Why does the human eye see more shades of green than any other?

On a bell curve of colors distinguished by the human eye, greens are right in the middle. This is an adaptation based on humans interacting in the natural world, where green are predominant. Greens are perceived more readily than any other color because of the combined color perception of rods and cones -- read below:

"A range of wavelengths of light stimulates each of these receptor types to varying degrees. Yellowish-green light, for example, stimulates both L and M cones equally strongly, but only stimulates S-cones weakly. Red light, on the other hand, stimulates L cones much more than M cones, and S cones hardly at all; blue-green light stimulates M cones more than L cones, and S cones a bit more strongly, and is also the peak stimulant for rod cells; and blue light stimulates S cones more strongly than red or green light, but L and M cones more weakly. The brain combines the information from each type of receptor to give rise to different perceptions of different wavelengths of light."
https://en.wikipedia.org/wiki/Color_vision#Theories_of_color_vision