A NASA study once revealed Earth had purple oceans
Earth's oceans were once covered in purple and green sulphur bacteria that prevented life forms, such as fish and mammals, from thriving as confirmed by a NASA research. The 2005 study analysed fossilised remains of photosynthetic pigments preserved in 1.6 billion-year-old rocks in Australia. It stated that purple bacteria appeared close to the surface as they required high-intensity sunlight.