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- All Subjects: color
- Creators: Ligon, Russell
Description
Testosterone (T) is a steroid hormone that affects behavior and reproductive traits (e.g. spermatogenesis and ornamentation) in vertebrates. In addition to long-term influences, T can rapidly increase in males following aggressive male-male encounters. Less is known how females directly influence male T and behavior, though research with humans suggests that sexually attractive females elicit a greater increase in male T and reproductive behavior than unattractive females. In birds, the influence of female attractiveness on male T and behavior is currently untested. We hypothesized that T and courtship behavior in male zebra finches would correlate with female attractiveness. We used red leg bands to make females "attractive" and green bands to make them "unattractive" (unbanded females were controls) as previous research suggests that zebra finches prefer red colors over green in mating contexts. We collected blood from males before and after "speed-dating" trials to measure changes in plasma T and analyzed male courtship behaviors from trial video recordings. The likelihood of plasma T increasing after a trial was significantly greater in males who were with red-banded females compared to control females, suggesting males may find them more attractive than green or control females. Additionally, independent of band color, males who exhibited greater T differences initiated courtship sooner and spent more time closest to females. However, courtship initiation and time spent near females were not correlated with band color. Overall, our results suggest that female attractiveness can influence male reproductive physiology, but the presence of a female may trigger male courtship behavior.
ContributorsBero-Buell, Brianna Danielle (Author) / McGraw, Kevin (Thesis director) / Deviche, Pierre (Committee member) / Ligon, Russell (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
Every color that you see in film is purposely chosen by the filmmakers. The majority of film viewers do not consciously realize the role that color plays in their movie experience. Subconsciously, viewers are deeply affected by the color choices in the film as it changes moods, tones, characters, and more. By examining color in film, filmmakers are able to create better stories, therefore having a greater effect on the audience. By becoming aware of the role of color in film, audience members become better, more involved viewers.
The following project is cut into three major parts: Color Theory in Film, An Analysis of Symbolic Color, and the Technical Applications of Color in Film. Part One gives the necessary background on color theory, light theory, color mixing, color associations, and color palettes needed to understand the rest of the project. Part Two examines color symbolism and color psychology in three films, detailing their importance to the storylines in-depth. Part Three looks at the ways filmmakers employ color during post-production, principal photography, and post-production. By looking at production design, the history of color grading, and the power of lighting and cinematography, one is able to discern the different effects color creates and how that effect is created.
The following project is cut into three major parts: Color Theory in Film, An Analysis of Symbolic Color, and the Technical Applications of Color in Film. Part One gives the necessary background on color theory, light theory, color mixing, color associations, and color palettes needed to understand the rest of the project. Part Two examines color symbolism and color psychology in three films, detailing their importance to the storylines in-depth. Part Three looks at the ways filmmakers employ color during post-production, principal photography, and post-production. By looking at production design, the history of color grading, and the power of lighting and cinematography, one is able to discern the different effects color creates and how that effect is created.
ContributorsMcholland, Megan (Author) / Nascimento, Eliciana (Thesis director) / Klucsarits, Philip (Committee member) / Dean, Herberger Institute for Design and the Arts (Contributor) / School of Art (Contributor) / School of Film, Dance and Theatre (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Sexual and social signals have long been thought to play an important role in speciation and diversity; hence, investigations of intraspecific communication may lead to important insights regarding key processes of evolution. Though we have learned much about the control, function, and evolution of animal communication by studying several very common signal types, investigating rare classes of signals may provide new information about how and why animals communicate. My dissertation research focused on rapid physiological color change, a rare signal-type used by relatively few taxa. To answer longstanding questions about this rare class of signals, I employed novel methods to measure rapid color change signals of male veiled chameleons Chamaeleo calyptratus in real-time as seen by the intended conspecific receivers, as well as the associated behaviors of signalers and receivers. In the context of agonistic male-male interactions, I found that the brightness achieved by individual males and the speed of color change were the best predictors of aggression and fighting ability. Conversely, I found that rapid skin darkening serves as a signal of submission for male chameleons, reducing aggression from winners when displayed by losers. Additionally, my research revealed that the timing of maximum skin brightness and speed of brightening were the best predictors of maximum bite force and circulating testosterone levels, respectively. Together, these results indicated that different aspects of color change can communicate information about contest strategy, physiology, and performance ability. Lastly, when I experimentally manipulated the external appearance of chameleons, I found that "dishonestly" signaling individuals (i.e. those whose behavior did not match their manipulated color) received higher aggression from unpainted opponents. The increased aggression received by dishonest signalers suggests that social costs play an important role in maintaining the honesty of rapid color change signals in veiled chameleons. Though the color change abilities of chameleons have interested humans since the time of Aristotle, little was previously known about the signal content of such changes. Documenting the behavioral contexts and information content of these signals has provided an important first step in understanding the current function, underlying control mechanisms, and evolutionary origins of this rare signal type.
ContributorsLigon, Russell (Author) / McGraw, Kevin J. (Committee member) / DeNardo, Dale F (Committee member) / Karsten, Kristopher B (Committee member) / Rutowski, Ronald L (Committee member) / Deviche, Pierre (Committee member) / Arizona State University (Publisher)
Created2015