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Funny New Papers
Hone, D.W.E., and Rauhut, O.W.M. 2009. Feeding behaviour and bone utilization
by theropod dinosaurs. Lethaia. doi: 10.1111/j.1502-3931.2009.00187.x.
ABSTRACT: Examples of bone exploitation by carnivorous theropod dinosaurs are
relatively rare, representing an apparent waste of both mineral and energetic
resources. A review of the known incidences and possible ecological
implications of theropod bone use concludes that there is currently no
definitive evidence supporting the regular deliberate ingestion of bone by
these predators. However, further investigation is required as the small bones
of juvenile dinosaurs missing from the fossil record may be absent as a result
of theropods preferentially hunting and consuming juveniles. We discuss
implications for both hunting and feeding in theropods based on the existing
data. We conclude that, like modern predators, theropods preferentially hunted
and ate juvenile animals leading to the absence of small, and especially young,
dinosaurs in the fossil record. The traditional view of large theropods hunting
the adults of large or giant dinosaur species is therefore considered unlikely
and such events rare.
Lawing, A.M., and Polly, P.D. 2009. Geometric morphometrics: recent
applications to the study of evolution and development. Journal of Zoology.
doi: 10.1111/j.1469-7998.2009.00620.x.
ABSTRACT: The field of morphometrics is developing quickly and recent advances
allow for geometric techniques to be applied easily to many zoological
problems. This paper briefly introduces geometric morphometric techniques and
then reviews selected areas where those techniques have been applied to
questions of general interest. This paper is relevant to non-specialists
looking for an entry into geometric morphometric methods and for ideas of how
to incorporate them into the study of variation within and between species, the
measurement of developmental stability, the role of development in shaping
evolution and the special problem of measuring the shape of fossil specimens
that are deformed from their original shape.
Klein, N., Scheyer, T., and TÃtken, T. 2009. Skeletochronology and isotopic
analysis of a captive individual of Alligator mississippiensis Daudin, 1802.
Fossil Record 12(2):121-131. doi: 10.1002/mmng.200900002.
ABSTRACT: In the present study, bone histology and isotope composition (C, N,
O) of a femur and three postcranial osteoderms from an approximately 23-25
year-old captive female Alligator mississippiensis Daudin, 1802 were analyzed
to infer the recorded life history. The number of visible annual growth marks
in the femur cross-section is less than the known age for the individual
concerned, this information clearly shows that skeletochronology has certain
limits. However, bone histology reflects very well the traceable life history
of this individual and its slow growth in early ontogeny. Bone histology on the
basis of the osteoderms shows massive remodeling and an only incompletely
preserved growth record, reflecting the egg-laying status of this individual.
Interestingly, the carbon and especially the nitrogen isotope compositions of
the osteoderms differ from those of the femur. This presumably reflects dietary
changes and/or differences in resorption and remodeling processes during tissue
formation of these bones. The N, C, and O isotope composition of the femur is
consistent with the food and water the alligator had ingested during the last
years of its life. Thus, contrary to the osteoderms, the femur yields reliable
data for the reconstruction of an individual's dietary and environmental
history.
Bussert, R., Heinrich, W.-D., and Aberhan, M. 2009. The Tendaguru Formation
(Late Jurassic to Early Cretaceous, southern Tanzania): definition,
palaeoenvironments, and sequence stratigraphy. Fossil Record 12(2):141-174.
doi: 10.1002/mmng.200900004.
ABSTRACT: The well-known Late Jurassic to Early Cretaceous Tendaguru Beds of
southern Tanzania have yielded fossil plant remains, invertebrates and
vertebrates, notably dinosaurs, of exceptional scientific importance. Based on
data of the German-Tanzanian Tendaguru Expedition 2000 and previous studies,
and in accordance with the international stratigraphic guide, we raise the
Tendaguru Beds to formational rank and recognise six members (from bottom to
top): Lower Dinosaur Member, Nerinella Member, Middle Dinosaur Member,
Indotrigonia africana Member, Upper Dinosaur Member, and Rutitrigonia
bornhardti-schwarzi Member. We characterise and discuss each member in detail
in terms of derivation of name, definition of a type section, distribution,
thickness, lithofacies, boundaries, palaeontology, and age. The age of the
whole formation apparently ranges at least from the middle Oxfordian to the
Valanginian through Hauterivian or possibly Aptian. The Tendaguru Formation
constitutes a cyclic sedimentary succession, consisting of three marginal
marine, sandstone-dominated depositional units and three predominantly coastal
to tidal plain, fine-grained depositional units with dinosaur remains. It
represents four third-order sequences, which are composed of transgressive and
highstand systems tracts. Sequence boundaries are represented by transgressive
ravinement surfaces and maximum flooding surfaces. In a more simple way, the
depositional sequences can be subdivided into transgressive and regressive
sequences/systems tracts. Whereas the transgressive systems tracts are mainly
represented by shallow marine shoreface, tidal channel and sand bar sandstones,
the regressive systems tracts predominantly consist of shallow tidal channel,
tidal flat, and marginal lagoonal to supratidal deposits.
Schnyder, J., Dejax, J., Keppens, E., Nguyen Tu Thanh, T., Spagna, P., Slah,
B., Galbrun, B., Riboulleau, A., Tshibangu, J.-P., and Yans, J. 2009. An Early
Cretaceous lacustrine record: organic matter and organic carbon-isotopes at
Bernissart (Mons Basin, Belgium). Palaeogeography, Palaeoclimatology,
Palaeoecology. doi: 10.1016/j.palaeo.2009.07.014.
ABSTRACT: The early Cretaceous Bernissart lake deposits (Mons Basin, Belgium)
constitute an important historical site in the field of palaeontology. In this
study, we focus on the organic matter (OM) content of the 50 m-long borehole
core, âBer 3â, drilled at Bernissart. Organic data (Rock-Eval, palynofacies,
C/N ratios) and carbon isotope measurements on bulk OM and selected, isolated
wood fragments were collected. The OM distribution exhibits two total organic
carbon (TOC) cycles (12 m and 38 m-thick, respectively) that are stacked in a
lower frequency cyclic pattern. A general increase of in situ aquatic
production and preservation of OM through time is evidenced within the
freshwater masses. A spectral analysis of a high-resolution gamma-ray record
demonstrates that the sedimentation was controlled by orbitally-induced
climatic changes. Precession, obliquity and short- and long-term eccentricity
cycles are recognized. The 12 m-thick and the 38 m-thick TOC cycles fit well
with a 100 kyr short term and a 400 kyr long-term eccentricity cycle,
respectively. Long-term organic fluctuations are interpreted as resulting from
orbitally-induced fluctuating lake levels through time. Carbon isotope
evolution of bulk OM is thought to reflect firstly two local patterns of
sedimentation: (1) the changing contribution of in situ amorphous organic
matter versus terrestrial OM, and (2), the possible influence of enhanced
productivity. The negative Î13CWOOD trend recorded at Bernissart seems
equivalent to published coeval Î13CWOOD and Î13CCARB in the Upper Barremian to
Lower Aptian. This trend noted at Bernissart is thus regarded as reflecting
changes of the carbon isotope ratios of atmospheric CO2. Previous presented
palynological data suggest a âmiddleâ Barremian to Lowermost Aptian
stratigraphic range for the succession at Bernissart. According to this new
data-set, we refine the age-assignment for Bernissart: the duration of
deposition is now estimated to range between 0.55 and 2.2 myr in the Upper
Barre!
mian to L
Schwarz-Wings, D., Rees, J., and Lindgren, J. 2009. Lower Cretaceous
mesoeucrocodylians from Scandinavia (Denmark and Sweden). Cretaceous Research.
doi: 10.1016/j.cretres.2009.07.011.
ABSTRACT: The crocodyliform faunas of the lowermost Cretaceous Rabekke and
JydegÃrd Formations on the Baltic island of Bornholm, Denmark, and the Annero
Formation of SkÃne, southernmost Sweden, are represented by isolated teeth,
osteoderms, and vertebrae. The rich Berriasian assemblage of the Rabekke
Formation includes at least three distinctive taxa: Bernissartia sp.,
Theriosuchus sp., and Goniopholis sp., an association that is also known from
several other contemporaneous European vertebrate localities. In contrast to
this fauna, the JydegÃrd and Annero formations have yielded only rare
mesoeucrocodylian remains, which are assigned to Theriosuchus sp. and an
undetermined mesoeucrocodylians taxon, possibly Pholidosaurus. Geographically,
the Scandinavian localities represent the easternmost and northernmost
distribution of typical continental Jurassic-Cretaceous crocodyliform
communities in Europe.
LÃ, J., Azuma, Y., Dong, Z., Barsbold, R., Kobayashi, Y., and Lee, Y.-N. 2009.
New material of dsungaripterid pterosaurs (Pterosauria: Pterodactyloidea) from
western Mongolia and its palaeoecological implications. Geological Magazine
146(5):690-700. doi: 10.1017/S0016756809006414.
ABSTRACT: New material of dsungaripterid pterosaurs from the Early Cretaceous
of Tatal, western Mongolia, allows the diagnoses of Dsungaripteridae and
Noripterus to be amended. All pterosaurs found at Tatal belong to
Dsungaripteridae (either Dsungaripterus or Noripterus). The name Phobetor is a
junior synonym of Noripterus. The differing shapes of the anterior tips of
skulls, differing tooth morphologies and the coexistence of both Dsungaripterus
and Noripterus may imply that they occupied distinct ecological niches.
Cope, J.C.W. 2009. Correlation problems in the Kimmeridge Clay Formation (Upper
Jurassic, UK): lithostratigraphy versus biostratigraphy and chronostratigraphy.
Geological Magazine 146(2):266-275. doi: 10.1017/S0016756808005852.
ABSTRACT: A scheme of grouped lithostratigraphical units (âbedsâ) proposed for
the English Upper Jurassic Kimmeridge Clay Formation has been claimed to be
also chronostratigraphical, but some of the resulting time-correlations
conflict with those of the standard chronozonation based on ammonite
biostratigraphy. Review of some critical ammonite species reaffirms the
validity of the ammonite zonal scheme and shows that mismatching of lithologies
(facies-correlations) has led to incorrect time-correlations. Because the
numbering scheme of âbedsâ was based on correlations of attenuated successions,
it is on too coarse a time-scale to identify many non-sequences, and its
usefulness as a chronostratigraphical tool is questioned. Evidence suggests
that at least some calcareous concretions in the Kimmeridge Clay formed at
shallow depths, which is relevant to discussions of the succession in terms of
basin analysis.
Dalla Vecchia, F.M. 2009. Anatomy and systematics of the pterosaur
Carniadactylus gen. n. rosenfeldi (Dalla Vecchia, 1995). Rivista Italiana di
Paleontologia e Stratigrafia 115(2):159-188.
ABSTRACT: The holotype specimen of the non-pterodactyloid pterosaur
Eudimorphodon rosenfeldi from the Late Triassic (Norian) of NE Italy is
described in detail and compared to the other specimens referred in literature
to the genus Eudimorphodon. It is considered conspecific with the specimen MPUM
6009 from the Norian of NW Italy, previously attributed to Eudimorphodon
ranzii. A new genus, Carniadactylus, is proposed for the two specimens based on
the apomorphic shape of the âcoronoidâ process, coracoid and pteroid, wing
phalanx proportions and the several anatomical differences with E. ranzii and
âEudimorphodonâ cromptonellus. No definitive evidence of a juvenile stage
occurs in the two specimens. A phylogenetic analysis using parsimony shows that
Carniadactylus is nested inside the Campylognathoididae and is the sister-group
of Caviramus schesaplanensis + âRaeticodactylusâ filisurensis. The systematics
of specimens referred in the literature to Eudimorphodon is reviewed.
Vila, B., Galobart, A., Oms, O., Poza, B., and Bravo, A.M. 2009. Assessing the
nesting strategies of Late Cretaceous titanosaurs: 3-D clutch geometry from a
new megaloolithid eggsite. Lethaia. doi: 10.1111/j.1502-3931.2009.00183.x
ABSTRACT: Detailed mapping and excavation at the egg locality of Font del
Bullidor (Vallcebre Syncline, NE Iberian Peninsula) document various clutches
with megaloolithid (Megaloolithus siruguei) eggs and provide significant
information on the mode of incubation of Late Cretaceous titanosaurs. Clutches
of eggs are preserved in a greyish lagoonal mudstone deposited overlying a
sinuous channel infill. Despite the lithological uniformity of the mudstone,
clutch architecture can be inferred from the topographical position of the eggs
within some clutches. Mapping methods underscore the importance of documenting
the spatial relationship of the egg-bearing bed and the mapping plan, as well
as an accurate 3-D coordinate acquisition. Both geometry of the clutches and
taphonomic observations on particular eggs indicate that eggs were laid in a
shallow pit excavated into the substrate. Most of the eggs were incubated under
a cover of sediment before hatching or cracking. This corroborates previous
inferences on nesting mode.
Desojo, J.B., and Vizcaino, S.F. 2009. Jaw biomechanics of the South American
aetosaur Neoaetosauroides engaeus. Palaontologische Zeitschrift. doi:
10.1007/s12542-009-0032-6.
ABSTRACT: The function of the jaw apparatus and the possible dietary habits of
the aetosaur Neoaetosauroides engaeus from the Triassic of South America were
analyzed in comparison with Northern Hemisphere aetosaurs Desmatosuchus
haplocerus and Stagonolepis robertsoni and the living short-snouted crocodile
Alligator mississippiensis. The adductor and depressor jaw musculature of these
was reconstructed on the basis of dental and skeletal comparisons with living
closest relativesâ extant phylogenetic bracket (EPB), followed by the analysis
of the moment arms of these muscles to infer feeding habits. The aetosaurian
skull design indicates that the total leverage of the inferred jaw musculature
provides force rather than speed. However, within aetosaurs, the high ratios of
muscle moment arms to bite moments indicate stronger bites in the northern
Hemisphere forms, and faster ones in Neoaetosauroides. These differences
indicate more developed crushing, chopping, and slicing capacities, especially
at the back of the tooth series for D. haplocerus and S. robertsoni; whereas it
opens a window to consider different abilities in which speed is involved for
N. engaeus. There are differences among aetosaurs in dental characteristics,
position of the supratemporal fenestra, location of the jaw joint relative to
the tooth row, and shape of the lower jaw. Neoaetosauroides does not show
evidence of dental serrations and wear facets, probably consistent with a
relatively soft and non-abrasive diet, for example soft leaves and/or larvae
and insects without hard structures. It might be possible that Neoaetosauroides
represents a tendency towards insectivorous feeding habits, exploiting a food
source that was widespread in continental environments throughout the Triassic.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/
"Experience is what you get when
you didn't get what you wanted."
-- unknown