a result of its regenerative ability, which is comparable to a superpower. A full-sized Hydra can grow from just a small clump of living Hydra tissue, making these aquatic animals live for what seems like forever. This lack of aging and resistance to wear and tear is called ‘negligible senescence.’

Senescence is the gradual deterioration that affects every organism with age. More accurately, it is the decline of efficiency in terms of strength, senses, mobility, and resistance to diseases. In humans and most other animals, this deterioration is dramatic and obvious after reaching the prime reproductive age, but there are still animals who naturally do not show signs of senescence.

Of course, these species can be killed, but there is technically no limit to how long a negligibly senescent species may live. So what does this mean for human beings? Is there some way for our cells to imitate the Hydra’s, or of any other ‘immortal’ species?

At SENS, the Strategies for Engineered Negligible Senescence, scientists are proposing ways in which we might be able to harness this superpower (at least to some extent). One of them breaks aging down into nine distinct processes known as hallmarks and suggests that they be targeted and reversed. By giving researchers a way to classify and understand the processes of aging, minimizing senescence may not be out of reach after all.

In the next few decades, it is definitely possible to slow down the effects of time on us, and nature and evolution have already shown us that it is possible to do so. The next step is to use the knowledge we have at our disposal and try to emulate the genetic makeup of these immortal species.