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dc.contributor.advisorMartin F. Polz.en_US
dc.contributor.authorPreheim, Sarah Pacochaen_US
dc.contributor.otherWoods Hole Oceanographic Institution.en_US
dc.date.accessioned2010-09-02T14:56:01Z
dc.date.available2010-09-02T14:56:01Z
dc.date.copyright2010en_US
dc.date.issued2010en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/58184
dc.descriptionThesis (Ph.D.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and the Woods Hole Oceanographic Institution), 2010.en_US
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references.en_US
dc.description.abstractExtensive genetic diversity has been discovered in the microbial world, yet mechanisms that shape and maintain this diversity remain poorly understood. This thesis investigates to what extent populations of the gamma-proteobacterial family, Vibrionaceae, are ecologically specialized by investigating the distribution across a wide range of environmental categories, such as marine invertebrates or particles in the water column. Additionally, it seeks to determine whether in situ population distributions directly result from a competitive advantage over other Vibrio populations. This was investigated by in vitro competition assays on mixtures of native, sterilized particles. Generalist populations were found to dominate the associations with marine invertebrates, consistent with a model of high migration dominated population assembly. A majority of populations occurred broadly within and among the different types of invertebrates sampled, with one population being a near perfect generalist with regard to seasons, host taxa and body regions. High variability across host individuals, consistent with a scenario of stochastic clonal expansion, was especially pronounced in crab and zooplankton samples. Specialization, demonstrated by specific and reproducible association with different particle types in the water column, is more common than specialization within invertebrate hosts.en_US
dc.description.abstract(cont.) Co-existing Vibrio species show strong preferences for different types of particulate matter in the water column suggesting that competition for limited resources influences their evolution. While populations show different growth profiles on particle derived substrates, relative growth advantages of specialist populations in competition with other Vibrio populations on native particles may not be sufficient to explain observed environmental distributions. Instead, populations may gain an advantage on these particles by colonizing the living plant or zooplankton prior to death and degradation into particulate matter. In summary, although vibrios are known commensals of marine invertebrates, evidence suggests that population structure within animals is fairly weak compared to suspended particles in the water column. This highlights the importance of comparing multiple environmental categories and migration among them to investigate population structure and adaptation.en_US
dc.description.statementofresponsibilityby Sarah Pacocha Preheim.en_US
dc.format.extent183 p.en_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectJoint Program in Oceanography.en_US
dc.subjectCivil and Environmental Engineering.en_US
dc.subjectWoods Hole Oceanographic Institution.en_US
dc.subject.lcshMarine microbiologyen_US
dc.subject.lcshMicrobial diversityen_US
dc.titleEcology and population structure of vibrionaceae in the coastal oceanen_US
dc.typeThesisen_US
dc.description.degreePh.D.en_US
dc.contributor.departmentJoint Program in Oceanographyen_US
dc.contributor.departmentWoods Hole Oceanographic Institutionen_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Civil and Environmental Engineering
dc.identifier.oclc639534801en_US


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