[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

When New Met Papers



Already some with 2008 dates on them...!  First, I know I posted this one
already, but without the abstract, so here's a more complete citation (yes,
the typo in the title belongs there):


Zheng, X., Zhang, Z., and Hou, L. 2007. A new enantiornitine bird with four
long rectrices from the Early Cretaceous of northern Hebei, CHina. Acta
Geologica Sinica (English Edition) 81(5):703-708.

ABSTRACT: Paraprotopteryx gracilis, a new enantiornithine bird from the
Early Cretaceous Yixian Formation in Fengning, northern Hebei Province is
erected, based on the following characters: Y-shaped furcula with a long
hypocleidum and a much narrow interclavicular angle, and the morphology of
the sternum are different from other enantiornithines. Additionally, alular
digit bearing the biggest manual claw extends distally to the distal end of
the major metacarpal; the minor metacarpal is slender than the major
metacarpal. Carpometacarpus only fused proximally; astragalus and calcaneum
partially fused to one another but unfused to the tibia. This is the first
record of Mesozoic birds in having four long rectrices, which may represent
morphologically a secondary sexual character, an intermediate stage from
elongated scale to branched feather, and possess functional advantage in
supplementing the lifting surface to compensate the unskilled flight.


Then:


Gillette, D.D. 2007. Mystery of the sickle-claw dinosaur. Plateau 4(2):9-69.

     (On _Nothronychus_ -- the article is an accompaniment to the current
exhibit on the thing at the Museum of Northern Arizona -- very, very nice
exhibit!  _Plateau_ is the magazine for the members of the MNA.)




Pemberton, S.G., McCrea, R., Gingras, M.K., Sarjeant, W.A.S., and
MacEachern, J.A. 2008. History of ichnology: the correspondence between the
Reverend Henry Duncan and the Reverend William Buckland and the discovery of
the first vertebrate footprints. Ichnos 15(1):5-17. doi:
10.1080/10420940600864670.

ABSTRACT: The Reverend Henry Duncan (1774-1846), clergyman, philosopher,
writer, politician, archeologist, poet, educator, social reformer, and the
founder of savings banks, was indeed a Man for All Seasons. In 1824, while
Minister of the Church of Scotland at Ruthwell, Dumfriesshire, he was
presented with a slab of red sandstone from the Corncockle Muir quarry in
Annandale, exhibiting a set of footprints on it. Although Duncan felt from
the start that he was dealing with the tracks of an animal, he wrote to the
Reverend William Buckland, Reader in Mineralogy and Geology at the
University of Oxford, to solicit his opinion on the origin of these curious
markings. Buckland was at first skeptical, but after receiving casts of the
markings from Duncan, he became convinced that they did in fact represent
footprints. Duncan and Buckland maintained a correspondence about the
footprints, and on January 7, 1828, Duncan described the Corncockle Muir
footprints to the Royal Society of Edinburgh and quoted Buckland's findings.
Duncan's paper was not published by the Society until 1831, but it aroused
considerable interest - "Footsteps before the Flood"! - and was reported in
several newspapers. This was the first scientific report of a fossil track;
although a schoolboy, Pliny Moody, had found fossil footprints in
Connecticut in 1802, they were not scientifically described until 1836. The
Scottish tracks are now considered to be not reptilian but of synapsid
origin and the rocks containing them are now known to be of Permian age.



Milàn, J., and Bromley, R.G. 2008. The impact of sediment consistency on
track and undertrack morphology: experiments with emuy tracks in layered
cement. Ichnos 15(1):18-24. doi: 10.1080/10420940600864670.

ABSTRACT: To demonstrate the influence of sediment consistency on track and
undertrack morphology, an emu foot was impressed in four packages of
layered, colored cement. The packages contained different ratios of cement
to water and were subsequently sliced vertically to reveal the subsurface
deformation caused by the foot, and to expose the differences in track and
undertrack morphology at different degrees of firmness. A further package of
alternating layers of sand and cement layers was prepared, allowing the
package to be spilt along horizontal surfaces in order to investigate the
undertrack formation and loss of information with depth. The experiments
clearly show that increasing water content in the sediment has a strong
effect on the morphology of both the true track and the undertracks.





Fletcher, B.J., Brentnall, S.J., Anderson, C.W., Berner, R.A., and Beerling,
D.J. 2008. Atmospheric carbon dioxide linked with Mesozoic and early
Cenozoic climate change. Nature Geoscience 1:43-48. doi:
10.1038/ngeo.2007.29.

ABSTRACT: The relationship between atmospheric carbon dioxide (CO2) and
climate in the Quaternary period has been extensively investigated, but the
role of CO2 in temperature changes during the rest of Earth's history is
less clear. The range of geological evidence for cool periods during the
high CO2 Mesozoic 'greenhouse world' of high atmospheric CO2 concentrations,
indicated by models and fossil soils, has been particularly difficult to
interpret. Here, we present high-resolution records of Mesozoic and early
Cenozoic atmospheric CO2 concentrations from a combination of carbon-isotope
analyses of non-vascular plant (bryophyte) fossils and theoretical
modelling. These records indicate that atmospheric CO2 rose from 420
p.p.m.v. in the Triassic period (about 200 million years ago) to a peak of
1,130 p.p.m.v. in the Middle Cretaceous (about 100 million years ago).
Atmospheric CO2 levels then declined to 680 p.p.m.v. by 60 million years
ago. Time-series comparisons show that these variations coincide with large
Mesozoic climate shifts, in contrast to earlier suggestions of climate?CO2
decoupling during this interval. These reconstructed atmospheric CO2
concentrations drop below the simulated threshold for the initiation of
glaciations on several occasions and therefore help explain the occurrence
of cold intervals in a 'greenhouse world'.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/

"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