Sequoia sempervirens - Video Learning - WizScience.com

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""Sequoia sempervirens"" is the sole living species of the genus "Sequoia" in the cypress family Cupressaceae . Common names include "coast redwood", "coastal redwood" and "California redwood". It is an evergreen, long-lived, monoecious tree living 1,200–1,800 years or more. This species includes the tallest living trees on Earth, reaching up to 379 ft in height and up to 29.2 ft in diameter at breast height / dbh. These trees are also among the oldest living things on Earth. Before commercial logging and clearing began by the 1850s, this massive tree occurred naturally in an estimated 2100000 acre along much of coastal California and the southwestern corner of coastal Oregon within the United States. An estimated 95% or more of the original old-growth redwood trees have been cut down. The name "sequoia" sometimes refers to the subfamily Sequoioideae, which includes "S. sempervirens" along with "Sequoiadendron" and "Metasequoia" . On its own, the term "redwood" usually refers to the coast redwood, which is covered in this article, and not to the other two species. Scottish botanist David Don described the redwood as the evergreen taxodium in his colleague Aylmer Bourke Lambert's 1824 work "A description of the genus Pinus". Austrian botanist Stephan Endlicher erected the genus "Sequoia" in his 1847 work "Synopsis coniferarum", giving the redwood its current binomial name of "Sequoia sempervirens". The redwood is one of three living species, each in its own genus, in the subfamily Sequoioideae. Molecular studies have shown the three to be each other's closest relatives, generally with the redwood and giant sequoia as each other's closest relatives. However Yang and colleagues in 2010 queried the polyploid state of the redwood and speculate that it may have arisen as an ancient hybrid between ancestors of the giant sequoia and dawn redwood . Using two different single copy nuclear genes, LFY and NLY, to generate phylogenetic trees, they found that "Sequoia" was clustered with "Metasequoia" in the tree generated using the LFY gene, but with "Sequoiadendron "in the tree generated with the NLY gene. Further analysis strongly supported the hypothesis that "Sequoia" was the result of a hybridization event involving "Metasequoia" and "Sequoiadendron". Thus, Yang and colleagues hypothesize that the inconsistent relationships among "Metasequoia", "Sequoia," and "Sequoiadendron" could be a sign of reticulate evolution among the three genera. However, the long evolutionary history of the three genera make resolving the specifics of when and how "Sequoia" originated once and for all a difficult matter—especially since it in part depends on an incomplete fossil record. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Sequoia+sempervirens, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.