The diagram below shows the development of the cutting tool in the Stone Age.

The diagram describes the evolution of three faces of 2 cutting tools in one of the

primative

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primitive

ages, the Stone Age. They are named

Tool

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A and

Tool

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B

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. One of the most noticeable features between these two cutlers is that the latter looks a lot more sophisticated and efficient in

term

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terms

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of cutting function than the former.

Firstly

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, look at the front view of

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tool

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tools

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A and

B

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. It can be easily recognized that the cutlers turned to be more pointed and sharper after around 0.7 million

years’

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years

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development

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of development

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.

Secondly

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, the side views of tools A and

B

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reveal a remarkable difference in their sharpness. If the sides of these 2 cutting utensils were used to cut things,

such

Linking Words

as animal meats, fruits, etc, the side of

tool

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B

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would work efficiently like

a

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the

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honed blade of

knife

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a knife

the knife

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. The side of

tool

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A, which is 1.4 million years old, had a rather blunt edge.

Thirdly

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, the back view of

Tool

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A has a more acuminate tip / head than that of

Tool

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B

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.

Nevertheless

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, in

term

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terms

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of

overal

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overall

beauty,

Tool

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A’s back, especially its lower part, looked very rugged

while

Linking Words

Tool

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B

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’s back

were

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was

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made to have a smoother surface over time.