Art asked:
>
>As many of you know, I have pushed DNA studies for some time to
>establish relationships between mollusks. I do that as if I really
>understood what I was talking about. The OJ case showed that there
>are DNA differences between creatures of the same species. What I
>want to know is if DNA studies can also tell which species are
>closely related, and if species separated by geography but which look
>alike are truly the same or different species. It occurs to me that
>in our present technological age, we should be using something other
>than outside looks to establish relationships. Are any museums
>equiped to do these examinations? What's it cost? Should we be
>putting new names on things when there is still a chance the "thing"
>already has a name?
>                 Your humble Question Man
 
Some museums and universities are starting to do DNA studies.  However,
they are expensive.  Two particular cautions should be noted.  First, you
need to determine how much variation is found within a species, as some
taxa are more variable than others.  For example, the ITS sequence in some
plants varies more between copies within one plant than it does between
species, but it seems useful for recognizing species of oysters.  Secondly,
unless a DNA sequence can be obtained from your specimen, it may not be
possible to be sure that your new name really applies to the DNA-supported
species.  Usually, people have been able to go back and figure out
distinctive morphological features that distinguish things with different
DNA, but it may be difficult.
 
David Campbell
 
"Old Seashells"
 
Department of Geology
CB 3315 Mitchell Hall
University of North Carolina at Chapel Hill
Chapel Hill NC 27599-3315
USA
 
919-962-0685
FAX 919-966-4519
 
"He had discovered an unknown bivalve, forming a new genus"-E. A. Poe, The
Gold Bug