Geography of end-Cretaceous marine bivalve extinctions

See allHide authors and affiliations

Science  14 May 1993:
Vol. 260, Issue 5110, pp. 971-973
DOI: 10.1126/science.11537491


Analysis of the end-Cretaceous mass extinction, based on 3514 occurrences of 340 genera of marine bivalves (Mollusca), suggests that extinction intensities were uniformly global; no latitudinal gradients or other geographic patterns are detected. Elevated extinction intensities in some tropical areas are entirely a result of the distribution of one extinct group of highly specialized bivalves, the rudists. When rudists are omitted, intensities at those localities are statistically indistinguishable from those of both the rudist-free tropics and extratropical localities.