Add Yahoo as a preferred source to see more of our stories on Google. NASA's Curiosity rover has encountered patches of sharp “gator-back” rocks causing mission planners to look for a new route to ...
Sharp stone technology chipped over three million years allowed early humans to exploit animal and plant food resources. But how did the production of stone tools -- called 'knapping' -- start?
Some results have been hidden because they may be inaccessible to you
Show inaccessible results