化石化过程和我们对动物古代的解读
Ross P Anderson1, Christina R Woltz2, Nicholas J Tosca3
1Department of Earth Sciences, University of Oxford, Oxford, OX1 3AN, UK; All Souls College, University of Oxford, Oxford, OX1 4AL, UK.
Trends in ecology & evolution
|June 29, 2023
概括
分子时钟表明动物在8亿年前进化,但化石只出现在57.4亿年前. 这项研究发现化石化条件,而不是动物进化,解释了这一差距,表明早期动物古代的软最大约束.
科学领域:
- 古生物学的古生物学
- 地质时间学 (Geochronology)
- 进化生物学 进化生物学
背景情况:
- 对于冠状动物的起源,分子钟估计 (约8亿年前) 和化石记录 (约5.74亿年前) 之间存在重大差异.
- 语音学偏见,例如缺乏小型或软体生物的保存条件,经常被认为是这种差距的原因.
研究的目的:
- 为了调查塔法诺米在分子钟和早期动物进化的化石基础估计之间的感知断开中扮演的角色.
- 为了比较新新生代的化石化过程与坎布里亚时期的化石化过程,坎布里亚时期有丰富的动物化石.
主要方法:
- 在新新生代和坎布里亚时代沉积岩中化石化过程的比较分析.
- 检查与伯吉斯页岩类型 (BST) 保存和新新生代化石发生相关的泥石中的矿物学.
主要成果:
- 坎布里亚 BST 保存与一系列特定的泥石矿物学有关.
- 新新生代化石泥石很少与BST沉积物具有相同的矿物质.
- 在超过7.89亿年前的沉积物中没有动物化石,在这些沉积物中满足了BST保存条件.
结论:
- 矿物学和保存风格的观察到的差异表明分音学因素,不一定是以后的进化起源,解释了早期动物化石的稀缺性.
- 数据表明动物古代的软最大约束,这意味着虽然动物可能早些时候存在过,但它们的化石化条件直到晚些时候才满足.
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