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The interploidy hybridization barrier in Zea Mays L.
(University of Missouri--Columbia, 2006)
development: 1) dosage of regulators to target loci is important for normal endosperm development; 2) evaluation of spontaneous central cell development as a cause of defective kernels in lines that induce high frequencies of haploid embryos; 3) examination...
Mechanisms of photoreceptor mediated responses in photomorphogenesis and phototropism
(University of Missouri--Columbia, 2018)
of elucidating the effect that domestication has had on early light responses. Our study indicates that G. max exhibits growth in darkness that is more characteristic of growth in light. This finding suggests that domestication has resulted in a crop species...
Age effects on reproductive behavior in the treehopper umbonia crassiscornis (Hemipera: membracidae)
(University of Missouri--Columbia, 2007)
In many animal species females select mates based on male age. This choice is often linked to the reproductive benefits females derive. Age-based choice is also influenced by variation in the ability of males to find and ...
Effects of forest fragmentation on reproductive effort and productivity of Indigo buntings (Passerina cyanea)
(University of Missouri--Columbia, 2005)
Forest fragmentation creates edge habitat that attracts nest predators that lower reproductive success and force birds to renest. To determine if predation-induced renesting causes a decline in condition of females and reduces productivity...
Beyond the edge : riparian habitat use and forest management effects on stream salamanders in the southern Appalachian mountains
(University of Missouri--Columbia, 2007)
on the effects of logging on amphibians that require streams for reproduction. In order to mitigate the impacts of habitat alteration on stream amphibians, it is necessary to have a clear understanding of the role abiotic and biotic factors play in determining...
Brassicales to Brassica : integrating phylogenomics and population genomics
(University of Missouri--Columbia, 2020)
is notable for many whole-genome duplication (WGD) events, including one at the base of the family. The sister family to the Brassicaceae, the Cleomaceae, is also known to have a WGD event; however, it has never been placed within the family. Previous studies...
The role of terrrestrial habitat in the population dynamics and conservation of pond-breeding amphibians
(University of Missouri--Columbia, 2007)
to determine microclimate and thereby influence amphibian survival. Returning to the model building process, I used the results of my field experiments to develop a demographic model designed to evaluate the potential effects of forestry practices on wood frog...
Effects of prescribed fire and timber harvest on terrestrial salamander abundance, behavior, and microhabitat use
(University of Missouri--Columbia, 2014)
The goal of my dissertation was to assess how terrestrial salamanders respond to two common forest management practices -- prescribed fire and timber harvest. Previous studies have reported that timber harvest adversely affects terrestrial...
Flipping the switch : regulation of proliferation and differentiation in adult muscle stem cells
(University of Missouri--Columbia, 2011)
of skeletal muscle is exhausted. The potential of stem cells in regenerative medicine lies in the ability to remove them from their natural niche, inducing them to proliferate in culture and placing functional cells back into a tissue environment. In order...
Behavioral choice and demographic consequences of wood frog habitat selection in response to land use
(University of Missouri--Columbia, 2007)
Land use is a pervasive form of disturbance affecting natural systems on Earth. My dissertation research is set within the context of a large scale project referred to as Land-use Effects on Amphibian Populations (LEAP), where researchers in Maine...
Effects of riparian buffer width on stream salamander populations in the southern Appalachian Mountains
(University of Missouri--Columbia, 2008)
salamanders were significantly less abundant. It is unlikely that salamanders will persist or thrive for more than a season or two in logged forests due to a significant deterioration in body condition of Ocoee salamanders in logged riparian areas. My results...
Seasonality and elevational migration in an Andean bird community
(University of Missouri--Columbia, 2010)
elevational gradients, known as altitudinal or elevational migration. Here I provide the first community-level assessment of avian elevational migration in South America. I used point counts, mist netting, focal observations of a mid-elevation mixed species...
Centromere function and evolution in maize (Zea mays)
(University of Missouri--Columbia, 2006)
A dispensable supernumerary chromosome present in maize, the B chromosome, was the focus of many centromere studies. First, I examine the variation in copy number of centromeric elements and other repeats among different maize lines. Then, I...
Dissecting the genetic basis of learning, memory, and thermal tolerance in a multi-parental population of fruit flies
(University of Missouri--Columbia, 2021)
to rapidly warming temperatures because their body temperature reflects that of their surroundings. Along with physiological mechanisms, these animals have also adapted cognitive practices, such as learning and memory, which help them escape extreme...
Establishing a foundation for large DNA transfer to artificial minichromosomes and B insert platforms in maize
(University of Missouri--Columbia, 2019)
. Additionally, BiBAC targeting to a location outside the native chromosomal sets, such as an artificial minichromosome or B chromosome platform, would enable researchers to stack traits without disrupting endogenous sequences....
A multi-scale investigation of ecologically relevant effects of agricultural runoff on amphibians
(University of Missouri--Columbia, 2008)
that contaminants common in agricultural runoff have the potential to cause mortality, immunosuppression, or reproductive abnormalities in amphibians, we have a very poor understanding of how exposure to agricultural runoff may affect amphibian population...
Characterizing territoriality and the mechanisms that mediate it in female Anolis gundlachi lizards
(University of Missouri--Columbia, 2019)
Territoriality is a suite of behaviors through which animals secure access to particular areas or resources. It is prevalent across animal groups and has the potential to exert substantial influence on fitness by mediating how individuals...
Conservation genetics of conflict in the Asian elephant, Elephas maximus
(University of Missouri--Columbia, 2021)
and elephants, research increasingly relies on noninvasive monitoring combined with a diverse assemblage of genetic tools. This dissertation uses conservation genetics to evaluate major conflict and conservation issues for Asian elephants. The first study...
Coupling, membrane conductance, and ion channel mRNA profiles in the establishment and maintenance of network activity in the crustacean cardiac ganglion
(University of Missouri--Columbia, 2021)
necessary to respond to altered demands or perturbations. Studying the mechanisms which confer these properties requires a well characterized system with a known network topology and identifiable neurons that are amenable to both electrophysiological...
Behavioral endocrinology of female gray treefrogs, Hyla versicolor, in response to acoustic stimulation
(University of Missouri--Columbia, 2008)
Particularly in organisms with a limited breeding period, females must rely on both external and physiological cues to regulate the phenology of reproduction and behavior. I investigated the relationship between male acoustic signals...