Geologic Timeline Individual Reflection

       Three of the most significant events that have occurred in earths geological history are the "Cambrian explosion:, the Permian extinction, and the Cretaceous extinction. The Cambrian explosion is the time period where a large amount of new species arose, and the diversification of current species rapidly grew. It created a prosperous time for new animals and allowed for a diversification in sea life, which led to the Permian era. Without the Cambrian explosion, much of earths current life would be non existent, and the Permian era sea life growth would never have occurred. The Permian extinction was the largest mass extinction ever, and caused the destruction of 70% of all species. This extinction caused decimated the large amount of aquatic species on earth, and created a niche for the Dinosaurs and other animals to step into. The Permian extinction is thought to be caused by a drastic increase in temperature, which caused many glaciers to melt and allowed for the continents of Pangea to dry up. with this extinction, Earth would still be largely aquatic and have much larger glaciers. The Cretaceous extinction is the third significant event because of its lasting effect on humans and its destruction of the Dinosaurs. Without this extinction, the earth would still be ruled by the Dinosaurs, and humans would hav
e never found and inhabited their niche.

http://www.basfeijen.nl/evolution/pic/cambrianfauna.jpg

     Despite the scale of earths history being so large, what surprised me is how little time humans have been on earth, and how in the grand scale of time, our actions and lives have had a minuscule effect on what has occurred over time. As seen in the Cosmos video, if earths history was a calendar year, we take up the last second of the last day, which truely shows how small we are in the grand scale of things. Despite us having been on earth for such a short time, we have had a large impact on our planet. From global warming to the extinction of many species, we have caused much harm to our earth and have created a lasting impact. With continued increase in temperature, we may be causing our own extinction.

https://spongebobquh.wikispaces.com/file/view/geological_time.jpg/128735281/geological_time.jpg