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A article in Ethinic and Racial Studies by Walls and Williams makes inferences about religious discrimination in employment from interview data. We question the validity of treating lay people as experts and present large-scale data from two recent surveys and the 2001 Census which suggest that sectarianism is more a social myth than a social reality.  相似文献   

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Conservation, precaution, and Caribbean reefs   总被引:6,自引:0,他引:6  
Some authors argue that overfishing is an important reason that reef corals have declined in recent decades. Their reasoning is that overfishing removes herbivores, releasing macroalgae to overgrow and kill the corals. The evidence suggests, however, that global climate change and emergent marine diseases make a far greater contribution to coral mortality, and that macroalgae generally grow on the exposed skeletal surfaces of corals that are already dead. Macroalgal dominance, therefore, is an effect rather than a cause of coral mortality. Marine protected areas (MPAs), which are usually established to protect stocks of reef fish, foster populations of herbivorous fish under at least some circumstances. Increased herbivory can reduce algal cover, potentially accelerating the recovery of coral populations inside MPAs; however, establishing MPAs will have only a limited impact on coral recovery unless policymakers confront the accelerating negative effects of the global-scale sources of coral mortality.  相似文献   

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Self-Help Housing, the Poor, and the State in the Caribbean. Robert B. Potter and Dennis Conway. eds. Knoxville: University of Tennessee Press, 1997. 299 pp.  相似文献   

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Sacred Possessions: Vodun, Santeria, Obeah and the Caribbean. Margarite Fernandez Olmos and Iizbeth Paravisini-Gerbert. eds. New Brunswick, NJ: Rutgers University Press, 1997. 312 pp.  相似文献   

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The structure of the axillary organ of a batrachoidid species, the gulf toadfish (Opsanus beta Goode and Bean 1879), has been examined and several simple experiments designed to elucidate its function performed. Electron microscopy (EM) studies revealed cells and structures suggesting secretory and iono regulatory roles (e.g., abundant intracytoplasmic secretory particles, rough endoplasmic reticulum, sparse Golgi bodies, indented epithelial cells with microvilli, numerous endocytotic vesicles, etc.). Our physiological experiments allowed us to reach several conclusions: the organs do not excrete significant quantities of urea relative to other areas of the fish (head and gills), the organs do not secrete a substance that is toxic to a teleost test fish (Gambusia affinis), the secretions do not induce short-term modifications in locomotory activity of other gulf toadfish (e.g., by pheromonal means) and the secretions do not inhibit the growth of several species of microorganisms in culture. The function of the organ and its secretions remains unknown, representing a fertile area for research on structure and function in comparative physiology.  相似文献   

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Macrourimegatrema gadoma n. sp. (Digenea: Opecoelidae: Plagioporinae) is described from the pyloric caeca and intestine of the doublethread grenadier Gadomus arcuatus (Goode & Bean) (Macrouridae) collected from the northeastern Gulf of Mexico and off Venezuela. The new species differs from Macrourimegatrema brayi Blend, Dronen & Armstrong, 2004, the type and only species in the genus, in the distribution of the vitelline follicles and gonads, a larger body size, and the presence of highly-folded caeca with numerous outpocketings or pouches. It is suggested that species of Macrourimegatrema Blend, Dronen & Armstrong, 2004 probably infect their piscine hosts through the ingestion of a benthopelagic crustacean.  相似文献   

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Body composition (lipid, water, protein, energy content) and metamorphosis of young-of-the-year gulf menhaden, Brevoortia patronus Goode, were examined over a yearly cycle in Fourleague Bay, Louisiana. Metamorphosis from larvae to juveniles, as indicated by the body depth to length ratio, was completed by 30 mm S.L. Analysis of the length/weight relationship indicated separate equations for larvae/postlarvae (< 30 mm S.L.) and juvenile/subadults (30–100 mm S.L.). Major body composition changes from larvae to subadult included an increase in lipid content, a corresponding increase in energy content, and a decrease in nitrogen content. Young-of-the-year gulf menhaden did not exhibit the seasonal pattern of condition factors typical of adult clupeids. There may be a shift in energy allocation away from protein growth to lipid storage associated with attainment of a larger size. Initiation of emigration may be related to lipid storage and temperature change, with higher lipid content fish migrating first. End-of-year variations in fish size and lipid storage may be related to environmental conditions, such as water temperature and salinity.  相似文献   

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Reproductive cycling and oocyte development were examined for female tilefish, Lopholatilus chamaeleonticeps Goode and Bean, captured in the South Atlantic Bight, U.S.A. A total of 752 female tilefish was collected during 15 sampling periods from May 1982 to December 1983. Reproductive cycling was quantified using four techniques: gross visual estimation of ovarian stages, histological examination of ovaries, follicle diameter measurements, and an ovarian index. The relative accuracies of these techniques also were evaluated. All four methods indicated that L. chamaeleonticeps was capable of spawning from March to June. Most spawning occurred between April and June. Ovarian development was positively correlated with the change in daylength. Follicular development was asynchronous, which is characteristic of multiple spawners. Folliculogenesis was similar to that in most oviparous teleosts.  相似文献   

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Patterns of human kinship commonly involve preferential treatment of relatives based on lineal descent (lineages) rather than degree of genetic relatedness (kindreds), presenting a challenge for inclusive fitness theory. Here, we examine effects of lineage and kindred characteristics on reproductive success (RS) and number of grandchildren for 130 men and 124 women in a horticultural community on Dominica. Kindreds had little effect on fitness independently of lineage characteristics. Fitness increased with the number of lineal relatives residing in the community but decreased beyond an apparently optimal lineage size, suggesting resource enhancement and competition among kin. Female-biased patrilineage sex ratio was positively associated with men’s fitness, while male-biased matrilineage sex ratio was positively associated with women’s fitness. Number of brothers in the community was negatively associated with men’s, but not women’s, fitness. Parents and number of sisters had no effect on either male or female reproduction; however, women with younger sisters had higher RS, suggesting benefits of kin support for childcare. In sum, imposed norms for lineage social organization may enhance lineal ancestors’ inclusive fitness at a cost to individual inclusive fitness. Research was supported by grants from the National Science Foundation (BNS 8920569 and SBR 9205373); the University of Missouri Research Board to MVF; the Earthwatch Center for Field Research to MVF, Marsha B. Quinlan, and RJQ; and the B.S.U. Center for International Programs and Office of Academic Research and Sponsored Programs to RJQ. Marsha Quinlan and Napoleon Chagnon provided valuable advice on earlier drafts. Ed Hagen gave generous help with Descent software for kinship analysis. Many friends, teachers, and consultants in Bwa Mawego contributed generously to this study: the Durand clan—Juranie, Jonah, Elford, Induria, Margelia, Eugenia, Lillia, Elquimedo, Zexia, Delfine, Wilford, Nathalie, and Sarah; the Warringtons—Martina, Amatus, Onia, Belltina, Zabius, Sarah-Gene, and Heckery; the Laudats—Eddie, Benedict, and Dellie; the Laurents—Aron and Tito; the Lewises—Eddie, Melanie, Eulina, Spliffy, Ganjala, Julina, Jalina, and Marietta; Franklin Vigilante; Lawrence Prosper; Edmund Sanderson; Alex and Tita Alie; and especially Mistress Didi and Mr. McField Coipel. Rob Quinlan is Assistant Professor of Anthropology at Ball State University. His main interests include human evolutionary ecology, reproductive development, parental care, kinship, and medical anthropology. He has conducted fieldwork in Dominica since 1993. Mark Flinn is Associate Professor of Anthropology and Psychological Sciences at the University of Missouri-Columbia. His main interests include evolutionary theory, childhood stress, family relationships, and health. He has conducted fieldwork in Dominica every year since 1987.  相似文献   

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Afro/Creole: Power,. pposition, and Play in the Caribbean. Richard D. E. Burton. Idiaca and London: Cornell University Press, 1997.298 pp.  相似文献   

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Previous research on the Caribbean coral Montastraea cavernosa reported the presence of cyanobacterial endosymbionts and nitrogen fixation in orange, but not brown, colonies. We compared the diversity of nifH gene sequences between these two color morphs at three locations in the Caribbean and found that the nifH sequences recovered from M. cavernosa were consistent with previous studies on corals where members of both the α-proteobacteria and cyanobacteria were recovered. A number of nifH operational taxonomic units (OTUs) were significantly more abundant in the orange compared to the brown morphs, and one specific OTU (OTU 17), a cyanobacterial nifH sequence similar to others from corals and sponges and related to the cyanobacterial genus Cyanothece, was found in all orange morphs of M. cavernosa at all locations. The nifH diversity reported here, from a community perspective, was not significantly different between orange and brown morphs of M. cavernosa.  相似文献   

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Recharting the Caribbean: Land, Law, and Citizenship in the British Virgin Islands. Bill Maurer. Ann Arbor: University of Michigan Press, 1997. 301 pp.  相似文献   

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