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Happy New Papers!



OK, so it's not a movie title, but...  Thanks to DF and SP for some of these
refs!



Buffetaut, E., and Suteethorn, V. 2007. A sinraptorid theropod (Dinosauria:
Saurischia) from the Phu Kradung Formation of northeastern Thailand.
Bulletin de la Société Géologique de France 178(6):497-502.

ABSTRACT: A theropod tibia from the Phu Kradung Formation of Mukdahan
Province, northeastern Thailand, is described and referred to the family
Sinraptoridae, previously known only from the Jurassic of China (Xinjiang
and Sichuan). This find confirms the affinities of the vertebrate assemblage
from the Phu Kradung Formation with Late Jurassic faunas from China. The
Late Jurassic age suggested by fossil vertebrates for the Phu Kradung
Formation is not in good agreement with an attribution to the Early
Cretaceous based on palynomorphs.




Hua, S., Buffetaut, E., Legall, C., and Rogron, P. 2007. Oceanosuchus
boecensis n. gen., n. sp., a marine pholidosaurid (Crocodylia, Mesosuchia)
from the Lower Cenomanian of Normandy (western France). Bulletin de la
Société Géologique de France 178(6):503-513.

ABSTRACT: A partial crocodilian skeleton, including a well-preserved skull
and mandible, from the marine Lower Cenomanian of Normandy (northwestern
France) is described as a new genus and species of the family
Pholidosauridae (Mesosuchia), Oceanosuchus boecensis. Diagnosis for genus
and species: Mesorostrine pholidosaurid (rostral index 66% as compared with
74% for Terminonaris robusta and 75% for Sarcosuchus imperator, hitherto the
least longirostrine species in that family), relatively short mandibular
symphysis (11 post-symphysial alveoli), no external mandibular fenestra,
prearticular present, paired tuberosities at the base of the cervical
vertebral centra.



Griffin, D.K., Robertson, L.B.W., Tempest, H.G., and Skinner, B.M. 2007. The
evolution of the avian genome as revealed by comparative molecular
cytogenetics. Cytogenetic & Genome Research 117(1-4):64-77. doi:
10.1159/000103166.

ABSTRACT: Birds are characterised by feathers, flight, a small genome and a
very distinctive karyotype. Despite the large numbers of chromosomes, the
diploid count of 2n ? 80 has remained remarkably constant with 63% of birds
where 2n = 74?86, 24% with 2n = 66?74 and extremes of 2n = 40 and 2n = 142.
Of these, the most studied is the chicken (2n = 78), and molecular
cytogenetic probes generated from this species have been used to further
understand the evolution of the avian genome. The ancestral karyotype is, it
appears, very similar to that of the chicken, with chicken chromosomes 1, 2,
3, 4q, 5, 6, 7, 8, 9, 4p and Z representing the ancestral avian chromosomes
1?10 + Z; chromosome 4 being the most ancient. Avian evolution occurred
primarily in three stages: the divergence of the group represented by extant
ratites (emu, ostrich etc.) from the rest; divergence of the Galloanserae
(chicken, turkey, duck, goose etc.) ? the most studied group; and divergence
of the ?land? and ?water? higher birds. Other than sex chromosome
differentiation in the first divergence there are no specific changes
associated with any of these evolutionary milestones although certain
families and orders have undergone multiple fusions (and some fissions),
which has reduced their chromosome number; the Falconiformes are the best
described. Most changes, overall, seem to involve chromosomes 1, 2, 4, 10
and Z where the Z changes are intrachromosomal; there are also some
recurring (convergent) events. Of these, the most puzzling involves
chromosomes 4 and 10, which appear to have undergone multiple fissions
and/or fusions throughout evolution ? three possible hypotheses are
presented to explain the findings. We conclude by speculating as to the
reasons for the strange behaviour of these chromosomes as well as the role
of telomeres and nuclear organisation in avian evolution.



Ellegren, H. 2007. Molecular evolutionary genomics of birds. Cytogenetic &
Genome Research 117(1-4):120-130. doi: 10.1159/000103172.

ABSTRACT: Insight into the molecular evolution of birds has been offered by
the steady accumulation of avian DNA sequence data, recently culminating in
the first draft sequence of an avian genome, that of chicken. By studying
avian molecular evolution we can learn about adaptations and phenotypic
evolution in birds, and also gain an understanding of the similarities and
differences between mammalian and avian genomes. In both these lineages,
there is pronounced isochore structure with highly variable GC content.
However, while mammalian isochores are decaying, they are maintained in the
chicken lineage, which is consistent with a biased gene conversion model
where the high and variable recombination rate of birds reinforces
heterogeneity in GC. In Galliformes, GC is positively correlated with the
rate of nucleotide substitution; the mean neutral mutation rate is
0.12-0.15% at each site per million years but this estimate comes with
significant local variation in the rate of mutation. Comparative genomics
reveals lower dN/dS ratios on micro- compared to macrochromosomes, possibly
due to population genetic effects or a non-random distribution of genes with
respect to chromosome size. A non-random genomic distribution is shown by
genes with sex-biased expression, with male-biased genes over-represented
and female-biased genes under-represented on the Z chromosome. A strong
effect of selection is evident on the non-recombining W chromosome with high
dN/dS ratios and limited polymorphism. Nucleotide diversity in chicken is
estimated at 4-5 × 10-3 which might be seen as surprisingly high given
presumed bottlenecks during domestication, but is lower than that recently
observed in several natural populations of other species. Several important
aspects of the molecular evolutionary process of birds remain to be
understood and it can be anticipated that the upcoming genome sequence of a
second bird species, the zebra finch, as well as the integration of data on
gene expression, shall further advance our knowledge of avian evolution.



Tobalske, B.W., and Biewener, A.A. 2008. Contractile propoerties of the
pigeon supracoracoideus during different modes of flight. Journal of
Experimental Biology 211(2):170-179. doi: 10.1242/jeb.007476.

ABSTRACT: The supracoracoideus (SUPRA) is the primary upstroke muscle for
avian flight and is the antagonist to the downstroke muscle, the pectoralis
(PECT). We studied in vivo contractile properties and mechanical power
output of both muscles during take-off, level and landing flight. We
measured muscle length change and activation using sonomicrometry and
electromyography, and muscle force development using strain recordings on
the humerus. Our results support a hypothesis that the primary role of the
SUPRA is to supinate the humerus. Antagonistic forces exerted by the SUPRA
and PECT overlap during portions of the wingbeat cycle, thereby offering a
potential mechanism for enhancing control of the wing. Among flight modes,
muscle strain was approximately the same in the SUPRA (33?40%) and the PECT
(35?42%), whereas peak muscle stress was higher in the SUPRA (85?126 N m?2)
than in the PECT (50?58 N m?2). The SUPRA mainly shortened relative to
resting length and the PECT mainly lengthened. We estimated that elastic
energy storage in the tendon of the SUPRA contributed between 28 and 60% of
the net work of the SUPRA and 6?10% of the total net mechanical work of both
muscles. Mechanical power output in the SUPRA was congruent with the
estimated inertial power required for upstroke, but power output from the
PECT was only 42?46% of the estimated aerodynamic power requirements for
flight. There was a significant effect of flight mode upon aspects of the
contractile behavior of both muscles including strain, strain rate, peak
stress, work and power.



Taylor, G.K., Bacic, M., Bomphrey, R.J., Carruthers, A.C., Gillies, J.,
Walker, S.M., and Thomas, A.L.R. 2008. New experimental approaches to the
biology of flight control systems. Journal of Experimental Biology
211(2):258-266. doi: 10.1242/jeb.012625.

ABSTRACT: Here we consider how new experimental approaches in biomechanics
can be used to attain a systems-level understanding of the dynamics of
animal flight control. Our aim in this paper is not to provide detailed
results and analysis, but rather to tackle several conceptual and
methodological issues that have stood in the way of experimentalists in
achieving this goal, and to offer tools for overcoming these. We begin by
discussing the interplay between analytical and empirical methods,
emphasizing that the structure of the models we use to analyse flight
control dictates the empirical measurements we must make in order to
parameterize them. We then provide a conceptual overview of tethered-flight
paradigms, comparing classical `open-loop' and `closed-loop' setups, and
describe a flight simulator that we have recently developed for making
flight dynamics measurements on tethered insects. Next, we provide a
conceptual overview of free-flight paradigms, focusing on the need to use
system identification techniques in order to analyse the data they provide,
and describe two new techniques that we have developed for making flight
dynamics measurements on freely flying birds. First, we describe a technique
for obtaining inertial measurements of the orientation, angular velocity and
acceleration of a steppe eagle Aquila nipalensis in wide-ranging free
flight, together with synchronized measurements of wing and tail kinematics
using onboard instrumentation and video cameras. Second, we describe a
photogrammetric method to measure the 3D wing kinematics of the eagle during
take-off and landing. In each case, we provide demonstration data to
illustrate the kinds of information available from each method. We conclude
by discussing the prospects for systems-level analyses of flight control
using these techniques and others like them.



de Vasconcellos, F.M., and de Souza Carvalho, I. 2007. Cranial features of
Baurusuchus salgadoensis Carvalho, Campos & Nobre 2005, a Baurusuchidae
(Mesoeucrocodylia) from the Adamantina Formation, Bauru Basin, Brazil:
paleoichnological, taxonomic and systematic implications; pp. 319-332 in de
Souza Carvalho, I., Cassab, R.C.T., Schwanke, C., Carvalho, M.A., Fernandes,
A.C.S., Rodrigues, M.A.C., Carvalho, M.S.S., Arai, M., and Oliveira, M.E.Q.
(eds.), Paleontologia: Cenàrios de Vida Vol. 1. Editoria Interciência, Rio
de Janeiro.

ABSTRACT: Some features of the skull of Baurusuchus salgadoensis Carvalho,
Campos & Nobre 2005, a baurusuchid Mesoeucrocodylia from the Adamantina
Formation of Bauru Basin, are described, discussed and reinterpreted. The
punctures and perforations of the skull of B. salgadoensis, one of them
previously described as the antobital fenestrae, were interpreted as
tooth-marks. The probable producer is a medium or large ziphodont
terrestrial archosaur, possibly a baurusuchid or Abelisauridae. The choanae
of B. salgadoensis bears some similarities with Stratiotosuchus. The choanae
and the palatal surfaces seem to be similar among baurusuchids, notosuchids
and sphagesaurids with minor differences. This similarity is congruent with
recent phylogenetic hypotheses, supporting a closer relationship among these
Creataceous Mesoeucrodylia taxa.

     ...anyone know of a North American distributor/source for this and its
companion volume...?


Frey, E., and Salisbury, S.W. 2008. Crocodilians of the Crato Formation:
evidence for enigmatic species; pp. 463-474 in Martill, D.M., Bechly, G.,
and Loveridge, R.F. (eds.), The Crato Fossil Beds of Brazil: Window Into an
Ancient World. Cambridge University Press, Cambridge.

     ...no, I don't have this book yet, but it's got chapters on all the
other tetrapods from the unit, including birds.




Lindow, B.E.K., and Dyke, G.J. 2007. A small galliform bird from the Lower
Eocene Fur Formation. Bulletin of the Geological Society of Denmark
55:59-63.

ABSTRACT: A pair of fossilized imprints of feet represent the first
published galliform (landfowl) specimen from the Lower Eocene Fur Formation
of northwest Denmark. The specimen is referable to Galliformes due to the
presence of a distinctly asymmetric trochlea metatarsi III. The specimen
appears distinct from previously described Eocene Galliformes (e.g.
Gallinuloididae, Quercymegapodiidae and Paraortygidae) and may represent a
new taxon of Galliformes, increasing the diversity of this group in the
Lower Eocene.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
 and     dinogami@gmail.com
http://cactus.dixie.edu/jharris/

"There's a saying that goes 'people who live in glass houses shouldn't throw
stones'... OK. How about...NOBODY should throw stones. That's crappy
behavior! My policy is 'no stone-throwing regardless of housing situation.'
There's an exception, though. If you're TRAPPED in a glass house...and you
have a stone, then throw it! What are you, an idiot? It's really 'ONLY
people in glass houses should throw stones'... provided they're trapped, in
a house... with a stone. It's a little longer, but you know..."
                                 --- Demetri Martin