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Alice in New Papersland



Nagashima, H., Sugahara, F., Takechi, M., Ericsson, R., Kawashima-Ohya, Y.,
Narita, Y., and Kuratani, S. 2009. Evolution of the turtle body plan by the
folding and creation of new muscle connections. Science 325:193-196. doi:
10.1126/science.1173826.

ABSTRACT: The turtle shell offers a fascinating case study of vertebrate
evolution, based on the modification of a common body  plan. The carapace is
formed from ribs, which encapsulate the scapula; this stands in contrast to
the typical amniote body plan  and serves as a key to understanding turtle
evolution. Comparative analyses of musculoskeletal development between the
Chinese soft-shelled turtle and  other amniotes revealed that initial turtle
development conforms to the amniote pattern; however,  during embryogenesis,
lateral rib growth results in a shift of  elements. In addition, some limb
muscles establish new  turtle-specific attachments associated with carapace
formation. We propose that the evolutionary origin of the turtle body  plan
results from heterotopy based on folding  and novel connectivities.




Phillips, M.J., Gibb, G.C., Crimp, E.A., and Penny, D. 2010. Tinamous and
moa flock together: mitochondrial genome sequence analysis reveals
independent losses of flight among ratites. Systematic Biology 59(1):90-107.
doi: 10.1093/sysbio/syp079.

ABSTRACT: Ratites  are large, flightless birds and  include the ostrich,
rheas, kiwi, emu, and cassowaries, along with extinct members, such as moa
and elephant birds. Previous phylogenetic analyses of complete mitochondrial
genome sequences have reinforced the traditional belief that ratites are
monophyletic and  tinamous  are their sister group. However, in these
studies ratite monophyly was enforced in the analyses that modeled rate
heterogeneity among variable sites. Relaxing this topological constraint
results in strong support for the tinamous (which fly) nesting within
ratites. Furthermore, upon reducing base compositional bias and partitioning
models of sequence evolution among protein codon positions and  RNA
structures, the tinamou?moa clade grouped with kiwi, emu, and cassowaries to
the exclusion of the successively more divergent rheas and  ostrich. These
relationships are consistent with recent results from a large nuclear data
set, whereas our strongly supported finding of a tinamou?moa grouping
further resolves palaeognath phylogeny. We infer flight to have been lost
among  ratites  multiple times in temporally close association with the
Cretaceous?Tertiary extinction event. This circumvents requirements for
transient microcontinents and island chains to explain discordance between
ratite phylogeny and patterns of continental breakup. Ostriches may have
dispersed to Africa from Eurasia, putting in question the status of ratites
as an iconic Gondwanan relict taxon.




Lü, J. 2010. A new boreopterid pterodactyloid pterosaur from the Early
Cretaceous Yixian Formation of Liaoning Province, northeastern Chian. Acta
Geologica Sinica (English Edition) 84(2):241-246.

ABSTRACT: A new boreopterid pterosaur: Zhenyuanopterus longirostris gen. et
sp. nov. from the Yixian Formation of western Liaoning is erected, based on
the complete skeleton with a skull and lower jaws preserved. It is
characterized by: a large boreopterid pterosaur with a high number of teeth,
where the anterior teeth are much larger than posterior ones; the length of
the dorsal + sacral vertebrae is nearly half the length of the skull; ratio
of the length of the humerus to metacarpal IV is approximately 91% and the,
humerus, femur and third wing phalanx are all equal in length and the feet
are specially small. It represents the largest boroepterid pterosaur
discovered from western Liaoning and its surrounding areas so far




Wang, X., O?Connor, J.K., Zhao, B., Chiappe, L.M., Gao, C., and Cheng, X.
2010. New species of Enantiornithes (Aves: Ornithothoraces) from the Qiaotou
Formation in northern Hebei, China. Acta Geologica Sinica (English Edition)
84(2): 247-256.

ABSTRACT: We report on a new species of enantiornithine bird from the Lower
Cretaceous Qiaotou Formation of northern Hebei, China. The new taxon,
Shenqiornis mengi gen. et sp. nov., possesses several enantiornithine
synapomorphies but is unique from other known species. The specimen has a
well-preserved skull that reveals new information about enantiornithine
cranial morphology. The new taxon possesses a large postorbital with a long
tapering jugal process indicating that some enantiornithines may have had a
fully diapsid skull, as in Confuciusornis. The tooth morphology of the
specimen is unique and likely represents a previously unknown trophic
specialization within Enantiornithes.






Basilici, G., and Führ Dal' Bó, P.F. 2010. Anatomy and controlling factors
of a Late Cretaceous aeolian sand sheet: the Marília and the Adamantina
formations, NW Bauru Basin, Brazil. Sedimentary Geology. doi:
10.1016/j.sedgeo.2010.02.010.

ABSTRACT: Few previous studies have given significant consideration to the
palaeosols in aeolian sand sheet sedimentary successions and, mainly, to
their palaeoenvironmental and stratigraphic meaning in interaction with the
deposits. These themes are considered in this study that deals with the
depositional architecture and the factors controlling the construction,
accumulation and preservation of an ancient aeolian sand sheet, that form
part of the Adamantina and Marília formations, in the Bauru Basin (Late
Cretaceous, Brazil). In the NW portion of the Bauru Basin, these two units,
ca 220 m thick, consist of sandstone, and secondarily of sandy conglomerate
and mudstone, and are characterised by vertically alternated palaeosols and
deposits.
     Facies analyses of the deposits and macroscopic characterisation of the
palaeosols in 45 outcrops were integrated with laboratory analyses that
consisted in descriptions of slabs of rock samples, petrographic analyses,
clay mineralogy determination, geochemical analyses of the major oxides, and
micromorphological characterisation of the palaeosols.
     Three architectural elements were recognised: palaeosols,
wind-ripple-dominated aeolian sand sheet deposits, and ephemeral river
deposits. The palaeosols constitute 66% of the entire sedimentary
succession, and consist principally of Aridisols and, subordinately, of
Alfisols, Vertisols, and Entisols. The wind-ripple-dominated aeolian sand
sheet deposits (25%) are composed of sandstone, organised in translatent
climbing wind-ripple strata, and secondarily of sandstone and mudstone
deposited by infrequent floods. The ephemeral river deposits (9%) consist of
sandy conglomerates 4 m thick and ca 2 km wide. Wind-ripple-dominated
aeolian sand sheet deposits formed during relatively dry climate period on
an unstable topographic surface of a aeolian sand sheet, where aeolian
deposition or erosion prevailed. Palaeosols and ephemeral river deposits
formed in a more humid climate period on a stable topographic surface of the
aeolian sand sheet.
     Six bounding surfaces permitted the subdivision of the study formations
into genetic geological bodies, revealing different spatial and temporal
orders. Two first order surfaces separate mature palaeosol profiles
(Aridisols, Alfisols, and Vertisols) from overlying aeolian deposits or
other mature palaeosol profiles. A second order surface separates immature
palaeosols (Entisols) from overlying aeolian deposits. A third order surface
constitutes the channel bottom. A fourth order surface is located at the
bottom of flood deposits. A fifth order surface divides translatent
wind-ripple.
     The constructional phase of the aeolian sand sheet occurred during the
relatively dry climate period, when the available sediment was supplied from
the material originally deposited by rivers and stored during a more humid
period (primary supply), and by soil erosion during a drier climate
(secondary supply). The accumulation surface was controlled during the drier
climate by cemented Bk horizons over Aridisols and by the force of the wind
blowing over the other soils or deposits. Otherwise, during the more humid
climate, the accumulation surface was a stabilised surface represented by
the soil. Preservation was dominated by tectonically induced subsidence and
burial.






Eaton, J.G. 2009. Cenomanian (Late Cretaceous) mammals from Cedar Canyon,
southwestern Utah, and a revisionn of Cenomanian Alphadon-like marsupials;
pp. 97-110 in Albright, L.B.I. (ed.), Papers on Geology, Vertebrate
Paleontology, and Biostratigraphy in Honor of Michael O. Woodburne. Museum
of Northern Arizona Bulletin 65.

ABSTRACT: Mammals previously reported from the middle member of the Dakota
Formation around the margins of the Paunsaugtmt Plateau, 65-90 km east of
Cedar Canyon, are probably middle or late Cenomanian in age, This is based
on radiometric dates and on stratigraphic proximity to (15-20 m below)
marine deposits of the upper member, which have been dated as late
Cenomanian on the basis of agglutinated foraminifera and ostracodes,
Although the fauna from this region includes two species of marsupials
originally referred to Alphadon, recent revisions of the Alphadontidae
indicate that this referral is no longer valid; thus a new genus,
Eoalphadon, is established for these Alphadon-like taxa, Recently, two new
localities were discovered by "blind-washing" methods in the middle member
of the Dakota Formation in Cedar Canyon, east of Cedar City, more than 100 m
below the upper member. To date, a relatively small amount of matrix (~1
,000 kg) has been processed from these localities, but multituberculate and
therian mammals have been recovered. The multituberculates include
Paracimexomys-like taxa, a new small species of Cedaromys (C. minimus sp.
nov.), Dakotamys malcolmi, and Cimolodontidae and ?Cimolodontidae genus and
species undetermined. The therian fauna includes a spalacotheriid
symmetrodont, a Picopsis-like boreosphenidan, and at least one new species
of Eoalphadon (E. woodburnei gen. et sp. nov.). The presence of Dakotamys
malcolmi, conspecific with a taxon recovered from localities to the east in
the Paunsaugunt region, suggests an approximate age equivalency of the Cedar
Canyon and Paunsaugunt faunas. Eoalphadon woodburnei gen. et sp. nov. is
distinctly more primitive than either E. lillegraveni or E. clemens;
previously described from the Paunsaugunt region, which indicates that the
Cedar Canyon fauna may be slightly older than that from the Paunsaugunt
region, possibly as old as middle or early Cenomanian.





Sweeney, I.J., Chin, K., Hower, J.C., Budd, D.A., and Wolfe, D.G. 2009.
Fossil wood from the middle Cretaceous Moreno Hill Formation: unique
expressions of wood mineralization and implications for the processes of
wood preservation. International Journal of Coal Geology 79(1-2):1-17. doi:
10.1016/j.coal.2009.04.001.

ABSTRACT: The Cretaceous (Turonian) Moreno Hill Formation of west?central
New Mexico provides an opportune isotaphonomic setting to study wood
preservation because both carbonized and mineralized wood are commonly found
within the same sediments and often within individual specimens.
Petrographic, reflectance, maceral, and chemical analyses were used to
compare and characterize mineralized and carbonized wood from the study site
to investigate biases which influence mode of preservation. Coal (in the
form of coal inclusions) is the most common form of fossil wood, and
mineralized wood is also widespread in the formation. Two striking specimens
of in situ coalified stumps are particularly informative because each
includes a mineralized ring that appears to represent the former location of
sapwood. Most of the mineralized samples are primarily composed of quartz,
but a few specimens are predominantly mineralized with apatite. Calcite is
present in charcoal samples where it permineralized, but never replaced
organic carbon. This study points to two key factors that influence
mineralization; wood permeability and the chemical alteration of the wood
prior to incorporation into the sediment. The patterns of mineralization are
consistent with hypothesized microbial involvement in the mineralization
process.
     The coexistence of coal and mineralized tissues in some samples
suggests that the processes of silicification and phosphatization
co-occurred with coalification and that these processes are competitive
within individual pieces of wood. As such, various stages of wood
degradation have been preserved in mineralized samples from the Moreno Hill
Formation. The study suggests that coal inclusions and mineralized wood/coal
associations may also be common in other ancient sediments even though
weathering may obscure their presence. Such information is important for
paleoecological and paleoenvironmental studies which utilize the occurrence
of fossil wood to help reconstruct floral composition or climatic
conditions.





Santucci, V.L., and Kirkland, J.I. 2010. An overview of National Park
Service paleontological resources from the parks and monuments in Utah; pp.
565-599 in Sprinkel, D.A., Chidsey, T.C., Jr., and Anderson, P.B. (eds.),
Geology of Utah's Parks and Monuments (3rd Ed.). Utah Geological Association
Publication 28.  





Lehman, T.M., and Barnes, K. 2010. Champsosaurus (Diapsida: Choristodera)
from the Paleocene of west Texas: paleoclimatic implications. Journal of
Paleontology 84(2):341-345. doi: 10.1666/09-111R.1.

ABSTRACT: A specimen of the aquatic reptile Champsosaurus sp. from the
Paleocene Black Peaks Formation in southwestern Texas is the southernmost
yet known. The fragmentary specimen exhibits some unusual features, such as
a great anterior extent of the quadratojugal on the lower temporal arch, and
cannot be attributed with confidence to any of the named species.
Champsosaurus appears to have been tolerant of temperate climates and had a
northern latitudinal range exceeding that of crocodylians. It seems likely
that the brief southward extension in range of Champsosaurus during early
Paleocene time resulted from a decrease in mean annual temperature,
comparable to over 10° of paleolatitude.






Seneviratne, S.S., and Jones, I.L. 2010. Origin and maintenance of
mechanosensory feather ornaments. Animal Behaviour 79(3):637-644. doi:
10.1016/j.anbehav.2009.12.010.

ABSTRACT: Mechanosensory use is a seldom-mentioned function for feather
ornaments, yet recent experimental evidence showed that the elaborate facial
plumes of crevice-dwelling whiskered auklets, Aethia pygmaea, have just such
a sensory role. Here we explored the evolutionary patterns of mechanosensory
function of similar facial feather ornaments in related species. In an
experimental chamber (maze) devoid of visible light, crested auklets, A.
cristatella, a close relative of the whiskered auklet, showed an increase in
head bumps (262%) after trial flattening of their forehead crest. The
frequency of head bumps in the absence of the crest was positively
correlated with the natural crest length of the crested auklet. There was no
correlation between crest length and head bumps when we added an artificial
crest to least auklets, A. pusilla, which do not have a natural crest. Thus,
only the ornamented Aethia species that breed in deep-crevice appear to have
detectable mechanosensory ability. A pairwise analysis across all
nonpasserine bird families further revealed a greater frequency of elongated
facial plumes in birds that live in complex habitats and are active during
low light conditions. We suggest that selective pressure enforced by complex
habitats may trigger facial feather exaggeration for mechanosensory use.
Once the primordial sensory structures evolved, sexual and other social
selection processes could act on these traits and lead towards further
exaggeration.





Fiorillo, A.R., McCarthy, P.J., and Flaig, P.P. 2010. Taphonomic and
sedimentologic interpretations of the dinosaur-bearing Upper Cretaceous
strata of the Prince Creek Formation, northern Alaska: insights from an
ancient high-latitude terrestrial ecosystem. Palaeogeography,
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2010.02.029.

ABSTRACT: Several dinosaurian bonebeds occur within the
Campanian-Maastrichtian portion of the Prince Creek Formation of northern
Alaska along a 45 km stretch of the Colville River. These beds are
characterized by the occurrence of bones from large numbers of juvenile to
sub-adult dinosaurs entombed in a hydraulically incompatible fine-grained
matrix. The skeletal elements show little evidence for articulation, though
there is evidence for association. Further, the bones show little evidence
of post-mortem alteration such as prolonged exposure to weathering,
predation, or trampling. The sediments of the Late Cretaceous to Paleocene
Prince Creek Formation represent a continental succession deposited on a
high-latitude, low-gradient alluvial/coastal plain. Deposition occurred in
trunk channels, on distributary-channel splay-complexes, in
interdistributary bays, and on floodplains. These bonebeds formed under
unique paleoclimatic and paleogeographic conditions. Although mean annual
temperatures on the coastal plain were higher during the deposition of the
Prince Creek Formation than modern temperatures, the evolving Brooks Range
orogenic belt formed the southern edge of the Colville basin, providing a
high-latitude, cooler alpine environment in close proximity to these warmer
lowland environments. Seasonal flow due to the combination of snow melt and
alpine permafrost in the ancestral Brooks Range likely produced regularly
occurring seasonal floods, which are the likely killing mechanism that
resulted in the formation of these bonebeds.







~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/


"I have noticed even people who
claim everything is predestined, and
that we can do nothing to change it,
look before they cross the road."

                   -- Stephen Hawking

"Prediction is very difficult,
especially of the future."

                   -- Niels Bohr