Wandering across time
Article Abstract:
The discovery of fossils from a therapsid or mammal-like reptile in the upper Paleocene Paskapoo Formation in Alberta, Canada, extends the known existence of these animals to 100 million years later than was previously thought. Therapsids are believed to be the evolutionary link between reptiles and mammals. Fox and colleagues, who found the fossils, call the new animal Chronoperates paradoxus and classify it as a therapsid based on several anatomical features such as the tooth enamel's microstructure. However, this classification will remain tentative until further evidence proves it.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
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Epipubic bones in eutherian mammals from the Late Cretaceous of Mongolia
Article Abstract:
It has been possible to positively identify the presence of epipubic bones in two separate eutherian lineages. It is possible that these groups are located in a basal position in the Eutheria. The fact that epipubic bones have been seen in two Cretaceous eutherians indicates that the significant changes associated with typical placental reproduction may have occurred later in the development of the Eutheria. The presence of epipubic bones and the lengthy external attachment of young does not prove that these traits are functionally dependent on each other.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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Implications of Deltatheridium specimens for early marsupial history
Article Abstract:
Two new specimens of Deltatheridium pretrituberculare from Ukhaa Tolgod, a Mongolian Late Cretaceous locality, are described. One specimen includes an adult partial skull, complete lower jaws and two ulnae, while the second comprised juvenile jaws, disarticulated skull bones and some postcranial elements. They provide information on tooth replacement and on lower jaw basicranial morphology.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
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