| Aha! | |
| Making Stone Age Tools | |
| Human beings first made tools in the Old Stone Age. | |
| You may think making a stone tool would be easy. | |
| Dietrich Stout, an anthropology professor | |
| at Emory University, wrote in the journal | |
| Scientific American that making | |
| a hand axe took him 300 hours. | |
| Professor Stout monitored his brain activity | |
| during the tool-making process. | |
| He said that human beings may have developed | |
| communication skills by talking to | |
| each other when they made stone tools. |
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