How the Earth has changed DBESpace: The final frontier. We have sought to uncover the mysteries that shroud this great expanse and even our own Earth for as long as we have existed. Over 4 billion years ago planet Earth formed and over the following eons more and more evolutions occurred and subsequently more and more theoretical explanations for how they occurred formed. While we may not know the details of how Earth came to be, we do know the sequence of many events that took place. Knowing this will help us deepen our quest to find the true answer to the formation of the Earth once and for all. Life on Earth, the sequence of certain events, and the various theories that have emerged have contributed to changing the Earth or explaining changes to the Earth. Earth is a truly unique planet. It is currently the only planet in our solar system capable of supporting life. It has liquid water, tectonic plates responsible for the movement of our continents, and an atmosphere that protects the inhabitants of the Earth from the strong rays of the sun. However, the Earth was not created spontaneously in this way. Over millions of years the Earth has changed and, strangely, the life it hosts has had a huge impact on its development. Plants, for example, have helped shape our planet in many ways, one of which is physical. During the Cambrian period the rivers were very flat and shallow and were not at all complex. According to new research, “The evolution of land plants, along with the help of mud, eventually gave rivers the narrow, meandering channels, islands, muddy floodplains, and species-rich corridors associated with modern rivers…” ( How Plants Helped Make the Earth unique 2). Fast forward... middle of the paper... the theory has now become the unofficially accepted one. It is stated that “clear evidence has been obtained to support the idea, originally proposed by Luis Alvarez, that a global catastrophe, caused by the impact of an asteroid, comet or meteorite, was responsible” (The Age of Mammals 1) . As is evident, nothing in the world of science is absolute, especially when it concerns the mysteries of the Earth's past. Although we don't know much about Earth, science continues to prevail and continues to make discoveries. These discoveries give us a glimpse of what the Earth was like before humans inhabited it, and even after. As the years go by, our methods improve and we are able to not only eliminate many theories and narrow the field, but also organize the events that occurred. Once we know the order, we come closer to uncovering the secrets that confound Earth's past.