Tujia dog is a small hairless beast that only lives in the southern United States. Before humans settled in the southern United States, Tujia's natural enemies were not strong, so Tujia thrived in the southern United States. When humans began to hunt them, Tujia dog became extinct. 
Since the first humans settled in the southern United States, Tujia dogs have still existed in some parts of the southern United States for about 300 years
 it must be people's minefields that led to its extinction.