Four colly birds

At a caroling party tonight, someone asked me, what is a calling bird? The answer always seemed obvious enough-- namely, any old bird singing. Wrong!

Wikipedia tells us that "...the line commonly sung today as 'four calling birds' is believed to have originally been written in the 18th century as 'four colly birds,' an archaism meaning 'black as coal' that was a popular English nickname for the Common Blackbird."

The common blackbird is a European thrush not closely related to our New World blackbirds, but in the same genus as our American robin, which in turn is not related to the bird Europeans call a robin. Got it? The colly bird is the blackbird Paul sings about in the beautiful Beatles song. Thrushes are generally wonderful singers. New World blackbirds... not so much.