Yiyun Lei took Rao Ya and followed the slowly rolling ball, walking slowly. Passing by this land with subtle fluorescence and clear continuity. I don't know why, in such a space, perhaps, because there are no human beings. The air is even fresher than the outside world.

Oxygen levels also seem to be higher. Also, the temperature here is not low. In this dark and deep underground, its temperature is actually constant at about ten to twenty degrees. It's like the temperature of spring outside, or autumn. And this temperature is the most suitable for the growth of organisms.

What's more, in this space that I don't know how deep and wide it is, there is actually wind!

Yun Lei took Rao Ya, and after walking a distance, he actually felt the breeze blowing in his face while walking!

And this breeze blows Raoya's long hair. Soaring. At the same time, there were some people who were taller than Yun Lei and Rao Ya, and the entire mushroom cap emitted a strong fluorescence, like a giant mushroom with a large table lamp. and some small luminescent fungi.

These fungi multiply through the spread of spores. And those spores, which emit subtle fluorescence, rise with the wind. Straight up. Yun Lei looked up at the black dome. I found that the height of the dome was at least several thousand meters!

That is, it is equivalent to the surface world, from the surface upwards, reaching or even exceeding the height of the troposphere. At this altitude, the formation of temperature differences, the formation of air convection is absolute. If it doesn't form, it's a strange thing.

With the formation of air flow and circulation, the circulation of water in this space is also naturally formed. Yun Lei and Rao Ya could clearly see that there were clouds in this space thousands of meters high.

The reason why the two of them were able to see the clouds fluttering on the dark dome from where they were. It's because it's because it's the wind, not just the moisture. Moreover, there are those spores that emit subtle fluorescence, and these luminescent spores are very lightweight.

It was just stuck to the clouds on these domes. Just like in the outside world, some dust, haze, fungi and bacteria also migrate and spread with the clouds. Therefore, these clouds, after sticking to these spores, are also stained with a faint fluorescence.

This is a faint fluorescence, although not very strong. However, it is no problem to see its presence in this dark cavern. After all, the clouds that are flowing and surging in the sky are spreading out continuously. It is not weaker than the outside world. It's hard to see without seeing.

Of course, there are also some luminous fungi that grow on the rock walls of the dome several kilometers high, and the light emitted is like the stars in the night sky.

Yun Lei led Rao Ya through the jungle of giant mushrooms, mosses, and low ferns.

Along the way, many huge creatures were shocked. That's an ancient insect that has long been extinct in the outside world!

In the evolutionary history of life on Earth, in addition to vertebrates, which now rule the entire earth, there is another kind of creature that is completely different from vertebrates, that is, arthropods, specifically, various insects that can belong to the phylum Arthropods, once ruled the planet.

Then, it was animals like dinosaurs that moved from the sea to the land and gradually ruled the world.

The pinnacle of world domination of these giant insects was in the Carboniferous period, 300 million years ago. According to archaeological finds, these ancient arthropods included oversized mayflies, scorpions, spiders the size of spider plants, five-foot-long millipedes, giant dragonflies, and ancient centipedes.

More volume means more cells, more neurons, and the right way the body is structured and composed. Although these giant insects are huge, their specific body size, in fact, is not much different from the limits that today's mammals can reach.

According to evolutionary practice, this body type should be the most suitable for the reproduction and evolution of life on earth.

At the same time, insects have evolved more than just their bodies. According to scientific anatomy, insects not only have brains, but also complete nervous systems, and the central nervous system of insects is made up of a brain and a ventral cord nerve. The ventral chordate in insects can be compared to the notochord in humans. It is located on the ventral surface of the digestive tract, including the hypopharyngeal ganglia of the head and a series of ganglia and nerve cords in the thoracic and abdominal areas.

The brain of an insect functions similarly to the human brain, which is the center of contact and coordination, connecting the nerve fibers of all the sensory organs of the head, as well as all the motor nerve units in the mouth area, chest and abdomen, and regulating the secretory activity of the endocrine glands, thus regulating all the activities of the insect.

In this case, who knows if it is possible for these insects with the right size, complete nervous system, and sufficient neurons to evolve into intelligent insect people!

Perhaps, those ancient insects are only one step away from success.

Perhaps, the ancient earth almost became the origin of the Zerg who conquered the universe!

And once insects are born with intelligence. Then the establishment of civilization is only a matter of moments. After all, it has only taken a few million years since the emergence of human beings and their evolution to the present, and in the context of hundreds of millions of years, it is only a moment.

These giant insects, due to the decrease in oxygen content in the atmosphere and the rise of vertebrates, the earliest amphibians, gradually died out over a period of 50 million to 100 million years, in the middle to late Permian. Then came the rise of vertebrates.

Amphibians appeared between 300 million and 235 million years ago.

According to scientists' analysis of fossils, it was found that some characteristics of these ancient giant insects are not much different from those of modern small insects. The only big difference is the size. In other words, if these modern insects go back to ancient times, after several generations of reproduction, it is possible to regain the huge size of ancient insects.

Because, as long as the oxygen content in the air is enough, then those ancient insects with huge sizes can survive. After all, the vitality of insects is really amazing. Moreover, its competitiveness is also exceptionally strong. Not to mention the amphibians that had just appeared on land back then.

Even some vertebrates that have evolved for a long time may not be able to compete with these insects. Humans sprinkle pesticides and kill insects every year. How has this worm ever been extinct?