Male birds are colorful for courtship displays, females are dull for camouflage. But, is written in a website somewhere that sometimes, when females birds are sterile, they grow male plumage due to male's feathers being a dormant gene (or something like that, sorry, I'm no professional). Is true? Can it happen? If so, how came? (and I lost the website's link, so I can't post it here, sorry again)
I don't have a link to a reference, but I was told by an ornithologist last week that in the UK, female blackbirds (usually brown plumage and brown beak) can sometimes change to more resemble males later in their lives (black plumage and orange beak).
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