Matching Items (4)
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- All Subjects: Metabolism
- All Subjects: Animal communication
- All Subjects: Sucker
- Creators: DeNardo, Dale F
- Resource Type: Text
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
Description
Environmental changes are occurring at an unprecedented rate, and these changes will undoubtedly lead to alterations in resource availability for many organisms. To effectively predict the implications of such changes, it is critical to better understand how organisms have adapted to coping with seasonally limited resources. The vast majority of previous work has focused on energy balance as the driver of changes in organismal physiology. While energy is clearly a vital currency, other resources can also be limited and impact physiological functions. Water is essential for life as it is the main constituent of cells, tissues, and organs. Yet, water has received little consideration for its role as a currency that impacts physiological functions. Given the importance of water to most major physiological systems, I investigated how water limitations interact with immune function, metabolism, and reproductive investment, an almost entirely unexplored area. Using multiple species and life stages, I demonstrated that dehydrated animals typically have enhanced innate immunity, regardless of whether the dehydration is a result of seasonal water constraints, water deprivation in the lab, or high physiological demand for water. My work contributed greatly to the understanding of immune function dynamics and lays a foundation for the study of hydration immunology as a component of the burgeoning field of ecoimmunology. While a large portion of my dissertation focused on the interaction between water balance and immune function, there are many other physiological processes that may be impacted by water restrictions. Accordingly, I recently expanded the understanding of how reproductive females can alter metabolic substrates to reallocate internal water during times of water scarcity, an important development in our knowledge of reproductive investments. Overall, by thoroughly evaluating implications and responses to water limitations, my dissertation, when combined previous acquired knowledge on food limitation, will enable scientists to better predict the impacts of future climate change, where, in many regions, rainfall events are forecasted to be less reliable, resulting in more frequent drought.
ContributorsBrusch, George, IV (Author) / DeNardo, Dale F (Thesis advisor) / Blattman, Joseph (Committee member) / French, Susannah (Committee member) / Sabo, John (Committee member) / Taylor, Emily (Committee member) / Arizona State University (Publisher)
Created2019
Description
Early humans adapted to eating cooked food with increased energy density and absorption of macronutrients. However, in modern times many suffer from diseases like obesity and type 2 diabetes which can result from too much energy being absorbed from food. This study measures glucose responses to a high glycemic meal with a side dish of raw or cooked vegetables. There was a slight trend for raw vegetables to have decreased postprandial blood glucose responses when compared to cooked vegetables.
ContributorsWilkins, Christine Marie (Author) / Johnston, Carol (Thesis director) / Jacobs, Mark (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor)
Created2014-05
Description
August Krogh, a 20th century Nobel Prize winner in Physiology and Medicine, once stated, "for such a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied." What developed to be known as the Krogh Principle, has become the cornerstone of bioinspired robotics. This is the realization that solutions to various multifaceted engineering problems lie in nature. With the integration of biology, physics and engineering, the classical approach in solving engineering problems has transformed. Through such an integration, the presented research will address the following engineering solution: maneuverability on and through complex granular and aquatic environments. The basilisk lizard and the octopus are the key sources of inspiration for the anticipated solution. The basilisk lizard is a highly agile reptile with the ability to easily traverse on vast, alternating, unstructured, and complex terrains (i.e. sand, mud, water). This makes them a great medium for pursuing potential solutions for robotic locomotion on such terrains. The octopus, with a nearly soft, yet muscular hydrostat body and arms, is proficient in locomotion and its complex motor functions are vast. Their versatility, "infinite" degrees of freedom, and dexterity have made them an ideal candidate for inspiration in the fields such as soft robotics. Through conducting animal experiments on the basilisk lizard and octopus, insight can be obtained on the question: how does the animal interact with complex granular and aquatic environments so effectively? Following it through by conducting systematic robotic experiments, the capabilities and limitations of the animal can be understood. Integrating the hierarchical concepts observed and learnt through animal and robotic experiments, it can be used towards designing, modeling, and developing robotic systems that will assist humanity and society on a diversified set of applications: home service, health care, public safety, transportation, logistics, structural examinations, aquatic and extraterrestrial exploration, search-and-rescue, environmental monitoring, forestry, and agriculture, just to name a few. By learning and being inspired by nature, there exist the potential to go beyond nature for the greater good of society and humanity.
ContributorsBagheri, Hosain (Author) / Marvi, Hamidreza (Thesis advisor) / Berman, Spring M (Committee member) / DeNardo, Dale F (Committee member) / Emady, Heather N (Committee member) / Lee, Hyunglae (Committee member) / Arizona State University (Publisher)
Created2020