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Pasquet E Pons JM Fuchs J Cruaud C Bretagnolle V 《Molecular phylogenetics and evolution》2007,45(1):158-167
We address the phylogenetic relationships of the drongos (Dicruridae) at the species-level using sequences from two nuclear (myoglobin intron-2 and c-mos) and two mitochondrial (ND2 and cytochrome b) loci. The resulting phylogenetic tree shows that the most basal species is D. aeneus, followed in the tree by a trichotomy including (1) the Asian D. remifer, (2) a clade of all African and Indian Ocean islands species as well as two Asian species (D. macrocercus and D. leucophaeus) and (3) a clade that includes all other Asian species as well as two Australasian species (D. megarhynchus and D. bracteatus). Our phylogenetic hypotheses are compared to [Mayr, E., Vaurie, C., 1948. Evolution of the family Dicruridae (Birds). Evolution 2, 238-265.] hypothetical family "tree" based on traditional phenotypic analysis and biogeography. We point out a general discrepancy between the so-called "primitive" or "unspecialized" species and their position in the phylogenetic tree, although our results for other species are congruent with previous hypotheses. We conduct dating analyses using a relaxed-clock method, and propose a chronology of clades formation. A particular attention is given to the drongo radiation in Indian Ocean islands and to the extinction-invasion processes involved. The first large diversification of the family took place both in Asia and Africa at 11.9 and 13.3Myr, respectively, followed by a dispersal event from Africa to Asia at ca 10.6Myr; dispersal over Wallace line occurred later at ca 6Myr. At 5Myr, Principe and Indian Ocean Islands have been colonized from an African ancestor; the most recent colonization event concerned Anjouan by an immigrating population from Madagascar. 相似文献
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The Brachypteraciidae is an avian family endemic to Madagascar. Members of this family were mist-netted in Madagascar, and blood smears were made to screen for the presence of hematozoa. Smears were stained with Giemsa and examined at x100, x160, and x1000 for hematozoa. Three new species of avian hematozoa from wild-caught ground-rollers in Madagascar are described. Haemoproteus goodmani n. sp. is found in the pitta-like ground-roller (Atelornis pittoides), whereas Haemoproteus forresteri n. sp. and Leucocytozoon frascai n. sp. are from the rufous-headed ground-roller (Atelornis crossleyi). These represent the first hematozoa described from this family. 相似文献
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To date, limited surveys have been conducted on the endemic avifauna of Madagascar with regard to hematozoa. Wild-caught birds from the Vangidae, endemic to Madagascar and the Comoros Islands, were mist-netted, and blood smears were made. Slides were examined for the presence of hematozoa at x100, x160, and x1000 using a light microscope. Parasites were measured using established techniques, and morphometrics were compared. On the basis of their distinctive morphologies and morphometrics, 4 new species of avian hematozoa are described in this study. Haemoproteus vangii n. sp. and Leucocytozoon lairdi n. sp. occur in the blue vanga (Cyanolanius madagascarinus), whereas Haemoproteus madagascariensis n. sp. and Leucocytozoon bennetti n. sp. are described from the hook-billed vanga (Vanga curvirostris). These represent the first hematozoa described from this family. 相似文献
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The haemoproteids of the flowerpecker family Dicaeidae are reviewed. Two new species, Haemoproteus dicaeus and H. nucleophilus, are described. Haemoproteus nucleophilus appears to be endemic in the dicaeids endemic to the New Guinea archipelago. 相似文献
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Common myna(Acridotherus tristis) and jungle myna(Acridotherus fuscus) forage in pure and mixed flocks of various sizes in fallow lands. These flocks were often found associated with drongos that
forage individually on the insects herded out by the movements of the flocking myna. We report here the benefits and costs
of such association to drongos and mynas. Drongos had a tendency to associate with larger (> 21) than smaller (<20) flocks
irrespective of the species composition of the flocks. Drongos associated with larger flocks showed increased foraging trips
and harvested more insects in a given time than those that were either isolated or were associated with small flocks. The
food range of drongos and mynas differed significantly indicating that they do not compete with each other. Thus our results
indicate that drongos are benefitted by this association; however this association neither benefits nor costs to the mynas.
The association between the drongos and mynas therefore appears to be commensalistic. 相似文献
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Investigators of haematozoa of the Timaliidae have reported the presence of two species of Leucocytozoon Berestneff, 1904, i.e. L. liothricis Laveran & Marullaz, 1914 and L. timaliae Bennett, Earlé & Pierce, 1993. Blood films collected from 42 wild-caught babblers in Madagascar were stained and examined for the presence of haematozoa using a compound microscope. To date, no species of avian haematozoa have been reported from babblers in Madagascar, although haematozoa have been observed. In the present study, we report a new species of Leucocytozoon, L. atkinsoni n. sp., whose morphometrics fall between those reported for the two previously described species from timaliids. The parasite is capped by the host cell nucleus covering 38% of its perimeter. L. atkinsoni n. sp. was found to have a marked, intensely staining, nucleolus as well as vacuoles in the parasite cytoplasm, in contrast to both L. liothricis and L. timaliae. Remnants of the host cell cytoplasm are commonly observed in cells infected with L. atkinsoni, a characteristic not reported in association with either of the previously described species from these hosts. 相似文献
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The 34 valid species of avian Plasmodium are listed with their authorities and type-hosts. Plasmodium species are also listed by the avian family in which they occur and by the number of avian families and species which they parasitise. A key to the subgenera of Plasmodium occurring in birds is presented. The distribution of the parasites by the Wallacean life zones is discussed; Plasmodium records in birds from the Australian zone is sharply lower than for any other life zone. 相似文献
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Diversification across major biogeographic breaks in the African Shining/Square‐tailed Drongos complex (Passeriformes: Dicruridae)
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Surprisingly, little is known about the extent of genetic structure within widely distributed and polytypic African species that are not restricted to a particular habitat type. The few studies that have been conducted suggested that speciation among African vertebrates may be intrinsically tied to habitat and the dynamic nature of biome boundaries. In the present study, we assessed the geographic structure of genetic variation across two sister‐species of drongos, the Square‐tailed Drongo (Dicrurus ludwigii) and the Shining Drongo (D. atripennis), that are distributed across multiple sub‐Saharan biogeographic regions and habitat types. Our results indicate that D. ludwigii consists of two strongly divergent lineages, corresponding to an eastern–southern lineage and a central‐western lineage. Furthermore, the central‐western lineage may be more closely related to D. atripennis, a species restricted to the Guineo‐Congolian forest block, and it should therefore be ranked as a separate species from the eastern–southern lineage. Genetic structure is also recovered within the three primary lineages of the D. atripennis–D. ludwigii complex, suggesting that the true species diversity still remains underestimated. Additional sampling and data are required to resolve the taxonomic status of several further populations. Overall, our results suggest the occurrence of complex diversification patterns across habitat types and biogeographic regions in sub‐Saharan Africa birds. 相似文献
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Phylogenetic distribution of the novel avian endogenous provirus family EAV-0 总被引:3,自引:1,他引:2
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A new family of related endogenous proviruses, existing at 50 to 100 copies per haploid genome and distinguishable by remarkably short long terminal repeats, has been described for domestic chickens (Gallus gallus subsp domesticus). In this communication, by using Southern blot analysis and probes derived from both internal viral sequences and locus-specific, cellular flanking sequences, we studied the genetic distribution of this family of moderately repetitive avian endogenous retroviruses within the genomes of four Gallus species. Eight inbred lines of domestic chickens, the evolutionary progenitor to the domestic chicken (red jungle fowl), and two more distantly related species (grey and green jungle fowl) were studied. All Gallus species harbored this class of elements, although the different lines of domestic chickens and different species of jungle fowl bore distinguishable complements of the proviral loci. Jungle fowl appeared to have fewer copies than domestic chickens. For three randomly isolated proviral loci, domestic chickens (G. gallus subsp. domesticus) and red jungle fowl (G. gallus subsp. gallus) showed only a proviral state, whereas the most primitive and divergent of the jungle fowl, the green jungle fowl (G. varius), consistently demonstrated only preintegration states or disparate alleles. The presence of this family in all Gallus species and of related sequences in other genera suggests that a primordial founding integration event occurred prior to the evolutionary separation of Gallus species and possibly related genera. Additionally, at least one proviral locus has been acquired subsequent to speciation, indicating that this family was actively infectious after the primary founding event. This conserved, repetitive proviral family appears to represent the vestigial remnant of an avian retrovirus class related to and evolutionarily more ancient than the Rous-associated virus-0 family of avian endogenous retroviruses. 相似文献
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The haemoproteids of the avian suboscine families Eurylaimidae and Pittidae are reviewed. Haemoproteus eurylaimus n. sp. and H. pittae n. sp. are described. 相似文献
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William A. Wells 《The Journal of cell biology》2004,164(7):952-953
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The histotopography of the silvery-white glistening carotid body and the branchial derivates in the cranial thoracic inlets as well as the histocytology of the particular organ were revealed by various microtechniques. Three types of randomly distributed epithelioid cells, many capillaries, and small and large sinuses are observable. Myelinated fibres are sparsely distributed. 25 clinically healthy white leghorn males were used for this investigation. 相似文献
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Robert J. Etches 《Transgenic research》2006,15(6):791-792
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Etches RJ 《Transgenic research》2006,15(5):521-526
After 25 years, the search for the avian cell that can be cultured indefinitely, genetically modified, and clonally derived while retaining its ability to enter the germline has ended. van de Lavoir et al. [2006a, Nature 441:766–769] have defined the conditions for culture and genetic modification of primordial germ cells (PGCs) and shown that these cells are transmitted at high rates through the germline. The advent of this technology provides the ability to introduce transgenes of any size and to make site-specific changes to the genome. Although PGCs are committed to the germline, they can be induced into somatically committed embryonic germ (EG) cells by changing the culture conditions. EG cells resemble embryonic stem (ES) cells that are also committed to the somatic lineages (van de Lavoir 2006b, Mech Dev 123:31–41). These cell-based systems facilitate insertion of larger transgenes that provide high level, developmentally regulated and tissue-specific expression in transgenic chimeras and their offspring. Following introduction of a transgene, high-grade somatic chimeras can be made with ES and EG cells within 4 weeks and 4 months respectively, allowing quick assessment of the transgenic phenotype. Following introduction of a tansgene into PGCs, high-grade germline chimeras can be made within 8–9 weeks and the high rate of germline transmission of G0 chimeras produces a large cohort of transgenic chicks in 16–17 weeks. PGC, EG and ES cells can be grown in conventional laboratory settings and small flocks of recipient birds or third-party vendors can supply recipient embryos to make somatic and/or germline chimeras. In general, animal management is routine although some specialized equipment and technical skill is required to incubate chimeras in surrogate shells.An erratum to this article can be found at 相似文献