The human nose is very good at smelling this particular chemical.
your nose can smell geosmin better than a shark can smell blood in the water. Put this into perspective, a shark can smell a single drop of blood from a mile away
The human eye can see more shades of green than any other colour. It’s left over from us being apes and being able to spot a predator amongst vegetation,.
@HeidiA the funny thing is that grass is not green. it reflects the wave spectrum of green light. green is a color that is missing from the properties of grass.
