Kairomones are infochemicals that benefit a heterospecific receiver. Chaoborus spp. release a kairomone from their gut when feeding on Daphnia spp. Daphnia respond to kairomone by shifting life history parameters or producing neonates with induced morphological defenses, increasing their chance of survival. When laboratory-cultured Daphnia are exposed to environmentally-relevant metal concentrations, a kairomone response is not induced, increasing predation vulnerability. Currently Daphnia live in metal-contaminated lakes in Sudbury, ON. It is possible the extant population is tolerant of relatively high copper (Cu) concentrations and can still induce a kairomone response. In comparison, it is hypothesized clones found in lakes isolated from anthropogenic sources of metal-contamination would be less tolerant as they have not been exposed to high Cu concentrations. The purpose of this study was to examine how multiple clones of D. pulicaria obtained from lakes along a Cu gradient respond to kairomone in the absence and presence of copper. Several different clones from Ontario lakes located in the Canadian Shield were exposed to environmentally-relevant Cu concentrations and Chaoborus kairomone. Neonates were collected and measured to assess predator-induced defenses. Results indicate that kairomone-mediated responses and Cu-tolerance vary among D. pulicaria clones. Clones from the Sudbury area were able to induce a response to kairomone when exposed to Cu, indicating a Cu-tolerance. However, this was not true for all Sudbury clones. In contrast, most clones from clean lakes did not respond to kairomone when exposed to Cu; while some clones exhibited a Cu-tolerance. Clones that were not tolerant of Cu were affected at concentrations much lower than those predicted by the Biotic Ligand Model (BLM) that induce acute toxicity. Predictions generated by the BLM can be conservative making them useful when creating water quality criteria; however, my results indicate these predictions can also be under-protective. Chemosensory cues mediate vital life processes that are essential for survival. Populations may be devastated if metals interfere with chemosensory cues. Overall, the results of my study suggest that genetic variation is important for population establishment and maintenance, specifically when exposed to multiple stressors, and that directional selection may result in stress tolerance. / Thesis (Master, Biology) -- Queen's University, 2009-12-23 09:50:46.152

Thesis (M.A.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 46-52). / 52 leaves, bound ill. 29 cm

Thesis (M.A.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 52-58). / viii, 58 leaves, bound ill. 29 cm

Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references. / Also available by subscription via World Wide Web / vi, 92 leaves, bound ill. 29 cm

Thesis (M.A.)--Georgia Southern University, 2008. / "A dissertation submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Under the direction of Daniel F. Gleason. ETD. Electronic version approved: May 2008. Includes bibliographical references (p. 53-61) and appendices.

Thesis (S.T.M.)--Dallas Theological Seminary, 1993. / Includes bibliographical references (leaves [65]-70).

Thesis (Ph.D.) - Carleton University, 2006. / Includes bibliographical references (p. 128-140). Also available in electronic format on the Internet.

Thesis (Ph. D.)--Hebrew Union College-Jewish Institute of Religion, 1996. / Includes bibliographical references (p. 982-1021). Also issued in print.

Thesis (doctoral)--Universität zu Rostock.

Thesis (doctoral)--Universität Zürich.