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OK, that's really reaching...but if you have the opportunity to go see "Avatar"
in 3D IMAX, _do it_...it is WELL worth your time...! Onto the new papers:
Cavin, L., Tong, H., Boudad, L., Meister, C., Piuz, A., Tabouelle, J., Aarab,
M., Amiot, R., Buffetaut, E., Dyke, G., Hua, S., and Le Loeuff, J. 2009.
Vertebrate assemblages from the early Late Cretaceous of southeastern Morocco:
an overview. Journal of African Earth Sciences. doi:
10.1016/j.jafrearsci.2009.12.007.
ABSTRACT: Fossils of vertebrates have been found in great abundance in the
continental and marine early Late Cretaceous sediments of Southeastern Morocco
for more than fifty years. About 80 vertebrate taxa have so far been recorded
from this region, many of which were recognised and diagnosed for the first
time based on specimens recovered from these sediments. In this paper, we use
published data together with new field data to present an updated overview of
Moroccan early Late Cretaceous vertebrate assemblages. The Cretaceous series we
have studied encompases three Formations, the Ifezouane and Aoufous Formations,
which are continental and deltaic in origin and are often grouped under the
name “Kem Kem beds”, and the Akrabou Formation which is marine in origin. New
field observations allow us to place four recognised vertebrate clusters,
corresponding to one compound assemblage and three assemblages, within a
general temporal framework. In particular, two ammonite bioevents characterise
the lower part of the Upper Cenomanian (Calycoceras guerangeri Zone) at the
base of the Akrabou Formation and the upper part of the Lower Turonian
(Mammites nodosoides Zone), that may extend into the Middle Turonian within the
Akrabou Formation, and allow for more accurate dating of the marine sequence in
the study area. We are not yet able to distinguish a specific assemblage that
characterises the Ifezouane Formation when compared to the similar Aoufous
Formation, and as a result we regard the oldest of the four vertebrate
“assemblages” in this region to be the compound assemblage of the “Kem Kem
beds”. This well-known vertebrate assemblage comprises a mixture of terrestrial
(and aerial), freshwater and brackish vertebrates. The archosaur component of
this fauna appears to show an intriguingly high proportion of large-bodied
carnivorous taxa, which may indicate a peculiar trophic chain, although
collecting biases alter this palaeontological signal. A small and restricted
assemblage, the OT1 assemblage, possibly corres!
ponds to
he Kem Kem beds compound assemblage. Microfossils and facies from the Aoufous
Formation, corresponding to the top of the compound assemblage, provide
evidence of extremely abiotic conditions (hypersalinity), and thus of great
environmental instability. At the base of the Akrabou Formation the first
ammonite bioevent, Neolobites, corresponds to the onset of the marine
transgression in the early Late Cenomanian while the Agoult assemblage (Late
Cenomanian?) contains a variety of small fish species that have Central Tethyan
affinities. Finally, the youngest Mammites bioevent in the late Early Turonian
corresponds to a deepening of the marine environment: this sequence is
isochronous with the Goulmima assemblage, a diverse collection of fish and
other marine taxa, and shows affinities with taxa from the South Atlantic, the
Central Tethys and the Western Interior seaway of North America, and further
highlights the biogeographical importance of these North African Late
Cretaceous assemblages.
Houssaye, A. 2009. A new aquatic pythonomorph (Reptilia, Squamata) from the
Turonian (Late Cretaceous) of France. Comptes Rendus Palevol. doi:
10.1016/j.crpv.2009.09.002.
ABSTRACT: Disarticulated vertebrae from the Turonian of France display a
distinctive suite of characters and probably represent a new pythonomorph. This
taxon displays some degree of vertebral pachyostosis s.s., often observed in
varanoid squamates from the Cenomanian-Turonian interval of the ‘Mediterranean’
portion of the Tethys. The discovery of this new material highlights the
importance of also describing possibly new taxa based on isolated remains.
Brochu, C.A., Wagner, J.R., Jouve, S., Sumrall, C.D., and Densmore, L.D. 2009.
A correction corrected: consensus over the meaning of Crocodylia and why it
matters. Systematic Biology 58(5):537-543. doi: 10.1093/sysbio/syp053.
I mention this one because it has some interesting implications for possible
life restorations of at least some dinosaurs:
Møller, A.P., and Erritzøe, J. 2009. Why birds eat colourful grit: colour
preferences revealed by the colour of gizzard stones. Journal of Evolutionary
Biology. doi: 10.1111/j.1420-9101.2009.01918.x.
ABSTRACT: Colour preferences from sexual or social contexts are assumed to have
arisen owing to preferences for specific kinds of food, representing a sensory
bias, but once colour preferences have evolved in a sexual context, they may
also be expressed during foraging. We tested whether preferences for specific
body colours (i.e. plumage and soft parts) were related to colour preferences
for grit ingested by birds. Birds eat grit to facilitate break down of food by
the gizzard, and this function is independent of the colour of grit, but
depends on the physical properties of stones. Bird species were significantly
consistent in colour of grit, and grit of different colours varied in
prevalence among species, even when analyses were restricted to a sample from a
single locality. There were positive correlations between presence of lilac and
red grit in the gizzard and presence of sexually dichromatic lilac and red
colour on the body. There was a positive correlation between red grit colour
and red sexually monochromatic body colour. Bird species with many different
sexual colours, but not sexually monochromatic colours on their body had many
different colours of grit. Males had more lilac and red grit than females, with
this effect differing among species, whereas that was not the case for grit of
other colours. These findings are consistent with the sensory bias hypothesis
that birds express preferences for grit of specific colours and a high
diversity of colours related to sexual colouration of the body, even when the
colour of such grit is only visible to the individual at the moment of
ingestion.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/
"The optimist thinks this is the best
of all possible worlds. The pessimist
fears it is true."
-- J. Robert Oppenheimer
"In nuclear war all men are cremated
equal."
-- Dexter Gordon