Why Plants are Green
The sun emits its highest amount of energy in the green spectrum. It seems counter-intuitive that plants would reject the most abundant light source, but it seems they evolved this way for 2 reasons:
Evolutionary accident : Ancestors of plant photosynthesis evolved in an environment where purple microbes that absorbed green light were dominant - they evolved to use the leftovers
Energy stability given solar input noise : If purple competitors weren’t around, you might assume plants would evolve to be black to absorb all available light energy. However, absorbing 100% of the sun’s energy provides too much thermal and electronic stress. A black plant would easily overheat, damage its DNA, and suffer from extreme energy volatility.