The diagram gives information about the cutting tools which humans used to cut things in the Stone Age.
Overall, it is clear that the cutting tools upgraded dramatically over the 0.6 million years. It is noticable that the tools in picture B was much convenient for cutting purpose.
Looking in the first pictures, tool A showed up 1.4 million years ago and it measured was about 10 cm in length. Turning to the tool shape, it was quite basic bumpy surface. At this time, the cutting tool A was blunt, it was difficlt for humans to cut things.
Regarding to tool B, it dated back to 0.9 m illion years ago and its length was equal. the former tool was appearence, wwwe can see that it had a regular shape, same like a waterdrop abd large size from the back view than tool A. The most noticable dissimlilar between two tools that the recent tool was sharper with a point at the top,cutting more easily. Morever, the improved shape allowed holding more tightly
