020720 Claremore Edition, Birding Today

https://www.claremoreprogress.com/news/lifestyles/birding-today-migration-can-help-keep-species-intact/article_580cb080-4999-11ea-b2ed-f3439200f312.html

042918 Muskogee Phoenix Edition, Birding Today

http://www.muskogeephoenix.com/news/birding-today-keep-eye-out-for-examples-of-dimorphism-in/article_2138c692-4b54-11e8-adcc-7ff95bf9c16e.html

Natural Selection and What "Black" vs. "Really Black" Feathers Means

https://gizmodo.com/these-birds-evolved-feathers-so-dark-they-re-like-a-b-1821906446

Did Natural Selection Destroy the Passenger Pigeon?

https://www.nytimes.com/2017/11/16/science/passenger-pigeons-extinction.html