rather than to common inheritance. Chamberlain (1998) argues that the Red River Delta region was originally Tai-speaking and became Vietnamese-speaking only between the seventh and ninth centuries AD as a result of emigration from the south, i.e., modern Central Vietnam, where the highly distinctive and conservative North-Central Vietnamese dialects are spoken today. Therefore, the region of origin of Vietnamese (and the earlier Viet–Muong) was well south of the Red River. On the other hand, Ferlus (2009) showed that the inventions of pestle, oar and a pan to cook sticky rice, which is the main characteristic of the Đông Sơn culture, correspond to the creation of new lexicons for these inventions in Northern Vietic (Việt–Mường) and Central Vietic (Cuoi-Toum). The new vocabularies of these inventions were proven to be derivatives from original verbs rather than borrowed lexical items. The current distribution of Northern Vietic also corresponds to the area of Dong Son culture. Thus, Ferlus concludes that the Northern Vietic (Viet-Muong) is the direct heirs of the Dongsonian, who have resided in Southern part of Red river delta and North Central Vietnam since the 1st millennium BC. Furthermore, John Phan (2013, 2016) argues that “Annamese Middle Chinese” was spoken in the Red River Valley and was then later absorbed into the coexisting Proto-Viet-Muong, one of whose divergent dialects evolved into the Vietnamese language. Annamese Middle Chinese belonged to a Middle Chinese dialect continuum in southwestern China that eventually "diversified into" Waxiang Chinese, the Jiudu patois 九都土話 of Hezhou, Southern Pinghua, and various Xiang Chinese dialects (e.g., Xiangxiang 湘鄉, Luxi 瀘溪, Qidong 祁東, and Quanzhou 全州). Phan (2013) lists three major types of Sino-Vietnamese borrowings, which were borrowed during different eras: Early Sino-Vietnamese (Han dynasty (ca. 1st century CE) and Jin dynasty (ca. 4th century CE) layers) Late Sino-Vietnamese (Tang dynasty) Recent Sino-Vietnamese (Ming dynasty and post-Ming dynasty) Distribution Vietic speakers reside in and around the Nakai–Nam Theun Conservation Area of Laos and north-central Vietnam (Chamberlain 1998). Many of these speakers are referred to as Mường, Nhà Làng, and Nguồn. Chamberlain (1998) lists current locations in Laos for the following Vietic peoples. An overview based on first-hand fieldwork has been proposed by Michel Ferlus. Nguồn: Ban Pak Phanang, Boualapha District, Khammouane; others in Vietnam Liha, Phong (Cham), and Toum: Khamkeut District; probably originally from the northern Nghe An / Khamkeut border area Ahoe: originally lived in Na Tane Subdistrict of Nakai District,