When Earth Was Purple

What if I told you… Earth almost looked completely different. Billions of years ago,

before plants existed, the dominant life on Earth wasn’t green. It was purple.

Early microbes used a molecule called retinal instead of chlorophyll to capture sunlight.

And retinal reflects purple light. Which means oceans, coastlines, even large parts

of the planet… may have had a purple tint. Then plants evolved chlorophyll.

Chlorophyll was better at using sunlight, so it spread everywhere. Green took over.

Purple life faded into the background. But here’s the creepy part— Some scientists

think this matters when searching for aliens. Because if another planet is purple