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The lance‐tailed manakin (Chiroxiphia lanceolata) is a lek‐breeding bird from Central America in which males court females with complex cooperative displays. To resolve detailed patterns of paternity in the wild, we isolated and characterized 12 novel microsatellite loci in this species. Eleven of these loci were polymorphic (five to 14 alleles), with observed heterozygosities ranging from 0.36 to 0.87 (N = 574 individuals). We tested for linkage disequilibrium using randomized subsamples of adults to control for known family structure among long‐lived and sedentary individuals. These loci will be valuable in resolving paternity among many candidate fathers in this species. 相似文献
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SUMMARY. 1. Zooplankton populations in a small, natural, tropical lake are dominated by a few, small-sized taxa including the copepod Thermo- cyclops consimilis , the cladoceran Moina micrura and several rotifer species.
2. Moina micrura and adults of Thermocyclops consimilis undergo diel vertical migrations within the water column. Population densities of T. consimilis show marked intra-annual variations which may to some extent be related to variations in rainfall and to lunar periodicities In predator abundance.
3. The diets of Chaoborus lavae include other Chaoborus , Cladocera, Copepoda. Rotifera and the dinoflagellate Peridinium. The diets of late instars of the largest species, edulis , were dominated by Crustacea, while those of the two smaller species. C, ceratopogones and C. anomalus , were dominated by Rotifera and the dinoflagellate alga Peridinium , as were the diets of early instars of all species. Algae have not been previously reported to be a large component of the diet of Chaoborus populations in nature.
4. Some of the dietary differences among Chaoborus instars and species are related to the size of each prey species in relation to the mouth gape of each instar. However, there are also important differences in electivity among instars of different species of the same size. 相似文献
2. Moina micrura and adults of Thermocyclops consimilis undergo diel vertical migrations within the water column. Population densities of T. consimilis show marked intra-annual variations which may to some extent be related to variations in rainfall and to lunar periodicities In predator abundance.
3. The diets of Chaoborus lavae include other Chaoborus , Cladocera, Copepoda. Rotifera and the dinoflagellate Peridinium. The diets of late instars of the largest species, edulis , were dominated by Crustacea, while those of the two smaller species. C, ceratopogones and C. anomalus , were dominated by Rotifera and the dinoflagellate alga Peridinium , as were the diets of early instars of all species. Algae have not been previously reported to be a large component of the diet of Chaoborus populations in nature.
4. Some of the dietary differences among Chaoborus instars and species are related to the size of each prey species in relation to the mouth gape of each instar. However, there are also important differences in electivity among instars of different species of the same size. 相似文献
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CARTER T. ATKINSON ELLIS C. GREINER DONALD J. FORRESTER 《The Journal of eukaryotic microbiology》1986,33(3):375-381
ABSTRACT. Two generations of pre-erythrocytic schizogony occurred in skeletal and cardiac muscle of domestic turkeys infected with sporozoites of Haemoproteus meleagridis. First generation schizonts reached maturity approximately five days post-inoculation (DPI) and developed in capillary endothelial cells and myofibroblasts. The schizonts ranged from 12 to 20 μm in diameter and produced long (5–6 μm), slender merozoites. Early second generation schizonts were first detected in capillary endothelial cells between 5 and 8 DPI. They were cylindrical and ranged in size from 5 to 8 μm in diameter and up to 28 μm in length. Second generation schizonts which reached maturity by 17 DPI were surrounded by a thick, hyaline wall and were packed with numerous spherical merozoites less than 1 μm in diameter. Mature megaloschizonts were fusiform, ranged from 30 to 113 μm in diameter, and extended as much as 465 μm along the long axis of muscle fibers. Merozoites developed as buds from cytomeres that formed between 8 and 14 DPI. Infected turkeys developed a moderate to severe myositis within 5 DPI and were lame in one or both legs. The myositis was associated with the necrosis of scattered groups of muscle fibers. Muscle fibers surrounding mature megaloschizonts were swollen and hyaline. Megaloschizonts were surrounded occasionally by fibroblasts and infiltrates of mononuclear cells. The morphology and site of development of mature megaloschizonts of Haemoproteus meleagridis are contrasted with those of other avian haemosporidians. 相似文献
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J. A. L. WATSON W. V. BROWN L. R. MILLER F. L. CARTER M. J. LACEY 《Systematic Entomology》1989,14(3):299-325
Abstract Heterotermes ferox (Froggatt) auctt. is shown to be a complex of species, each characterized by the composition of cuticular hydrocarbons in the worker, by canonical variate scores calculated from eight measurements of the soldier, and by small differences in the size and shape of the alate. H.ferox is redefined and two species are described, H.brevicatena sp.n. and H.longicatena sp.n. 相似文献