The
Kradai or
Kra-Dai languages, also known as
Daic,
Kadai, or
Tai-Kadai, are a
language family of highly
tonal languages found in southern
China and
Southeast Asia. The diversity of the Kradai languages in southeastern China, especially on
Hainan, suggests that this is close to their
homeland. The
Tai branch moved south into
Southeast Asia only in historic times, founding the nations that later became
Thailand and
Laos in what had been
Austroasiatic territory.
External relationships
The Kradai languages were formerly considered to be part of the
Sino-Tibetan family, but outside of China they are now classified as an independent family. They contain large numbers of cognates with Sino-Tibetan languages. However, these are seldom found in all branches of the family, and do not include basic vocabulary, indicating that they are old loan words (Ostapirat 2005).
In China, they are called
Zhuang-Dong languages and are generally considered Sino-Tibetan along with the
Miao-Yao languages. It is still a matter of discussion among Chinese scholars whether
Kra languages such as
Gelao,
Qabiao, and
Lachi can be included in Zhuang-Dong, since they lack the Sino-Tibetan cognates that are used to include other Zhuang-Dong languages in Sino-Tibetan.
Several Western scholars believe that Kradai is related to or a branch of the
Austronesian language family, in a family called
Austro-Tai. There is a substantial but limited number of cognates in the core vocabulary. There is yet no agreement as to whether they are a sister group to Austronesian languages which remained on the mainland, a backmigration from Taiwan to the mainland, or a later migration from the Philippines to Hainan during the Austronesian expansion.
Internal classification
Kradai consists of five well established branches, Hlai, Kra, Kam-Sui, Tai, and the Ong Be (Bê) language:
- Ong Be (Hainan; Lin'gao in Chinese)
Based on the large number of vocabulary they share, the Kam-Sui, Be, and Tai branches are often classified together. (See
Kam-Tai.) However, this is
negative evidence, possibly due to lexical replacement in the other branches, and morphological similarities suggest instead that Kra and Kam-Sui be grouped together as Northern Kradai on the one hand, and Hlai with Tai as Southern Kradai on the other (Ostapirat 2006).
The position of Ong Be in this proposal is undetermined.
Origin and migrations
The study of over 100 East Asian populations including 30
Kradai-speaking peoples had reached the following conclusions. First, the Kradai-speaking populations show a great deal of genetic similarity although admixture with local populations did occur after its expansion.
Secondly, a significant proportion of southern Chinese populations carry a signature of Kradai-speaking populations.
Thirdly,
Taiwanese Aborigines are more similar to Kradai-speaking populations than they are to the other
Austronesian populations, that is, the
Malayo-Polynesians.
Fourthly, the clustering of subfamilies of Kradai-speaking populations correlates well with that based on their genetic similarity indicating limited gene flow between them after their separation.
Kradai-speaking populations originated in the southern part of East Asia and then migrated northwards and eastwards with Kam-Sui probably being the oldest.
