北美末纪恐龙化石记录的结构
Christopher D Dean1, Alfio Alessandro Chiarenza1, Jeffrey W Doser2
1Department of Earth Sciences, University College London, 5 Gower Place, London WC1E 6BS, UK.
Current biology : CB
|April 9, 2025
概括
恐龙灭绝模式在新的贝叶斯模型中更加清晰. 占用模型显示,在灭绝之前,恐龙数量稳定,而不是下降,这挑战了以前对化石记录的解释.
科学领域:
- 古生物学的古生物学.
- 古生物学的古生物学
- 地质科学 地质科学
背景情况:
- 在6600万年前灭绝之前,非鸟类恐龙的衰退是有争议的,因为化石数据不一致.
- 在恐龙化石记录中区分真正的生物学趋势与采样偏差是具有挑战性的.
研究的目的:
- 量化偏差并了解恐龙化石记录的结构.
- 通过一种新的建模方法,估计北美白纪晚期的恐龙占用率和发现概率.
主要方法:
- 古气候,地理和化石数据的整合.
- 应用贝叶斯式占用率建模框架.
- 同时估计恐龙占用率和检测概率.
主要成果:
- 模拟的恐龙占地在整个白纪晚期保持稳定,与原始化石数据明显下降相反.
- 检测概率降低,而不是占用率降低,解释了明显的下降,受地质浮标面积和土地覆盖面积的影响.
- 由于地质记录偏差,传统的多样性估计可能不准确.
结论:
- 贝叶斯占用模型为分析古生物学数据提供了一个强大的方法.
- 这项研究强调了化石记录中的重大偏差,影响了对恐龙种群动态的解释.
- 在白纪-古纪灭绝事件之前,恐龙种群很可能是稳定的,而不是下降的.
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