来自巴塔哥尼亚的大白时期的形龙提供了洞察力,了解类恐龙在冈德瓦纳的进化
Sebastián Apesteguía1, Fernando E Novas
1Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Av. Angel Gallardo 470, Buenos Aires (1405), Argentina. paleoninja@yahoo.com.ar
Nature
|October 10, 2003
概括
在巴塔哥尼亚发现的一种新的虫爬行动物Priosphenodon avelasi揭示了虫在白纪晚期的生态系统中丰富. 这一发现表明,它们被所取代的时间被推迟到三级早期.
科学领域:
- 古生物学的古生物学
- 脊椎动物古生物学 脊椎动物古生物学
- 中生代生态系统 中生代生态系统
背景情况:
- 斯芬顿的爬行动物在三纪和罗纪是多样化的,但在白纪显著下降.
- 稀少的早期白纪化石记录表明,虫的多样性下降,被认为是生态继承者.
- 以前的理解表明,在三级时期之前,牙动物几乎灭绝了.
研究的目的:
- 描述一个新的sphenodontian属和物种,Priosphenodon avelasi,来自巴塔哥尼亚的白纪晚期.
- 重新评估白纪时期形动物的生态作用和丰富性.
- 为了研究形体动物被形体动物生态替代的时间.
主要方法:
- 古生物学发掘和发现了许多Priosphenodon avelasi的骨.
- 化石标本的比较解剖学分析.
- 在巴塔哥尼亚的Candeleros形成的平流图和古生态评估.
主要成果:
- 在Cenomanian-Turonian Candeleros形成中发现了丰富的Priosphenodon avelasi,一个大型的sphenodontian (长达1米),在Cenomanian-Turonian Candeleros形成中.
- 普里奥斯诺顿·阿维拉西 (Priosphenodon avelasi) 是化石地点最丰富的四足动物,数量超过其他群体,如恐龙和哺乳动物.
- 这一发现挑战了在南美洲的白纪期间形动物衰落的概念.
结论:
- 由Priosphenodon avelasi代表的Sphenodontians是白纪晚期南美陆地生态系统的重要组成部分.
- 虫 (虫和蛇) 对虫的生态继承可能比以前认为的晚些时候发生,可能是在三级早期.
- 这一发现有助于填补早期白纪和它们的现代亲戚之间的形动物化石记录中的一个显著的空白.
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