Brian Sharp wrote:

> 20-3 years ago, we were all informed that according to expert
> opinion the latest research had proved that these were single species
> with interbreeding populations, etc. Now expert opinion tells us they
> are good, separate species. What happened?

I don't know the specifics of these cases, but if birders are going to
base their lists on scientific opinion, those lists are going to keep
changing. It's the nature of science. When I was in high school, humans
had 48 chromosomes. (Showing my age here.) That was the truth. The
textbooks said so. Then better techniques were developed and now humans
have 46 chromosomes. This is the truth. All the textbooks say so. Next
week the number could be 44 or 50. I don't really believe that, but the
point is that people keep looking with fresh eyes and acquiring new
knowledge. Also, the conception of how best to delineate species keeps
changing, as tweets know from several heated debates over the last few years.
I think this is one reason it's so silly to just keep lists with the
aim of getting more and more, rather than being interested in the birds
themselves and the pleasure they can bring.

Burt Guttman guttmanb at elwha.evergreen.edu
The Evergreen State College Voice: 360-866-6000, x. 6755
Olympia, WA 98505 FAX: 360-866-6794

"Have you ever noticed that you never see Rush Limbaugh and Barney the
Dinosaur together? Think about it!"