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The Placental Mammal Ancestor and the Post–K-Pg Radiation of Placentals
A phylogenetic tree shows that crown clade Placentalia and placental orders originated after the K-Pg boundary, but phenomic signals overturn molecular signals to show Sundatheria (Dermoptera + Scandentia) as the sister taxon of Primates, a close link between Proboscidea and Sirenia (sea cows), and the monophyly of echolocating Chiroptera (bats). Expand
Transient Floral Change and Rapid Global Warming at the Paleocene-Eocene Boundary
Floral response to warming and/or increased atmospheric CO2 during the PETM was comparable in rate and magnitude to that seen in postglacial floras and to the predicted effects of anthropogenic carbon release and climate change on future vegetation. Expand
New Paleocene skeletons and the relationship of plesiadapiforms to crown-clade primates
The results, based on the fossil record, unambiguously place plesiadapiforms with Euprimates and indicate that the divergence of Primates (sensu lato) from other euarchontans likely occurred before or just after the Cretaceous/Tertiary boundary (65 Mya), notably later than logistical model and molecular estimates. Expand
Grasping Primate Origins
It is inferred that the ancestor of Euprimates was primitively an arboreal grasper adapted for terminal branch feeding rather than a specialized leaper or visually directed predator. Expand
Affinities of ‘hyopsodontids’ to elephant shrews and a Holarctic origin of Afrotheria
As the oldest record of an afrothere clade, identification of macroscelidean relatives in the North American Palaeocene argues against an African origin for Afrotheria, weakening support for linking placental diversification to the break-up of Gondwana. Expand
Semicircular canal system in early primates.
Fossil primates reconstructed are reconstructed as having been similarly agile to omomyids and derived notharctid adapoids, which suggests that when postcranial material is found for this species it will exhibit features for some leaping behaviour, or for a locomotor mode requiring a similar degree of agility. Expand
Giant boid snake from the Palaeocene neotropics reveals hotter past equatorial temperatures
Depositional environments and faunal composition of the Cerrejón Formation indicate an anaconda-like ecology for the giant snake, and an earliest Cenozoic origin of neotropical vertebrate faunas. Expand
Systematics and Biogeography of Crocodylians from the Miocene of Panama
A cladistic analysis of 32 alligatorid and three outgroup taxa resulted in 1210 equally most parsimonious cladograms, all of which suggest that Culebrasuchus mesoamericanus, gen. et sp. Expand
Paleohydrologic response to continental warming during the Paleocene–Eocene Thermal Maximum, Bighorn Basin, Wyoming
Abstract Geologically rapid global warming occurred during the Paleocene–Eocene Thermal Maximum (PETM) ~ 56 Ma. Several studies have argued that important changes occurred in the hydrological cycleExpand
Virtual endocast of Ignacius graybullianus (Paromomyidae, Primates) and brain evolution in early primates
A virtual endocast reconstructed from ultra high resolution X-ray computed tomography data for the paromomyid plesiadapiform Ignacius graybullianus from the early Eocene of Wyoming is described, allowing for an unprecedented study of both size and fine details of anatomy. Expand