All living species go through evolution.
Before the Chicxulub crater impact, there were no humans. After the impact humans walked the earth millions of years afterwards....a geological blink of the eye.
I think all species live for a while, then some massive extinction occurs by a natural phenomena. Consequently, (through evolution) a new species is derived.
Humans have been walking the Earth for thousands of years. Thousands of years is negligible when compared to the age of the universe.
Personally, I think we evolve for a while, then go extinct, then evolve again and the process repeats itself. Ofcourse we are talking billions and billions of years here. Imagine all of man's discoveries have to be "re-discovered" in the next generation.
So if we were to say that each evolution path/journey is ONE generation of man/life, then we are in an existing generation. In this generation, great people like Sir Issac Newton and Albert Einstein came up with extraordinary laws and discoveries (like the Theory of Relativity).
Who knows how these discoveries were established in previous generations. Maybe Newtown's Laws were phrased differently and discovered by different people. Maybe our mathematical formulae might have been slightly different. Maybe we had different types of humans that walked the Earth. Maybe the Internet never existed. Maybe we had some form of super telepathic technologies yet to be discovered. Maybe?
It is said that Newton came up with the laws of Gravity inspired by an apple falling on his head while sitting under a tree. How did our past generation discover the laws of Gravity? Newton's experience is quite unique and one would expect past discoveries such as this would surface quite differently. What led to the discovery of the Gravity laws in our past generations?
After the Chicxulub crater impact, some underground mammals survived. This led to us humans but killed all dinosaurs in the process.
Sometimes I humour myself and think that the asteroid brought human life to Earth...it did actually if you really think about it. It got rid of the dinosaurs which led to the evolution of man...eventually. We know it brought water, a critical element for the sustenance of life. The blood pumping through your veins contain water which originated from this massive asteroid. That's a fun fact.
The Earth is a marvelous planet. It is really awesome. No matter what we throw at it (noise/air pollution etc), the Earth recovers naturally. It might take a while in some cases but it eventually stabilizes. Did you know that because of the high rate of carbon dioxide flung into the atmosphere by us humans, this has triggered the forests to grow faster to combat the CO2 levels in the air? That is amazing. The planet fights back! Naturally ofcourse.
It is this balance of all the elements that sustains life and no other planet has this balance....isn't that food for thought? To know that out of all the planets in the entire Universe discovered by man, only Earth has exactly and everything needed for life. A very delicate balance indeed.
As National Geographic quite nicely put it: Asteroids, they carry the virus of life across the Universe.