Song Sparrow

If you take a quick look at the song sparrow range map (the one that shows all of North America, not just the supposed North America that only includes the US and Canada,) you will notice something interesting.  There is a contiguous population across the bird-guide version of North America and then a little island of sparrows alone down in Mexico.   Geographic isolation usually means genetic isolation, and so it happens to be.  Sometimes it’s nice to have different parts of my life connecting, and it was nice to find that the sparrows I was pondering down in Veracruz happen to be the same birds my professor, Bob Zink, from the U of M published about many years before. http://www.jstor.org/pss/2410178