来自中国成江矿床的祖先皮动物
D-G Shu1, S Conway Morris, J Han
1School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China. elidgshu@nwu.edu.cn
Nature
|July 23, 2004
概括
在中国发现的化石揭示了新的早期双胞胎体组,即白囊类. 这些化石提供了关于deuterostomes的进化历史的见解,包括原始皮动物.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 动物学 动物学
背景情况:
- 双体体代表着一个多样化的超级系,包括带状动物,皮动物和半带状动物.
- 最近的分子数据稳定了deuterostome的基因组,但灭绝的中间形式的进化序列仍然不清楚.
- 具有特殊软部份保存的化石记录对于了解早期deuterostome进化至关重要.
研究的目的:
- 描述一个新发现的一组早期deuterostomes,vetulocystids,从中国的坎布里亚沉积物.
- 通过比较它们的形态与已知的deuterostome群体来调查vetulocystids的遗传学位置.
- 为了有助于了解早期deuterostome进化和现存群体的起源.
主要方法:
- 在中国西南部挖掘和分析化石矿床.
- 对新发现的标本进行了详细的形态检查.
- 与现有的deuterostome种群进行比较的基因分析,包括 vetulicolians,yunnanozoans和homalozoans.
主要成果:
- 发现和描述一组新的早期双胞胎体,称为vetulocystids.
- 鉴定了白细胞体和白细胞体之间的形态相似之处.
- 观察了囊动物和同类动物之间的相似之处,这是一个有争议的原始皮动物群.
结论:
- 长囊体体在早期的双体进化中代表着一个重要的新分类.
- 这些发现为解决同类动物的遗传位置提供了新的数据.
- 这一发现增强了我们对坎布里亚时代中乳腺体多样化的理解.
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