With this question, I checked the information and found that behind the elephant's northward migration, there was a secret pusher of dynasty change-temperature change.
In fact, in ancient China, elephants were distributed throughout the Central Plains, not just in a few areas of Yunnan. There is a lot of evidence. Jade statues unearthed from Yin Ruins in Anyang indicate that there were statues in Henan in Shang and Zhou Dynasties. Even the abbreviation of Henan-Yu is spear+elephant.
At the end of the Eastern Han Dynasty, Cao Chong called elephants, which happened in Hebei, indicating that Hebei at that time was as common as cattle now.
Later, the elephant disappeared. People only knew that there was an elephant in the legend, so the word "imagination" came into being. What made the elephant never come back? The mysterious force behind this is the temperature change in the earth's great cycle.
As can be seen from the figure, the annual average temperature in China has been lower than the baseline for more than 1000 years since the Song Dynasty. On the whole, the historical temperature curve shows a downward trend. When the temperature dropped, the elephant went to the south.
Now the elephants are migrating to the north, which shows that China is in a small cycle of rising temperature. Rising temperature, increasing rainfall and increasing grain crop output are conducive to population growth.
The prosperous times in China's history-Shang and Zhou Dynasties, Han and Tang Dynasties-all appeared in the high temperature era. Now that history is heating up again, I hope that the Millennium will come to China again.