Drosophila Hydei A molecular evolutionary phylogenetic study

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Drosophila Hydei A molecular evolutionary
phylogenetic study

• Aurash Kamalipour
• Biochemistry Undergraduate
• October 21, 2009
• Dan Graur
• Ex scientia fiducia in toto

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Drosophila, Do the dew.

• The name Drosophila comes from Latin, meaning
  dew lover.
• Drosophila is everywhere deserts, alpine zones,
  tropical climates, swamps, and urban areas just
  to name a few.
• Drosophila larvae eat yeast which grows in
  fermenting fruit as such Drosophila (aka vinegar
  flies) are attracted to signs of fermentation
  e.g. vinegar formation.
• The genuss phylogenetic relationships are very
  poorly understood Currently the Drosophila genus
  is paraphyletic there are around 1500 KNOWN
  species of Drosophila (out of possibly 5000)
  and it has many multifurcated points. Ergo, the
  phyllogram IMHO is JUNK.

Drosophila hydei
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Too normal to live, too common to
dieDrosophilas diversity destroys discernment
of defining distinctions.
In other words, the Drosophila genus (which
encompasses the Sophophora subgenus, et al.) is
devoid of any one special defining characteristic
which could help define the phylogenetic
relationships of the subgroups/species in one
subgenus between any of the subgroups/species in
another subgenus. Drosophila traits are all
mixed between all species, regardless of
subgenus assortment. This means that we cannot
rely on phenotype based characterization as a
measure of evolutionary relationship but we knew
that already, didnt we? Currently the
evolutionary relationships between these
different flies are being elucidated through a
concerted composition of data and molecular
evolutionary techniques. A Drosophila genome
sequencing project is underway the nuclear and
mitochondrial genes of the different flies are
analyzed (using ME techniques1) to provide us
with more telling insights on the true ancestral
neighbors in this medley of myia
(flies). Theories are abound on what caused the
diversity in Drosophila. .. The fact that they
are small, ubiquitous, and short-lived means they
are subject to stronger evolutionary forces and
speciation.
1 Techniques used were NJ and MP phylogeny tree
building using homologous genes which have been
properly mapped and aligned.
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What do we care?
What is known Drosophila subgenre are being
sequenced and categorized, with hopes that the
distinctions between each genus can be accurately
defined by evolutionary relationships, and
perhaps even relevance. What remains to be
known The breadth of the Drosophila genus
remains to be discovered and far exceeds what
weve already documented (much less sequenced),
but in spite of that, we stand to benefit from a
better understanding the nature of
evolution/speciation. Through studying such
rapid-evolving species (with many homologous
human disease states) we may eventually be better
able to accurately characterize forces, define
parameters and algorithmically model the extent
through which the natural world acts as
modulators to speciation.
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References
Evolution of genes and genomes on the drosophila
phylogeny. Nature , 450 (7167), 2007, 203-218.
http//dx.doi.org/10.1038/nature06341Tomas
Moran, Antonio Fontdevila, On the phylogeny of
the Drosophila hydei subgroup New insights from
combined analyses of nuclear and mitochondrial
data, Molecular Phylogenetics and Evolution,
Volume 43, Issue 3, June 2007, Pages 1198-1205,
ISSN 1055-7903, DOI 10.1016/j.ympev.2006.12.021.
Tomas Moran, Antonio Fontdevila, Phylogeny and
molecular evolution of the Drosophila hydei
subgroup (Drosophila repleta group) inferred from
the Xanthine dehydrogenase gene, Molecular
Phylogenetics and Evolution, Volume 36, Issue 3,
September 2005, Pages 695-705, ISSN 1055-7903,
DOI 10.1016/j.ympev.2005.04.009.
Suppose we could know the nature of speciation as
defined by a series of definite, definable
parameters which are invariably used in an
empirically-supported algorithm of evolution.