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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. © The Willi Hennig Society 2006.  相似文献   
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Introduction

NIMH Project Accept (HPTN 043) is a community- randomized trial to test the safety and efficacy of a community-level intervention designed to increase testing and lower HIV incidence in Tanzania, Zimbabwe, South Africa and Thailand. The evaluation design included a longitudinal study with community members to assess attitudinal and behavioral changes in study outcomes including HIV testing norms, HIV-related discussions, and HIV-related stigma.

Methods

A cohort of 657 individuals across all sites was selected to participate in a qualitative study that involved 4 interviews during the study period. Baseline and 30-month data were summarized according to each outcome, and a qualitative assessment of changes was made at the community level over time.

Results

Members from intervention communities described fewer barriers and greater motivation for testing than those from comparison communities. HIV-related discussions in intervention communities were more grounded in personal testing experiences. A change in HIV-related stigma over time was most pronounced in Tanzania and Zimbabwe. Participants in the intervention communities from these two sites attributed community-level changes in attitudes to project specific activities.

Discussion

The Project Accept intervention was associated with more favorable social norms regarding HIV testing, more personal content in HIV discussions in all study sites, and qualitative changes in HIV-related stigma in two of five sites.  相似文献   
3.
The monotypic Stone Partridge Ptilopachus petrosus (Galliformes: Phasianidae), restricted to arid rocky areas of the northern savanna belt including the Sahel on the southern border of the Sahara Desert, is a taxonomic enigma. Historically, it has been grouped with Asian forest partridges (Galloperdix and Bambusicola spp.). However, recent DNA‐based phylogenetic research has suggested that its closest relative is Nahan's Francolin Francolinus nahani, another taxonomically enigmatic African galliform, and a globally threatened, narrow endemic species associated with the interior of remnant primary forests of the eastern equatorial lowlands of the Democratic Republic of the Congo and Uganda. This hypothesis is investigated in greater detail using additional DNA evidence and information on behaviour and vocalizations. Phylogenetic analyses of the combined sequences from three nuclear and four mitochondrial markers (5554 bases for 84 galliform taxa) overwhelmingly support the sister relationship between F. nahani and P. petrosus. They, in turn, are the distantly related sister taxon of the New World quails (Odontophoridae), and are not related to any other Old World galliform.  相似文献   
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