Geologic Timeline Reflection

   One major event in earth's history was the Cretaceous-Tertiary Extinction. The Cretaceous-Tertiary Extinction was when the last of the dinosaurs exception of birds went extinct. This extinction is a significant factor in the transition from the age of the dinosaurs to the age of the mammals eventually creating human. Another major event in earth's history was the appearance of cynobacteria. Cynobacteria helped to change the atmosphere into one with a higher concentration of oxygen. This oxygen was then toxic but it was later used by more advanced organisms in respiration, like humans. And a third important event in earth's history was the Cambrian explosion. The Cambrian explosion was the relatively sudden appearance of advanced organisms in the Cambrian era. These organisms created in the Cambrian explosion would later evolve into all the multi cellular plants and animals in geologically a relatively short amount of time.
   On our 10 meter long geologic time line of earth's history almost all of the major events happened in only the last 2 feet. This is surprising in how little amount of geologic time it took for much of evolution to take place. And what's even more important about this geologic timeline is that we as the human species can greatly change the face of the earth over only a few thousand years and at a more significant rate over only a couple hundred years. And this is relative to 4.5 billion years that the earth has existed as a planet. The vodcasts and our geologic timeline where very full of information therefore I have no unanswered questions.