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Dead Men Don't Wear New Papers

First, a bunch o' new things for the footprint fans in the crowd:

Stanford, R., Lockley, M., and Weems, R. 2007. Diverse dinosaur-dominated
ichnofaunas from the Potomac Group (Lower Cretaceous) Maryland. Ichnos
14(3-4):155-173. doi: 10.1080/10420940601049404.

ABSTRACT: Until recently fossil footprints were virtually unknown from the
Cretaceous of the eastern United States. The discovery of about 300
footprints in iron-rich siliciclastic facies of the Patuxent Formation
(Potomac Group) of Aptian age is undoubtedly one of the most significant
Early Cretaceous track discoveries since the Paluxy track discoveries in
Texas in the 1930s. The Patuxent tracks include theropod, sauropod,
ankylosaur and ornithopod dinosaur footprints, pterosaur tracks, and
miscellaneous mammal and other vertebrate ichnites that collectively suggest
a diversity of about 14 morphotypes. This is about twice the previous
maximum estimate for any known Early Cretaceous vertebrate ichnofauna. Among
the more distinctive forms are excellent examples of hypsilophodontid tracks
and a surprisingly large mammal footprint. A remarkable feature of the
Patuxent track assemblage is the high proportion of small tracks indicative
of hatchlings, independently verified by the discovery of a hatchling-sized
dinosaur. Such evidence suggests the proximity of nest sites. The
preservation of such small tracks is very rare in the Cretaceous track
record, and indeed throughout most of the Mesozoic.
This unusual preservation not only provides us with a window into a diverse
Early Cretaceous ecosystem, but it also suggests the potential of such
facies to provide ichnological bonanzas. A remarkable feature of the
assemblage is that it consists largely of reworked nodules and clasts that
may have previously been reworked within the Patuxent Formation. Such
unusual contexts of preservation should provide intriguing research
opportunities for sedimentologists interested in the diagenesis and
taphonomy of a unique track-bearing facies.

Astibia, H., Pereda Suberbiola, X., Payros, A., Murelaga, X., Berreteaga, A., Ignacio Baceta, J., and Badiola, A. 2007. Bird and mammal footprints from the Tertiary of Navarre (western Pyrenees). Ichnos 14(3-4):175-184. doi: 10.1080/10420940601049917.

ABSTRACT: A rich variety of vertebrate footprints is known from a number of
Upper Eocene to Lower Miocene localities of Navarre (western Pyrenees). The
sediments were deposited in a wide range of depositional environments, from
marginal marine to diversified terrestrial. Abundant bird tracks have been
found in the coastal deposits of the Upper Eocene Liedena Sandstone of the
Yesa and Itzagaondoa areas. Ciconiiformes-like (Leptoptilostipus pyrenaicus)
and Charadriiformes-like (Charadriipeda ichnospp.) footprints have been
recognized. Mammal ichnites have been discovered in the Oligocene and Lower
Miocene deposits of Navarre. Equoid perissodactyl ichnites similar to those
of Plagiolophustipus occur in the Oligocene fluviatile rocks of the Mués
Sandstone of Olexoa and the Rocaforte Sandstone near Oibar and Sada.
Trackways of entelodontids (Entelodontipus) are known in
fluviatile-palustrine beds of the Oligocene Mués Sandstone of Olkotz.
Additionally, bird (Charadriiformes-like) tracks are known in
fluviatile-palustrine floodplain deposits of the Lower Miocene Ujué
Formation of Los Arcos. In the same area, the Desoio and Los Arcos outcrops
have also yielded perissodactyl trackways of possible Equoidea. Trackways of
rhinocerotids (?) and artiodactyls (possibly Pecoripeda) are described from
the Lower Miocene (Ramblian) palustrine limestones marginal to the Lerín
Formation of Kaparroso and from alluvial fan deposits of the
Uncastillo-Perdón Formation of Altzorritz, respectively.

D'Orazi Porchetti, S., and Nicosia, U. 2007. Re-examination of some large Early Mesozoic tetrapod footprints from the African collection of Paul Ellenberger. Ichnos 14(3-4):219-245. doi: 10.1080/10420940601049990.

ABSTRACT: The Late Triassic - Early Jurassic ichnofauna described mainly by
Paul Ellenberger from southern Africa (Lesotho) is a valuable window on
first phases of dinosaur diversification. Unfortunately, the present
taxonomic status of several forms from that ichnofauna is unclear. The
revision of this material has been frequently invoked and partially done
without reaching many definitive results. Due to the enormous amount of
data, a global revision seems at present impossible and must be accomplished
in smaller steps. A small number of Ellenberger's ichnogenera including
Tetrasauropus, Pseudotetrasauropus, Pentasauropus, Paratetrasauropus,
Sauropodopus and Deuterosauropodopus, which different authors have ascribed
to basal sauropodomorphs, are here revised in a consistent manner and their
attribution to osteological clades is considered. Tetrasauropus and
Pseudotetrasauropus are here validated as the only ichnotaxa related to
sauropodomorphs. Pentasauropus is retained as valid, and a therapsid
trackmaker is suggested. Paratetrasauropus and Sauropodopus are also
validated and ascribed to non-dinosaurian trackmakers, and
Deuterosauropodopus is synonymized with Sauropodopus.

Lockley, M.G., Lires, J., García-Ramos, J.C., Pinuela, L., and Avanzini, M.
2007. Shrinking the world's largest dinosaur tracks: observations on the
ichnotaxonomy of Gigantosauropus asturiensis and Hispanosauropus hauboldi
from the Upper Jurassic of Asturias, Spain. Ichnos 14(3-4):247-255. doi:

ABSTRACT: The type material of the ichnospecies Gigantosauropus asturiensis
Mensink and Mertmann 1984 is re-examined and shown to represent a sauropod
rather than a theropod. This interpretation confirms the recent suggestions
of several authors. We describe the trackway in detail but conclude that it
is not diagnostic at any taxonomic level, below the general category of
sauropod. Thus, G. asturiensis may legitimately be considered a nomen
dubium, and the name should be restricted to the original material and not
extended to formally describe other poorly preserved specimens. Claims that
the largest pes tracks are 1.35 or even 1.5 m in length are incorrect. Pes
length ranges from 98-125 cm (mean 110.75 cm).
Hispanosauropus hauboldi Mensink and Mertmann 1984 is also of doubtful
utility as previously defined. The holotype, a field specimen, which clearly
represents a theropod dinosaur, cannot be located, and may be lost to
erosion. The paratype is a sauropod track and therefore has no relevance to
the ichno-species description. Therefore, we select a new paralectotype and
provide a more detailed description of specimens that can be assigned to
this ichnotaxon. Hispanosauropus is similar to tracks recently described
under the label Megalosauripus. However, the status of this latter
ichnogenus, and the spectrum of track types to which it refers, is disputed.
Thus, we provisionally restrict the name Hispanosauropus to the original
illustrated holotype and a paralectotype from the same locality. On the
grounds of morphological similarity, the name may be applied to similar
material from elsewhere in the Upper Jurassic of Asturias.

Romano, M., Whyte, M.A., and Jackson, S.J. 2007. Trackway ratio: a new look at trackway gauge in the analysis of quadrupedal dinosaur trackways and its implications for ichnotaxonomy. Ichnos 14(3-4):257-270. doi: 10.1080/10420940601050014.

ABSTRACT: A new parameter, the Trackway Ratio (TR), is proposed to
supplement the previously used trackway gauge to describe and quantify the
relative width of trackways in dinosaur quadrupedal gaits. It is expressed
as the ratio of the width of the tracks relative to the total width of the
trackway (both measured perpendicular to the long axis of the trackway). The
ratio may be used with either pes (PTR) or manus (MTR) tracks. The PTR range
of values for wide-, medium- and narrow-gauge trackways of previous authors
are provisionally suggested to be <=35%, 36-49% and >=50%, respectively. The
application of such a ratio would permit a more consistent ichnotaxonomy to
be adopted where both track morphology and trackway parameters are used to
define ichnotaxa.
Determination of the TR, as well as other parameters, will be affected by
track preservation quality. Recent experiments on track simulation in the
laboratory have shed further light on observations made in the field
concerning the value of track measurements (in particular track length and
width) recorded from below the surface on which the maker was moving.
Experimental track simulations in the laboratory have shown that the
dimensions of transmitted tracks preserved below the surface on which the
foot was impressed may vary from 65% to 135% of the true dimensions of the
indenter. Two case studies are presented that quantify the errors that may
be made on calculating TR and the size, gait and speed of the maker, from
trackways if the preservation of the tracks are not fully understood.
It is shown that in individual trackways the PTR may vary along the length
of the trackway; so that part of the trackway may be classified as
wide-gauge and other parts medium-gauge. There is a relationship between
variation in PTR and that of pace angulation along the length of a single
trackway. An analysis of 42 trackways, principally sauropod, shows a
temporal distribution that does not agree closely with previous suggestions
relating to narrow- and wide-gauge trackways.

Weems, R.E., Culp, M.J., and Wings, O. 2007. Evidence for prosauropod
dinosaur gastroliths in the Bull Run Formation (Upper Triassic, Norian) of
Virginia. Ichnos 14(3-4):271-295. doi: 10.1080/10420940601050030.

ABSTRACT: Definitive criteria for distinguishing gastroliths from
sedimentary clasts are lacking for many depositional settings, and many
reported occurrences of gastroliths either cannot be verified or have been
refuted. We discuss four occurrences of gastrolith-like stones (category 6
exoliths) not found within skeletal remains from the Upper Triassic Bull Run
Formation of northern Virginia, USA. Despite their lack of obvious skeletal
association, the most parsimonious explanation for several characteristics
of these stones is their prolonged residence in the gastric mills of large
animals. These characteristics include 1) typical gastrolith microscopic
surface texture, 2) evidence of pervasive surface wear on many of these
stones that has secondarily removed variable amounts of thick weathering
rinds typically found on these stones, and 3) a width/length-ratio modal
peak for these stones that is more strongly developed than in any population
of fluvial or fanglomerate stones of any age found in this region. When
taken together, these properties of the stones can be explained most
parsimoniously by animal ingestion and gastric-mill abrasion. The size of
these stones indicates the animals that swallowed them were large, and the
best candidate is a prosauropod dinosaur, possibly an ancestor of the Early
Jurassic gastrolith-producing prosauropod Massospondylus or Ammosaurus.
Skeletal evidence for Upper Triassic prosauropods is lacking in the Newark
Supergroup basins; footprints (Agrestipus hottoni and Eubrontes isp.) from
the Bull Run Formation in the Culpeper basin previously ascribed to
prosauropods are now known to be underprints (Brachychirotherium parvum) of
an aetosaur and underprints (Kayentapus minor) of a ceratosaur. The absence
of prosauropod skeletal remains or footprints in all but the uppermost
(upper Rhaetian) Triassic rocks of the Newark Supergroup is puzzling because
prosauropod remains are abundant elsewhere in the world in Upper Triassic
(Carnian, Norian, and lower Rhaetian) continental strata. The apparent
scarcity of prosauropods in Upper Triassic strata of the Newark Supergroup
is interpreted as an artifact of ecological partitioning, created by the
habitat range and dietary preferences of phytosaurs and by the
preservational biases at that time within the lithofacies of the Newark
Supergroup basins.

Then, for the bird flight fanatics:

Askew, G.N., and Ellerby, D.J. 2007. The mechanical power requirements of
avian flight. Biology Letters. doi: 10.1098/rsbl.2007.0182.

ABSTRACT: A major goal of flight research has been to establish the
relationship between the mechanical power requirements of flight and flight
speed. This relationship is central to our understanding of the ecology and
evolution of bird flight behaviour. Current approaches to determining flight
power have relied on a variety of indirect measurements and led to a
controversy over the shape of the power-speed relationship and a lack of
quantitative agreement between the different techniques. We have used a new
approach to determine flight power at a range of speeds based on the
performance of the pectoralis muscles. As such, our measurements provide a
unique dataset for comparison with other methods. Here we show that in
budgerigars (Melopsittacus undulatus) and zebra finches (Taenopygia guttata)
power is modulated with flight speed, resulting in U-shaped power-speed
relationship. Our measured muscle powers agreed well with a range of powers
predicted using an aerodynamic model. Assessing the accuracy of mechanical
power calculated using such models is essential as they are the basis for
determining flight efficiency when compared to measurements of flight
metabolic rate and for predicting minimum power and maximum range speeds,
key determinants of optimal flight behaviour in the field.

A non-avian dinosaur paper:

Ji, S., Gao, C., Liu, J., Meng, Q., and Ji, Q. 2007. New material of
Sinosauropteryx (Theropoda: Compsognathidae) from western Liaoning, China.
Acta Geologica Sinica (English Edition) 81(2):177-182.

ABSTRACT: An incomplete specimen of Sinosauropteryx prima collected from the
Early Cretaceous Yixian Formation of the Dawangzhangzi area in Lingyuan,
western Liaoning is depicted. It represents the first systematically
described material of this feathered compsognathid outside the Sihetun area
in Beipiao. This specimen shows some diagnostic features of Sinosauropteryx
prima, such as the very short forelimb in relation to hindlimb with the
length ratio of humerus plus radius to femur plus tibia just around 30%, and
the long and massive first manual ungual subequal in length to radius. The
presence of Sinosauropteryx prima only at Sihetun and Dawangzhangzi supports
the suggestion that the fossil-bearing beds in the Sihetun and Dawangzhangzi
areas are equivalent to each other within the Yixian Formation.

...and a Mesozoic mammal paper:

Rougier, G.W., Martinelli, A.G., Forasiepi, A.M., and Novacek, M.J. 2007.
New Jurassic mammals from Patagonia, Argentina: a reappraisal of
australosphenidan morphology and interrelationships. American Museum
Novitates 3566:1-54. doi: 10.1206/0003-0082(2007)507[1:NJMFPA]2.0.CO;2.

ABSTRACT: A new mammal, Henosferus molus, n.gen. and n.sp., from the
Callovian-Oxfordian (latest Middle to earliest Late Jurassic) Cañadón
Asfalto Formation from Chubut Province (Argentina) is described. This taxon
corresponds to a new species clearly different from Asfaltomylos patagonicus
from the same locality and stratigraphic level. This new species is based on
three lower jaws with relatively well-preserved dentition. The lower jaw
shows a primitive morphology having a Meckelian groove, a prominent medial
flange associated with a lateral ridge of the dentary, and a deep dentary
trough, which possibly indicates the presence, even though reduced, of
postdentary bones still attached to the dentary. The lower dental formula is
i4, c1, p5, m3. The premolars are simple, bearing a main cusp, while the
molars appear to be tribosphenic, with an obtuse to right-angled trigonid
and a basined talonid with three cusps. This association of plesiomorphic
features in the jaw and derived features in the molars is documented in
several taxa of the recently proposed Australosphenida. A phylogenetic
analysis of mammaliaforms nests the new species with Asfaltomylos from the
same locality and stratigraphic level; Henosferidae, new family, is
recognized for Asfaltomylos and Henosferus, representing the basal radiation
of Australosphenida. Henosferidae is the sister group to Ambondro from the
Middle Jurassic of Madagascar, which, in agreement with previous
phylogenies, is the sister taxon to the remaining australosphenidans.
Additionally, our phylogenetic analysis does not support the inclusion of
australosphenidans within eutherians. Henosferids likely retained some
connection of the postdentary elements with the dentary; therefore, if the
inclusion of Monotremata within Australosphenida is confirmed, final freeing
of the postdentary elements and development of a tri-ossicular middle ear
would be convergent events in Monotremata and Theria. Finally, the
distinctiveness of the yet sparse South American record of Jurassic mammals
when compared with the slightly better documented Cretaceous data is
emphasized. The clear faunistic break between the Middle Jurassic and
Early/Late Cretaceous underlies our rudimentary understanding of the
evolution of Mesozoic mammals in Gondwana.

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

"Trying to estimate the divergence times
of fungal, algal or prokaryotic groups on
the basis of a partial reptilian fossil and
protein sequences from mice and humans
is like trying to decipher Demotic Egyptian with
the help of an odometer and the Oxford
English Dictionary."
              -- D. Graur & W. Martin (_Trends
                  in Genetics_ 20[2], 2004)