Re: Hierarchal vs Non-Hierarchal Interfaces to Biological Taxonomy
Date: Fri, 15 Dec 2006 16:06:15 +0000
Message-ID: <tih5o25gadj8gk7iu5kl1chcsificvcvfp_at_4ax.com>
Bob Badour <bbadour_at_pei.sympatico.ca> wrote:
> > I'd start looking at the Tree of Life Project:
> > http://tolweb.org/tree/
> 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?
I used to study genetics, and there are several types of animal that can do this - IIRC from my studies, there is a (super-)species of American prairie dog that has three sub-species - Rocky, Plain and Appallachian.
R and P can breed, and P and A can breed, but R and A cannot.
There is a point at which the genetic distance between two creatures leads not to hybrid vigour but rather to infertility and/or sterility of the resultant offspring (horse + donkey = mule).
Paul...
-- plinehan __at__ yahoo __dot__ __com__ XP Pro, SP 2, Oracle, 9.2.0.1.0 (Enterprise Ed.) Interbase 6.0.1.0; When asking database related questions, please give other posters some clues, like operating system, version of db being used and DDL. The exact text and/or number of error messages is useful (!= "it didn't work!"). Thanks. Furthermore, as a courtesy to those who spend time analysing and attempting to help, please do not top post.Received on Fri Dec 15 2006 - 17:06:15 CET