glyptostroboides ) (1–3, 5–8) and modern M. Leafy shoots, leaves and seed cones of fossil Metasequoia sp. SU Tao, principal investigator of the study. The intensification of the Asian monsoon in Yunnan during the Neogene most likely prevented necessary adaptations of the plants to increasing winter and spring aridity," said Prof. "We regard that the disappearance of Metasequoia from Southwest China might be related to the evolutionary stasis of Metasequoi. It was present in the Arctic cool temperate zone during the Eocene, in temperate zones, e.g., in Northeast China during the Paleogene as well as in nearly subtropical areas in Southwest China during the Neogene. The researchers also found that the genus has remained morphologically static at least since the early Neogene. The tree genus Metasequoia was initially only known in fossil records until a recent relic occurrence of this living fossil was found in China in 1941. glyptostroboides, the researchers identified their fossil materials as Metasequoia sp. Judging by the great morphological similarity between the fossils and extant M. It was initially described from fossil remains, only later found to be living in central China (H.-L. The Sanzhangtian fossils differ from other fossil-species of Metasequoia in seed cone phyllotaxis, which is exclusively decussate in the Sanzhangtian cones but mixed decussate–helical in the others. 21.105 ), the dawn redwood, is a member of this subfamily and is often described as a living fossil. The fossil record has been published in Review of Palaeobotany and Palynology.Ĭharacters of leafy shoots, including the cuticle micromorphology of the leaves and gross-morphology of seed cones, unambiguously refer the fossils from Sanzhangtian to the genus Metasequoia. It's the first Metasequoia fossil record in Southwest China and the southernmost fossil record of the genus around the world. Researchers from Xishuangbanna Tropical Botanical Garden (XTBG) have recently discovered numerous well-preserved leafy shoots and seed cones of Metasequoia from the middle Miocene deposits in Sanzhangtian, Zhenyuan County, Yunnan. ![]() ![]() The Arboretum provides the basis for research and education by Harvard faculty and students, Arboretum scholars, and visiting scientists from around the world.Although native to China, reliable Metasequoia megafossil records from only nine localities ranging from the Late Cretaceous to the middle Miocene have been reported in this country to date, most of them were reported from the northern part of China. ![]() The living collection is supported by comprehensive curatorial documentation, herbaria containing more than 1.3 million specimens, extensive library and archival holdings, and a 43,000-square-foot state-of-the-art research center. Occupying 281 acres, the Arboretum’s living collection of trees, shrubs, and woody vines is recognized as one of the most comprehensive and best documented of its kind in the world. The Arnold Arboretum of Harvard University discovers and disseminates knowledge of the plant kingdom to foster greater understanding, appreciation, and stewardship of Earth’s botanical diversity and its essential value to humankind.Įstablished in 1872 and planned and designed in collaboration with Frederick Law Olmsted, the Arnold Arboretum is a National Historic Landmark and one of the best preserved of Olmsted’s landscapes.
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