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The Day The New Papers Stood Still
Apologies if any of these are duplicate listings from anyone else's post.
And let me say it's always great to see list subscribers as authors on
papers -- congrats, Mike!
Habib, M.B., and Ruff, C.B. 2008. The effects of locomotion on the
structural characteristics of avian limb bones. Zoological Journal of the
Linnean Society 153(3):601-624. doi: 10.1111/j.1096-3642.2008.00402.x.
ABSTRACT: Despite the wide range of locomotor adaptations in birds, little
detailed attention has been given to the relationships between the
quantitative structural characteristics of avian limb bones and bird
behaviour. Possible differences in forelimb relative to hindlimb strength
across species have been especially neglected. We generated cross-sectional,
geometric data from peripheral quantitative computed tomography scans of the
humerus and femur of 127 avian skeletons, representing 15 species of extant
birds in 13 families. The sample includes terrestrial runners, arboreal
perchers, hindlimb-propelled divers, forelimb-propelled divers and dynamic
soarers. The hindlimb-propelled diving class includes a recently flightless
island form. Our results demonstrate that locomotor dynamics can be
differentiated in most cases based on cross-sectional properties, and that
structural proportions are often more informative than bone length
proportions for determining behaviour and locomotion. Recently flightless
forms, for example, are more easily distinguished using structural ratios
than using length ratios. A proper phylogenetic context is important for
correctly interpreting structural characteristics, especially for recently
flightless forms. Some of the most extreme adaptations to mechanical loading
are seen in aquatic forms. Penguins have forelimbs adapted to very high
loads. Aquatic species differ from non-aquatic species on the basis of
relative cortical thickness. The combination of bone structural strength and
relative cortical area of the humerus successfully differentiates all of our
locomotor groups. The methods used in this study are highly applicable to
fossil taxa, for which morphology is known but behaviour is not. The use of
bone structural characteristics is particularly useful in palaeontology not
only because it generates strong signals for many locomotor guilds, but also
because analysing such traits does not require knowledge of body mass, which
can be difficult to estimate reliably for fossil taxa.
Arbour, V.M., and Graves, M.C. 2008. An ornithischian dinosaur from the
Sustut Basin, north-central British Columbia, Canada. Canadian Journal of
Earth Sciences 45(4):457-463. doi: 10.1139/E08-009.
ABSTRACT: Dinosaur bones were discovered in 1971 during uranium exploration
in the Sustut Basin, northern British Columbia, Canada. These bones have
more recently been prepared and described and represent an indeterminate
cerapodan dinosaur. Although dinosaur bones have been reported from British
Columbia before now, this specimen represents their earliest recorded
discovery from the province. The bones were collected from loose blocks in a
talus slope, near the intersection of Birdflat Creek and the Sustut River.
They are encased in hard siltstone that shares characteristics with adjacent
outcrops of the Upper Cretaceous Brothers Peak Formation. Bones collected
include the right humerus, right radius, the distal portion of the right
tibia and fibula, two right pedal phalanges, including two unguals, and
several unidentifiable fragments.
Geiser, F. 2008. Ontogeny and phylogeny of endothermy and torpor in mammals
and birds. Comparative Biochemistry and Physiology A 150(2):176-180. doi:
ABSTRACT: Endothermic thermoregulation in small, altricial mammals and birds
develops at about one third to half of adult size. The small size and
consequently high heat loss in these young should result in more pronounced
energetic challenges than in adults. Thus, employing torpor (a controlled
reduction of metabolic rate and body temperature) during development would
allow them to save energy. Although torpor during development in endotherms
is likely to occur in many species, it has been documented in only a few. In
small, altricial birds (4 orders) and marsupials (1 order), which are
poikilothermic at hatching/birth, the development of competent endothermic
thermoregulation during cold exposure appears to be concurrent with the
capability to display torpor (i.e. poikilothermy is followed by
heterothermy), supporting the view that torpor is phylogenetically old and
likely plesiomorphic. In contrast, in small, altricial placental mammals (2
orders), poikilothermy at birth is followed first by a homeothermic phase
after endothermic thermoregulation is established; the ability to employ
torpor develops later (i.e. poikilothermy?homeothermy?heterothermy). This
suggests that in placentals torpor is a derived trait that evolved
secondarily after a homeothermic phase in certain taxa perhaps as a response
to energetic challenges. As mammals and birds arose from different reptilian
lineages, endothermy likely evolved separately in the two classes, and given
that the developmental sequence of torpor differs between marsupials and
placentals, torpor seems to have evolved at least thrice.
Snyder, G.K., and Carello, C.A. 2008. Body mass and the energy efficiency of
locomotion: lessons from incline running. Comparative Biochemistry and
Physiology A 150(2):144-150. doi: 10.1016/j.cbpa.2006.09.026.
ABSTRACT: Rates of oxygen consumption were measured for two bipedal runners
(two species of quail) and two quadrupedal runners (two small species of
rodents), with average body masses that ranged from 0.035 to 0.217 kg,
trained to run on a treadmill set to horizontal and then to a 10° incline.
Rates of oxygen consumption increased linearly with speed for all four
species and the rates of increase were significantly higher (P = 0.05) for
all four species when the animals were run on an incline than when they were
run on a horizontal. The estimated metabolic energy cost to lift 1 kg mass 1
m vertically was similar for bipeds and quadrupeds of similar body mass and
inversely related to body mass for both running styles. When the data for
the animals used in the present study are combined with similar data for
adult animals from the literature, the results show that the metabolic
energy efficiencies of locomotion, estimated from the cost of vertical work,
are the same for bipedal and quadrupedal runners. In both groups, the
metabolic energy efficiency of locomotion is directly related to body mass
for animals smaller than 1 kg body mass.
Zammit, M., Daniels, C.B., and Kear, B.P. 2008. Elasmosaur (Reptilia:
Sauropterygia) neck flexibility: implications for feeding strategies.
Comparative Biochemistry and Physiology A 150(2):124-130. doi:
ABSTRACT: Elasmosaurs were extremely long-necked, aquatic reptiles that used
four flippers for locomotion. Their distinctive long neck distinguishes them
from all other Mesozoic forms, yet the potential uses and constraints of
this structure are poorly understood, particularly with regard to feeding.
Several associated series of elasmosaurian cervical vertebrae were used to
measure ranges of potential flexion. Two-dimensional models, based on a
complete specimen of the Late Cretaceous elasmosaur Aphrosaurus furlongi,
were created to measure mobility in both vertical and horizontal planes.
Accuracy of the models was assessed through comparative analyses with
currently extant vertebrate analogues (e.g. snake, turtle, seal). Results
suggest that the elasmosaurian neck was capable of a 75?177° ventral,
87?155° dorsal, and 94?176° lateral range of movement depending upon the
thickness of cartilage reconstructed between each vertebra. Neck postures
such as a ?swan-like? S-shape are shown to be implausible because they
require > 360° vertical flexion. However, maintenance of a straight neck
while swimming, together with considerable lateral and/or ventral movement
during prey capture and feeding are feasible.
Foreman, B.Z., Rogers, R.R., Deino, A.L., Wirth, K.R., and Thole, J.R. 2008.
Geochemical characterization of bentonite beds in the Two Medicine Formation
(Campanian, Montana), including a new 40Ar/39Ar age. Cretaceous Research
29(3):373-385. doi: 10.1016/j.cretres.2007.07.001.
ABSTRACT: Terrestrial deposits of the Upper Cretaceous (Campanian) Two
Medicine Formation of northwestern Montana preserve multiple bentonite beds
(n = 19) that reflect recurrent pyroclastic events in the Western Interior
Basin. Major and trace element concentrations were determined on 27 samples
derived from four bentonites using X-ray fluorescence spectroscopy. This
study evaluates the potential for geochemically distinguishing three of
these bentonite beds using a stepwise discriminant analysis of trace element
concentrations. Seven elements were found sufficient to establish 100%
classification in the group matrix. The elements (in order of decreasing
contribution to the canonical discriminant functions) are Zr, Sc, V, Cr, U,
Ga, and Th. The validity of these results is strongly supported by
cross-validation methods that correctly assigned 100% of randomly-selected
bentonite samples left out of the stepwise analysis to their correct bed.
These findings indicate geochemical discrimination is a viable tool for
correlation within the formation and suggests its application to more
distant coeval strata. We also report here a new 40Ar/39Ar age of 77.52 ±
0.19 Ma for one of the analyzed bentonite beds. This new radioisotopic age
affords insights into the timing of regional eruptive events, and further
constrains the age of the Two Medicine Formation and its renowned fossil
resources. Finally, the inferred magmatic composition of the original ash
(based on trace element compositions) from the two older bentonites beds
suggest a source in the Elkhorn Mountain Volcanics whereas the younger
bentonites may have been sourced from the Adel Mountain Volcanics.
Mayhew, P.J., Jenkins, G.B., and Benton, T.G. 2008. A long-term association
between global temperature and biodiversity, origination and extinction in
the fossil record. Proceedings of the Royal Society of London B 275:47-53.
ABSTRACT: The past relationship between global temperature and levels of
biological diversity is of increasing concern due to anthropogenic climate
warming. However, no consistent link between these variables has yet been
demonstrated. We analysed the fossil record for the last 520Myr against
estimates of low latitude sea surface temperature for the same period. We
found that global biodiversity (the richness of families and genera) is
related to temperature and has been relatively low during warm ?greenhouse?
phases, while during the same phases extinction and origination rates of
taxonomic lineages have been relatively high. These findings are consistent
for terrestrial and marine environments and are robust to a number of
alternative assumptions and potential biases. Our results provide the first
clear evidence that global climate may explain substantial variation in the
fossil record in a simple and consistent manner. Our findings may have
implications for extinction and biodiversity change under future climate
Codrea, V.A., and Godefroit, P. 2008. New Late Cretaceous dinosaur findings
from northwestern Transylvania (Romania). Comptes Rendus Palevol
7(5):289-295. doi: 10.1016/j.crpv.2008.03.008.
ABSTRACT: In 1905, Nopcsa tentatively identified a fragmentary rib from the
Jibou Formation at Somes Odorhei as belonging to an ornithopod dinosaur.
Therefore, he concluded that the base of this formation is Late Cretaceous,
but this hypothesis was subsequently ignored or rejected by other authors.
New dinosaur bones discovered in this locality by new excavations are here
interpreted as belonging to the euornithopod Zalmoxes shqiperorum
Weishampel, Jianu, Csiki and Norman, 2003. The base of the Jibou Formation
can therefore be regarded as Maastrichtian, correlative to the Sânpetru
Formation and to the middle member of the Densus Ciula Formation from the
Hateg Basin, as well as the base of the Sard Formation in the southwestern
Basin of Transylvania, in the Alba Iulia area. The presence of Zalmoxes at
Somes Odorhei also confirms the northeastern extension for the ?Hateg
Island? in Transylvania.
Sames, B. 2008. Application of Ostracoda and Charophyta from the Late
Jurassic to Early Cretaceous Tendaguru formation at Tendaguru, Tanzania
(East Africa) ? biostratigraphy, palaeobiogeography and palaeoecology.
Palaeogeography, Palaeoclimatology, Palaeoecology 264(3-4). doi:
ABSTRACT: Revisitation of the famous Late Jurassic/Early Cretaceous dinosaur
locality of Tendaguru by a German?Tanzanian expedition in summer 2000
resulted in a new standard section. Micropalaeontologic samples from this
section yielded a marine and nonmarine, partially mixed ostracod fauna
consisting of 40 taxa and some charophyte gyrogonites and utriculi. A few
marine taxa provided biostratigraphic information, although comparable
faunas from the West Indian?Madagascan?East African faunal province are
stratigraphically older (Middle/Late Jurassic), fully marine and strongly
endemic. An (Middle) Oxfordian age is suggested for the lower part of the
Tendaguru formation. Nodosoclavatoroid utriculi (Charophyta) suggest that
the Jurassic/Cretaceous boundary may be located lower in the section than
supposed previously, i.e. in the Trigonia smeei member rather than in the
Upper Saurian member. In biogeographical terms, the marine ostracod fauna is
relatively endemic and has most similarities with that known from eastern
Tanzania. Only a few faunal links to Madagascar, Northwest India and Somalia
exist, and there are no links to South Africa. Ostracods and charophytes
also provided palaeoecological data for specific horizons. In the lower part
of the Middle Saurian member a regression is documented. While the nonmarine
Late Jurassic/Early Cretaceous ostracods of Tendaguru are not applicable to
biostratigraphy so far, they are important because the nonmarine setting is
unique in this area of the Tethys.
Jerry D. Harris
Director of Paleontology
Dixie State College
225 South 700 East
St. George, UT 84770 USA
Phone: (435) 652-7758
Fax: (435) 656-4022
"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