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Full-Text Articles in Life Sciences
More Than Movement – Ant Seed Dispersal Inhibits Phytopathogenic Fungi, Charlene H. Gray
More Than Movement – Ant Seed Dispersal Inhibits Phytopathogenic Fungi, Charlene H. Gray
Biology Theses
Seed dispersal by ants is a cosmopolitan mutualism involving thousands of plant species. Ants gain a food reward (elaiosomes) from the plant seed, and ant-mediated plants gain several presumed benefits, including dispersal away from parent plants and placement in 'safe site' microhabitat. Higher plant germination and survival in ant nest soils has been attributed to higher levels of nutrients, aeration, and soil moisture than surrounding soils, but evidence in support of these benefits is inconsistent. Ants secrete anti-microbial compounds that inhibit microbial pathogens. I explore the possibility that ants transfer anti-microbial properties to the soil they inhabit, and there is …
Natal Philopatry In Song Sparrows (Melospiza Melodia) Predicts Female Cellular Versus Humoral Immune Function, But Does Not Consistently Predict Parasitism, Heather L. Macgillivray
Natal Philopatry In Song Sparrows (Melospiza Melodia) Predicts Female Cellular Versus Humoral Immune Function, But Does Not Consistently Predict Parasitism, Heather L. Macgillivray
Electronic Thesis and Dissertation Repository
Parasites vary geographically and dispersing host individuals may encounter different strains and wider varieties than their philopatric counterparts. Previously observed lower parasite counts in philopatric than dispersing birds have been suggested to be the result of local adaptation to parasites, but I suggest an alternative: these patterns may result from differing immune function. I used genetic assignment tests to infer natal philopatry of song sparrows (Melospiza melodia), and tested whether this predicted parasitism and innate and adaptive immune function. I found no relationship between parasitism and philopatry, in contrast to previous findings. In females, philopatry was associated with …
Ecological And Evolutionary Interactions Between Song Sparrows (Melospiza Melodia) And Their Bloodborne Parasites, Yanina Sarquis-Adamson
Ecological And Evolutionary Interactions Between Song Sparrows (Melospiza Melodia) And Their Bloodborne Parasites, Yanina Sarquis-Adamson
Electronic Thesis and Dissertation Repository
Local adaptation is the result of natural selection operating at a local scale, such that trade-offs in fitness across different environments result in individuals having higher fitness in their place of origin than when transported into a foreign environment. Populations may become locally adapted to features of their abiotic environment, or in the case of coevolutionary arms races between hosts and parasites, to other species comprising their biotic environment. If host populations are adapted to their local (sympatric) parasites, or conversely if parasites are adapted to their local hosts, then interactions with local parasite strains may influence the fitness consequences …