- © 2003 Cambridge University Press
Look in any textbook at the curves of changing overall biodiversity through the Phanerozoic and two impressive bursts of taxonomic proliferation are immediately apparent. The first occurs through the Ordovician checked by the end-of-period mass extinction and the second is more long-winded, running from the Mid Mesozoic and through the Cenozoic. But what are the underlying patterns? This compilation of 14 papers which were originally presented as part of the Lyell Meeting in 2001 deals with a variety of aspects of these radiations.
The editors, Owen & Crame, provide a useful overview of the scope of the volume and highlight the nature of the problems and the types of questions posed by those seeking to get to grips with these periods of proliferating biodiversity. Chief amongst these: Why did these dramatic events occur? What was the trigger? Are there similarities between the two? How ‘real’ was the Mesozoic burst? Owen & Crame point out that both the Ordovician and Mesozoic–Cenozoic increases in biodiversity occur at times when there is an increase in provincialism associated with fragmentation of the continents, sea level rises and climatic change.
The Ordovician radiation affected organisms at a variety of taxonomic levels, from species to class, and put into place the classic ‘Palaeozoic Evolutionary Fauna’. The first half of the book is largely devoted to papers investigating the effects of this radiation, particularly on …