Through Xiao Yi's explanation, Yang Meng quickly understood the difference between the two,

Although animal paleontological fossils have more words than paleontology, there are more words "animal".

But it is these two words that make paleontologists confused about some of the processes in the history of the earth's biological evolution.

According to the general theory,

Organisms have evolved step by step from primitive single-celled organisms to the extent that they are today.

Earlier such theories were only hypotheses,

But through modern gene sequencing technology, researchers have found that

The human genome has a small number of genes that are homologous to ancient cyanobacteria.

Not only cyanobacteria, but also bananas in humans and plants are genetically similar to 50%.

In addition to this, E. coli, paramecium, wheat, apples, flies, ants, snakes, ......

Biologists extract genetic sequencing data from a wide variety of organisms on Earth.

There are more or less genetically similar fragments between all organisms,

To some extent, the data can illustrate,

The origin of the organisms on the earth may be the same, but due to the changes in the earth's environment, they have taken different paths.

But something troublesome happened,

The oldest fossil of a creature found by humans is a microbial fossil.

This fossil was found about 3.4 billion years ago on the island of Greenland, near the North Pole.

Therefore, it can be determined that there was life on Earth 3.4 billion years ago.

However, in the interval from 3.4 billion to 560 million years after the discovery of animal fossils,

The microbial fossils found can only be seen by a microscope, but the animal fossils that can be seen with the naked eye are not eyebrow at all.

Until 560 million years ago, a large number of animal fossils appeared abruptly,

And that's strange to paleontologists.

Animals can't, clatter, and then snapped and were crushed into the ground,

During this period, there is a general process of change, from microorganisms to animals.

However, this seems to be how the animals on the earth suddenly appeared.

With 560 million years as the node,

Humans have not found any animal fossils 560 million years ago,

And 560 million years later, there are a large number of biological fossils.

The number of fossils led paleontologists to name that period: the Cambrian Explosion of Species, which officially opened the way for the evolution of life on Earth.

As for the cause of the Cambrian species explosion, what made the bacteria and viruses in the earth's oceans suddenly go in the other direction.

It's still a matter of debate,

Fortunately, Yang Meng doesn't need to know those complicated inferences.

All he needs to know is that

Since 560 million years, there has been a sudden increase in the variety of organisms on the earth.

Even though there have been several mass extinctions during this period,

But traces of the Cambrian explosion can still be found on Earth today.

"Is it a coincidence?"

Yang Meng looked at the flickering points of light in front of him,

The time when the Rutans discovered the Earth also happened to be the time of the first biological explosion on Earth.

can think that the Rutan people have not been able to leave this galaxy so far,

And at that time, Rutan was still several light-years away from Earth,

It was also very difficult to reach my earth at that time across such a long distance.

Yang Meng pondered for a moment, suddenly thought of something, and continued to ask Xiaoguang:

"You just said that the earth environment at that time was harsh,

What kind of technology did you use to detect the global environment at that time?

"Hmm~ this question? I need to retrieve it! ”

Xiaoguang responded to Yang Meng's words, and began to flicker rapidly, as if he was really remembering something.

Seeing this, Yang Meng recalled the question he had just asked, and his heart was also full of doubts.

With the current astronomical observation technology of human beings, it is still difficult to see the specific situation on a planet in a galaxy.

But the Rutans seem to have such technology,

"But how do they do it?"

You know, stars make up the vast majority of the mass of a galaxy.

For example, the mass of the sun accounts for 99.8% of the entire solar system.

The other planetary moons, compared to the sun, are like dust,

Even if Jupiter, which is 318 times the mass of the Earth, is placed next to the Sun,

If it is a normal size and proportion, it is just a small dot.

Of course, in textbooks and video images, it is obviously meaningless to mark each planet as a small black dot

Therefore, the legends that are usually seen have been enlarged and modified according to the scale.

And such exaggerated proportions,

It is obviously very difficult to observe the planets in the solar system through the interference of the sun.

And the planet itself does not emit light,

It can only be seen with the naked eye by reflecting the light emitted by the sun.

Therefore, although mankind entered the astronomical age very early,

But the discovery of extrasolar planets was much later......

In 1543, Copernicus published "The Movement of the Heavenly Bodies", which established the heliocentric theory,

It also officially opened the era of astronomical observation of modern mankind.

From the sun to other stars, to the entire galaxy, the places where humans can see clearly are getting farther and farther.

But apart from the solar system, mankind has not been able to find a planetary system like the solar system.

During this period, mankind experienced the age of sea navigation, the industrial age,

Two world wars, nuclear bomb explosions,

Despite the rapid progress of science and technology, it is still impossible to find planets outside the solar system.

Faced with this situation, there were even professional physicists who proposed the famous Fermi paradox in 1950,

It is believed that in this case, human beings are the only intelligent life in the universe.

After that, there was still no trace of the planet, and the Fermi paradox was gradually accepted.

After that, man landed on the moon, launched a probe to Mars, a probe to Jupiter,

Voyager 1 and 2, which were launched out of the solar system in 1976,

However, in this case, mankind still has not found a planet outside the solar system,

And until October 6, 1995,

At a time when mankind has just entered a new era of information networks,

Two astronomers from Switzerland, after a very long period of observational research,

At the International Astronomical Conference in Florence it was announced that they had discovered the first planet outside the solar system,

Witnessed by leading astrophysicists from various countries,

Humans are sure that the star also has a planetary system like the solar system.

From 1543 to 1995,

The process of discovering exoplanets is extremely long.

And the Fermi paradox, which was born decades ago, has also been swept into the dust of history.

Such a long and difficult process of planetary discovery,

Enough to illustrate how difficult it is to find planets hidden by the light of stars outside our solar system,

And a planet of Earth's physique is even more difficult to find.

"What kind of technology do the Rutans use?"

Looking at the small light in front of him that is gradually becoming gentle,

Yang Meng had a hunch that it was very likely that he would once again dig out a new technology that had not been mastered by human beings in Xiaoguang.