James L Patton | University of California, Berkeley (original) (raw)

Papers by James L Patton

Proceedings of the Biological Society of Washington., 2003

Molecular Phylogenetics and Evolution, Mar 1, 2005

The phylogeny of South American spiny rats (Rodentia; Echimyidae) was studied using the exon 28 o... more The phylogeny of South American spiny rats (Rodentia; Echimyidae) was studied using the exon 28 of the von Willebrand Factor nuclear gene (vWF). Sequences were analysed separately and in combination with a mitochondrial dataset (cyt b, 12S and 16S rRNAs) used in previous publications. The basal polytomy of echimyids was partially resolved and unexpected intergeneric clades were recovered. Thus, the intimate nested position of Myocastor within echimyids is evidenced. A well-supported clade is identified, including all the arboreal genera, and a group formed by Myocastor, Thrichomys, and Proechimys+Hoplomys. The clustering of Euryzygomatomys+Clyomys with Trinomys is also suggested. On the opposite, the phylogenetic position of Capromys as well as the relationships among arboreal genera remain unclear. Molecular divergence times were estimated using a Bayesian relaxed molecular clock and suggest a Middle Miocene origin for most of modern genera. The ecomorphological diversification of echimyids is discussed in the light of these new results and past environmental modifications in South America.

Molecular Phylogenetics and Evolution, Apr 1, 2003

Molecular Phylogenetics and Evolution, Dec 1, 2002

We analyzed the phylogenetic relationships of echimyid genera based on sequences of the cytochrom... more We analyzed the phylogenetic relationships of echimyid genera based on sequences of the cytochrome b, 12S, and 16S mitochondrial genes. Our results corroborate the monophyly of Octodontoidea and the rapid diversification of echimyid rodents as previously proposed. The analyses indicate that the family Echimyidae, including Myocastor to the exclusion of Capromys, is paraphyletic, since Capromys and Myocastor are well-supported sister-taxa. We therefore suggest the inclusion of both Capromys and Myocastor in the family Echimyidae. Five other suprageneric clades are well supported: Dactylomys+Kannabateomys, Euryzygomatomys+Clyomys, Proechimys+Hoplomys, Mesomys+Lonchothrix, and Makalata+(Echimys+Phyllomys). Trinomys and Thrichomys have no clear close relatives, and Isothrix emerged as sister to Mesomys+Lonchothrix, but with no support. We suggest that most of the cladogenesis leading to the extant echimyid genera probably occurred during the Late Miocene, about eight million years ago.

Journal of Mammalogy, Dec 10, 2020

Journal of Mammalogy, 2021

Proceedings of the Royal Society B: Biological Sciences, 2016

Phenotypic (co)variation is a prerequisite for evolutionary change, and understanding how (co)var... more Phenotypic (co)variation is a prerequisite for evolutionary change, and understanding how (co)variation evolves is of crucial importance to the biological sciences. Theoretical models predict that under directional selection, phenotypic (co)variation should evolve in step with the underlying adaptive landscape, increasing the degree of correlation among co-selected traits as well as the amount of genetic variance in the direction of selection. Whether either of these outcomes occurs in natural populations is an open question and thus an important gap in evolutionary theory. Here, we documented changes in the phenotypic (co)variation structure in two separate natural populations in each of two chipmunk species ( Tamias alpinus and T. speciosus ) undergoing directional selection. In populations where selection was strongest (those of T. alpinus ), we observed changes, at least for one population, in phenotypic (co)variation that matched theoretical expectations, namely an increase of ...

Molecular Biology and Evolution, 1991

Biological Journal of the Linnean Society, 2016

Nesse documento atualiza-se a lista dos mam feros que ocorrem no Brasil, incluido formas terrestr... more Nesse documento atualiza-se a lista dos mam feros que ocorrem no Brasil, incluido formas terrestres, aqu ticas e marinhas. De acordo com os dados existentes, o pa s possui 483 mam feros continentais e 41 marinhos, totalizando 524 esp cies, distribu das em 11 ordens, 46 ...

PeerJ, 2020

The taxonomic history ofEuryoryzomys legatushas been complex and controversial, being either incl... more The taxonomic history ofEuryoryzomys legatushas been complex and controversial, being either included in the synonymy of other oryzomyine species or considered as a valid species, as in the most recent review of the genus. Previous phylogenetic analyses segregatedE. legatusfromE. russatus, its putative senior synonym, but recovered it nested withinE. nitidus. A general lack of authoritative evaluation of morphological attributes, details of the chromosome complement, or other data types has hampered the ability to choose among alternative taxonomic hypotheses, and thus reach a general consensus for the status of the taxon. Herein we revisit the status ofE. legatususing an integrated approach that includes: (1) a morphological review, especially centered on specimens from northwestern Argentina not examined previously, (2) comparative cytogenetics, and (3) phylogenetic reconstruction, using mitochondrial genes.Euryoryzomys legatusis morphologically and phylogenetically distinct from ...

Occasional Papers of the Museum of Natural Science, Louisiana State University, 1976

Mammalia, 2017

Field expeditions in 2011 that inventoried the terrestrial vertebrate fauna of two wildlife prote... more Field expeditions in 2011 that inventoried the terrestrial vertebrate fauna of two wildlife protected areas in the tropical Caribbean of Guatemala have produced the first confirmed records of two bats for the country: the white-bellied big-eared bat,

Journal of Mammalogy, 1997

Journal of Mammalogy, 2020

We combine morphological (qualitative and quantitative data) and genetic (one mitochondrial and o... more We combine morphological (qualitative and quantitative data) and genetic (one mitochondrial and one nuclear gene) data from a large set of specimens of Octodon from the four currently recognized living species of the genus. The integration of the results (qualitative assessment, multivariate analysis of cranial measurements, and gene trees) allows us to state that 1) the current taxonomic scheme does not reflect the species diversity of Octodon; 2) in particular, as currently understood O. bridgesii likely is a complex of three species; 3) one of these, encompassing the southern populations of the genus, in the Araucanía Region (Chile) and Neuquén Province (Argentina), is named and described here as a new species; and 4) the mitochondrial gene tree departs from the nuclear gene tree with respect to O. pacificus and the new species here described.