Sea-level change and rock-record bias in the Cretaceous: a problem for extinction and biodiversity studies
Sea-level change and rock-record bias in the Cretaceous: a problem for extinction and biodiversity studies
复制标题
白垩纪海平面变化和岩石记录偏差：灭绝和生物多样性研究的一个问题
作者：
A. Smith;A. Gale;N. Monks
海洋生物大灭绝与中生代海平面升降变化之间的联系是有据可查的，但令人困惑，因为海平面变化实际上可能导致大灭绝似乎是不可信的。然而，海平面变化的大规模周期可以而且确实改变了区域和全球岩石记录中保存的浅海与深海大陆架沉积物的比例。这种埋藏的巨型生物本身就可能是第一次和最后一次发生和常设多样性的驱动模式，因为多样性和保护潜力都随着水深而变化。我们表明，在西欧的Cenomanian/Turonian动物群事件的所有预测的签名预期，如果taphonomic megabias的原因。级类群终止于假灭绝和拉撒路类群主要发现在岸上相，从岩石记录消失了很长一段时间。在其他大规模的灭绝被认为是表面价值之前，需要对岩石记录中的偏差进行更仔细的分析，并且需要在系统发育框架内分析动物群的消失。
Abstract The association between mass extinction in the marine realm and eustatic sea-level change in the Mesozoic is well documented, but perplexing, because it seems implausible that sea-level change could actually cause a major extinction. However, large-scale cycles of sea-level change can and do alter the ratio of shallow to deep marine continental-shelf deposits preserved in the rock record both regionally and globally. This taphonomic megabias alone could be driving patterns of first and last occurrence and standing diversity because diversity and preservation potential both change predictably with water depth. We show that the Cenomanian/Turonian faunal event in western Europe has all the predicted signatures expected if taphonomic megabias was the cause. Grade taxa terminating in pseudoextinction and Lazarus taxa are predominantly found in the onshore facies that disappear for extended periods from the rock record. Before other mass extinctions are taken at face value, a much more careful analysis of biases in the rock record needs to be carried out, and faunal disappearances need to be analyzed within a phylogenetic framework.