Dinosaurs have lived on Earth for millions of years. If it were not for the asteroid, the reign of Tyrannosaurus Rex and the like could have continued even further! But what would happen to us then? What would life be like on the planet now if dinosaurs were not extinct?
Just imagine, you are looking out of the window, and dinosaurs are walking around the city! Is this possible, or did you end up in the Flintstones cartoon?
Unfortunately (or fortunately) such a scenario would not be possible for two reasons. First, because life is constantly evolving. This process can be seen even among the remains of dinosaurs, because there were simply an unthinkable number of them!
Therefore, if the asteroid passed the Earth, the dinosaurs would continue to evolve. Species that flourished at the end of the Cretaceous, such as Triceratops, would leave offspring that continued to change over time. Thus, if dinosaurs survived until the 2020s, they would be very different from their ancestors.
However, humans most likely would not be able to see what the dinosaurs have become. Despite the fact that many mammals flourished during those times, they were very small in size. The largest Mesozoic mammal was the size of a badger. Although the first primates evolved towards the end of the reign of the dinosaurs, they had more in common with the shrew than with humans. If dinosaurs were somehow able to maintain their position in the world around them, they would undoubtedly continue to influence the evolution of mammals. The evolutionary history of our ancestors would have been different, almost certainly humanity would never have appeared.
But all these theories aside, it's worth noting that we do exist among dinosaurs! Birds are living dinosaurs. They originated in the Jurassic and flourished alongside their non-avian relatives. The only reason we think of birds as a completely different animal is because sparrows and pigeons don't look as dramatic and intimidating as stegosaurs. This also confirms the idea that if the asteroid had not then fallen to Earth, the ancient dinosaurs would have changed dramatically by our time.