I nissed the post that Glen refers to. Could someone forward me another
copy? From what Glen says, I assume that either it or Peter Milburn
defended splits, particularly those proposed for the Albatrosses on the
basis of helping conservation. I am glad to help conservation, but I
wouldn't distort scientific facts for that or any other reason.
I see the splits as justified because mtDNA sequencing is at last providing
us with reasonably definitive in the area of species limits. More often
than not, this contradicts traditional species limits based on the
biological species concept. As Jurgen Haffer has pointed out in the recent
BOC Centenary Volume, the BSC is applicable only strictly speaking to
sympatric or at least parapatric taxa. It has nothing whatsoever so say
about allopatric taxa, and in such cases requires us to fall back on the
analyst's "inference".
Even the existence of interbreeding is no longer strong evidence for
conspecificity. How many proposals are there to merge Pacific Black Duck
with Mallard?
I also feel very strongly that Julian Ford's lumping of the Nullarbor
Quail-thrush C.alisteri with Cinnnamon Quail-thrush, C.cinnamomeum was
wrong, as was his uniting of the Western Quail-thrush C.marginatum, with the
Chestnut-breasted Quail-thrush, C.castaneothorax of sQld and nNSW. The
latter is contrary to any conceptualisation of species in terms of gene
flow. You can either keep castaneothorax, cinnamomeum and marginatum as
subspecies of one species, or have each as a separate species. I agree with
his splitting of castaneothorax. But you can't logically join the taxa at
the two ends. This appears to be an instance of the Leap-frog pheonomen
studied by van Remsen and others in the Andes. There are many groups where
the forms in Colombia and Peru are more similar to each other than either is
to the intervening form in Ecuador. Yet Remsen says that in every case, the
more distant forms are genetically more distant from each other than either
is from the apparnetly more different intermediate form. Appearance is a
function of only part of the genome.
In the case of the Nullarbor Quail-thrush, it does not interbreed with
cinnamomeum (it is wholly allopatric), it looks different, and it inhabits
different habitat. I would say that prima facie, it should be kep as a
separate species unless someproves from DNA sequencing that the two should
be merged.
I am also unimpressed by Ford's methodology. The parameters that he
measured were all either at the nominal or at beast the ordinal level of
measurement. This means that even if we accept the shapes of his trees, we
don't know what the differences are in absolute terms.
In fact, apart from the computer packages he used, Ford's choice of criteria
are similar to those used by Gadow in the nineteenth century!
Although I do not accept the Phylogenetic Species Concept lock stock and
barrel (which version?), I think that it is in general a sounder approach
than the BSC, and one which increasingly supported by molecular evidence.
John Penhallurick
At 12:16 11/08/98 +1000, you wrote:
>Three cheers for David! What an excellent summary of the confusing
>kaleidoscope of albatross species. However, I do respect Peter Milburn's
>arguments.
>
>As for fiddling with nomenclature to enhance conservation, someone is going
>to eventually mount a legal challenge that will burst asunder any
>credibility the conservation of species ever had. That will be a sad day.
>It is fine for the moment as a grant enhancer and work funder within the
>government and conservation industries (more species more urgent and
>expensive work needed in an important, popular group).
>
>But the dangers loom. And while money is channelled into this sort of work,
>habitat is being cleared everywhere. I think there is a good argument for
>stopping all grants and work on species, closing down the conservation
>industry and channelling all their moneys into land acquisition.
>
>
>Even so, the rush for Evolutionary Terminal Taxa, Operational Taxonomic
>Units, or Cultural Terminal Taxa of ethnosystematics, tends to forget the
>range of clients for nomenclature. It is useless producing classifications
>if these cannot be used by most of them. We are getting to the level of
>Betty and Harry Albatross. This is your future:
>
>Tony Palliser's Pelagic Report for 12 July, 1999, Sydney Boat Trip.
>
>A great day was had by all even if the numbers of birds were down on last
>trip. Only 334,000 species were seen but that was because of the calm seas.
>Please use an unzipping file to access the list.
>
>1. Betty Albatross
>2. Harry Albatross
>3. Cilia Black Petrel
>4. Robin Shearwater
>5. Craig Shearwater
>6. Betty Shearwater
>7. John Shearwater
>8. Alan Shearwater
>9. Trevor Shearwater
>10. Tom Shearwater (shearwater species continued on pages 233-10987).
>11. Annie Prion
>etc
>
>However, it is sad to report we found a dead bird: Barry Albatross has
>become extinct despite all the conservation efforts of Environment
>Australia, Birds Australia, Greening Austraila, Wildlife Australia and the
>sponsorship of Tennis Australia.
>
>
>Glen
>
>Brisbane, Australia
>
>
>
>
>
Associate Professor John M. Penhallurick<>
Canberra, Australia
Phone BH( 61 2) 6201 2346 AH (61 2) 62585428
FAX (61 2) 6258 0426
Snail Mail Faculty of Communication
University of Canberra,A.C.T.2601, AUSTRALIA
OR PO Box 3469, BMDC, BELCONNEN, ACT 2617, AUSTRALIA
"I'd rather be birding!"
"Vivat,crescat,floreat Ornithologia"
Hartert,Vog.pal.Fauna,p.2016.
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