The color of life in the universe

Part of the reason plants are green is that at the beginning of their history, they probably had to compete with other organisms.

These were able to make use of sunlight thanks to a pigment called retinol.

Organisms equipped with retinol were the first to carry out photosynthesis, and since the molecule absorbs green light (which is also the most abundant light that reaches Earth) the most efficiently, they reflected the blue and red components of the solar spectrum and thus had a violet color.