Plants and Marine Organisms Across the K/T Boundary
I approach the mysteries of the K/T extinctions unrepentantly from the perspective of the vertebrate fossil record. These are the animals I know best. As a vertebrate paleontologist I am also painfully aware of instances in which scientists who are not vertebrate paleontologists fail to fully deal with or even misconstrue what the vertebrate fossils across the K/T boundary actually say--and, just as important, on what issues the fossils are silent. Theories of extinction must ultimately stand, fall, or at least be revised based upon how well they explain patterns of biotic turnover. Simple counts of the percentages of extinction or survival in various taxa do not constitute a test of a theory's veracity.
So far, I have gone through who the vertebrate players were, what their pattern of turnover was at the K/T boundary, and how well these patterns support corollaries of the impact, volcanism, and marine regression theories, plus two "corollaries without a cause": local wildfires and the detrital influx hypothesis. Is there a possibility that, as I have hinted, the K/T extinctions were not the outcome of a single horrific cause but rather the result of a cacophony of causes that ushered in the biotic changes that distinguish what has come to be known as the K/T boundary? I will explore this issue in the final chapter. But first I must recount, if all too briefly, the turnover patterns at the K/T boundary of taxa about which I am not an expert--notably, plants and