Bayerische Staatssammlung für Paläontologie und Geologie, Richard-Wagner-Straße 10, 80333 Munich, Germany.
Proc Biol Sci. 2011 Apr 22;278(1709):1165-70. doi: 10.1098/rspb.2010.1754. Epub 2010 Sep 29.
The fossil record is our primary window onto the diversification of ancient life, but there are widespread concerns that sampling biases may distort observed palaeodiversity counts. Such concerns have been reinforced by numerous studies that found correlations between measures of sampling intensity and observed diversity. However, correlation does not necessarily mean that sampling controls observed diversity: an alternative view is that both sampling and diversity may be driven by some common factor (e.g. variation in continental flooding driven by sea level). The latter is known as the 'common cause' hypothesis. Here, we present quantitative analyses of the relationships between dinosaur diversity, sampling of the dinosaur fossil record, and changes in continental flooding and sea level, providing new insights into terrestrial common cause. Although raw data show significant correlations between continental flooding/sea level and both observed diversity and sampling, these correlations do not survive detrending or removal of short-term autocorrelation. By contrast, the strong correlation between diversity and sampling is robust to various data transformations. Correlations between continental flooding/sea level and taxic diversity/sampling result from a shared upward trend in all data series, and short-term changes in continental flooding/sea level and diversity/sampling do not correlate. The hypothesis that global dinosaur diversity is tied to sea-level fluctuations is poorly supported, and terrestrial common cause is unsubstantiated as currently conceived. Instead, we consider variation in sampling to be the preferred null hypothesis for short-term diversity variation in the Mesozoic terrestrial realm.
化石记录是我们了解古代生命多样化的主要窗口，但人们普遍担心采样偏差可能会扭曲观察到的古生物多样性计数。许多研究发现采样强度和观察到的多样性之间存在相关性，这进一步加剧了人们的担忧。然而，相关性并不一定意味着采样控制了观察到的多样性：另一种观点认为，采样和多样性可能都受到某些共同因素的驱动（例如海平面驱动的大陆洪水变化）。后者被称为“共同原因”假说。在这里，我们对恐龙多样性、恐龙化石记录的采样以及大陆洪水和海平面变化之间的关系进行了定量分析，为陆地共同原因提供了新的见解。尽管原始数据显示大陆洪水/海平面与观察到的多样性和采样之间存在显著相关性，但这些相关性在去除趋势或消除短期自相关后并不存在。相比之下，多样性和采样之间的强相关性在各种数据转换后仍然存在。大陆洪水/海平面与分类多样性/采样之间的相关性源于所有数据系列中共同的上升趋势，而大陆洪水/海平面和多样性/采样的短期变化之间没有相关性。全球恐龙多样性与海平面波动相关的假设得到的支持很少，而且目前所设想的陆地共同原因是没有根据的。相反，我们认为，在中生代陆地领域，采样变化是短期多样性变化的首选零假设。
