Editing Tea (section)

===Botanical origin===

[[File:Camellia sinensis - Köhler–s Medizinal-Pflanzen-025.jpg|thumb|Tea plant (''Camellia sinensis'') from ''[[Köhler's Medicinal Plants]]'', 1897]]

Tea plants are native to East Asia and the probable center of origin of tea is near the source of the [[Irrawaddy River]] from where it spread out fan-wise into southeast China, Indo-China and [[Assam]]. Thus, the natural home of the tea plant is considered to be within the comparatively small fan-shaped area between [[Nagaland]], [[Manipur]] and [[Mizoram]] along the [[Myanmar|Burma]] frontier in the west, through [[China]] as far as the [[Zhejiang|Zhejiang Province]] in the east, and from this line generally south through the hills to Burma and [[Thailand]] to [[Vietnam]]. The west–east axis indicated above is about 2,400&nbsp;km long extending from longitude 95°-120°E. The north–south axis covers about 1,920&nbsp;km, starting from the northern part of Burma, latitude 29°N passing through [[Yunnan]], [[Tonkin|Tongkin]], Thailand, [[Laos]] and on to Annan, reaching latitude 11°N.<ref>{{Cite web |last=Saikia |first=Gautam Kumar |date=19 September 2021 |title=Origin And Distribution Of The Tea Plant |url=https://teaorb.com/en-us/blog/origin-of-tea |website=teaorb.com}}</ref>

Chinese (small-leaf) type tea (''C. sinensis'' var. ''sinensis'') may have originated in southern China possibly with hybridization of unknown wild tea relatives. However, since there are no known wild populations of this tea, its origin is speculative.<ref name="Meegahakumbura 1"/><ref name="Meegahakumbura 2"/>

Given their genetic differences forming distinct [[clade]]s, Chinese Assam-type tea (''C. sinensis'' var. ''assamica'') may have two different parentages – one being found in southern [[Yunnan]] ([[Xishuangbanna]], [[Pu'er City]]) and the other in western Yunnan ([[Lincang]], [[Baoshan, Yunnan|Baoshan]]). Many types of Southern Yunnan Assam tea have been hybridized with the closely related species ''[[Camellia taliensis]]''. Unlike Southern Yunnan Assam tea, Western Yunnan Assam tea shares many genetic similarities with Indian Assam-type tea (also ''C. sinensis'' var. ''assamica''). Thus, Western Yunnan Assam tea and Indian Assam tea both may have originated from the same parent plant in the area where southwestern China, Indo-Burma, and Tibet meet. However, as the Indian Assam tea shares no [[haplotype]]s with Western Yunnan Assam tea, Indian Assam tea is likely to have originated from an independent domestication. Some Indian Assam tea appears to have hybridized with the species ''[[Camellia pubicosta]]''.<ref name="Meegahakumbura 1">{{cite journal |last1=Meegahakumbura |first1=MK |last2=Wambulwa |first2=MC |last3=Thapa |first3=KK |display-authors=etal |year=2016 |title=Indications for three independent domestication events for the tea plant (''Camellia sinensis'' (L.) O. Kuntze) and new insights into the origin of tea germplasm in China and India revealed by nuclear microsatellites |journal=PLOS ONE |volume=11 |issue=5 |page=e0155369 |pmid=27218820 |pmc=4878758 |doi=10.1371/journal.pone.0155369 |bibcode=2016PLoSO..1155369M|doi-access=free }}</ref><ref name="Meegahakumbura 2">{{cite journal |vauthors=Meegahakumbura MK, Wambulwa MC, Li MM, Thapa KK, Sun YS, Möller M, Xu JC, Yang JB, Liu J, Liu BY, Li DZ, Gao LM |display-authors=3 |date=2018 |title=Domestication origin and breeding history of the tea plant (Camellia sinensis) in China and India based on nuclear microsatellites and cpDNA sequence data |journal=Frontiers in Plant Science |volume=8 |page=2270 |pmid=29422908 |pmc=5788969 |doi= 10.3389/fpls.2017.02270|doi-access=free }}</ref>

Assuming a generation of 12 years, Chinese small-leaf tea is estimated to have diverged from Assam tea around 22,000 years ago, while Chinese Assam tea and Indian Assam tea diverged 2,800 years ago. The divergence of Chinese small-leaf tea and Assam tea would correspond to the last [[Ice age|glacial maximum]].<ref name="Meegahakumbura 1"/><ref name="Meegahakumbura 2"/>