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Re: Cloudy With A Chance of New Papers



 Bhullar, B.-A.S., and Bever, G.S. 2009. An archosaur-like
 laterosphenoid in early turtles (Reptilia: Pantestudines). Breviora
 518:1-11.

 ABSTRACT: Turtles are placed with increasing consistency by molecular
 phylogenetic studies within Diapsida as sister to Archosauria, but
 published gross morphologyâbased phylogenetic analyses do not recover
 this position. Here, we present a previously unrecognized unique
 morphological character offering support for this hypothesis: the
 presence in stem turtles of a laterosphenoid ossification identical
 to that in Archosauriformes. The laterosphenoid is a tripartite
 chondrocranial ossification, consisting of an ossified pila antotica,
 pila metoptica, and taenia medialis + planum supraseptale. It forms
 the anterior border of the exit for the trigeminal nerve (V) and
 partially encloses the exits for cranial nerves III, IV, and II. This
 ossification is unique to turtles and Archosauriformes within
 Vertebrata. It has been mistakenly dismissed as anatomically
 dissimilar in these two groups in the past, so we provide a complete
 description and detailed analysis of correspondence between turtles
 and Archosauriformes in each of its embryologically distinct
 components. A preliminary phylogenetic analysis suggests other
 potential  synapomorphies of turtles and archosaurs, including a row
 or rows of mid-dorsal dermal ossifications.

(Thanks to Augusto Haro for having posted this earlier. I didn't have time to respond.)

I presume the laterosphenoid isn't simply the good old pleurosphenoid...?

The osteoderms are not convincing. Turtles (*Odontochelys* included) have one row of osteoderms dorsal to the neural spines; archosaurs have an even number of osteoderms dorsal to the epaxial musculature, _never_ a median one dorsal to the neural spines.

 Prauss, M.L. 2009. The K/Pg boundary at Brazos-River, Texas, USA --
 an approach by marine palynology. Palaeogeography, Palaeoclimatology,
 Palaeoecology. doi: 10.1016/j.palaeo.2009.09.024.

 ABSTRACT: Two cores and one outcrop section from the
 Cretaceous/Palaeogen (K/Pg) boundary interval at the Brazos-River
 area, Texas, USA, have been high resolution sampled and analysed
 fully quantitatively by marine palynology. The results have been
 compared and integrated with data from micropalaeontology,
 sedimentology and isotope-geochemistry from the same sections. Within
 all three sections, the K/Pg boundary, defined as the base of the P0
 foraminifera zone and the onset of a negative carbon isotope anomaly,
 closely corresponds to the appearance of lowermost Danian
 organic-walled dinocysts.

Keep this in mind for a moment...

 [...] Thus, prominent
 paleo-environmental changes and sea-level fluctuations precede and
 coincide with the K/Pg boundary proper. These data are inconsistent
 with a single âcatastrophicâ impact as the cause for the K/Pg
 boundary eve! nt, but s uggest relative longer term environmental
 stress as finally leading to End-Cretaceous crisis of the biosphere.

How so? Why can't it suggest that all those climate and sea level changes had little impact on biodiversity? Where does the "finally leading to" part come from? After all, there's a carbon isotope anomaly in there, distinct from the usual ebb and flow (see above).

 Roberts, E.M., O'Connor, P.M., Stevens, N.J., Gottfried, M.D.,
 Jinnah, Z.A., Ngasala, S., Choh, A.M., and Armstrong, R.A. 2009.
 Sedimentology and depositional environments of the Red Sandstone
 Group, Rukwa Rift Basin, southwestern Tanzania: new insight into
 Cretaceous and Paleogene terrestrial ecosystems and tectonics in
 sub-equatorial Africa. Journal of African Earth Sciences. doi:
 10.1016/j.jafrearsci.2009.09.002

Progress!!! Just too bad there's no Maastrichtian or Paleocene there yet.

 Ji, Q., Luo, Z.-X., Zhang, X., Yuan, C.-X., and Xu, L. 2009.
 Evolutionary development of the middle ear in Mesozoic therian
 mammals. Science 326:278-281. doi: 10.1126/science.1178501.

 ABSTRACT: The definitive mammalian middle ear (DMME) is defined by
 the loss of embryonic Meckel's cartilage and disconnection of the
 middle ear from the mandible in adults. It is a major feature
 distinguishing living mammals from nonmammalian vertebrates. We
 report a Cretaceous trechnotherian mammal with an ossified Meckel's
 cartilage in the adult, showing that homoplastic evolution of the
 DMME occurred in derived therian mammals, besides the known cases of
 eutriconodonts. The mandible with ossified Meckel's cartilage appears
 to be paedomorphic. Reabsorption of embryonic Meckel's cartilage to
 disconnect the ear ossicles from the mandible is patterned by a
 network of genes and signaling pathways. This fossil suggests that
 developmental heterochrony and gene patterning are major mechanisms
 in homplastic evolution of the DMME.

Incredible what you miss when your institution has no access to Science (except old issues via JSTOR) or for that matter Nature.

 Elzanowski, A., and Stidham, T.A. 2009. Morphology of the quadrate in
 the Eocene anseriform Presbyornis and extant galloanserine birds.
 Journal of Morphology. doi: 10.1002/jmor.10799.

Does the paper say anything about *Vegavis*...?