Re: Cloudy With A Chance of New Papers

[David Marjanovic <david.marjanovic@gmx.at>]

>  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*...?