一个大象大小的三叠纪晚期突触体
Tomasz Sulej1, Grzegorz Niedźwiedzki2
1Institute of Paleobiology, Polish Academy of Sciences (PAS), Twarda 51/55, 00-818 Warsaw, Poland.
概括
巨大的二动物,Lisowicia bojani,来自三纪晚期,达到9,挑战了关于三纪大草食动物进化的先前观点. 这一发现揭示了早期的哺乳动物获得了以前被认为是恐龙独有的巨大尺寸.
科学领域:
- 古生物学
- 脊椎动物的进化
- 中生代生态系统
背景情况:
- 在三叠纪时期,二龙是一种多样化的类动物群.
- 以前的理解表明,只有恐龙在三叠纪晚期才达到巨大的陆地草食体型.
- 在三叠纪,非恐龙类陆地四足动物的上限被认为比大型恐龙要小得多.
研究的目的:
- 描述一个新发现的巨型二动物,
- 分析Lisowicia bojani的大小和生长模式的古生物学和进化影响.
- 重新评估突触类动物,特别是干群哺乳动物在三叠纪大草食生物辐射中的作用.
主要方法:
- 对Lisowicia bojani的化石描述和骨质学分析
- 基于化石遗骸的身体大小 (长度,高度,质量) 的估计.
- 肢体骨皮质的组织学检查和停止生长线 (LAG) 的分析,以推断生长速度.
主要成果:
- 据估计,Lisowicia bojani是一个巨大的突触体,长4.5米,高2.6米.
- 它代表了已知最年轻的无可争议的二动物和最大的非恐龙陆地四足动物.
- 证据表明永久的快速生长,类似于恐龙和哺乳动物,由缺乏LAG和高度重塑的骨皮质表明.
结论:
- 发现Lisowicia bojani颠覆了在三叠纪时期只有恐龙才能达到大草食者的地位的观点.
- 它表明干群哺乳动物 (二龙) 能够达到哺乳动物进化中未见过的体型.
- 这一发现显著扩大了我们对三叠纪大草食生物多样性的理解, 以及类动物的进化能力.
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