Geologic Timeline Reflection

Three major events in Earth’s history, in order, include the cambrian explosion, the colonization of land plants, and the end cretaceous extinction. The cambrian explosion is important, because it was when life really started to speed up. In only a “few” million years, what was originally microorganisms and unicellular eukaryotes turned into a massive diversity of strange-looking aquatic life. The colonization of land plants also was important, because it allowed enough oxygen in the atmosphere for land organisms like us to survive. The end cretaceous extinction, although one of the less devastating extinctions, had left the earth with 75% or more of its species gone. This had included the dinosaurs, the pterosaurs, and giant marine reptiles, officially ending the 136 million year long reign of the reptiles and dinosaurs. This allowed smaller mammals who had a better chance of survival to become the next common ancestor, leading to the new reign of the mammals, including us.

The scale of the Earth’s history is astounding, but I was not particularly surprised by the scale of it. In our classroom and my science teachers from before time and time again often emphasize the fact that we are merely a fraction of a blink of an eye, compared to the vast time that has passed throughout the existence of the universe.  Not only this, but in my seventh grade biology class, we did a similar timeline of the Earth at the end of the year. I was doing my project with Austin McAllister, so I had to do basically all the work. However, the thing that did surprise me was the vast stretches of seemingly no development or change. Evolution seemed to almost meet an equilibrium. In the short amount of time that we have revolutionized ourselves and taken over just about every inhabitable place on Earth, I question myself whether there could've been time in the past for an intelligent species like us to evolve, given the vast stretches of time on Earth, where multicellular complex life was existent and thriving.

My thoughts on the immense changes that has happened to our Earth since we have began to exist is that it was all really according to plan. We may have won the biological lottery and had just the right luck to evolve into a species with the ability to understand its surroundings and appreciate its existence, but had it not been us, it could've easily been another species around the same time. I see the Earth’s aging as means of exponential growth. I saw, once, in a math problem, where if one were able to fold a standard 0.1 mm paper 26 times on itself, it would have the thickness of mount everest. Of course, this is not possible, but it just shows how powerful exponential growth really is. On the geologic timeline of Earth, it is not much different. Life is slow to begin with, and it took billions of years between the dawn of bacteria to the first eukaryotes with the ability to reproduce themselves. However, as time went on and as exponential growth occurred, life has begun to pick up pace. It still continues to do so today, with our technology following similar trends. Life on Earth was bound to eventually have intelligence. It wasn't a chance thing, although our species on its own was, but rather it was that intelligent life was going to eventually occur, given the rate that life advances on Earth.

My question is a follow-up to the previous one. There have been billions, if not trillions, of Earth-like planets that have existed in the universe, some as we speak. I find it strange that there is no almighty species of an organism which evolved before us on an alien planet, which is very likely given the amount of chances and time life had to appear. There still have not be a single piece of evidence that life has existed outside of our solar system, so either our technology is not advanced enough or life is simply really rare and we are lucky winners (woohoo!). But does that mean we will forever be alone on this universe, that there hasn’t been any previous species of intelligent lifeforms as a sort of way for the universe to “experience itself”? No one quite knows the answer, but this mystery is one of the top of the FAQ list in the biologist community, and it is one of the peculiar things that make up this universe as a driving force for us to try to discover more and dig a little deeper, which, for some reason, is what us primate descendants seem to be quite good at doing.

A pie shaped timeline of the Earth
This is similar to our timeline, except in a clock-like manner