why is blue so uncommon in nature?

this photo made me wonder why the color blue is so difficult to find in nature. a quick google search turned up several explanations all explaining the same thing–that there is no blue pigment in nature, and all the blue we see is really manipulated light waves.

Most pigments that animals exhibit on their fur, skin or feathers due is related to the food they consume. Salmon is pink because of the pink shellfish they eat. Goldfinches get that yellow color from the yellow flowers they consume. But while pigments like red, brown, orange, and yellow come from the food animals eat, that’s not the case with blue. In fact, that blue you see is not really a pigment at all.

When blue does appear in nature, it’s related to other reasons than pigment. In many animals, that blue color is due to the structure of the molecules and the way they reflect light. For example, the blue morpho butterfly (which you might recognize as the butterfly emoji), gets its color from the fact that its wing scales are shaped in ridges that causes sunlight to bend in such a way that blue light, at just the right wavelength, makes it to our eye. If the scales were shaped differently or if something other than air was filling the gaps between them, the blue would vanish.

well, i thought that was pretty interesting. and then i stumbled on this little factoid too:

The ability of us humans to see the color blue is relatively recent in our evolution. No one could see the color blue until modern times. There are studies that show that certain tribes in Africa cannot distinguish blue from green but can see nuances in green that most of us cannot see.

all that from contemplating one fallen mallard feather.

mallard feather