Based on the timeline, the climate in ancient times was . the climatic changes were drastic. the planet suffered from hot and cold climatic conditions. there is no strict pattern that the weather seems to follow. only one thing is certain: the winters became as time passed by.

the answer is The planet suffered from hot and cold climatic conditions. 
In the past, the Average earth temperature is indeed moving up and down, but the movement is not deviationg from 0.5 C on average.
While he average change that The earth experience in recent years has became drastic compared to the ancient years.