[Taxacom] DNA only descriptions

[Jason Mate]

 Apologies for not replying sooner Robin, alas I had to leave for a few days.

> Your discussion is good.  The siginificance of it is that some morphological 
> taxonomists are used to sitting in a chair and looking at dried or wet 
> (alcohol) specimens. Somehow they pickup/perceive a species problem that has 
> 2 or more cryptic species.  They know they will HAVE TO do some field work,
> perhaps even some extended field work.
> 
> This might actually be a good thing if the taxonomist states for the 
> specimens before him, "2 or more cryptic species", and then leaves the work 
> for a
> graduate student, and then goes off to do other morphological taxonomic 
> problems.

Yes, non-morphological studies are bringing to light an increasing number of cases of cryptic species. The key is not jumping the gun but simply to draw attention to these cases, mainly as a warning to end-users that a particular taxon may in fact be a complex. How much more data or of what sort is of course the problem and the source of the disagreement in this group! 


 
> Cryptic species can come in several main forms and includes: seasonal; 
> allopatric (which includes geographic and altitudinal); behavioral; and 
> chemical (pheromones).  A competent morphological taxonomist can explot the 
> allopatric aspects (e.g., separate all those collected at 1500 m alt from 
> those collected above 3500 m alt; those in different valleys from one 
> another; those on nearby but separate hills or mountains; etc.).  The 
> taxonomist can also start checking
> to see if there are seasonal "clumpings" (some in May and early June, none 
> in July, some in August).  What it means is the morphological taxonomist is 
> using non-morphological features to assist in a taxonomic problem.

Yes, but much of this data is severely lacking other than for birds, butterflies and popular mammals. Hopefully by raising warning flags ecologists, field biologists, etc will generate this data and feed it back, hopefully with additional specimens, so the species boundaries can be better reassesed. In spite of the frequent moans and whines the role that is truly endangered is that of the field biologist. Phylogenies are great for our pattern-hungry minds to help us understand (i.e. reduce) the complexity of life but they are a pretty useless exercise if there is no other data than dead specimens and their genetic code.

> I know the seasonal and allopatric systems work, as I have used them to 
> solve taxonomic problems.  Behavioral might take a lot of field time, and
> chemical - well I just don't have the facilities for it, and don't know 
> anyone who has.  But the options are there.  Who knows?  It might be easier 
> to
> do these than try to tie in with a molecular person.
> Of course I am thinking that the taxonomist has more than 2 or 3 specimens, 
> as issues of cryptic species usually come in when there are many specimens
> to consider.

Well through experience with your group of choice you have figured the best way to deal with the problem. But this angle has come from field experience. I think in the end it comes down to our interpretation of what species are, and that is very much an acquired "feel".  Personally I used to fall under the typological concept at first, gradually I gravitated towards the cladistic until I realised that in its current incarnation I results in speciation paradoxes (anybody care to talk about polar and brown bears?) :) Increasingly I find Mayr´s angle to be the most practical for me.

Best

Jason