在白纪-古世大灭绝期间,四足动物的物种-区域关系跨越了白纪-古世大灭绝
Roger Adam Close1, Bouwe Rutger Reijenga1
1Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, United Kingdom.
概括
大量灭绝重新塑造了物种区域关系 (SARs). 灭绝后的哺乳动物多样化增加了SAR斜率,表明区域多样性更高,与同质化的预期相反.
科学领域:
- 古生物学的古生物学
- 生态生态学 生态生态学
- 进化生物学 进化生物学
背景情况:
- 大规模灭绝是罕见的,具有重大影响生物多样性的灾难性事件.
- 预期的后果包括生物多样性丧失和"灾难类型"的增加,改变物种-区域关系 (SARs).
- 假设表明,SAR斜率和拦截应该在灭绝后减少,但这仍然未经测试.
研究的目的:
- 测试关于白纪-旧世 (K/Pg) 大量灭绝期间SARs变化的假设.
- 调查SAR变异在深度时间多样性动态中的作用.
- 量化北美陆地四足动物在K/Pg事件发生之前,期间和之后的嵌套SARs.
主要方法:
- 利用化石数据重建物种区域关系 (SARs).
- 分析了北美陆地四足动物在坎帕尼亚-伊普斯里亚时间间隔中的SARs,包括K/Pg灭绝.
- 随着时间的推移,SAR斜率和拦截的量化变化.
主要成果:
- 种类-区域关系 (SARs) 呈现出显著的时间变化.
- 灭绝前 (马斯特里希特时代) 的SARS呈现浅坡度,表明贝塔多样性和区域多样性较低.
- 灭绝后的 (丹麦) SARs显示了增加的斜率,由哺乳动物多样化驱动,表明更高的β多样性和区域多样性,与灾难类型的预测相矛盾.
- 后来 (Thanetian-Selandian) 的SAR拦截增加表明了当地和区域多样性动态的异步变化.
结论:
- K/Pg大灭绝导致了物种与区域关系 (SARs) 的重大转变.
- 与预期相反,在灭绝后的早期时期,由于哺乳动物的多样化,区域多样性增加 (较高的SAR斜率),而不是灾难类型的同质化.
- 当地和区域的多样性动态在灭绝事件之后异步演变.
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