<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区
          US EUROPE AFRICA ASIA 中文
          China / World

          Recreating old weapons for new discoveries of human history

          (China Daily) Updated: 2017-07-14 09:16

          OHIO, United States - Metin Eren wasn't satisfied just digging up ancient arrowheads to learn about the past. He wanted to use them for their intended purpose.

          But shooting and shattering priceless millennia-old tips is out of the question, so instead, the archaeologist chips replicas of the stone-age weapons by hand.

          "We can break 'em and throw 'em," he says. "Our imagination is the limit."

          The 34-year-old professor at Kent State University, in Ohio in the United States, specializes in experimental archaeology recreating ancient pots, knives and arrows. By testing the replicas in ways impossible with the originals, archaeologists study how tools found in archaeological digs were actually used.

          "The stuff that we find, it's just stuff," says Brian Andrews, an archaeologist at Rogers State University. "Stuff's cool, but we're not interested in stuff for the sake of itself. We're interested in the human behaviors that went into making it."

          Eren's experiments focus on making sense of ancient weapons littered across the Americas, illustrating how humans first settled the Western Hemisphere: through careful preparation, long-term planning, and refined technology.

          "Even though it's the Stone Age, they're still thinking in a very modern way," Eren says.

          Already he has cracked one longtime mystery. In the early 1900s, archaeologists found unusually shaped arrowheads in North America, with grooves carved from the base halfway to the head's tip. They first appeared over 13,000 years ago and spread rapidly across the continent, but existed nowhere else. Researchers were puzzled why the grooves were carved, with speculation running from religious rituals to mere decoration.

          That's where experimental archaeology came in. By testing the pressure at which the arrowheads would crack using a crusher and computer models, Eren discovered the grooves act as a shock absorber. It allows the arrowhead's thinned base to crumple slightly and absorb energy upon the arrow's impact, making the head less likely to break.

          Archaeologists call it the "first truly American invention".

          On a Thursday morning, Eren gingerly examined a sliver of obsidian. Such blades are "sharp to the molecule," he said, and one nearly sliced off his left pinkie in graduate school.

          In his hand, he's holding a piece of the puzzle of how humans came to rule the world. By refining their weapons, ancient Americans learned how to adapt to all sorts of conditions.

          "They knew they were going into unknown territory, and because of that they actually prepared extremely well technologically," Eren said. "Understanding this process of colonization is important to understanding how we are today."

          Associated Press

          Recreating old weapons for new discoveries of human history

          Highlights
          Hot Topics

          ...
          主站蜘蛛池模板: 九九热在线精品视频99| 亚洲色欲在线播放一区| 亚洲精品一区二区区别| 中文字幕乱码免费人妻av| 国产国产人免费人成免费| 国产亚洲制服免视频| 欧美日韩视频综合一区无弹窗| 99亚洲男女激情在线观看| 国产日韩欧美黄色片免费观看| 国产精品视频白浆免费视频| 人妻少妇不满足中文字幕| 国产乱色国产精品免费视频| 97人人添人人澡人人澡人人澡| 久久久喷潮一区二区三区| 94人妻少妇偷人精品| 亚洲国产精品13p| 日本一区二区三区黄色网| 久久久久青草线蕉亚洲| 久热这里有精品免费视频| 激情自拍校园春色中文| 国内少妇人妻偷人精品视频| 丰满少妇69激情啪啪无| 日本二区三区视频免费观看| 国内永久福利在线视频图片| 久久天天躁夜夜躁狠狠躁2022| 強壮公弄得我次次高潮A片| 日韩av无码久久精品免费| 国产99精品成人午夜在线| 色偷偷女人的天堂亚洲网| 亚洲精品一区二区三区大桥未久 | a级黑人大硬长爽猛出猛进| 产国语一级特黄aa大片| 国产成人精品久久一区二区| 亚洲国产欧美在线人成| 久久夜色噜噜噜亚洲av| 他掀开裙子把舌头伸进去添视频| 国产精品久久久久久久久久直播| 在线观看成人永久免费网站 | 香蕉eeww99国产在线观看| 免费人成再在线观看视频| 伊人狠狠色j香婷婷综合|