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Judd A Case Francisco J. Goin Michael O. Woodburne 《Journal of Mammalian Evolution》2005,12(3-4):461-494
Newly described marsupial specimens of Judithian (late Campanian) and Lancian (Maastrichtian) age in the western interior
of North America (Wyoming to Alberta) have dental morphologies consistent with those expected in comparably aged sediments
in South America (yet to be found). Three new Lancian species are referable to the didelphimorphian Herpetotheriidae, which
suggests that the ameridelphian radiation was well under way by this time. The presence of a polydolopimorphian from Lancian
deposits with a relatively plesiomorphic dental morphology and an additional polydolopimorphian taxon from Judithian deposits
with a more derived molar form indicate that this lineage of typically South American marsupials was diversifying in the Late
Cretaceous of North America. This study indicates that typical South American lineages (e.g. didelphimorphians and polydolopimorphians)
are not the result of North American peradectian progenitors dispersing into South America at the end of the Cretaceous (Lancian),
or at the beginning of the Paleocene (Puercan), and giving rise to the ameridelphian marsupials. Instead, these lineages,
and predictably others as well, had their origins in North America (probably in more southerly latitudes) and then dispersed
into South America by the end of the Cretaceous. Geophysical evidence concerning the connections between North and South America
in the Late Cretaceous is summarized as to the potential for overland mammalian dispersal between these places at those times.
Paleoclimatic reconstructions are considered, as is the dispersal history of hadrosaurine dinosaurs and boid snakes, as to
their contribution to an appraisal of mammalian dispersals in the Late Cretaceous. In addition, we present a revision of the
South American component of the Marsupialia. One major outcome of this process is that the Polydolopimorphia is placed as
Supercohort Marsupialia incertae sedis because no characteristics currently known from this clade securely place it within one of the three named marsupial cohorts.
This article contains corrections to the text and a new Figure 11 not incorporated in the originally published version in
Vol. 11, Nos. 3/4. For purposes of future citation, the present version (Vol. 12 and Nos. 3/4) should be used. 相似文献
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Isolation and characterization of a new atrial peptide-degrading enzyme from bovine kidney. 总被引:1,自引:0,他引:1
L Toll S R Brandt C M Olsen A K Judd R G Almquist 《Biochemical and biophysical research communications》1991,175(3):886-893
An endopeptidase isolated from bovine kidney displays high affinity and selectivity for the Ser-Phe bond located in the C-terminal region of atrial peptides. Enzymatic activity converts APIII and APII to the less active peptide API. This peptidase is inhibited by both metal chelators and sulfhydryl-reactive agents, suggesting both a tightly bound metal and a cysteine residue are important for enzymatic activity. This enzyme may be important for the processing and/or degradation of atrial peptides. 相似文献
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