The identity of the Neolithic pre-Austronesian cultures in China is contentious. Tracing Austronesian prehistory in mainland China and Taiwan has been difficult due to the southward expansion of the Han dynasty (2nd century BCE), and the recent Qing dynasty annexation of Taiwan (1683 CE). Today, the only Austronesian language in southern China is Tsat language in Hainan. The politicization of archaeology is also problematic, particularly erroneous reconstructions among some Chinese archaeologists of non-Sinitic sites as Han. Some authors, favoring the "Out of Sundaland" model like William Meacham, reject the southern Chinese mainland origin of pre-Austronesians entirely.