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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 
theoretical studies.

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 
toxicity today.
     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
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

"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."

                            -- unknown