Re: Hierarchal vs Non-Hierarchal Interfaces to Biological Taxonomy

Bob Badour wrote:

> Which common bird is it that has three cohorts A, B and C where A and B
> can interbreed, B and C can interbreed but A and C cannot? Is it the robin?

There's lots of species like that -- it's called a ring species. I think it's the salamander where every subspecies but two can interbreed.

An interesting question is when you have subspecies A, B & C, where A & C cannot interbreed, and B goes extinct, do you now have two distinct species?  

Larry Coon
University of California Received on Fri Dec 22 2006 - 21:49:28 CET