New in Cladistics

["Jaime A. Headden" <qilongia@yahoo.com>]

http://www.blackwell-synergy.com/links/doi/10.1111/j.1096-0031.2004.00048.x

  Pickett, K. M. 2005. The new and improved PhyloCode, now with types,
    ranks, and even polyphyly: a conference report from the First
    International Phylogenetic Nomenclature Meeting. _Cladistics_ 21(1):
    [posted online before print, no page numbers]
    (doi:10.1111/j.1096-0031.2004.00048.x)

Abstract:
  "A report from the first International Phylogenetic Nomenclature Meeting
   is presented. The meeting revealed that the PhyloCode, once
implemented,
   will itself not require adherence to the three major tenets of
   philosophy that proponents have claimed required its creation. These
   include the abandonment of (1) non-monophyletic taxa, (2) ranks, and
(3)
   types."

--

  Debruyne, R. 2005. A case study of apparent conflict between molecular
    phylogenies: the interrelationships of African elephants. _Cladistics_
    21(1): [posted online before print, no page numbers]
   (doi:10.1111/j.1096-0031.2004.00044.x)
 
Abstract:
  "Recent molecular phylogenies of the African elephants suggest that
there
   is an evolutionary structure within *Loxodonta africana*. Some nuclear
   results (Roca et al., 2001) support the separation of the forest
African
   elephant subspecies *L. a. cyclotis* as a species distinct from the
   savannah elephant *L. a. africana*, on the basis of the recognition of
   both forming highly divergent (reciprocally monophyletic) clades.
   Conversely, a mitochondrial survey (Eggert et al., 2002), while
   admitting a geographic partitioning of the genetic structure within
   African elephants, suggests retaining the status quo. They recognize
   three diagnosible entities (western, central and south-eastern Africa)
   with non-overlapping ranges within *L. africana* _sensu lato_. In order
   to address these conflicting views (historical fragmentation and
   speciation or isolation by distance, respectively), we have sequenced
   two datasets of 1961 bp (for 50 elephants) and about 3700 bp,
   respectively (for 20 elephants) of the mitochondrial DNA for both forms
   of elephants (*cyclotis* and *africana*). They span the cytochrome _b_
   gene, the control region and several RNAs. When compared with former
   mtDNA data, they provide the most comprehensive view of the African
   elephant phylogeny (78 mtDNA haplotypes, of which 44 are new) and
   provide the first insight into populations from the Democratic Republic
   of Congo. The genetic diversity of mtDNA was appraised and the
stability
   of alternative phylogenetic trees was investigated. Our results are
   inconsistent with both those prior studies. They revealed two highly
   divergent molecular clades referred to as F and S, that do not conform
   to the morphological delineations of cyclotis and africana. A
   non-negligible proportion of specimens of *L. a. africana* display
   haplotypes prevailing in forest elephant populations (clade F). The
   geographic distribution of clades and areas of their co-occurrence
   support the hypothesis of incomplete isolation between forest and
   savannah African elephant populations, followed by recurrent
   interbreeding between the two forms. We state that the conclusions of
   prior studies resulted from insufficient character and/or geographic
   sampling. We conclude that there is no satisfying argument which can
   recognize two or more species of African elephants. We briefly comment
   on the meaning of such an attitude in a conservation viewpoint."

  Cheers,

Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)


                
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