伟大的分歧:Ardipithecus ramidus揭示了我们与非洲猿的最后共同祖先的脑后部
C Owen Lovejoy1, Gen Suwa, Scott W Simpson
1Department of Anthropology, School of Biomedical Sciences, Kent State University, Kent, OH 44242-0001, USA. olovejoy@aol.com
Science (New York, N.Y.)
|October 8, 2009
概括
化石证据表明,我们最后的共同祖先与黑猩猩和牛缺乏专门的类似猿类的适应. 现代非洲人猿独立进化了诸如手指节行走之类的特征,而不是从这个祖先那里继承的.
科学领域:
- 古人类学古人类学.
- 进化生物学 进化生物学
- 灵长类动物学 灵长类动物学
背景情况:
- 基因组数据确定了黑猩猩和黑猩猩是人类最近的亲属.
- 基因调节的复杂性限制了使用现存的猿类来推断祖先的解剖学.
- 化石记录在历史上提供了关于早期人类祖先的有限数据.
研究的目的:
- 重建人类和现存的非洲猿类共享的最后一个共同祖先的解剖结构.
- 研究非洲猿类和原始人类特种运动适应的进化起源.
主要方法:
- 对化石记录的分析,特别关注相关的原始人化石.
- 化石证据对现存猿类专业化的比较解剖学评估.
- 推断祖先的特征,基于缺少衍生专业化的关键化石,如Ardipithecus ramidus.
主要成果:
- 来自Ardipithecus ramidus的化石证据表明,最后一个共同祖先缺乏专门的手,脚,骨盆,脊椎和四肢结构,用于悬挂,垂直爬和脚步行.
- 现存的非洲猿类专业化 (悬挂,垂直爬,手指关节行走) 似乎是独立进化的.
- 先进的直立 (直立姿势) 在非洲猿类和原始人类中并行进化.
- 人形脊柱发育使肩带侧向重新定位,没有显著的腰椎缩写.
结论:
- 最后一个共同的祖先很可能拥有普遍的树木登和桥梁能力.
- 现代黑猩猩和大猩猩的专业运动器官解剖学并不代表祖先的状态.
- 这些发现挑战了使用现存的非洲子作为理解人类双脚性起源的模型.
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