Eutherians Cretácico y Laurasian origen para los mamíferos placentarios cerca de la frontera K / T
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Updated: Feb 17, 2026
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Using Archival Japanese Paper and Thermoplastic Resins to Prepare Fossils for Storage, Display, Transport, and Radiography
Published on: November 14, 2025
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J R Wible1, G W Rougier, M J Novacek
1Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania 15206, USA. wiblej@carnegiemnh.org
Nature
|June 22, 2007
Resumen
El origen de los mamíferos placentarios ahora se coloca cerca del límite Cretácico / Terciario, no antes en el Cretácico. Las nuevas evidencias fósiles y el análisis filogenético excluyen los fósiles del Cretácico de Placentalia.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- La filogenética es la filogenética.
Sus antecedentes:
- Las estimaciones para el origen de los mamíferos placentarios varían ampliamente, con estudios de ADN que sugieren orígenes a lo largo del período Cretácico y interpretaciones paleontológicas que difieren en la evidencia fósil.
- Faltaba un análisis filogenético integral que incorporara fósiles del Cretácico y una diversa morfología de mamíferos placentarios para resolver este debate.
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