"Missing" branches

Proto-Hmong-Mien, Proto-Kra-Dai, Proto-Kra, and Jiamao contain lexical strata derived from currently extinct Eastern Sino-Tibetan branches. This points to a wider former extant of diverse Sino-Tibetan branches in southern China (Guangxi, Guangdong, and Hunan) prior to the expansion of Sinitic. The expansions of Kra-Dai, Hmong-Mien, and Sinitic since the Bronze Age have absorbed this former Sino-Tibetan diversity.

From the Proto-Sino-Tibetan homeland in the Upper Yangtze, speakers of these branches would have migrated downstream into the Pearl River drainage basin as well as into modern-day Hunan.

These Sino-Tibetan branches in southern China share similarities with Lolo-Burmese, Qiangic, rGyalrongic, and the various Arunachal languages, pointing to their being part of an ancient "Eastern Sino-Tibetan" linkage of diverse branches that would have covered much of southwestern China.