Chronocorrelation of the late paleozoic to triassis world: a time of climate and biodiversity change

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Demonstrating the time equivalence of events, or chronocorrelation, involves all available means including biostratigraphy, numerical dating, remanent magnetism and geochemical signatures. Chronocorrelation of the Late Paleozoic and Triassic (355 to 200 million years ago) has immediate relevance to changes we are witnessing today on Planet Earth, including climate change and dramatic changes in biodiversity. Understanding the detailed dynamics that led to climate changes and biodiversity collapse will demand high resolution and temporal precision and the collaborative efforts of a community of geoscientists. This project is part of that effort and largely aimed at producing biostratigraphic (temporal) control using conodonts. Conodonts were an eel-like animal whose only hard parts included microscopic teeth. The rapid evolution of this extinct group is represented by distinct changes in form of the teeth. The relevance and significance of this research is indisputable; many of the changes we are experiencing or anticipating today are foreshadowed by events that occurred during the Late Paleozoic and Triassic. The Pennsylvanian and Early Permian were witness to periods of glacial and interglacial events resulting in rapid sea-level changes, an issue particularly relevant in today's discussions of the consequences of potential global warming. During the Early Permian plate tectonics brought a series of continental fragments together as a giant supercontinent (Pangea), resulting in the increase of aridity in much of the continental interior, another concern of modern climate change as we continue to see record temperatures over much of the planet. All of these factors contributed toward an ecologic collapse and major extinction, particularly near the end of the Permian - an extinction often referred to as the greatest extinction in Earth's history (95% of species). The Triassic began as a desolate world nearly barren of life, but during a recovery interval, life began to diversify again in a series of pulses. Today we are living during an interglacial period that has seen profound changes in climate and biodiversity. What will the future bring? Better understanding the timing of past events may provide an answer.