概括
沙斯塔地面惰动物的放射性碳测年揭示了亚利桑那州从4万到11000年前的占领. 灭绝与克洛维斯猎人一致,支持过度杀戮的假设.
科学领域:
- 古生物学的古生物学
- 通过放射性碳测年法进行测年.
- 考古学的考古学
背景情况:
- 有机遗骸,特别是便,对于放射性碳测年已灭绝的大型动物有价值.
- 之前的研究已经确定了地面惰动物在不同地区的存在.
研究的目的:
- 为了确定沙斯塔地在亚利桑那州兰帕特洞穴的占用时间表.
- 为了将地面的灭绝时间与克洛维斯大游戏猎人的存在联系起来.
主要方法:
- 有机物质 () 的放射性碳年代测定来自亚利桑那州兰巴特洞穴.
- 分析来自其他西南洞穴和南美洲的地面惰动物遗骸.
主要成果:
- 从4万多年前到1万1千年前,沙斯塔地在兰帕特洞穴的定期居住.
- 在西南地区,地面的灭绝发生在克洛维斯时期后不久.
- 南美洲的地面惰动物遗骸被发现稍微年轻一些.
结论:
- 沙斯塔地的灭绝与"爆炸性过度杀戮"模型一致.
- 人类的狩猎压力可能对地面的灭绝做出了重大贡献.
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