According to the rules of the universe, perhaps the extinction of this world is the mainstream, and the surviving species are only an exception to the extinction process.
Throughout the history of the earth, in the process of the evolution of life on the earth, 99.9% of the ultimate fate of species is to go extinct. In this case, as a member of the earth, human beings will inevitably embark on the road of extinction.
Scientist Carl Sagan famously said, "Extinction is the rule, survival is the exception"
This phrase became one of Carl Sagan's most important quotes. This was said by Sagan in a 1985 lecture, which Ann Druyan compiled into a book in 2006.
这本书名为：《科学经验的多样性:寻找造物主的个人观点》(The different of Scientific Experience: a Personal View of The Search for God)。
Worried about the fate of humanity, it is recommended to join forces with extraterrestrial civilizations to avoid the fate of extinction
Throughout his life, Sagan was arguably deeply concerned about the fate of mankind, not only as an astronomer, but also as an astrophysicist, science fiction writer and popular science writer.
Sagan was involved as an advisor to NASA when it was founded, and Sagan was deeply involved in the U.S. space program and held key positions in the Apollo moon landing program.
Because Sagan is pessimistic about the fate of humanity as a whole, he hopes to find extraterrestrial civilizations, join forces with extraterrestrial civilizations, or seek refuge from the other side to help humanity survive the crisis of extinction. In the last century, Sagan was involved in NASA's important project to find extraterrestrial civilizations.
The metal disc carried in Voyager 1, which everyone is familiar with today, was first conceived by Sagan, who thought that sending a probe with information to the outer solar system would be received by extraterrestrial intelligent life, and then interpreted to establish a connection with humans.
Sagan also helped Dr. Frank Drake design the signal sent by the Arecibo telescope to the M13 globular cluster, which is short but contains a lot of content, hoping that extraterrestrial civilizations will receive this message and reply to Earth.
In addition to the above two, he also believes that human beings should search for extraterrestrial civilizations in a purposeful and planned way, requiring a more scientific way to monitor extraterrestrial radio signals and analyze signals carrying the characteristics of intelligent life.
After years of hard work, in 1982, the prestigious journal Science published a petition for the Search for Extraterrestrial Civilizations (SETI) project, which was signed by 70 scientists, including seven Nobel laureates, and made the controversial project gain social recognition. Eventually, the project was brought to fruition.
Why is extinction the law of nature?
From Sagan's many actions, it can be seen that he is an active supporter of an extraterrestrial civilization and has put it into action. And all these actions are to avoid the fate of human extinction. Why does Sagan think that humanity will eventually become extinct?
On a large scale, the main source of energy in the solar system is the sun, and the fossil energy on the earth can be regarded as the sun's energy reserves. Plants grow on the sun's energy and are then buried in the ground to become fossil energy sources such as coal.
The sun also has a lifespan, and it is currently believed that the sun is the main sequence star, that is, it is in middle age, that is to say, the sun is made of, and at the end of the sun's life, it will become a red giant, and the red giant will expand rapidly, occupying the orbit of the earth, and the earth will also be swallowed by the sun.
And if human beings have not yet flown out of the solar system and are still living on the earth, then the earth and all life on the earth will be swallowed up by the sun.
On a small scale, humanity is also facing crises everywhere: supervolcanic eruptions, nuclear wars, unknown viruses, asteroid impacts, etc., will lead to the extinction of human beings or life on Earth.
These are all objective things, and to a certain extent, they are also things that will happen all the time, and it is difficult to avoid them, and with the current scientific and technological capabilities of human beings, it is difficult to avoid such things from happening.
This has happened once in history, when scientists estimate that humanity was nearly wiped out when the Toba supervolcano erupted on the Indonesian island of Sumatra 750 million years ago, when there were only a few thousand people left on Earth.
So, extinction may really be the norm, and the reason why humans have survived is really an exception. But extinction does not mean destruction, perhaps a new birth.
Extinction means a new birth, and a higher life will be born
Although extinctions are the norm, a very interesting phenomenon has been found throughout the history of the earth, that is, there have been 5 mass extinctions on the earth.
But after each mass extinction, life will develop into higher forms, from the earliest single-celled life, to multicellular life, to mollusks, vertebrates, to mammals, and finally to the emergence of humans.
And among them, every time a creature goes extinct once, the creature will evolve in a more advanced and complex direction. If you look at it on a long-term scale, this creates a large cycle, with peaks and troughs.
Comparing the timelines of the five mass extinctions, an interesting pattern is also found, which is that the further back you go, the shorter the time elapsed.
In the foreseeable future, this cycle will definitely occur, which means that mass extinctions will also occur, and the same extinctions will be accompanied by new births.
When most of Earth's life becomes extinct, a more advanced life will be born, and then the Earth will re-enter a state of prosperity, waiting for the next cycle.
So if human beings really become extinct one day, then they will be replaced by more advanced and intelligent life forms, which can be imagined that this life form may be a biological robot or an artificial intelligence.
Compared with human beings, if artificial intelligence can complete self-replication, theoretically as long as there is enough energy support, it will have unlimited life, then "they" have no lifespan limit, and only they have the ability to travel interstellar when they are restricted by the speed of light.
Perhaps the emergence of human beings is not the final form, but a transitional period in the middle, and the task of human beings is to create a more advanced "human being" and let them evolve into a more complex and advanced life form. This may be the natural law of the universe, "forced" every living form to choose the final direction!
Epilogue:
Carl Sagan also famously paradoxed that he believed in extraterrestrial life, but did not believe that UFOs were the work of extraterrestrial life.
Obviously, he thinks that among those UFOs, it is not necessarily intelligent life, it is very likely to be a biological robot, or a very advanced artificial intelligence, they theoretically have unlimited life, only in this way can it take tens of thousands of years, hundreds of thousands of years to travel between the stars, scattered between the universe, in order to escape the fate of extinction.