Consulta: subjectFacets:"Divergence times"
Registros recuperados: 3
Data/hora: 09/06/2024 10:26:48

Diversification of Ramphastinae (Aves, Ramphastidae) prior to the Cretaceous/Tertiary boundary as shown by molecular clock of mtDNA sequences
Provedor de dados: 74
Autores: Nahum,Laila Alves; Pereira,Sérgio Luiz; Campos Fernandes,Flora Maria de; Russo Matioli,Sergio; Wajntal,Anita.
Partial cytochrome b and 12S rDNA mitochondrial DNA sequences of eight representatives of the Ramphastidae family were analyzed. We applied the linearized tree method to identify sequences evolving at similar rates and estimated the divergence times among some of the taxa analyzed. After excluding Ramphastos tucanus and Capito dayi from our data set, the remaining taxa presented a constant rate of DNA substitution, and branch lengths could be re-estimated with a clock constraint using the maximum likelihood method. Branch lengths were calibrated assuming that Galliformes and Piciformes split around 100 million years ago (mya). Our results indicate that Ramphastinae, and probably Capitoninae, diverged from other Piciformes in the Late Cretaceous (~82 mya),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Divergence times; K/T; Mass extinction; Cytochrome b; 12S rDNA; Paleogeography; Phylogeny.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000400003

Locked in the icehouse: evolution of an endemic Epimeria (Amphipoda, Crustacea) species flock on the Antarctic shelf
Provedor de dados: 5
Autores: Verheye, Marie L.; Backeljau, Thierry; D'Acoz, Cedric D'Udekem.
The Antarctic shelf’s marine biodiversity has been greatly influenced by the climatic and glacial history of the region. Extreme temperature changes led to the extinction of some lineages, while others adapted and flourished. The amphipod genus Epimeria is an example of the latter, being particularly diverse in the Antarctic region. By reconstructing a time-calibrated phylogeny based on mitochondrial (COI) and nuclear (28S and H3) markers and including Epimeria species from all oceans, this study provides a temporal and geographical framework for the evolution of Antarctic Epimeria. The monophyly of this genus is not supported by Bayesian Inference, as Antarctic and non-Antarctic Epimeria form two distinct well-supported clades, with Antarctic Epimeria...
Tipo: Text
Palavras-chave: Amphipoda; Southern ocean; Historical biogeography; Phylogeny; Divergence times; Diversification.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00386/49712/83605.pdf

Study in Agaricus subgenus Minores and allied clades reveals a new American subgenus and contrasting phylogenetic patterns in Europe and Greater Mekong Subregion
Provedor de dados: 16
Autores: Chen, J.; Callac, P.; Parra, L.A.; Karunarathna, S.C.; He, M.-Q.; Moinard, M.; De Kesel, A.; Raspé, O.; Wisitrassameewong, K.; Hyde, K.D.; Zhao, R.-L.
Within Agaricus subg. Minores, A. sect. Minores remains a little-studied section due generally to its delicate sporocarps often lacking taxonomically relevant morphological characters. To reconstruct the section, using the recent taxonomic system based on divergence times, and to evaluate the species diversity of A. sect. Minores in the Greater Mekong Subregion, 165 specimens were incorporated in phylogenetic analyses. A dated tree based on nuclear ITS, LSU and tef1-α sequence data allowed us to better circumscribe A. subg. Minores and to propose a new subgenus, A. subg. Minoriopsis, which is only known from tropical and subtropical regions of the Americas. A larger tree based on ITS sequences indicated that, with 81 phylogenetic species, the reconstructed...
Tipo: Article / Letter to the editor
Palavras-chave: Agaricaceae; Agaricus sect. Minores; Divergence times; Multi-gene phylogeny; Taxonomy.
Ano: 2017
URL: http://www.repository.naturalis.nl/record/628990