Jared Diamond in Guns, Germs, and Steel characterizes the Great Leap Forward as starting around 100,000-50,000 years ago. He particularly names the development and use of tools as being the achievements of the Great Leap Forward. Specifically, archeologists have discovered stone tools in East African sites that date back to this period, along with jewelry artifacts made of ostrich-shell beads. Similar artifacts dating back to this period were also found in the Near East, and both southeastern and southwestern Europe. Particularly in southwestern Europe, along with the discovery of "fully modern skeletons" called Cro-Magnons, various tools were found in garbage sites, including stone tools, tools made of bone that were useful as fishing hooks, and other tools that were obviously used as "needles, awls, and engraving tools" (p. 40). In addition, tools made of multiple pieces were also found in the garbage sites, specifically used as weapons, such as harpoons, spear-throwers, and bows and arrows. The development of weaponry led to the ability to hunt larger game, such as elephants. Other evidence shows that further inventions were developed, such as rope to make nets, lines, and snares for fishing and catching birds. There are also signs of the development of houses and clothing for better survival in harsher climates. Other artifacts show the development of a sense of aesthetics, such as remains of jewelry, cave paintings, statues, and musical instruments. Hence, as the author argues, all of these inventions of tools, weapons, jewelry, and art are examples of achievements made during the Great Leap Forward.