Why are humans afraid to bring Martian soil back to Earth? What are they afraid of?

Mars is a planet of great interest to many countries, mainly because its environment is very similar to that of the Earth. Last year, Mars was discovered for the first time in a liquid lake covered by Antarctica, which increased people's desire to explore Mars, and many countries conducted research on Mars. Many people speculate that 3 billion years ago, Mars might have a civilization as splendid as today's earth, but due to irresistible factors, Mars eventually became an uninhabited planet.

But researchers have been shuttling between Mars and Earth. Why can't they just bring something back to Earth from Mars for research? You know, this is absolutely impossible, because it is an irresistible factor. Because the soil on Mars has always existed in the Martian environment, if it suddenly reaches the earth, it will mutate, just like many creatures on the earth die and produce microorganisms.

The soil on Mars may change. If scientists can't stop this from happening, just like the biological hazards in American movies, it may infect all countries in an instant and become a huge disaster. This is beyond human control, and human beings may become extinct in this crisis. So if you change the living environment of a thing, it is likely to directly change the overall nature.

The same is true of Mars. No one knows what is in the soil you brought back and whether there will be any variation, so don't blindly choose what to bring back to Earth. Nature has its own operating law, and if this law is forcibly broken, it may bring irreversible harm to itself.