Overview
Counting from the oldest known Sumerian civilization, human civilization has developed for more than 7,000 years. has only lived for a hundred years, which is already a long period of time in front of individual human beings.
Looking at it vertically, the history of more than 7,000 years is so short in the 4.5 billion years of the earth's life. To make an intuitive metaphor, if the 4.5 billion-year history of the earth is condensed into one day, then humans may only occupy less than 1 minute.
If this is the case, then before the emergence of human civilization, it is entirely possible that other civilizations existed on the earth, at least for enough time.
Not to mention the academic debate over the existence of prehistoric civilization , to take a step back, even if prehistoric civilization once really existed, it has long since perished completely.
If humans, like prehistoric intelligent creatures, have disappeared from the earth for tens of thousands of years, or even billions of years, what traces can prove that humans once existed?
If human beings become extinct
"Live in sorrow, die in happiness" , even if human beings now stand at the top of the biological chain with their wisdom, we will still involuntarily worry about the future of mankind from time to time.
In fact, this worry is not unfounded. Although humans are the only highly intelligent creatures on the earth, but for the earth, we are no different from other animals and plants. We are still powerless in the face of the punishment imposed by nature.
Once a large-scale disaster really strikes, it is not surprising that most of the existing biological species on the earth will become extinct. It will be just like the five mass extinctions of organisms that the earth has experienced in the past. Judging from the current level of civilization, human beings cannot guarantee that they can survive alone and become the "chosen people" who survive.
Therefore, many people are worried: If humans in the future copy the fate of the dinosaurs, the former overlords of the earth, and suddenly disappear from the earth, will there still be traces of human existence on the earth billions of years later?
Fortunately, although we have not found evidence of the existence of mysterious prehistoric civilizations, our own traces can be preserved for billions of years.
This means that if new intelligent creatures appear on the earth after the extinction of humans, then they will definitely be able to determine that humans have appeared based on these traces.
Direct evidence of human existence: Fossils
Fossils are the remains, relics or relics of ancient organisms preserved in rocks. They play a vital role in the process of scientists "searching for the past and asking about the present." In ancient times without written records, people mainly used fossils to discover and restore organisms that lived in long ago.
Many creatures have appeared in the 4.5 billion years of life on earth. Some of them have been favored by the God of Destiny and have survived and multiplied to this day. There are also many creatures that have been eliminated by nature and lost in the torrent of history. To find these disappeared creatures, you need to find their fossils.
The reason why fossils are the best way to study paleontology is not only because it can relatively accurately represent the structure of animals and plants, but also because of its own inherent characteristics-extremely long shelf life.
If the area where the fossils are buried has not experienced large-scale geological activities, such as earthquakes, volcanic eruptions, etc., then the fossils can be preserved in them for at least billions of years.
It is worth mentioning that scientists actually discovered an extremely ancient fossil during the geological survey. After identification, it was found that this fossil has been preserved for 3.77 billion to 4.29 billion years.
This means that if humans become extinct, the fossils buried underground can prove that we once existed on the earth.
Maybe then we will be the ones placed in museums for people to visit. I don’t know what the creatures will call us later. It is still very interesting to imagine.
However, fossils can only prove that human beings have existed. It is impossible to show our civilization in fossils.
Man-made buildings show civilization
Perhaps by the time they disappear, humans will only survive on the earth for tens of thousands of years, but our impact on the earth will be indelible in a short period of time.
Just like the high-rise buildings in the city, even if humans suddenly become extinct, these buildings can still stand for hundreds of years. Even if they collapse in the end and are covered by the soil together with their former owners, those steel bars and concrete will look out of place on the land, and latecomers will surely discover their unusualness and discover that they are the former human constructions.
There are also famous landscapes scattered around the world, such as the pyramids of Egypt, the Great Wall of China, the Eiffel Tower in France, etc., all of which will leave traces of human civilization.
In addition to these, there are many chemicals that are not originally found on the earth, typical ones are plastic bags and cosmetics, etc. These items are not easily degraded and will not disappear within tens of millions of years.
Therefore, the human civilization we created will not disappear completely, and latecomers can also get a glimpse of the past human civilization.
Traces of stratigraphic disturbance will not disappear
Stratigraphic disturbance refers to a series of activities such as human destruction, transformation, and repair of the stratum. While humans are developing industrial civilization, they have also caused many irreversible disturbances or harm to the geological environment. For example, when building buildings, they will drive piles underground, and when building underground facilities, they will dig deep into the soil, etc., which will destroy the stratum.
More importantly, we also leave many things underground, such as metal objects and reinforced iron plates. Even after hundreds of millions of years of degradation, these things will leave metal ions in the soil.
If the technological level of the latecomers reaches a certain level, then they will definitely discover various trace elements that do not belong to the soil, thus discovering traces of human existence.
Traces in the Universe
The evidence of human existence is not limited to the earth. In fact, after humans stepped out of the earth and entered the universe, there were traces of humans in the universe.
First of all, there are footprints on the moon. There is no wind, no water, and no atmosphere on the moon. Therefore, the footprints of the astronauts who landed on the moon will not disappear in a short time and can be retained for a long time.
Then there is the Voyager probe , which is currently the farthest space detector from the earth. It carries a piece of very high purity "uranium". Uranium is a radioactive element with a long half-life of about 100,000 to 4.5 billion years.
Therefore, the Voyager probe is like a "human business card" . If alien creatures discover it, then they can use uranium to calculate the "production time" of the Voyager and the time of space travel.
In short, even if humans suddenly become extinct, the traces of human existence will not be completely erased. Aliens or latecomers on earth can use these types of evidence to discover the existence of humans in the past.
Conclusion
As far as the earth is concerned, human beings are no different from other creatures, and we have no special meaning to it, but the earth is not like this to us.
Without the hotbed provided by the earth, human beings would not have appeared, and human civilization would not have emerged. Without the earth, humans and human civilization would cease to exist.
Therefore, in order to avoid the tragedy of human extinction, we should protect the earth. After all, we only have one home: the earth.
