This has been found out by training bees to come for syrup to various parts of a spectrum or artificial rainbow thrown by a prism on a table in a dark room.

• 这一点是通过试验发现的：在暗室里的桌子上放一个粘着糖浆的三棱镜，三棱镜投射出光谱或人造彩虹，蜜蜂就会飞向光谱的各个部分来吃糖浆。