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Distribution And Population Dynamics Of Ungulates In The Mongolian Gobi, Buuveibaatar Bayarbaatar
Distribution And Population Dynamics Of Ungulates In The Mongolian Gobi, Buuveibaatar Bayarbaatar
Doctoral Dissertations
The Mongolian Gobi is one of the most spectacular and important regions in Central Asia, comprising the largest area of intact grassland in the world. In recent years, a growing human population, expanding exploitation of natural resources, and the development of infrastructure in the region place increasing pressure on these species and their habitats. This dissertation has focused on three species of ungulates such as Mongolian saiga (Saiga tatarica mongolica) in western Mongolia, and Asiatic wild ass (Equus hemionus), and goitered gazelle (Gazella subgutturosa) in Southern Gobi. The study on endangered saiga antelope in …
Reflexivity: A First Demonstration, Melissa Jane Swisher
Reflexivity: A First Demonstration, Melissa Jane Swisher
Open Access Dissertations
Currently, the emergent relation of reflexivity after training a set of baseline relations has not been demonstrated with any animal—human or nonhuman. True reflexivity can only be demonstrated if no identity (i.e., physically matching stimulus) relations are trained. In six experiments, the emergence of reflexivity and its opposite, anti-reflexivity, were explored. Pigeons received concurrent successive matching training on two or three arbitrary tasks: AB hue-form and BC form-hue (and AC hue-hue) matching. Once they had acquired these tasks, they were tested for BB (form-form) reflexivity or BB’ (form-form) anti-reflexivity matching. Most (10 of 13) pigeons that received three arbitrary tasks …
Evolvability Of The Skull: A Study Of Genetic Basis And Integration In The Teleost Craniofacial Skeleton, Yinan Hu
Doctoral Dissertations
As the field of evolutionary biology pivots away from a gene-centric view of how adaptive evolution proceeds, renewed emphasis is placed on the origin of phenotypic variation. Understanding the developmental processes that underlie the production of novel traits, and how they might influence evolvability, is considered a primary goal in the on-going “extended evolutionary synthesis”. The following dissertation explores these questions in the context of adaptive radiations in fish, with a focus on morphological variation in the craniofacial skeleton. Specifically, the first chapter investigates the genetic and developmental basis of shape (co-)variation in the feeding apparatus of African cichlid fishes, …
Evolution Of Vernalization And Photoperiod-Regulated Genetic Networks In The Grass Subfamily Pooideae, Meghan Mckeown
Evolution Of Vernalization And Photoperiod-Regulated Genetic Networks In The Grass Subfamily Pooideae, Meghan Mckeown
Graduate College Dissertations and Theses
Flowering time is a carefully regulated trait that integrates cues from temperature and photoperiod to coordinate flowering at favorable times of the year. This dissertation aims to understand the evolution of genetic architecture that facilitated the transition of Pooideae, a subfamily of grass, from the tropics to the temperate northern hemisphere approximately 50 million years ago. Two traits hypothesized to have facilitated this evolutionary shift are the use of long-term low-temperature (vernalization) to ready plants for flowering, and long-day photoperiods to induce flowering. In chapter one I review literature on the regulation of grass flowering by vernalization and photoperiod, and …