Descendants of the Chinese people, why is the Emperor Yan in the front and the Yellow Emperor in the back?

Hello: Yandi Shennong has been handed down for three generations, and Emperor Xuanyuan was originally a vassal of Shennong. Later, due to the corruption of the third generation Shennong, it was overthrown by the Yellow Emperor and the Yanhuang tribe merged. Therefore, Emperor Yan comes first and Yellow Emperor comes last. Another way of saying it is that in the legend handed down, Emperor Yan Shennong tasted a hundred herbs for the people, and finally found the seeds that could be cultivated and taught the people to cultivate. In everyone's eyes, this achievement is higher than that of the Yellow Emperor.