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Tiktaalik roseae at the Academy of Natural Sciences of Philadelphia

Paleontological research occasionally reveals species with far-reaching consequences for reconstructing the tree of life and exploring the processes that shaped the diversity of life on Earth. Concurrent with the release of this volume of the Proceedings of the Academy of Natural Sciences, the research group at the Academy said farewell to a suite of fossils that have modernized our understanding of the “fish-to-tetrapod” transition. Over the past 15 years, a project co-led by the Academy’s Ted Daeschler and Neil Shubin of the University of Chicago has endeavored to discover Late Devonian vertebrate fossils from the Nunavut Territory of Arctic Canada. Their ultimate goal was realized in 2004 and subsequent field seasons with the collection and description of the tetrapodomorph sarcopterygian, Tiktaalik roseae, now recognized as belonging to the sister group of Tetrapoda.