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10 Ways To Lose New Papers



Hadn't seen these crop up on list yet...thanks to LG, DF, and JN for these!
Also, the new ish of JVP has lots of good stuff, but I haven't had time to
enter them into my db yet...



Loope, D.B. 2008. Life beneath the surfaces of active Jurassic dunes:
burrows from the Entrada Sandstone of south-central Utah. Palaios
23(6):411-419. doi: 10.2110/palo.2006.p06-133r.

ABSTRACT: Within the Middle Jurassic Entrada Sandstone of south-central
Utah, cylindrical burrows, 15?95 mm diameter, are abundant in large-scale,
eolian cross-strata. Burrows are oriented at a high angle to stratification
and commonly extend more than 30 cm below their surface termini. They are
rarely inclined more steeply than 22°. Many are sinuous, and they sometimes
branch (120°) at bends. Burrows terminate upward against flat-topped cones
of structureless sandstone that are up to 15 cm deep and present at
numerous, closely spaced stratigraphic horizons. Entrada eolian dune
deposits also host abundant burrows likely produced by small insects. Both
large and small burrows are most numerous in the uppermost parts of very
thick (up to 35 m) compound sets of cross-strata generated by superimposed
dunes migrating along the lee slopes of giant dune ridges. The size and
morphology of the large burrows and the nature of their fills suggest that
they were excavated by vertebrates, possibly insectivores, but the
possibility that scorpions or spiders dug the burrows cannot be ruled out.
In modern dunes, the top 20 cm of rain-moistened sand dries quickly, but
underlying sediment can remain moist for long periods. Conical pits formed
on the dry surface of Jurassic dunes at the tops of burrows that were
primarily excavated in underlying moist sand. Cones composed of
structureless sandstone are active fills produced when burrowers pushed
moist sand to the surface, forming spoil piles. Most cylindrical portions of
the burrows were also actively backfilled; remaining parts were passively
filled when burrow walls collapsed. Cones at burrow tops now delineate thin
(5?10-cm-thick) packages of cross-strata that record slow (seasonal?) dune
migration. Rainfall on dune surfaces allowed scattered plants, insects, and
insectivorous vertebrates to inhabit the Entrada sand sea. Burrows provided
animals with refuge from the hot, desiccating surface conditions.



Wood, A.R., Kraus, M.J., and Gingerich, P.D. 2008. Downslope fossil
contamination: mammal-bearing fluvial conglomerates and the Paleocene-Eocene
faunal transition (Willwood Formation, Bighorn Basin, Wyoming). Palaios
23(6):380-390. doi: 10.2110/palo.2007.p07-045r.

ABSTRACT: Downslope fossil contamination is the result of erosion and
subsequent redeposition of fossil material onto lower stratigraphic
horizons. This produces time-averaged and potentially anomalous faunal
records. Here, we describe vertebrate concentrations in Bighorn Basin
(Wyoming) conglomerates that are early Wasatchian (earliest Eocene) in age
(Wa-1) and rest erosionally upon Wa-0 strata deposited during the
Paleocene?Eocene thermal maximum (PETM). The Wa-1 conglomerates were
deposited during river channel migration and sheetflooding onto abandoned
parts of an avulsion belt immediately after the PETM. Dark-colored Wa-1
fossil teeth eroding from the conglomerates are now mixed in places with the
lighter-colored teeth of Wa-0 mammals. The spatial distribution of the
conglomerate fossils and a vertical model of downslope contamination, based
on species proportions from overlying stratigraphic intervals, are used to
calculate an expected contribution of fossil contaminants to an assemblage.
Results of this model are applied to address the principal weakness of the
hypothesis that transient decreases in mammalian body size during the PETM
were an evolutionary dwarfing response to climate change. Rare occurrences
of large taxa with congeners of small size would refute the argument for
evolutionary dwarfing, but our results indicate that such rare occurrences
can be explained by downslope contamination alone. We conclude more
generally that alluvial architecture is important for understanding the
potential for downslope fossil contamination and that complications imposed
by this type of contamination can be assessed quantitatively.




Jackson, F.D., Varricchio, D.J., Jackson, R.A., Vila, B., and Chiappe, L.M.
2008. Comparison of water vapor conductance in a titanosaur egg from the
Upper Cretaceous of Argentina and a Megaloolithus siruguei egg from Spain.
Paleobiology 34(2):229-246. doi:
10.1666/0094-8373(2008)034[0229:COWVCI]2.0.CO;2.

ABSTRACT: We calculated water vapor conductance (a product of eggshell
porosity) from the first definitively identified sauropod egg (Megaloolithus
patagonicus) from the Auca Mahuevo locality in Argentina. We then compared
the results with those from M. siruguei (an egg type long associated with
sauropod dinosaurs) from the Pinyes locality in Spain. The 14-cm Auca
Mahuevo egg has a thinner eggshell and 47 times fewer pores than the 22-cm
M. siruguei specimen. The resulting water vapor conductance (GH2O ) of the
titanosaur and M. siruguei eggs is 341 and 3979 mg H2O day-1 Torr-1,
respectively; these values are two and ten times greater than in avian eggs
of comparable size, but lower than in eggs of most modern reptiles. Clutches
from Auca Mahuevo typically contain 20?40 eggs; in contrast, M. siruguei
clutches from the Pinyes site average nine eggs. The GH2O of M. siruguei
exceeds that of the Argentine egg by an order of magnitude, supporting
previous inferences of egg burial. The GH2O of the Argentine titanosaur egg
closely approximates that of Troodon and some oviraptorid eggs, previously
calculated as equal to or two times greater than, respectively, the GH2O of
avian eggs of similar size. Higher embryonic growth rates (relative to
modern reptiles), especially in some dinosaurs with large clutch mass, may
have required incubation in a more open environment, where water
conservation represented a more critical factor than in a buried clutch. The
lower GH2O calculated for the two megaloolithid eggs is consistent with
previous interpretations of nesting mode that are based on site taphonomy
and nesting traces. This study indicates that at least some dinosaurs did
not fully bury their eggs.



Lehman, T.M., and Woodward, H.N. 2008. Modeling growth rates for sauropod
dinosaurs. Paleobiology 34(2):264-281. doi:
10.1666/0094-8373(2008)034[0264:MGRFSD]2.0.CO;2.

ABSTRACT: Sauropod dinosaurs were the largest terrestrial animals and their
growth rates remain a subject of debate. By counting growth lines in
histologic sections and relating bone length to body mass, it has been
estimated that Apatosaurus attained its adult body mass of about 25,000 kg
in as little as 15 years, with a maximum growth rate over 5000 kg/yr. This
rate exceeds that projected for a precocial bird or eutherian mammal of
comparable estimated body mass. An alternative method of estimating limb
length and body mass for each growth line, and fitting the resulting age/
mass data to the von Bertalanffy growth equation, yields a revised growth
curve suggesting that Apatosaurus adult mass was reached by 70 years with a
maximum growth rate of 520 kg/yr. This alternative method for growth rate
determination can also be applied to histological studies of other
sauropods. At only about half the mass of Apatosaurus, Janenschia took
between 20 and 30 years to attain its adult size (over 14,000 kg). This
result is supported by independent evidence of estimated bone apposition
rates. Despite having an adult body mass greater than Apatosaurus, the
titanosaurid Alamosaurus attained a mass over 32,000 kg within 45 years and
a maximum growth rate of 1000 kg/yr. Titanosaurids may have been the fastest
growing of all sauropods. Even so, sauropod growth rate estimates produced
using the von Bertalanffy equation fall between those projected for reptiles
and those for precocial birds of equivalent projected body mass. These
results are comparable to those found for smaller dinosaurs, and suggest
that sauropods grew at rates similar to other dinosaurs in spite of their
great size.



Klein, N., and Sander, M. 2008. Ontogenetic stages in the long bone
histology of sauropod dinosaurs. Paleobiology 34(2):247-263. doi:
10.1666/0094-8373(2008)034[0247:OSITLB]2.0.CO;2.

ABSTRACT: Long bones (femora, humeri) are the most abundant remains of
sauropod dinosaurs. Their length is a good proxy for body length and body
mass, and their histology is informative about ontogenetic age. Here we
provide a comparative assessment of histologic changes in growth series of
several sauropod taxa, including diplodocids (Apatosaurus, Diplodocus,
indeterminate Diplodocinae from the Tendaguru Beds and from the Morrison
Formation), basal macronarians (Camarasaurus, Brachiosaurus, Europasaurus),
and titanosaurs (Phuwiangosaurus, Ampelosaurus). A total of 167 long bones,
mainly humeri and femora, and 18 limb girdle bones were sampled. Sampling
was performed by core drilling at prescribed locations at midshaft, and 13
histologic ontogenetic stages (HOS stages) were recognized. Because growth
of all sauropod long bones is quite uniform, with laminar fibrolamellar bone
being the dominant tissue, HOS stages could be recognized across taxa,
although with minor differences. Histologic ontogenetic stages generally
correlate closely with body size and thus provide a means to resolve
important issue like the ontogenetic status of questionable specimens. We
hypothesize that sexual maturity was attained at HOS-8, well before maximum
size was attained, but we did not find sexually differentiated growth
trajectories subsequent to HOS-8. On the basis of HOS stages, we detected
two morphotypes in the Camarasaurus sample, a small one (type 1) and a
larger one (type 2), presumably representing different species or sexual
dimorphism.



Chen, J., Butler, R.J., and Jin, L. 2008. New material of large-bodied
ornithischian dinosaurs, including an iguanodontian ornithopod, from the
Quantou Formation (middle Cretaceous: Aptian-Cenomanian) of Jilin Province,
northeastern China. Neues Jahrbuch für Geologie und Paläontologie
Abhandlungen 248(3):309-314.

ABSTRACT: The Quantou Formation of Jilin Province, Northeast China, has
recently yielded an important new middle Cretaceous (Aptian?Cenomanian)
fauna of terrestrial vertebrates, including zalambdalestid mammals, basal
ornithopod dinosaurs and basal ceratopsian dinosaurs. Here we describe
well-preserved but isolated and fragmentary material of large-bodied
ornithischian dinosaurs from this formation. An isolated humerus represents
an iguanodontian ornithopod dinosaur, expanding the known stratigraphic and
geographic range of this group within China. Other material (partial distal
tibia, series of three dorsal vertebrae apparently representing part of a
fused synsacrum) can only be assigned to Ornithischia indet.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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