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1.
Nature ; 445(7129): 757-60, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17301791

RESUMO

One of the biggest challenges for conservation biology is to provide conservation planners with ways to prioritize effort. Much attention has been focused on biodiversity hotspots. However, the conservation of evolutionary process is now also acknowledged as a priority in the face of global change. Phylogenetic diversity (PD) is a biodiversity index that measures the length of evolutionary pathways that connect a given set of taxa. PD therefore identifies sets of taxa that maximize the accumulation of 'feature diversity'. Recent studies, however, concluded that taxon richness is a good surrogate for PD. Here we show taxon richness to be decoupled from PD, using a biome-wide phylogenetic analysis of the flora of an undisputed biodiversity hotspot--the Cape of South Africa. We demonstrate that this decoupling has real-world importance for conservation planning. Finally, using a database of medicinal and economic plant use, we demonstrate that PD protection is the best strategy for preserving feature diversity in the Cape. We should be able to use PD to identify those key regions that maximize future options, both for the continuing evolution of life on Earth and for the benefit of society.


Assuntos
Biodiversidade , Evolução Biológica , Conservação dos Recursos Naturais/métodos , Fenômenos Fisiológicos Vegetais , Efeito Estufa , Dados de Sequência Molecular , Filogenia , Plantas/classificação , Plantas/genética , Plantas Medicinais/classificação , Plantas Medicinais/genética , Plantas Medicinais/fisiologia , Densidade Demográfica , África do Sul
2.
Cladistics ; 22(6): 495-532, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34892896

RESUMO

The phylogenetic relationships, biogeography and classification of, and morpho-behavioral (M/B) evolution in, gamebirds (Aves: Galliformes) are investigated. In-group taxa (rooted on representatives of the Anseriformes) include 158 species representing all suprageneric galliform taxa and 65 genera. The characters include 102 M/B attributes and 4452 nucleic acid base pairs from mitochondrial cytochrome b (CYT B), NADH dehydrogenase subunit 2 (ND2), 12S ribosomal DNA (12S) and control region (CR), and nuclear ovomucoid intron G (OVO-G). Analysis of the combined character data set yielded a single, completely resolved cladogram that had the highest levels of jackknife support, which suggests a need for a revised classification for the phasianine galliforms. Adding 102 M/B characters to the combined CYT B and ND2 partitions (2184 characters) decisively overturns the topology suggested by analysis of the two mtDNA partitions alone, refuting the view that M/B characters should be excluded from phylogenetic analyses because of their relatively small number and putative character state ambiguity. Exclusion of the OVO-G partition (with > 70% missing data) from the combined data set had no effect on cladistic structure, but slightly lowered jackknife support at several nodes. Exclusion of third positions of codons in an analysis of a CYT B + ND2 partition resulted in a massive loss of resolution and support, and even failed to recover the monophyly of the Galliformes with jackknife support. A combined analysis of putatively less informative, "non-coding" characters (CYT B/ND2 third position sites + CR +12S + OVO-G sequences) yielded a highly resolved consensus cladogram congruent with the combined-evidence cladogram. Traditionally recognized suprageneric galliform taxa emerging in the combined cladogram are: the families Megapodiidae (megapodes), Cracidae (cracids), Numididae (guineafowls), Odontophoridae (New World quails) and Phasianidae (pheasants, pavonines, partridges, quails, francolins, spurfowls and grouse) and the subfamilies Cracinae (curassows, chachalacas and the horned guan), Penelopinae (remaining guans), Pavoninae sensu lato (peafowls, peacock pheasants and argus pheasants), Tetraoninae (grouse) and Phasianinae (pheasants minus Gallus). The monophyly of some traditional groupings (e.g., the perdicinae: partridges/quails/francolins) is rejected decisively, contrasted by the emergence of other unexpected groupings. The most remarkable phylogenetic results are the placement of endemic African galliforms as sisters to geographically far-distant taxa in Asia and the Americas. Biogeographically, the combined-data cladogram supports the hypothesis that basal lineages of galliforms diverged prior to the Cretaceous/Tertiary (K-T) Event and that the subsequent cladogenesis was influenced by the break-up of Gondwana. The evolution of gamebirds in Africa, Asia and the Americas has a far more complicated historical biogeography than suggested to date. With regard to character evolution: spurs appear to have evolved at least twice within the Galliformes; a relatively large number of tail feathers (≥ 14) at least three times; polygyny at least twice; and sexual dimorphism many times.

3.
Ann Bot ; 87(2): 191-208, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32050736

RESUMO

Phylogenetic analyses of nucleotide and amino acid sequences of the chloroplast protein coding gene rps4 were performed for 225 species of mosses, representing 84% of families recognized by Vitt (1984. In: Schuster RM, ed. New manual of bryology , vol 2 . Nichinan: Hattori Botanical Laboratory), under the criterion of maximum parsimony with Takakia and Sphagnum as outgroups. Most parsimonious topologies converge to a scenario wherein the Andreaeidae are monophyletic and sister to the Bryidae (peristomate mosses), the Nematodonteae and the Buxbaumiaceae form a monophyletic lineage, the Diphysciaceae are sister to the Arthrodonteae and, within the latter, the Funarineae-Encalyptineae-Timmiaceae-Haplolepideae compose a monophyletic clade sister to remaining diplolepideous mosses. This hypothesis suggests that early in the evolution of the Arthrodonteae, two major lineages diverged, with opposite and alternate peristomes, respectively. Bootstrap support for the deep dichotomies is poor or lacking but increases when protein translations of rps 4 sequences are included in the analysis. Several novel systematic hypotheses are raised, including ( a ) a diplolepideous rather than haplolepideous origin of the Pleurophascaceae; ( b ) an affinity of the Catascopiaceae with the Funariineae rather than the Bryineae; and ( c ) a close relationship of the Calomniaceae and Mitteniaceae to the Rhizgoniaceae. The advantages and disadvantages of a single gene phylogeny are discussed with respect to the identification of polyphyletic familial or suprafamilial taxa.

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