Abstract

As early as 1972 the noted palaeobiologist David Raup suggested that estimates of palaeobiodiversity – the changing number of species over geological time – may be more apparent than real as they closely tracked that of available rock. However, in the subsequent 30 years most palaeobiologists interpreted their diversity curves at face value. It wasn’t until the last decade that the problem of potential bias was revisited, this time with more sophisticated data and methods. Strong correlations between palaeobiodiversity and proxies for either sampling or rock volume were frequently found, although their interpretation remains contentious. Here I show that a sampling bias explanation for some palaeobiodiversity patterns is inescapable.