巨型四足动物是刚果岛的顶级捕食者
Claudia A Marsicano1,2, Jason D Pardo3, Roger M H Smith4,5
1Universidad de Buenos Aires, FCEN, Departamento de Cs. Geológicas, Buenos Aires, Argentina. claumar@gl.fcen.uba.ar.
Nature
|July 3, 2024
概括
在纳米比亚发现了一种新的巨型四足动物化石, 挑战了早期四足动物进化论. 这一发现表明,大陆四足动物在石灰岩到波斯时期的过渡期中分布更广泛.
科学领域:
- 古生物学
- 进化生物学
- 脊椎动物古生物学
背景情况:
- 目前的假设将早期四足动物的进化与石灰岩时期的赤道湿地联系起来.
- 支持这些假设的化石记录在很大程度上局限于古方位的潘盖亚 (Laurussia).
- 之前的模型表明,在石灰岩纪晚期,动物的转移和扩散速度很快.
研究的目的:
- 描述一个新的巨型四足动物化石从高度的早期珀米亚沉积.
- 挑战关于四足动物早期分布和进化的现有假设.
- 为大陆四足动物的全球分布提供证据.
主要方法:
- 化石遗骸描述:包括头骨和骨的Gaiasia jennyae.
- 为了确定盖亚西亚的进化地位,
- 古地理重建和与现有化石数据进行比较.
主要成果:
- 发现了Gaiasia jennyae,这是一个来自纳米比亚 (55°S) 早期波斯纪 (280万年前) 的大型四足动物.
- 盖亚西亚表现出独特的头骨特征:骨薄弱,钻石形状,牙扩大.
- 遗传学分析将盖亚西亚定位为碳化类的姐妹分类.
- 盖亚西亚是目前已知的最大的数位干四足动物,表明它在冈多瓦冷温地带存在.
结论:
- 在高度的贡德瓦纳发现了盖亚西亚,挑战了早期四足动物进化的赤道中心观点.
- 大陆四足动物在石灰岩 - 珀米亚过渡时期在不同的古气候区域建立.
- 目前关于四足动物的全球周转和分散的假设需要修订,以纳入高度数据.
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