Culminating Project Title
Date of Award
Culminating Project Type
Biological Sciences - Cell and Molecular: M.S.
College of Science and Engineering
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Keywords and Subject Headings
Climate Change, Endocrine Disruption, Behavior, Life Stage, Fathead Minnow
Human-mediated environmental impacts can induce changes in the expression of complex behaviors within individuals, and alter the outcomes of interactions between individuals. Although the independent effects of a number of important stressors on aquatic biota are well documented (e.g., exposure to environmental contaminants), fewer studies have examined how natural variation in the ambient environment modulates these effects. In this study, factorial experiments were conducted to assess the influences of temperature and estrogen concentration on two life stages of fathead minnow (Pimephales promelas). Larval and adult minnows were exposed for 21 or 30 days, respectively, to 3 concentrations of estrone (nominally at 25, 125, and 625 ng/L) or to an ethanol carrier control (0 ng/L), at four water temperatures (15, 18, 21, and 24 °C) reflecting natural seasonal variation. A series of behavioral experiments were conducted to assess the independent and interactive effects of temperature and estrogen exposure on intra- and interspecific interactions in three contexts with important fitness consequences (i.e., reproductive behavior, foraging, and predator evasion). In addition, a series of anatomical and physiological endpoints were explored to assess the independent and interactive effects of chemical exposure on plasma vitellogenin induction, blood glucose, hematocrit, histology, and morphometric indices. Evidence was obtained suggesting that thermal regime can modulate the effects of exposure on larval survival, larval predator-prey interactions, and adult physiological and anatomical endpoints, even within a relatively narrow range of ambient temperatures. These findings improve our understanding of the outcomes of interactions between anthropogenic stressors and natural abiotic environmental factors, and suggest that such interactions can have ecological and evolutionary implications for freshwater populations and communities.
Cox, Megan K., "Modulation of Estrogenic Effects Via Temperature on Two Life Stages of Fathead Minnow" (2016). Culminating Projects in Biology. 16.