Day 18.018: Chipping, hairy, downy

Here's a chipping sparrow recently visiting our feeder:

I'd been meaning to look up the origin of the names "hairy woodpecker" and "downy woodpecker" for some time. I assumed that one was named for its similarity with but different size from the other. The story I found was quite surprising. Indeed, it seems that hairy was named for its similarity to the previously named downy, but later it was discovered that they are not closely related - their very close resemblance being attributed to convergent evolution.