Still alive 200 million years ago

The fall of Crocodile louisi was of no harm to the little red dragons. Although it caused chaos in the ecological chain of this grassland, only if there was chaos could there be an opportunity to take advantage of it.

The central idea of ​​all Xu Dong's actions is to leave the grassland and enter the jungle.

Then it is easier to get out of the prairie where there are strict hierarchies, with large, medium and small predators eating food at different levels.

Or is it now that the top predators are dead, more than half of the middle and lower predators have been killed or injured, and it is easier to get out of the prairie with the ecological chain completely empty?

Therefore, in order to leave this grassland intact, Xu Dong boldly intervened in the tense situation before and helped ignite the rebellious hearts of the middle and lower class predators.

From the moment Crocodile Lowes died, the grassland no longer lived up to its previous calmness. Fighting broke out everywhere. Only one of the jaw-eating dragons that was supposed to temporarily take over the throne of Crocodile Lowes died, still with injuries. I don’t know where to hide at this moment.

Other medium-sized predators such as Cynognathus, Eoraptor, and Dromaeosaurus are all one meter in length, and they are all social animals. Without the suppression of taller and larger predators, they naturally fight each other on this grassland. , fighting for territory.

There was fighting everywhere, killing everywhere, corpses everywhere.

In such a chaotic situation, Xu Dong made the sixteen little red dragons nest in the cave and were not allowed to go out. He often went up to steal some remaining flesh and blood, not only to fill the stomachs of his tribe, but also to earn some source of essence and components for himself.

Xu Dong knew that this chaos would not last long. After the predators were full and the forces were re-divided, the grassland would calm down and wait until new predators filled the ecological niche.

The period when the predators calm down is the best time for the little red dragon family to leave. No creature will pay attention to these little guys of more than ten centimeters when they are full.

Moreover, the scale of this grassland shuffling operation was so large that Xu Dongguang had a great harvest just by picking up broken limbs and scraps of meat. Guangguang Source Quality obtained twenty-two points. What surprised him even more was that he finally got the component he had dreamed of. .

[Eoraptor's air sac]

As we all know, the rise of dinosaurs was due to a mass extinction at the end of the Triassic that reshuffled the forces of Pangea. Dinosaurs survived the Triassic mass extinction and multiplied rapidly, and their species spread across all ecological niches.

But why are dinosaurs rising instead of worms, pseudosuchians, spondyloids, turtles and turtles?

The reason lies in the three advanced internal components of dinosaurs: an advanced air bag structure similar to that of birds (or inherited from birds), a constant temperature system that violates the ancestors, and a high metabolic rate.

The oxygen content in the Triassic was extremely low, only about 15%. In order to maintain its own needs, the archosaurs developed a set of advanced double-layer filtering air sacs. The gases were exchanged twice as they entered and exited, ensuring that the The exhaust gas is completely exhausted to improve oxygen utilization, so that pterosaurs and birds will not be deprived of oxygen even when flying at high altitudes.

As for mammals, even after 200 million years of evolution, the respiratory system efficiency of modern humans is only one-fourth that of birds.

Of course, the airbag is not only good for oxygen utilization, but also made an outstanding contribution to the huge size of dinosaurs. The airbag occupies a large space inside the body, but like a balloon, it only takes up volume but not weight.

While the dinosaur's body became huge, it was still much lighter than other creatures of the same size. It was by mastering this ripple breathing method that it created an era of giant beasts that lasted 130 million years.

Many people in modern times have a misunderstanding that dinosaurs became gigantic because of the high oxygen content at that time. In fact, this is not the case.

The oxygen concentration in the Jurassic was 15-21%, and in the Cretaceous was 21-26%. In the dinosaur era, there is actually not much difference compared to the modern 21%.

The oxygen content of the atmosphere is mainly related to the size of insects, which use tracheae for gas exchange. The oxygen content in the Carboniferous reached 35%, so the largest insects in history were born.

The enlargement of vertebrates has little to do with oxygen concentration. Basically, it just needs to be enough.

The next few days were spent eating, eating, eating, eating. The extremely bored little red dragons even started digging holes in the soil looking for small bugs to eat.

It was not because of hunger that Xu Dong went out to look for food every day. There were corpses everywhere on the grassland, and there were too many to eat. The little red dragons dug holes simply because they felt bored staying in the holes.

There are too many corpses mainly because there are too few scavengers in this grassland. Birds and pterosaurs have not yet evolved, so they basically can only rely on bugs and small synapsids to digest them.

More than 10 million years have passed since the brutal end-Permian mass extinction. Even the Zerg, known as the king of life, has been severely damaged. In addition, flies, ants, scavenger bees and other scavenger kings have not evolved. Basically, Only the old guys, Zangjia, were working hard to clean up the corpses.

Natural cleaning speed cannot match the production speed.

Xu Dong went out to look for food again that day. It was rare that it didn't rain. The sun in the sky warmed the earth. He ran on the grassland for a long time but didn't find any other predators.

In the past, there were small predators such as rheodonts, squeaky titans, and chinensis that competed with him for food, but today there were not many of them at all, even the few chinensis that he saw. The beast was also lazily basking in the sun and had no intention of competing with Xu Dong for food.

When all the predators in this grassland have eaten their fill, it is time to leave the grassland.

Xu Dong went into the cave to greet his sixteen brothers. The little red dragons couldn't wait to climb out of the cave one by one.

The first few little red dragons who had just exited the cave spontaneously went on guard until all the little red dragons climbed out and then joined the queue.

Xu Dong led his sixteen little red dragons and ran wildly on the vast grassland, rolling up smoke and dust along the way and startling many flying insects.

Several plains dromaeosaurs were lying lazily on the dry open ground basking in the sun. They had been so full recently that they had almost eaten all the meat they had eaten in the previous half year, which made them a little drowsy these days.

A plains dromaeosaur raised its small head and looked around cautiously.

As a result, after looking around for a long time, I discovered a group of little guys running in the distance.

In the past, food delivered to your door would have been accepted without any courtesy.

But I've been too full recently and don't want to move. Not to mention running far away, the plain dromaeosaurs are not happy to pay attention to them even if they run in front of them.

The little red dragons ran all the way, past the dromaeosaurs on the plains, past the burrows of the traversodon, and past the lair of the cynognathus. There were no predators chasing them on the plains.

That’s weird!

When the team of little red dragons ran to a pile of rocks on the edge of the grassland, a huge dinosaur suddenly jumped out and chased after them.

The little red dragons were almost scared to death when they saw such a big guy, and each one ran harder than the other.

Xu Dong quickly ran ahead and had time to think.

Isn't this big guy the remaining jaw-eating dragon? Why did it hide in the rocky beach? What's even worse is that it looks like it's hungry.

You don't eat so much meat on the plain, but you chase after these few ounces of meat from the little red dragon. How do you think you are a dragon?

Gnathognathosaurus belongs to the genus Herrerasauridae and is a small to medium-sized carnivorous dinosaur. Herrerasauridae belongs to the basal saurischian order.

The author has been participating in epidemic prevention recently, and has many things to do and is busy. The number of updates can only be guaranteed to be once a day. If the recommendation comes, I will update it twice even if I don't sleep at night.