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SAUROPOD TRACKS, BIRD PAPERS etc
The following just in. Apologies if some have been reported
Padian, K. & Horner, J. R. 2002. Typology versus
transformation in the origin of birds. _Trends in Ecology &
Evolution_ 17, 120-124.
Essentially a critique of claims from the Ruben et al camp
and proposes that arguments about 'reptilian'-style
physiology/behaviour in non-avian dinosaurs are naïve in
that they hang on to a 19th century typological approach.
Some of the points here are those made by Makovicky and
Dyke in the 'Naive falsification' paper. Good review of
current thoughts on egg-laying, nesting and brooding
Day, J. J., Upchurch, P., Norman, D. B., Gale, A. S. &
Powell, H. P. 2002. Sauropod trackways, evolution, and
behavior. _Science_ 296, 1659.
A Bathonian sauropod trackway site from the White-
Limestone Formation at Ardley Quarry, Oxfordshire,
reveals 40 subparallel trackways representing both narrow-
and wide-gauge sauropods. The absence of a hallux
impression supports ID of the wide-gauge tracks as
titanosaurian.. thus support for titanosauriform
diversification by this time. Seeing as two kinds of
sauropods are seen walking side by side, this is also
evidence for mixed-species herds. Incidentally this is the
same site that produced the running theropod track reported
in _Nature_ earlier this year (Day et al., _Nature_ 415, 494).
Clegg, S. M. & Owens, I. P. F. 2002. The 'island rule' in
birds: medium body size and its ecological
explanation._Proc. R. Soc. London_ B 269, 1359-1365.
Birds are traditionally not thought to follow the 'island rule'
as mammals do (viz: big species produce dwarf
descendants, small species produce giant descendants) and
instead just grow bigger bills. Clegg et al test this and find
that previous studies were passerine-biased (Grant's work
proved highly influential) - 80% of comparisons in previous
studies were based on passerine species (which shows the
bias as passerines 'only' constitute 59% of extant bird
species). When things are evened out, the island rule _is_
observed, and both in body size and bill length. Multiple
ecological factors must contribute to adoption of the island
rule and this study paves the way for their recognition.
Edwards, S. V. & Boles, W. E. 2002. Out of Gondwana: the
origin of passerine birds. _Trends in Ecology & Evolution_
Two recent studies of passerines - Barker et al. (2002,
_Proc. R. Soc. Lond._ B 269, 295-308) and Ericson et al.
(2002, _Proc. R. Soc. Lond._ B 269, 235-241) - agree that
NZ wrens (acanthisittids) are the sister-group to all other
passerines and that Corvida is paraphyletic with respect to
Passerida. Edwards and Boles discuss the biogeographical
implications of this as - combined with the evidence from
the fossil record and the established Gondwanan ancestry of
suboscines - it emphasises a Gondwanan origin for
Passeriformes and, more specifically, supports eastern
Gondwana (Australia and New Guinea) as the centre of
origin for passerines. As they argue, this also supports a
Cretaceous origin for passerines and thus for other
Incidentally there are some really funny things happening in
passerine biogeography (if you have been following
Michael Heads' recent papers on bowerbirds and BsOP):
namely that, firstly, vicariance is the main factor and,
secondly, that the disjunct distribution of species groups
indicates substantially older diversifications than those we
might prefer based on other lines of evidence. And while
birds may be supreme dispersalists, there is every indication
that some groups are sedentary to the absurd.
de Klerk, H. M., Crowe, T. M., Fjeldsa, J. & Burgess, N. D.
2002. Patterns of species richness and narrow endemism of
terrestrial bird species in the Afrotropical region. _J. Zool._
Preliminary versions of this study have been produced by
Burgess et al. (1997, _Bull. ABC_ 4, 93-98; 2000,
_Ostrich_ 71, 286-290). Areas of greatest species richness
in the Afrotropical region largely correlate with areas of
narrow endemism and are the mountains and mountain-
lowland complexes of the East African rift system, the
Cameroon-Bamenda Highland system and the Eastern Arc
mountains. However, some areas of highest narrow
endemism are _not_ species richness peaks. The former are
historically of great biogeographical importance as they are
so-called 'species pumps'. Recognition of the difference
between peaks of species richness and narrow endemism
obviously has implications for conservation priorities.
Pisani et al's recent dinosaur supertree paper cited pretty
much all of the papers on supertrees produced by Olaf
Bininda-Emonds and his team (as did Walsh and Naish
2002 I suppose). The latest paper to be produced by the
Jones, K. E., Purvis, A., MacLarnon, A., Bininda-Emonds,
O. R. P. & Simmons, N. B. 2002. A phylogenetic supertree
of the bats (Mammalia: Chiroptera). _Biol. Rev._ 77, 223-
If I attempt a summary this email will take more time than I
have. Mega and microbats are monophyletic, microbat
paraphyly not supported.
Finally, for those interested in cetaceans, a third specimen
of Longman's beaked whale has just been reported from
South Africa. DNA studies confirm that two previous South
African carcasses (one from the early 1980s, the other 1992)
were also of this species (recall that it is otherwise known
only from three skulls).
What the hell, may as well report these...
Dalebout, M. L., Mead, J. G., Baker, C. S., Baker, A. N. &
van Helden, A. L. 2002. A new species of beaked whale
_Mesoplodon perrini_ sp. n. (Cetacea: Ziphiidae)
discovered through phylogenetic analyses of mitochondrial
DNA sequences. _Marine Mammal Science_ 18, 577-608.
van Helden, A. L., Baker, A. N., Dalebout, M. L., Reyes, J.
C., Van Waerebeek, K. & Baker, C. S. 2002. Resurrection
of _Mesoplodon traversii_ (Gray, 1874), senior synonym of
_M. bahamondi_ Reyes, Van Waerebeek, Cárdenas and
Yáñez, 1995 (Cetacea: Ziphiidae). _Marine Mammal
Science_ 18, 609-621.
Boo-hoo, goodbye _M. bahamondi_. I still say Dalebout et
al. should have cited...
Naish, D. 1998. A possible new species of ziphiid whale.
_The Cryptozoology Review_ 3 (2), 25-28.
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL
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