[Taxacom] North America, Central America + S.E. Asia sister taxa

[John Grehan]

Kip,

Thank you for the clarification. I guess I am puzzled about your
referring to it as a 'peculiar' distribution, at least with respect to a
taxon existing in South East Asia and the New World since these types
are patterns are commonplace and are spatially diagnostic as being
trans-Pacific.

Admittedly, many such groups may lack a rigorous phylogenetic analysis,
but on the other hand I suspect many do.

John Grehan

-----Original Message-----
From: Kipling (Kip) Will [mailto:kipwill at berkeley.edu] 
Sent: Tuesday, December 20, 2011 9:55 AM
To: John Grehan
Cc: TAXACOM
Subject: Re: [Taxacom] North America, Central America + S.E. Asia sister
taxa

John,

We have a group of carabid beetles that includes a very well supported 
clade with one lineage restricted to the area of roughly Myanmar to 
Vietnam and the other in North America (southern Canada) south to 
Central America (Panama). This strikes me as a peculiar distribution and

so the first step to understand its significance (if any) is to look for

similar patterns of phylogeny and distribution.

Sister groups, by definition, have some useful properties, e.g. have 
been shown to share a most recent common ancestor and are lineages of 
the same age. Therefore they provide us with comparable evolutionary 
entities.

I am specifically looking for sister groups since taxa s.l. may or may 
not have an associated phylogeny and so a family, for example, might (or

might not) just be a group of convenience. Even worse, it may be a 
paraphyletic construct that excludes some descendents leaving only those

that happen to be in the areas of interest. The distributional pattern 
based on a paraphyletic grade would be incomplete and therefore 
misleading. Of course if the taxon has been shown to be monophyletic, 
that is it contains all the decedents of a common ancestor, and its 
extant members are only from North America, Central America and S.E. 
Asia, even if the internal relationships have not been resolved, it is 
of interest to me.

Considering other patterns of phylogeny and distribution that involve 
these areas, more widely distributed taxa and extinct organisms may be 
necessary to develop the full picture.

best,
Kip



On 12/19/2011 5:56 PM, John Grehan wrote:
> Just 'sister groups' or what about the same taxon such as genus or
> family etc. What's the significance of sister groups you are looking
at?
>
> John Grehan
>
> -----Original Message-----
> From: taxacom-bounces at mailman.nhm.ku.edu
> [mailto:taxacom-bounces at mailman.nhm.ku.edu] On Behalf Of Kipling (Kip)
> Will
> Sent: Monday, December 19, 2011 4:59 PM
> To: TAXACOM
> Subject: [Taxacom] North America, Central America + S.E. Asia sister
> taxa
>
> Dear All,
> I am looking for examples of taxa with demonstrated sister groups in
> which one is endemic to all or part of South East Asia and the other
to
> all or part of North and/or Central America. Any citations or clues
> appreciated.
>
> best,
> Kip
>
>


-- 

Contact info:

Kipling W. Will
Associate Professor/Insect Systematist
Associate Director,Essig Museum of Entomology

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