A Late Jurassic digging mammal and early mammalian diversification.
نویسندگان
چکیده
A fossil mammal from the Late Jurassic Morrison Formation, Colorado, has highly specialized teeth similar to those of xenarthran and tubulidentate placental mammals and different from the generalized insectivorous or omnivorous dentitions of other Jurassic mammals. It has many forelimb features specialized for digging, and its lumbar vertebrae show xenarthrous articulations. Parsimony analysis suggests that this fossil represents a separate basal mammalian lineage with some dental and vertebral convergences to those of modern xenarthran placentals, and reveals a previously unknown ecomorph of early mammals.
منابع مشابه
We incorporated the dental and vertebral similarities of Fruitafossor, tubulidentates, and xenarthrans into global parsimony analysis of morphological features known for Mesozoic mammals and the major groups of extant mam-
similarities of Fruitafossor, tubulidentates, and xenarthrans into global parsimony analysis of morphological features known for Mesozoic mammals and the major groups of extant mammals (3, 7, 17). Fruitafossor is resolved to be a basal mammal emerging in the Late Jurassic mammalian diversification and has no closer relationship to placental xenarthrans than have other nonplacental trechnotheria...
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عنوان ژورنال:
- Science
دوره 308 5718 شماره
صفحات -
تاریخ انتشار 2005