Earth degenerate

Global species degenerate, and human beings return ancestors.
The dog degenerates into a wolf, the cat degenerates into an ancient cat, the tiger degenerates into a sword -tooth tiger, the pig is degraded into a giant pig that can fight with the dinosaur …
The ancestor, Tyedon Dragon, Titan giant python, Canglong, giant shark, brutal lion, emperor crocodile, mammoth …
Ancient creatures that once dominated the ancient earth are coming one after another, and the ruler of the earth will return …