"The lush green planet that we call home may have actually looked purple in its earliest days, according to the "Purple Earth hypothesis."
No, this doesn't mean there were purple trees or purple grass or purple animals. It would have been before any multicellular organisms even evolved, when single-cell microorganisms dominated the planet and possibly created a purple hue that could be seen from space.
These purple organisms may have reigned supreme and existed in varying concentrations across the planet, said Shiladitya DasSarma, a microbiologist and professor at the University of Maryland. DasSarma has studied one of these microorganisms and created the Purple Earth hypothesis."
"and possibly created a purple hue that could be seen from space."
In other words, our very sky could have been purple according to these studies.
You would think somebody would notice something like that...
The old creatures of the earth (hominids, dinosaurs, lemurs, tarsiers, owls etc.) all had the same huge dark world/purple Dawn adapted eyes. Humans and Dolphins with the smallest relative eye sizes of advanced creatures, could not reasonably be assumed to have arisen in this deep purple/darkish environment which was the original environment of this planet. The bright northern part of the ancient system (sun, Jupiter, Mercury) contained at least one place (Ganymede) which would have been an ideal home world for humans under those kinds of circumstances.
The Neanderthal has always been thought to be a primitive human rather than an advanced ape, mainly because of the size of his brain. But, funny thing, the Neanderthal brain was dominated by the area of the brain involved with vision and that in combination with the huge eyes basically indicates that the Neanderthal brain was largely the neurological equivalent of the circuitry for a military night vision system. The Neanderthal was basically an advanced bipedal ape and not a primitive human.