Abstract: Echimyidae is a species-rich clade of Neotropical rodents, which diversified in association with forested biomes. A few lineages were adapted to open environments from southern South America since the late Miocene. Eumysops is one of these southern echimyids, and its peculiar craniomandibular morphology has been assumed to be a result of adaptation to open environments. We performed a geometric morphometric analysis of craniomandibular shape variation in order to explore if Eumysops is, as suspected,...

Supplemental material for : O’Gorman, J. P. 2019. Elasmosaurid phylogeny and paleobiogeography, with a reappraisal of Aphrosaurus furlongi from the Maastrichtian of the Moreno Formation. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2019.1692025. Supp Mat 1.pdf (scoring modifications and new characters) Supp Mat 2.nex (data set)

Evolutionary transitions between quadrupedal and bipedal postures are pivotal to the diversification of amniotes on land, including in our own lineage (Hominini). Heterochrony is suggested as a macroevolutionary mechanism for postural transitions, but understanding postural evolution in deep time is hindered by a lack of methods for inferring posture in extinct species. Dinosaurs are an excellent natural laboratory for understanding postural transitions, because their lineage contains at least four instances of quadrupedality evolving from bipedality,...

The family Ampullariidae includes both aquatic and amphibious apple snails. They are an emerging model for evolutionary studies due to the high diversity, ancient history and wide geographical distribution. Insight into drivers of ampullariid evolution is hampered, however, by the lack of genomic resources. Here we report the genomes of four ampullariids spanning the Old World (Lanistes nyassanus) and New World (Pomacea canaliculata, Pomacea maculata and Marisa cornuarietis) clades. The ampullariid genomes have conserved ancient...

The living tree sloths Choloepus and Bradypus are the only remaining members of Folivora, a major xenarthran radiation that occupied a wide range of habitats in many parts of the western hemisphere during the Cenozoic, including both continents and the West Indies. Ancient DNA evidence has played only a minor role in folivoran systematics, as most sloths lived in places not conducive to genomic preservation. Here we utilize collagen sequence information, both separately and in...