Dear Scot and others,
in response to the question about the taxonomic placement of Artamidae
(press delete if not interested in taxonomy):
Sibley and Alhquist indeed placed all the woodswallows, currawongs,
Australian magpies etc inside the subfamily Corvinae along with typical
crows (=their tribe Corvini), cuckooshrikes, Old World orioles and
birds-of-paradise. Conversely, the true magpies (Pica) have always been
considered as belonging to the true crows (i.e. family Corvidae, which
Sibley and Ahlquist relegated to the rank of a "tribe" Corvini), along with
other "crow and jay" genera such as Corvus (real crows), Garrulus etc
(jays), nutcrackers (Nucifraga) and others.
Since the days of traditional morphology-based taxonomy and Sibley and
Ahlquist's DNA-DNA hybridization, however, we have come a long way! At this
point, it is important to recognize the differences between Sibley and
Ahlquist's DNA-DNA hybridization approach of the 80s and 90s, which few if
any scientists continue to use, and modern DNA sequence based methods. Many
field birders tend to accept (or refuse) the results of both these
methodologies with equal readiness. However, it is important to be aware of
the differences in resolving power and accuracy. Sibley and Ahlquist's
hybridization approach is (better: was) a distance-based method, in which
DNA double strands are degenerated (by heating) and re-married to the
strands of the species to be compared. There is a whole body of literature
about the pro's and con's of this method. However, some of the criticisms of
this approach involve such things as: 1.) high error rate, 2.) the method
does not compare characters of the species involved (as traditional taxonomy
or modern DNA sequence based methods do), but distances (i.e. the time it
takes for two DNA strands from different species to re-anneal = to
re-marry), 3.) the fact that hybridization analyses (which are very
time-intensive) must be pairwise (i.e. Sibley and Ahlquist only compared
Artamidae to those families they most suspected to be closely related;
modern results show that the true sister groups were never even taken into
consideration by Sibley and Ahlquist).
Meanwhile, DNA sequences have been generated and compared for Artamidae by
several study groups (e.g. two important publications by Keith Barker et
al., plus a very recent paper by Jerome Fuchs et al., ask me for references
off-list if interested), which all converge on the same results: Artamidae
and Cracticidae actually sit in with a group of strictly African songbirds,
encompassing the bush-shrikes (unrelated to true shrikes!), tchagras,
helmet-shrikes, vangas (from Madagascar), batisses and wattle-eyes. This
hitherto unrecognized bird clade also includes a fair sprinkle of Asian
genera that have so far been of equivocal placement, such as ioras,
philentomas and flycatcher-shrikes.
In contrast, traditional taxonomy, Sibely/Ahlquist and modern DNA studies
all agree about the placement of Pica magpies with the true
crows/ravens/jays.
This is one of the few cases where Eurocentric classification of the 19th
century turned out to be correct (mostly it was wrong, considering that such
concepts as "warbler", "oriole", "sparrow", "finch" etc have all lost part
of their meaning in post-DNA times).
When I moved to Australia 3 years ago and was first confronted with
currawongs and Australian Corvus species, I remember how my intuition also
misled me into thinking that these must be closely related, especially since
all Australian Corvus crows/ravens are so different from their American and
Eurasian counterparts with respect to their light eyes and peculiar vocal
behaviour. However, it turns out looks can be deceiving...
All the best
Frank
---------------------------------------------
============Frank E. RHEINDT================
DEPARTMENT OF GENETICS
University of Melbourne
POSTAL ADDRESS:
Museum Victoria - Sciences Department
GPO Box 666
Melbourne 3001
Victoria
Australia
Telephone: 8341 7426
Fax: 8341 7442
E-Mail:
LL: 4181 (Gra.pic.)
=============================================
From: Scot Mcphee <>
To: birding-aus aus <>
Subject: [Birding-Aus] Corvidae & Artamidae
Date: Sat, 17 Feb 2007 11:20:51 +1000
Can I ask a question?
Why are the Artamidae not regarded as Corvidae and yet Northern Hemisphere
birds such as Jays, Jackdaws, European Magpies and the like are? If any
one saw a line up from Australian Raven, Little Crow, Pied Currawong,
Australian Magpie, Pied Butcherbird, Grey Butcherbird the relationship is
easily determined to the eye. I understand DNA evidence may suggest
otherwise but doesn't Sibley and Alhquist say they are related?
Are European Magpies really more closely related to crows than the
Currawong? This has always seems preposterous me, just another hangover of
hopelessly Euro-centric thinking in 18th century naturalists.
--
Autonomous Organisation
http://www.autonomous.org/
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