When I was a young boy growing up in Germany, a popular fairy tale featured “Schlaraffenland,” a place where rivers flowed with milk and honey, houses were made of cake, and roast chickens flew in the air with forks already stuck in them, waiting for you to grab them. This finch lives in something like that. He’s surrounded by his favorite food, seeds, and just has to reach up to have some. Or he could reach left, right, or down — they’re everywhere.
These finches bear the misleading label of House Finches even though they flourished in the wild long before some unscrupulous entrepreneurs put them in cages and sold them as house birds. They’re unusual among bird parents in that they’ll feed their babies only vegetarian food. Most birds, even if their normal diet is vegetarian, will switch to bugs when breeding so as to give their hatchlings protein.
The color of the males, the sources say, comes from carotenoids, and this chemical comes from the foods they eat. I did some digging to try to find out what kind of seeds likely to be in the finch diet were highest in carotenoids, but came up dry. The sources also don’t explain why carotenoids turn male finch feathers red but don’t have the same effect in females, even though presumably they eat the same diet. In Flamingoes, by contrast, a carotene-rich diet produces the same coloration in both genders. Readers who know more about this subject are warmly invited to comment below.