It’s been about a year since I wrote here about how swiftly, how dramatically, our conception of the world of birds is changing these days.
I was at the last annual AOU meeting then, and at the time, much of the buzz still centered around a certain woodpecker in Florida. But for my money, the most exhilarating moment of the meeting was delivered by scientists who were using mtDNA and nuclear data to shed light upon a group of birds known as nine-primaried oscines -- tanagers, cardinals and grosbeaks, New World sparrows, New World blackbirds, and wood-warblers.
The methods the scientists described sounded highly technical and their discussions were loaded with jargon, but their conclusions were thrilling.
Among them: that our Scarlet, Western, Hepatic, and Summer Tanagers aren't really tanagers; that five genera currently assigned to the New World sparrows are probably better placed elsewhere in the songbird tree; that two genera now placed among the tanagers appear to belong within the sparrows; and that Olive Warbler and the chats don’t properly belong with the wood-warblers.
I remember thinking then how lucky I was to be present at just the moment when an established worldview was swept away and we were asked to look at the avian tree of life, or a part of it, in a new way.
I have that feeling again today.
Because today, scientists who have spent the last five years examining DNA not just from the nine-primaried oscines but from all major living groups of birds are publishing their findings, and they are every bit as thrilling as those announced last year. Indeed, they promise not only to send the writers of biology textbooks and field guides back to their drawing boards but to shake our understanding of evolution.