来自东非的新型人类属显示出多样化的中纪血统
M G Leakey1, F Spoor, F H Brown
1Division of Palaeontology, National Museums of Kenya, P.O. Box 40658, Nairobi, Kenya. meave@swiftkenya.com
Nature
|March 22, 2001
概括
来自肯尼亚的新型人类化石揭示了比以前想象的更大程度的多样性. 这些发现挑战了早期人类进化的现有模型,并表明早期的适应性辐射是由饮食驱动的.
科学领域:
- 古人类学古人类学.
- 人类进化人类进化
- 化石发现 化石发现
背景情况:
- 目前对早期原始人族系的理解集中在澳大利亚甲虫 (Australopithecus afarensis) 身上,作为普略纪早期到中期的单一祖先血统.
- 人们认为,这种血统仅在普略纪晚期才产生了多样化的原始人种类.
- 之前的解释表明,在普略纪中期,人类的分类学多样性有限.
研究的目的:
- 报道肯尼亚图尔卡纳湖西部新发现的原始人化石.
- 为了研究平生代中期人类的分类学多样性.
- 根据新的化石证据,重新评估早期人类的原始物种.
主要方法:
- 发现和分析新的人类化石,包括一个350万年前的头骨.
- 对化石形态学与当代人类物种的比较分析,特别是澳大拉皮铁克斯阿法伦西斯.
- 评估牙特征及其与进化适应的关联.
主要成果:
- 发现的化石与Australopithecus afarensis相比呈现出明显的特征,这表明在普略纪中期,人类的分类学多样性很大.
- 一个有350万年历史的头骨呈现出独特的面部特征和原始神经头骨特征的组合.
- 这个头骨被分配到一个新的类型的人类,强调了扩大的多样性.
结论:
- 人类的分类学多样性比以前认可的更远地延伸到中纪.
- 这些发现表明,在人类血统中,早期的饮食驱动的适应性辐射存在.
- 这些发现需要对Plio-Pleistocene hominin原始物和牙特征关联的修订理解.
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