WHO MAKES IT TO REDEMPTION ISLAND? AN EXAMINATION OF TAXONOMIC RECOVERY AFTER THE END-PERMIAN MASS EXTINCTION

Taxonomic recovery is not as straightforward as the diversification of new species and migration of surviving species into vacated niches –particularly with the end-Permian mass extinction. To gain further understanding of taxonomic recovery and it affects on the development of the marine Mesozoic revolution it would be helpful to determine which taxa participate in recovery diversification and which taxa do not participate. I examined the taxonomic range data of organisms present within the Late Permian, Early Triassic, and Middle Triassic intervals and differentiated the organisms as “Survivor”, “Recovery” or “Extinction” taxa. Survivor taxa are defined as organisms originating prior to the mass extinction or in the Early Triassic and then disappear. Recovery taxa are defined as organisms that originate before the extinction or in the Early or Middle Triassic and continue to the Late Triassic and beyond. Initial results of only the dominant taxa are not too surprising: the majority of the bivalves, cephalopods, corals, and gastropods constitute recovery taxa mostly originating from the Paleozoic with exception of the coral taxa who originate in the Triassic. The majority of brachiopods constitute extinction taxa all originating in the Paleozoic. In terms of longevity, the majority of recovery taxa all extend into the Jurassic and beyond. At present it is speculated that perhaps the vacating of the previous incumbent (i.e., brachiopod taxa) might have help long-lived Paleozoic taxa to recovery but more data still need to be analyzed to truly test this idea. It is also expected that more survivor taxa will be identified as the less dominant taxa are analyzed and added to the study.