Pink Forest, Ireland

It's not really pink

This photo reminds me of the 'purple earth' theory. Apparently, it is likely that earlier plants used retinal pigments rather than chlorophyll to absorb sunlight. Retinal pigments have a simpler molecular structure, and therefore probably evolved before chlorophyll. So, in all likelihood, Earth resembled something like this photo. Perhaps it is not as unnatural as we perceive it to be ;)