Topic
Caviomorpha
About: Caviomorpha is a research topic. Over the lifetime, 107 publications have been published within this topic receiving 3910 citations.
Papers published on a yearly basis
Papers
TL;DR: The phylogenetic results reaffirm the African origin of South American rodents and support a trans-Atlantic dispersal of these mammals during Middle Eocene times, and further extends the gap between first appearances of rodents and primates in South America.
Abstract: The long-term isolation of South America during most of the Cenozoic produced a highly peculiar terrestrial vertebrate biota, with a wide array of mammal groups, among which caviomorph rodents and platyrrhine primates are Mid-Cenozoic immigrants. In the absence of indisputable pre-Oligocene South American rodents or primates, the mode, timing and biogeography of these extraordinary dispersals remained debated. Here, we describe South America's oldest known rodents, based on a new diverse caviomorph assemblage from the late Middle Eocene (approx. 41 Ma) of Peru, including five small rodents with three stem caviomorphs. Instead of being tied to the Eocene/Oligocene global cooling and drying episode (approx. 34 Ma), as previously considered, the arrival of caviomorphs and their initial radiation in South America probably occurred under much warmer and wetter conditions, around the Mid-Eocene Climatic Optimum. Our phylogenetic results reaffirm the African origin of South American rodents and support a trans-Atlantic dispersal of these mammals during Middle Eocene times. This discovery further extends the gap (approx. 15 Myr) between first appearances of rodents and primates in South America.
299 citations
TL;DR: The phylogenetic relationships among 23 Hystricognathi species are reconstructed using a nuclear marker, and it is suggested that Chinchillidae and Dinomyidae are sister clades, Abrocomidae is a true Octodontoidea, and Capromyidae, Echimyidae, and Myocastoridae cluster together.
240 citations
Journal Article•
236 citations
TL;DR: The discovery of South America's earliest rodent in the central Chilean Andes provides information critical to resolving the source area and primitive morphology of South American caviomorphs, suggesting an African origin for the group as discussed by the authors.
Abstract: THE mid-Cenozoic immigration of rodents and primates to South America (when it was widely isolated by oceans) represents a pre-eminent problem in the biogeographical history of placental mammals. The unexpected discovery of South America's earliest rodent in the central Chilean Andes provides information critical to resolving the source area and primitive morphology of South American caviomorphs, suggesting an African origin for the group. This rodent is part of a new fossil mammal fauna1, the first diverse assemblage known for a critical 15–25 million year gap in the fossil record. We report here that cooccurrence of numerous higher-level taxa otherwise restricted to older or younger intervals identifies this fauna as representing a new biochronological interval preceding the Deseadan (South American Land Mammal Age), previously the earliest occurrence of rodents and primates on the continent. Radioisotopic dating corroborates biostratigraphy in identifying the new Andean rodent as the earliest known from the continent.
177 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 7 |
| 2020 | 8 |
| 2019 | 5 |
| 2018 | 3 |
| 2017 | 8 |
| 2016 | 3 |