Fossil record

The fossil record is incomplete, so a history of biodiversity reconstructed simply by adding up the species or higher taxa that are preserved at different places and times in the fossil record is likely to be incorrect and misleading. One must also consider the effect of variation in space, time, and among organisms on the probability of a particular organism being preserved as a fossil and subsequently sampled by paleontologists. This article summarizes some of the principal causes of such variation, and the techniques employed to try to account for their distorting effects on apparent biodiversity