Devonian Climate, Sea Level and Evolutionary Events

The geological and palaeontological records of climate change and evolutionary events reflect Earth’s widely fluctuating climate systems. Past climates hold the clues to understanding future developments. In this context, research on linked climate, biodiversity and sea-level fluctuations of the Devonian contributes to the general knowledge of deep-time climate dynamics. A fruitful co-operation between the International Geoscience Programme IGCP 596 and the International Subcommission on Devonian Stratigraphy (SDS) addressed the complex succession of climate-linked Devonian global events of varying magnitude. The primary goal of IGCP 596 was to assess mid-Palaeozoic climate changes and their impact on marine and terrestrial biodiversity using an interdisciplinary approach. The focus of SDS includes a revision of the eustatic sea-level curve and the integration of refined chrono- and biostratigraphy with modern chemo-, magneto-, cyclo-, event- and sequence stratigraphy. This enabled the much improved dating and correlation of abiotic perturbations, evolutionary changes, organism and ecosystem ranges. Results by 37 authors are presented in 14 chapters, which cover the entire Devonian.
Famennian survivor turiniid thelodonts of North and East Gondwana
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Published:January 01, 2016
Abstract
Microvertebrate samples from the Upper Devonian Hojedk section, southeastern Iran, and the Napier Formation, northwestern Australia, have yielded scales of agnathan thelodonts, dated as early/mid-Famennian (crepida–marginifera/trachytera conodont zones). These scales are referred to Arianalepis megacostata, a new genus and species, and Arianalepis sp. indet., a second indeterminate species of this new turiniid genus. Further recorded scales of Australolepis seddoni from the Napier Formation confirm the age range for this taxon as extending into the late Frasnian. The new remains post-date the previously youngest thelodonts from Iran and Western Australia and provide the first evidence of thelodonts surviving...