Geological Timeline Reflection

Earth's history is long and ever-changing, shaped by major events that altered Earth as we know it, but three major events were especially important in constructing the world we live in today. Probably the most important event, that allowed most if not all life to thrive, is the oxygenation of Earth which occurred about 2.3 billion years ago and was caused by the photoautotroph cyanobacteria. Oxygen produced by photosynthesis (cyanobacteria), helped to give rise to other organisms and eventually multicellular eukaryotes. In addition, the movement of arthropods onto land and eventually larger vertebrates was also a big event in Earth's history. Movement onto land led organisms thriving off the plants, eventually leading to more advanced organisms like reptiles and mammals. Finally, the evolution of mammals, specifically humans, was one of the most important events in the history of the Earth. Humans, Homo sapiens, have had one of the greatest impacts on the Earth in such a short time.

During the course of the geological timeline project, we had to observe and measure out the scale and size of Earth's history, and throughout this process, several things surprised me. First, is how long the Earth took to develop: the first bacteria/prokaryotes appeared about halfway through Earth's history and the first eukaryotic life forms appeared about 500-600 million years ago (Earth is 4.6 billion years ago). Another thing that surprised me was how short of time humans have been on the planet, so short in fact that it was impossible to mark how long humans had been on Earth on the geological timeline we made. Finally, another interesting thing I observed that is somewhat related to the scale of Earth's history, is how life has exponentially evolved in complexity so much that we as humans have only been here for about 200,000 years back to our oldest ancestor.

As I begin to observe the history of the Earth, I realized that humans have made such a big impact on the planet in such a small amount of time. Humans have been on the Earth for a micro-fraction of time, and yet we have become so advanced surpassing any other species in intelligence by a longshot. And yet we over the past 100 years, which is a blink of an eye in geological terms, we have also damaged the planet heavily with pollutants, causing global warming and other climate change issues. Earth has existed in the universe for 4.6 billion years, but the human race, which has only become civilized has caused more damage to the planet than any other organism that has ever existed on the planet. There have been a total of five mass extinctions in the Earth's history and if we don't do anything about it, there might be a sixth one.