一个特里亚斯纪水生原恐龙,子极其长
Chun Li1, Olivier Rieppel, Michael C LaBarbera
1Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), Chinese Academy of Sciences, Post Office Box 643, Beijing 100044, China. lichun@pa.ivpp.ac.cn
Science (New York, N.Y.)
|September 28, 2004
概括
一种新发现的长海洋爬行动物,Dinocephalosaurus,来自三叠纪中期,提供了完全水生原始龙的证据. 它的长长的子可能有助于古代海洋的养效率.
科学领域:
- 古生物学的古生物学
- 海洋生物学 海洋生物学
- 脊椎动物动物学 脊椎动物动物学
背景情况:
- 爬行动物系在中纪期间在浅海环境中多样化.
- 从西方泰提斯 (Tethys) 已知的原始类爬行动物Tanystropheus的长度达到5-6米.
研究的目的:
- 为了报道发现了一种新的长化石,Dinocephalosaurus.
- 为了提供一个完全水生原始龙的证据.
- 为了研究其极度延长的子的适应意义.
主要方法:
- 化石发现和海洋沉积物的分析.
- 对Dinocephalosaurus进行比较解剖研究.
- 古生态环境重建.
主要成果:
- 恐龙头类动物是在中国西南部的三叠纪中期海洋沉积物中发现的,大约有2.3亿年的历史.
- 这种分类单元被明确地确定为完全水生原始龙.
- 极度延长的子的Dinocephalosaurus被解释为一个适应水生生物.
结论:
- 恐龙头类动物 (Dinocephalosaurus) 代表了一种完全水生前类动物的第一个明确证据.
- 独特的部形态表明适应在海洋环境中提高养效率.
- 这一发现扩大了我们对中生代海洋生态系统爬行动物多样化和适应性的理解.
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