Answer:
The rock and fossil record shows that all of the changes in the Earth's history have been slow and gradual.
Step-by-step explanation:
Rock and fossil record are of evolutionary importance, because these records gives ideas regarding the time since existence of life in Earth. This information can be used to to get a clear picture regarding how the living organisms of ancient age interacted with the environment of that time. The records thus obtained from rock and fossil are sufficient enough to conclude that evolution do are taking place which is very slow and gradual in such a way, so that it could provides for adaptability to the changing surrounding environment.