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Antarctic Cretaceous-Paleocene climate (free pdf) + other non-dino papers, news

From: Ben Creisler

Here is a selection of recent papers and news stories not strictly
related to dinosaurs:

David B. Kemp, Stuart A. Robinson, J. Alistair Crame, Jane E. Francis,
Jon Ineson, Rowan J. Whittle, Vanessa Bowman, and Charlotte O'Brien
A cool temperate climate on the Antarctic Peninsula through the latest
Cretaceous to early Paleogene.
Geology (advance online publication)
doi: 10.1130/G35512.1

[pdf is free]

Constraining past fluctuations in global temperatures is central to
our understanding of the Earth's climatic evolution. Marine proxies
dominate records of past temperature reconstructions, whereas our
understanding of continental climate is relatively poor, particularly
in high-latitude areas such as Antarctica. The recently developed
MBT/CBT (methylation index of branched tetraethers/cyclization ratio
of branched tetraethers) paleothermometer offers an opportunity to
quantify ancient continental climates at temporal resolutions
typically not afforded by terrestrial macrofloral proxies. Here, we
have extended the application of the MBT/CBT proxy into the Cretaceous
by presenting paleotemperatures through an expanded sedimentary
succession from Seymour Island, Antarctica, spanning the latest
Maastrichtian and Paleocene. Our data indicate the existence of a
relatively stable, persistently cool temperate climate on the
Antarctic Peninsula across the Cretaceous-Paleogene boundary. These
new data help elucidate the climatic evolution of Antarctica across
one of the Earth's most pronounced biotic reorganizations at the
Cretaceous-Paleogene boundary, prior to major ice-sheet development in
the late Paleogene. Our work emphasizes the likely existence of
temporal and/or spatial heterogeneities in climate of the southern
high latitudes during the early Paleogene.


Digital reconstructions of fossils

John A. Cunningham, Imran A. Rahman, Stephan Lautenschlager, Emily J.
Rayfield & Philip C.J. Donoghue (2014)
A virtual world of paleontology.
Trends in Ecology and Evolution 29(6): 347–357
DOI: http://dx.doi.org/10.1016/j.tree.2014.04.004

Computer-aided visualization and analysis of fossils has
revolutionized the study of extinct organisms. Novel techniques allow
fossils to be characterized in three dimensions and in unprecedented
detail. This has enabled paleontologists to gain important insights
into their anatomy, development, and preservation. New protocols allow
more objective reconstructions of fossil organisms, including soft
tissues, from incomplete remains. The resulting digital
reconstructions can be used in functional analyses, rigorously testing
long-standing hypotheses regarding the paleobiology of extinct
organisms. These approaches are transforming our understanding of
long-studied fossil groups, and of the narratives of organismal and
ecological evolution that have been built upon them.


•Computer-aided visualization and analysis has revolutionized the
study of fossils.
•Fossils can now be characterized in three dimensions and in
unprecedented detail.
•The resulting digital reconstructions can be used in rigorous
functional analyses.
•Hypotheses regarding the function of extinct organisms can therefore be tested.

News release:




Bipedalism in lizards

Christofer J. Clemente (2014)
The evolution of bipedal running in lizards suggests a consequential
origin may be exploited in later lineages.
Evolution (advance online publication)
DOI: 10.1111/evo.12447

The origin of bipedal locomotion in lizards is unclear. Modelling
studies have suggested that bipedalism may be an exaptation, a
byproduct of features originally designed to increase maneuverability,
which were only later exploited. Measurement of the body center of
mass in 124 species of lizards confirms a significant rearward shift
among bipedal lineages. Further racetrack trials showed a significant
acceleration threshold between bipedal and quadrupedal runs. These
suggest good general support for a passive bipedal model, in which the
combination of these features lead to passive lifting of the front of
the body. However, variation in morphology could only account for 56%
of the variation in acceleration thresholds, suggesting that dynamics
have a significant influence on bipedalism. Deviation from the passive
bipedal model was compared with node age, supporting an increase in
the influence of dynamics over time. Together, these results show that
bipedalism may have first arisen as a consequence of acceleration and
a rearward shift in the BCOM, but subsequent linages have exploited
this consequence to become bipedal more often, suggesting that
bipedalism in lizards may convey some advantage. Exploitation of
bipedalism was also associated with increased rates of phenotypic
diversity, suggesting exploiting bipedalism may promote adaptive



Angolan Mesozoic marine reptiles



Fortungavis news release



New ichthyosaur specimen preserved with soft tissues displayed at
Jura-Museum in Eichstätt (in German)



Extracting dinosaur fossils from surrounding matrix



Dinosaur fossil poaching



Darwinius 5 years on

The controversies surrounding Darwinius (nicknamed Ida [EE-dah]) have
not been fully resolved since the taxon was first described five years

Jørn Hurum recently worked with members of a number of rock groups to
mark the 5-year anniversary of Darwinius with a music video presenting
his side:




Last thylacine bit cameraman on the butt