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Law Abiding New Papers
Peters, W.S., and Peters, D.S. 2009. Life history, sexual dimorphism and
'ornamental' feathers in the Mesozoic bird Confuciusornis sanctus. Biology
Letters. doi: 10.1098/rsbl.2009.0574.
ABSTRACT: The life history of Confuciusornis sanctus is controversial.
Recently, the species’ body size spectrum was claimed to contradict
osteohistological evidence for a rapid, bird-like development. Moreover, sexual
size dimorphism was rejected as an explanation for the observed bimodal size
distribution since the presence of elongated rectrices, an assumed ‘male’
trait, was uncorrelated with size. However, this interpretation (i) fails to
explain the size spectrum of C. sanctus which is trimodal rather than bimodal,
(ii) requires implausible neonate masses and (iii) is not supported by analogy
with sexual dimorphisms in modern birds, in which elongated central rectrices
are mostly sex-independent. Available information on C. sanctus is readily
reconciled if we assume a bird-like life history, as well as a pronounced
sexual size dimorphism and sexually isomorphic extravagant feathers as
frequently observed in extant species.
Knoll, F. 2009. On the name Stormbergia dangershoeki Butler. Annales de
Paléontologie. doi: 10.1016/j.annpal.2009.09.001.
ABSTRACT: Imperfection in the formation of the name Stormbergia dangershoeki
Butler is taken as an example so as to warn future taxon authors to repeat it.
Prevosti, F.J., and Chemisquy, M.A. 2009. The impact of missing data on real
morphological phylogenies: influence of the number and distribution of missing
entries. Cladistics. doi: 10.1111/j.1096-0031.2009.00289.x.
ABSTRACT: Here we explore the effect of missing data in phylogenetic analyses
using a large number of real morphological matrices. Different percentages and
patterns of missing entries were added to each matrix, and their influence was
evaluated by comparing the accuracy and error of most parsimonious trees. The
relationships between accuracy and error and different parameters (e.g. the
number of taxa and characters, homoplasy, support) were also evaluated. Our
findings, based on real matrices, agree with the simulation studies, i.e. the
negative effect increases with the percentage of missing entries, and decreases
with the addition of more characters. This indicates that the main problem is
the lack of information, not just the presence of missing data per se. Accuracy
varies with different distribution patterns of missing entries; the worst case
is when missing data are concentrated in a few taxa, while the best is when the
missing entries are restricted to just a few characters. The results expand our
knowledge of the missing data problem, corroborate many of the findings
previously published using simulations, and could be useful for empirical or
Csiki, Z., Grigorescu, D., Codrea, V., and Therrien, F. 2009. Taphonomic modes
in the Maastrichtian continental deposits of the Haţeg Basin, Romania –
palaeoecological and palaeobiological inferences. Palaeogeography,
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2009.10.013.
ABSTRACT: The uppermost Cretaceous continental deposits of the Haţeg Basin (SW
Romania) have yielded a high-diversity vertebrate assemblage, including the
"dwarf" insular dinosaurs of Nopcsa. In 1902, Franz Nopcsa was the first to
comment on the preservation patterns of vertebrate fossils, suggesting that the
most important fossil accumulations, which he simply referred to as
"fossiliferous pockets", were the result of the predatory activity of
crocodilians ("crocodilian feeding grounds"). Recent investigations of the
fossil occurrences within the Haţeg Basin revealed a much wider range of
taphonomic modes, from microfossil bonebeds to isolated, partially- articulated
skeletons, than previously believed. The survey of the vertebrate accumulation
types and their sedimentary context documents a wide range of processes
responsible for their genesis, operating within a fluvial-dominated upland
setting. Study of the individual fossil accumulations yields important
informations on the palaeoecology (composition of local biocenoses, trophic
interactions) and palaeobiology (social behaviour, habitat preferences) of the
Haţeg fossil assemblage.
Castle, J.W., and Rodgers, J.H., Jr. 2009. Hypothesis for the role of
toxin-producing algae in Phanerozoic mass extinctions based on evidence from
the geologic record and modern environments. Environmental Geosciences
16(1):1-23. doi: 10.1306/eg.08110808003.
ABSTRACT: Mass mortalities of invertebrates, fish, birds, and mammals caused by
algal-produced toxins are occurring in modern environments. In addition to
direct effects of these toxins, the large mass of organic material produced by
algal blooms can lead to oxygen depletion during decay, which indirectly causes
death of some biota. Toxin-producing algae occupy a wide range of modern
marine, brackish, and freshwater environments. Their growth is favored by warm
water temperatures, increased inorganic carbon concentrations (e.g., CO2), and
abundant nutrient supplies in aquatic environments. Cyanobacteria (blue-green
algae) are responsible for most of the disease and death caused by algal
Based on characteristics and occurrences of algae in modern aquatic
environments and on observations from the fossil record, we propose that
toxin-producing algae were present in the geologic past and were an important
factor in Phanerozoic mass extinctions. The geologic record demonstrates a
pronounced increase in abundance and environmental range of algae, including
stromatolitic cyanobacterial mats, coincident with major Phanerozoic mass
extinctions. During these past events of algal expansion, population decline of
metazoan taxa could have been caused by effects of algal blooms, including
algal-produced toxins, at a scale sufficient to generate a fossil record of
mass extinction. Environmental changes such as climatic warming, sea level
fluctuation, and increased nutrient supply may have promoted algal blooms over
vast expanses of marine to freshwater environments. From the increasing
frequency of modern, toxin-producing algal blooms, which may be related to
global warming, another massive biotic crisis could be forthcoming.
Parsons, W.L., and Parsons, K.M. 2009. A new ankylosaur (Dinosauria:
Ankylosauria) from the Lower Cretaceous Cloverly Formation of central Montana.
Canadian Journal of Earth Sciences 46(10):721-738. doi: 10.1139/E09-045.
(Sorry -- couldn't grab the abstract for this because CJES is a bit slow
updating their web site, but it introduces the basal ankylosaurid
_Tatankacephalus cooneyorum_ -- "tatanka" is Oglala for "bison.")
Parsons, W.L., and Parsons, K.M. 2009. Further descriptions of the osteology of
Deinonychus antirrhopus (Saurischia, Theropoda). Bulletin of the Buffalo
Society of Natural Sciences 38:43-54.
ABSTRACT: Developmental and/or functional implications are described for
aspects of Deinonychus antirrhopus scapula, pedal, and long bone morphology.
Differences in claw curvature are identified as indicators of juvenile
development, and the presence of periosteal rest lines as evidence for
determinate growth is confirmed. The asymmetric ventral keel morphology that is
characteristic of certain tree-climbing birds is also documented for the
penultimate phalanx of the second pedal digit. The lateral orientation of the
scapula glenoid and the presence of a scapulohumeral ligament would allow the
forelimb an arc of movement that would reach angles extensively above and below
the horizontal plane. Like Archaeopteryx, Deinonychus has a robust
deltopectoral crest anchoring a robust pectoralis muscle. Proximal lateral
flanges are present on the first phalanx of second manual digit. These features
provide additional evidence concerning the behavioral morphology of Deinonychus
and some other members of Dromaeosauridae.
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
"Education is the only thing people
shell out a lot of money for...and
then do everything possible to avoid
getting their money's worth."