This is from a northern flicker. Notice the orange-red shaft. Red-shafted northern flickers live in the western part of North America and yellow-shafted ones live in the eastern part. No other bird I know of displays yellow or orange color in its feathers’ shafts. Most bird’s feather shafts are whitish, some are black.
Taking a quick look at the research*, I learned that the color in these shafts (and other parts of the feathers) is made through metabolizing what the birds eat: food with carotenoids. This is the same food ingredient that many kinds of birds use to make colored feathers, reds, oranges, and yellows. The yellow shafted northern flickers metabolize their food in a slightly different way to make the yellow color than the red shafted flickers metabolize for the orange color.
I found speculation but little solid information that explains how birds use the yellow and orange-shafts; how it helps them live their lives.
People sometimes send me images of feathers they have found and want to know what bird it is from. This one was easy.
*Karen L. Wiebe and Gary R Bortolotti, Variation in Carotin-based color in Northern Flickers in a Hybrid Zone. Wilson Bull., 114(3), 2002, pp. 393–400