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Marine reptiles from Jurassic of Beaujolais, France and other new papers



From: Ben Creisler
bcreisler@gmail.com

A few new non-dino papers of interest:

Peggy Vincent, Jeremy E. Martin, Valentin Fischer, Guillaume Suan,
Bouziane Khalloufi, Baptiste Suchéras-Marx, Alex Léna, Kévin Janneau,
Bruno Rousselle and Louis Rulleau (2013)
Marine vertebrate remains from the Toarcian–Aalenian succession of
southern Beaujolais, Rhône, France.
Geological Magazine (advance online publication)
DOI: http://dx.doi.org/10.1017/S0016756812000982
http://128.232.233.5/action/displayAbstract?fromPage=online&aid=8854925&fulltextType=RA&fileId=S0016756812000982


A previously undocumented marine vertebrate fauna comprising
ichthyosaur, plesiosaur, marine crocodilian and fish remains from the
Toarcian–Aalenian succession at Lafarge quarry, southern Beaujolais
(Rhône, France) is described on the basis of both historical
collections and new discoveries. The taxonomic composition of the
Lafarge quarry marine vertebrate assemblage highlights its
cosmopolitan nature and strong relationships with taxa known from
elsewhere in Europe. Several groups are recorded for the first time in
the Toarcian–Aalenian succession of France, implying new
palaeobiogeographic interpretations and prompting discussion of marine
amniote diversity during this interval.

===


F. Witzmann, B. M. Rothschild, O. Hampe, G. Sobral, Y. M. Gubin &  P.
Asbach (2013)
Congenital Malformations of the Vertebral Column in Ancient Amphibians.
Anatomia, Histologia, Embryologia (advance online publication)
DOI: 10.1111/ahe.12050
http://onlinelibrary.wiley.com/doi/10.1111/ahe.12050/abstract

Temnospondyls, the largest group of Palaeozoic and Mesozoic
amphibians, primitively possess rhachitomous vertebrae with
multipartite centra (consisting of one horse-shoe-shaped inter- and
paired pleurocentra). In a group of temnospondyls, the stereospondyls,
the intercentra became pronounced and disc-like, whereas the
pleurocentra were reduced. We report the presence of congenital
vertebral malformations (hemi, wedge and block vertebrae) in Permian
and Triassic temnospondyls, showing that defects of formation and
segmentation in the tetrapod vertebral column represent a fundamental
failure of somitogenesis that can be followed throughout tetrapod
evolution. This is irrespective of the type of affected vertebra, that
is, rhachitomous or stereospondylous, and all components of the
vertebra can be involved (intercentrum, pleurocentrum and neural
arch), either together or independently on their own. This is the
oldest known occurrence of wedge vertebra and congenital block
vertebra described in fossil tetrapods. The frequency of vertebral
congenital malformations in amphibians appears unchanged from the
Holocene.


===


Robert J. Knell, Darren Naish, Joseph L. Tomkins & David W.E. Hone (2013)
Is sexual selection defined by dimorphism alone? A reply to Padian and Horner.
Trends in Ecology and Evolution (Letter) (advance online publication)
http://dx.doi.org/10.1016/j.tree.2013.02.007
http://www.sciencedirect.com/science/article/pii/S0169534713000591


==

parental care in turtles:

Camila R. Ferrara, Richard C. Vogt & Renata S.Sousa-Lima (2013)
Turtle vocalizations as the first evidence of posthatching parental
care in chelonians.
Journal of Comparative Psychology 127(1): 24-32
doi: 10.1037/a0029656
http://psycnet.apa.org/journals/com/127/1/24/

Until recently, freshwater turtles were thought to be silent reptiles,
neither vocalizing nor hearing very well. We recorded individuals in
nature, captivity, and during interactions between adults and
hatchlings and show that hatchlings and adult turtles, Podocnemis
expansa, produce sounds in and out of the water. Sounds were emitted
by hatchlings inside the egg, in open nests, in the river, and in
captive conditions. Adult females were recorded producing sounds in
the river, while basking, while nesting, and in captivity. Females
were recorded in the river approaching and responding to hatchling
sounds. We detected 2,122 sounds, classified in 11 different types.
These data suggest that there is sound communication between adults
and hatchings and that these sounds may be used to congregate
hatchlings with adults for mass migration. Hatchlings and females with
transmitters were found migrating together. We consider these findings
as the first evidence of acoustic communication mediating posthatching
parental care in chelonians. We anticipate that our findings will
influence the way turtle behavior is studied and interpreted, and add
communication and sound pollution to turtle conservation concerns.

===

Lewis G. Halsey (2013)
The relationship between energy expenditure and speed during
pedestrian locomotion in birds: A morphological basis for the elevated
y-intercept?
Comparative Biochemistry and Physiology Part A: Molecular &
Integrative Physiology (advance online publication)
http://dx.doi.org/10.1016/j.cbpa.2013.03.027
http://www.sciencedirect.com/science/article/pii/S1095643313000913



The slope of the typically linear relationship between metabolic rate
and walking speed represents the net cost of transport (NCOT). The
extrapolated y-intercept is often greater than resting metabolic rate,
thus representing a fixed cost associated with pedestrian transport
including body maintenance costs. The full cause of the elevated
y-intercept remains elusive and it could simply represent experimental
stresses. The present literature-based study compares the
mass-independent energetic cost of pedestrian locomotion in birds
(excluding those with an upright posture, i.e. penguins), represented
by the y-intercept, to a known predictor of cost of transport, hip
height. Both phylogenetically informed and non-phylogenetically
informed analyses were undertaken to determine if patterns of
association between hip height, body mass, and the y-intercept are
robust with respect to the method of analysis. Body mass and hip
height were significant predictors of the y-intercept in the best
phylogenetically-informed and non-phylogenetically informed models.
Thus it seems that, in birds at least, the elevated y-intercept is a
legitimate component of locomotion energy expenditure. Hip height is
probably a good proxy of effective limb length and thus perhaps birds
with greater hip heights have lower y-intercepts because their longer
legs more efficiently accommodate body motion and/or because their
limbs are more aligned with the ground reaction forces.