1.   From archaeological evidence we can reasonably infer that these people used stone cutting tools.

2.   Two million years ago our ancestors began to fashion stone tools.

3.   Some two million years ago our ancestors began to fashion stone tools and launched an evolutionary career which would ultimately have an impact on the entire planet.

4.   The slopes of Olduvai Gorge are littered with thousands of primitive stone tools.

5.   Man owes his existence to the maker of those primitive stone tools, who planted the seed of the human career.

6.   They could discuss the problems of skinning an animal, or scraping skins to make leather using only stone tools.

7.   An international team of geologists and anthropologists unearthed a trove of stone tools from the fossil reef along the Red Sea coast of Eritrea.

8.   And many of the dwellings showed an array of stone tools, as if residents fled and left them behind.

9.   And there are still lingering questions over the putative stone tools.

10.   Archeologists found some stone tools, petrified wood and small pieces of obsidian as cutting tools.