North Coast Diaries

Thayer's ain't so, Joe

You can always tell when there's a lull in the birding opportunities. Topics shift from what's happening now to venting about old news. Why should I be any exception?

Actually, I'm not so much venting as I am commenting on venting by others. And today's topic is the Iceland/Kumlien's/Thayer's complex and surrounding controversies. This may take some time.

When I first started birding, Thayer's was considered a subspecies of Herring Gull. Kumlien's was (and still is according to the AOU) considered a subspecies of Iceland Gull. Thayer's was elevated to a full species by the AOU in 1973 based on a couple of studies, one by Macpherson which showed reproductive isolation from Herring Gull and one by Smith that demonstrated reproductive isolation from Iceland Gull. Smith's work garnered considerable attention (including a popular treatment in Scientific American. It included experiments involving the painting of orbital rings on gulls and the dying of primaries. These experiments not only showed that Thayer's and Kumlien's practiced positive assortment, but also provided a mechanism for isolation.

Other researchers seriously began calling Smith's work into question in the 1980's. The challenges range from flawed methodologies and interpretations to outright fraud. Several researchers have attempted to repeat his experiments without success. Other studies have concluded that at the very least Kumlien's is a hybrid between Thayer's and Iceland Gulls rather than a discrete subspecies and many in the ornithological community have lumped Thayer's and Iceland into a single, highly variable species showing a stong clinal tendency east to west.

Ron Pittaway has posted a complete history of Thayer's Gull's checkered taxonomic history at Taxonomic History of Thayer's Gull that includes plenty of additional references.

Most of this information has been bouncing around in the literature for nearly 15 years.
What, if anything, is wrong with Smith's research?
Could he have really faked all the data for his Phd thesis?
Why hasn't the AOU gone lumping?
Could there be something less rational lurking in between the scientific arguements?

These are questions worth exploring.