My daughter’s first exposure to the concept of death was when she attended her grandfather’s memorial service when she was 5 years old.

On the way home, my daughter asked softly, will my father leave my sister and me in the future?

I thought about it for a while and tried to give her a tactful and optimistic answer.

But panic and sadness flashed out of her daughter's eyes instantly.

Human beings are helpless in the face of death.

Eternal life has always been our ultimate dream.

Can humans really have eternal life?

The answer is: yes!

And, most of us will live to see this day!

No joke.

Don't be alarmist.

In fact, immortal species are not uncommon.

Life on earth appeared 3.7 billion years ago.

Most of these first life forms were single-celled organisms. One of their characteristics was self-reproduction, so they all lived forever.

So when did death come to the biological world?

One billion years ago, some species began to evolve sexual reproduction.

160 million years ago, flowering plants appeared.

From then on, birth, aging, sickness and death became the norm in the animal and plant world.

Hand-drawn by little friend Helena However, even in the animal world today, there are still some immortal ones.

For example, the jellyfish pictured below is commonly known as the Immortal Jellyfish (scientific name: Turritopsis dohrnii, which lives in the Mediterranean Sea and the Sea of ??Japan).

The immortal jellyfish is so small that you need to borrow a microscope to see it clearly.

They have a magical characteristic: after the larvae turn into adults, once they encounter adversity (hunger, limb damage, etc.), they begin to grow in reverse, losing their tentacles first, and then transforming back into larvae from adults.

Afterwards, it develops into an adult again.

As long as it is not eaten by other animals, it can live in an endless cycle over and over again.

Source: Wikipedia - Immortal Jellyfish are known to live long lives, as are lobsters and sea turtles.

Even at an advanced age, their heart function and body vitality are almost the same as those of "young" lobster turtles, but they are just larger.

Source: National Geographics The mammals to which humans belong are the saddest: all individuals will die!

Don't despair yet.

Even in the human body, some cells are immortal, such as germ cells (cells that produce sperm and eggs).

Human germ cells can continuously replicate themselves, although other cells cannot yet do so, but this is a glimmer of hope.

Because as long as there is a kind of cell that can live forever, it means that we humans still have genes for immortality.

As long as these genes can be found and activated, other cells can be transformed into immortality.

If humans want to achieve immortality, the first step is to understand what exactly causes aging, and then explore ways to solve it.

So, what is the cause of aging?

There are currently two main theories in the scientific community.

One of the theories: The theory of attrition. As we age, our genes are constantly damaged, corroded, and gradually distorted, ultimately causing the aging of our bodies.

Even the self-healing functions within cells will eventually fail.

The "disrepair" is really terrible.

The main advocate of this theory is Aubrey de Grey, chief scientist of the SENS Research Foundation in Cambridge, UK (pictured below).

This dear man was born in 1963, has an immortal spirit, and it seems that the genes in his body are no longer depleted.

Theory 2: Helmet says that every time a cell divides, chromosomes are copied.

Unfortunately, every copy is incomplete.

Less than 1% of the telomeres at both ends of the chromosomes are always missed.

It is said that telomeres are similar to the helmets of chromosomes. They play a protective role and can be cut a few times without any problem.

But I can't stand it one time after another. Generally, after fifty or sixty times, the mitochondria will be damaged.

When the chromosomes lose their helmet protection and are exposed to the knife edge, the cell automatically dies (stops replicating itself).

Our lives have come to an end.

The helmet school is full of talents, and their appearance is not bad.

Three of them also won the 2009 Nobel Prize (from left to right: Elizabeth H. Blackburn, Carol W. Greider and Jack W. Szostak).

Copyright ?The Nobel Foundation 2009Photo: Frida Westholm (To be honest: the common name of the above theory is made up by the author to facilitate understanding and memory. It has not yet been unanimously recognized by the scientific community - and it is expected that it will not be obtained in this life. But the content of the theory does not dare to be messed up

After understanding the main causes of aging, it is only a matter of time to solve them.

Alphabet established Calico in September 2013, specializing in aging and diseases caused by aging.