Effect of air pollution on birds plumage made evident

[jack]

I think many know of the phenomena of the changing colors of moths in Industrial England in the 19th century, as their colors turned darker and browner so as not to be easily seen on the sides of sooty buildings and other landing platforms. It appears, now, that birds also experienced a change in color as their plug color also became a darker, sootier color as air pollution changed the colors of objects around them.
https://www.nytimes.com/2017/10/10/s...e=sectionfront