31.   Out of this rock people carved their caves with stone tools or wooden sticks.

32.   Part of the evidence is several sites of fossil mammoth bones mixed with stone tools.

33.   Presumably, Clark said, the hominids had made their stone tools elsewhere and traveled with them as they visited good hunting places.

34.   Since both the canal and pond were dug by hand or with crude stone tools, there was likely a small army of diggers at work.

35.   She found stone tools among the ruins, but has yet to determine their approximate age.

36.   The antelope bones contain many V-shaped, irregular gouges, which are characteristic of stone tools used by hominids, Clark said.

37.   The age of the stone tools was estimated by radioactive dating of fossil corals found closest to them.

38.   The building probably served as a workshop for making stone tools and a form of pottery now known as grooved ware.

39.   The fossil was found in sediments with a scattering of crude stone tools, the earliest association between Homo remains and such artifacts.

40.   The Longgupo evidence consists of two teeth attached to a small fragment of lower jaw, one loose tooth and two simple stone tools.