[Taxacom] Biodiversity and conservation

[Ken Kinman]

Dear Bob and other Taxacomers:
      By biodiversity I was referring to a section of the tree of life.  The 
Family Craseonycteridae presumably once had a much higher number of species, 
and extinction has left us with only one extant species within a very small 
relictual geographic range.  By contrast, the two Families to which it is 
most closely related have a larger number of extant species.  Therefore the 
loss of the single extant species of Craseonycteridae would very roughly be 
equivalent (from a biodiversity standpoint) to the loss of all members of 
one of those other two families (or at the very least the loss of a subset 
of one of those families should one of them turn out to be paraphyletic with 
respect to Craseonycteridae).

     It is sort of like (although to a lesser degree) the loss of the 
aardvark compared to the loss of one species of the genus Rattus.  The loss 
of a single species of Rattus would not be equivalent to the loss of a 
monotypic genus of mammal (much less an entire Family or Order).  
Conservation efforts should have some recognition of this with a sort of 
"triage" giving somewhat greater attention to species within species-poor 
taxa (i.e., "phylogenetically isolated" species as Bob refers to them below) 
over species within species-rich taxa.
   ----Cheers,
            Ken Kinman

*******************************
From : Bob Mesibov <mesibov at southcom.com.au>
To : <kinman at hotmail.com>
Subject : Re: Article on poaching newly described species in current issue 
of The Chronicle of Higher Education

Ken Kinman wrote on TAXACOM:
"After all, there is only one extant species in Family Craseonycteridae, so 
it would be the extinction of an entire Family (thus a bigger chunk of 
biodiversity than in most cases)."

Ken, this is a very interesting use of the word "biodiversity". It's a use 
allied to the argument that phylogenetically isolated species should be 
given a higher priority in conservation. Could you expand on just what you 
mean by "biodiversity" here?
(I haven't sent this to TAXACOM, but you're welcome to copy my msg in a 
posting there if you think the topic needs discussing.)
Cheers,
Bob
---
Dr Robert Mesibov