What do fossils tell us about the process of evolution? (5 mark question)

Fossils are preserved traces of living organisms. When we dig into the Earth and start finding fossils, it is reasonable to suppose that the fossils we find closer to the surface are more recent than the fossils we find in deeper layers. This gives us an idea of the relative times these organisms existed on Earth. Fossil dating also gives us an idea about the age of the fossil. A study of fossils in different sedimentary layers indicates the geological period in which they existed. This study shows that life-forms varied over time and certain life forms are restricted to certain geological time-spans. Hence new forms of life have arisen at different times in the history of Earth. Hence fossils are instrumental in tracing the process of evolution.