40,000 years ago when Taiwan and the Mainland were part of the same land mass, the climate changed and the connecting glacier melted away leaving Taiwan and the Formosan Rock Monkey to develop separately and differently from the Mainland.
台灣原與大陸相連，後來冰河溶化，台灣成為孤島，遷徙而來的獼猴無法返回，只有適應環境，經過四萬多年的演化，成為今天獨特的品種。