Alien, the earth under our feet is an unstable guy. For billions of years, I don't know how many ethnic groups like us have different levels of civilization development and different forms. Because of various climate changes and geographical activities, a large number of people died. However, many survivors live in different areas, and they will also develop their own civilization. However, due to the lack of education in the process of reproduction, civilization declined and technology disappeared in time and war. For example, even if only a few hundred scientists are alive now, the civilization inherited by their descendants will disappear with time. Because knowledge can only survive, develop and continue in application. On the other hand, useless knowledge (what's the use of mathematics and astronomy in the key struggle for existence? ) will be forgotten. Only food is the most important thing. So agriculture is the most practical significance. The climax of our civilization may have been ignited by the afterglow of the last climax civilization. Our development is not a zero starting point, but a continuation of human heritage.

How many changes have our solar system experienced? Humans have lived on Venus, Mars, Earth, Titan and other planets that may crash. If Venus fails, it will go to Mars. If Mars fails, it will go to Earth. Perhaps life in the solar system has never existed, but it is between these planets. Aliens who are kind to us may be our ancestors, while those who are malicious are people from other galaxies.

Today, we imagine aliens, a bit like gorillas imagine all aspects of human beings. "There are humans? What magical power do they have? "

I mean, we're just descendants of the last civilization. From the decline of civilization to the present level.

20 12 probably nothing will happen, but biological cleaning has been going on for nearly a hundred years!

We can imagine that the last civilization was similar to ours now, but the concept was a little different and the number system was different. But people are still the same, with the same face, secular desires and emotions.