Why are Leaves not Black? Light must be absorbed for nutrients to be created by Photosynthesis. So why reflect the green and waste the whole middle part of the spectrum? According to Moore, et al., this is a long story; in fact ancient history!

It looks like chlorophyll takes the part of the spectrum that bacteriorhodopsin doesn't take. Bacteriorhodopsin is a purple pigment that resembles the light-sensitive pigment in our eyes. Current understanding is that the earliest photosynthetic organisms were aquatic bacteria, some of which are still around today. One of these, halobacterium halobium, grows in extremely salty water. It makes use of the bacteriorhodopsin pigment. The chlorophyll system developed to use the available light, as if it developed in strata below the purple bacteria and had to use what it could get. But what about the development of land plants? Why did they stay green? The thoughts are that they had plenty of light and were not pressured to develop more efficient light gathering. That is, the light was not the limiting resource in photosynthesis for plants. That being said, there is some extension toward the middle of the spectrum with the beta carotene and other pigments. Photosynthetic Efficiency Energy cycle in living things