Thesis (Ph. D.)--University of California, San Diego, 1997. / Vita. Includes bibliographical references (leaves 122-130).

No description available.

No description available.

The peacock (Pavo cristatus) has long been considered the quintessential example of a sexually selected animal, and in the last two decades, peafowl have provided widely-cited evidence for female mate choice as well as the genetic benefits of mate preferences for ornamented males. However, previous studies have failed to reach a consensus with respect to the importance of various signaling modalities in peafowl courtship. In this thesis, I repeat two previous studies of peacock train morphology and I describe the use of light by males during their courtship displays, to clarify the role of visual signaling. I confirm previous reports that removing a large number of eyespots decreases male mating success, yet I find substantial variation in mating success among normal males that cannot be explained by eyespot number. I show that these two apparently conflicting results are not contradictory, since the removal treatment modifies males beyond the normal range of eyespot number. Next, I describe the two display behaviours used by males during courtship. When males perform their pre-copulatory “train-rattling” display, they are oriented at about 45° relative to the sun on average, with females directly in front. This directional pattern suggests that train-rattling is involved in the communication of a visual signal. The “wing-shaking” display, on the other hand, is performed with females positioned behind males, and is always elicited when a model female is positioned on the shaded side of a male. The wing-shaking display may therefore allow males to control female viewing geometry. These results indicate that mate choice in peafowl is complex, and that visual signaling is important despite recent claims to the contrary. Females may avoid males missing a large number of eyespots via a threshold-based mechanism, while choosing among full-trained males based on some other (possibly visual) cue. / Thesis (Master, Biology) -- Queen's University, 2008-09-12 16:29:20.772

A three-part study of the vocal and visual cues important for species recognition in six species of Darwin's Finches (Geospiza) in the Galapagos is presented. Part I quantifies structure and species-specificity of advertising song. Part II describes experiments on song function and recognition. Part III examines the role of morphology in mate recognition and reproductive isolation. Geospiza song is variable and lacks species-specificity, due to intrapopulation song polymorphism, dialect divergence, song parallelism and interspecific song overlap. Song functions in conspecific territorial communication. Much intraspecific song variation apparently has little functional significance, although vocal confusion between syntopic G. fuliginosa and G. fortis may exist. Visual recognition involves morphological (non-plumage) stimuli of both head and body. Male recognition of potential mates functions in reproductive isolation, and character displacement in recognition ability occurs. Visual cues appear to override vocal ones in short-range communication. Lack's (1945) hypothesis that Geospiza use characters specialized for feeding as mate identification cues is confirmed. Low interspecific song divergence is probably related to the evolution of visual species recognition.

Species recognition of four species of salamanders, Ambystoma, tigrinum, A. maculatum, A. opacum, and A. tremblavi, was studied in a series of investigations performed from September 9, 1984 to October 29, 1984. The purpose of the study was to determine if vision is a component in interspecies recognition in these salamanders and, if so, to determine what specific sign stimuli are effective.A total of 23 individual salamanders were tested in three experimental situations involving choices between live conspecific and heterospecific salamanders, live conspecifics and heterospecifics where no olfactory cues were available, and between different models, varying either in pattern composition or ground color.In the preliminary tests, all four species of salamander preferred their conspecifics. In the live animal tests only the tiger salamanders preferred their conspecifics. In the model tests only the tiger salamanders showed a preference for one of the models, preferring the supernormal to the natural model.

Thesis (Ph.D.)--University of Delaware, 2007. / Principal faculty advisor: Roland R. Roth, Dept. of Entomology & Wildlife Ecology. Includes bibliographical references.

Thesis (Ph. D.)--University of California, San Diego, 1998. / Vita. Includes bibliographical references (leaves 126-134).

Thesis (Ph.D.) -- Australian National University, 2007.

Thesis (M.S.)--Bowling Green State University, 2006. / Document formatted into pages; contains vi, 39 p. : ill. Includes bibliographical references.