![]() ![]() occidentalis are indistinguishable from the living species. With few exceptions, the bulk of the Metasequoia fossils described in the literature indicate that the fossils assigned to M. ![]() The pronounced reduction in distribution during the Miocene appears to be coupled with increasing global aridity and cooling and increased competition for resources and habitat from representatives of the Pinaceae. Following the apparent early Pleistocene extinction, Metasequoia re-appeared in southeastern China. Metasequoia persisted in western Siberia and the Canadian Arctic until late Pliocene time, and in western Georgia and Japan until the late Pliocene-early Pleistocene. Of particular interest is the apparent lack of Metasequoia fossils in Europe despite the presence of two land bridges linking North America and Europe throughout the early Tertiary and the drying of the Turgai Straits that separated eastern and western Asia up until Oligocene time. More importantly, the distribution of Metasequoia indicates that the genus grew and reproduced under a diverse range of climatic and environmental conditions throughout geologic time, including the cold and unique lighting conditions of the polar latitudes. By the early Tertiary, the distribution patterns do not appear to have changed considerably from that seen during the Late Cretaceous, except that Metasequoia became a dominant constituent of the polar Broad-leaved Deciduous Forests. However, if the inter-continental exchange of the early representatives of this genus occurred prior to the establishment of Beringia, migration would have still been possible across the Spitsbergen Corridor, which was functional during the Early Cretaceous. Exchange of Metasequoia between Asia and North America probably occurred across Beringia, which had become functional at the Albian-Cenomanian boundary (ca. ![]() The genus first appears in Cenomanian age deposits from western Canada, Alaska and the Arkagala and Koylma River basins in Russia and indicates that Metasequoia had achieved a wide distribution early in its evolutionary history. The fossil record of Metasequoia Miki is extensive and demonstrates that the genus was widely distributed throughout North America and Eurasia from the early Late Cretaceous to the Plio-Pleistocene. Given the reality of increasing human pressure and the inevitability of global change, efforts to conserve this ancient genus are underway. This book presents a definitive overview of fossil and living Metasequoia and was written by sixteen of the world’s experts on this important genus. The book reviews what is known about the biology, ecology and physiology of fossil and living Metasequoia, current research directions and problems that remain unresolved. It is the most up-to-date and comprehensive reference source for the genus and the authors have sought to incorporate obscure, hard-to-get and non-English reference sources. This book is a distillation of the collective efforts and results of the world’s Metasequoia specialists and enthusiasts. Today the genus is limited to one species with approximately 5,000 mature individuals growing in the Xiahoe Valley in southeastern China. The plant fossil record provides evidence that the genus Metasequoia was widely distributed and experienced a wide range of climatic and environmental conditions throughout the Northern Hemisphere from the early Late Cretaceous to the Plio-Pleistocene.
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