White-throated Sparrow
White-throated Sparrows; Per the Internet: White-throated Sparrows can have white, tan, or grayish crown stripes. Throughout its extensive range the White-throated Sparrow shows no sub-specific variation. However, it exhibits plumage polymorphism (white-striped and tan-striped morphs) in both sexes, most obvious in the breeding season, associated with a difference in an autosome.
Though I've photographed both, today I was able to get one of each in a photo together. Took a while to get a photo where both birds had eye contact.