Long-distance dispersal and the reef-building corals of the Eastern Pacific

It is currently widely accepted that the hermatypic coral fauna in the Eastern Pacific Ocean underwent massive extinction during the mid-Tertiary, with subsequent transoceanic colonizatiion by planulae from the Indo-West Pacific region during periods of favorable conditions. We suggest that the available evidence does not strongly support this biogeographic hypothesis; moreover, we contend that it is untestable in its present form. In its place we propose an alternative hypothesis based upon modification of a previously widespread, pan-Tethyan coral biota which has since been modified by tectonic events, speciations, and extinctions.Order of authorship was determined by the toss of a coin.