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Full-Text Articles in Ecology and Evolutionary Biology
Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan
Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan
Doctoral Dissertations
Understanding the shape variation of the human sphenoidal sinus is important to several areas of research. This includes clinical investigation (sinus pathology and safe endoscopic endonasal surgical practice) and paranasal sinus evolution (for which there is still no consensus). Yet, the sphenoidal sinus has high morphological variation, prohibiting its quantification through traditional geometric morphometric landmarking methods. The sphenoid body, and thus also the sinus contained within, is located directly at the developmental center of the basicranium in humans, where the three cranial fossae meet at the midline, and adjacent to the three synchondroses which are the sites of cranial base …
Constraints Of The Imagination: How Phenotypes Are Shaped Through Genetics, The Environment, And Development, Michelle Gilbert
Constraints Of The Imagination: How Phenotypes Are Shaped Through Genetics, The Environment, And Development, Michelle Gilbert
Doctoral Dissertations
Phenotypic constraints are ubiquitous throughout nature, being found throughout all stages of life and at multiple different biological levels including cellular, genetic, environmental, behavioral, evolutionary, and developmental. These constraints have shaped, not only the natural world, but the way that we perceive what is possible, or impossible, an observation made clear by François Jacob in his 1977 paper “Evolution and Tinkering”. This is reflected in the literature, repeatedly, by the regular occurrence of densely packed visualization of phenotypic space that seemingly always have large areas that go unoccupied. Despite constrained regions of space being observable across countless taxa, identifying the …
Cryptic Hybridization In The Temperate Bamboos: Is Pleioblastus Simonii A Species Of Hybrid Origin?, Morgan Brown
Cryptic Hybridization In The Temperate Bamboos: Is Pleioblastus Simonii A Species Of Hybrid Origin?, Morgan Brown
Theses
Japanese river bamboo (Pleioblastus simonii, ‘medake,’‘kawadake’) is an ecologically important species of temperate bamboo native to Japan. This species is widely known and historically important in Japanese rural farm life. Based on morphological data, Japanese river bamboo is classified in Pleioblastus section Medakea (Poaceae: Bambusoideae) along with five other Japanese species, which are collectively considered to represent a phylogenetically distinct lineage. However, recent studies suggest that Japanese river bamboo may have arisen as a result of previously undetected hybridization (i.e., cryptic hybridization), while also calling into question the diversity of section Medakea. The role of hybridization in natural plant populations …
Getting To The Root Cause: The Genetic Underpinnings Of Root System Architecture And Rhizodeposition In Sorghum, Farren Smith
Getting To The Root Cause: The Genetic Underpinnings Of Root System Architecture And Rhizodeposition In Sorghum, Farren Smith
Graduate Theses, Dissertations, and Problem Reports
Plants are some of the most diverse organisms on earth, consisting of more than 350,000 different species. To understand the underlying processes that contributed to plant diversification, it is fundamental to identify the genetic and genomic components that facilitated various adaptations over evolutionary history. Most studies to date have focused on the underlying controls of above-ground traits such as grain and vegetation; however, little is known about the “hidden half” of plants. Root systems comprise half of the total plant structure and provide vital functions such as anchorage, resource acquisition, and storage of energy reserves. The execution of these key …
How The Egg Rolls: A Morphological Analysis Of Egg Shape In The Context Of Displacement Dynamics, Ian R. Hays
How The Egg Rolls: A Morphological Analysis Of Egg Shape In The Context Of Displacement Dynamics, Ian R. Hays
Theses and Dissertations
Very little is known about how morphology effects the motion, stability and the resulting viability of avian eggs. The limited research that exists focuses on the pyriform or ‘pointed’ egg shapes found in the Alcidea family. This unusual shell form is thought to suppress displacement and prevents egg loss on the cliffside nesting habitat of the Uria genera. Unfortunately, these studies never isolated or quantify the specific morphological features (elongation, asymmetry and conicality) of these pyriform eggs, which limits their applicability to other taxa and hampers a robust proof of concept. We isolated each feature as a variable, produced models …
A Characterization Of West Virginia Coyotes (Canis Latrans) Utilizing Skull Morphology, Katharina E. Scholer
A Characterization Of West Virginia Coyotes (Canis Latrans) Utilizing Skull Morphology, Katharina E. Scholer
Theses, Dissertations and Capstones
Coyotes (Canis latrans) are now found throughout North and Central America, but before European colonization were restricted to west of the Mississippi. Migration occurred in two major paths to the East; north over the Great Lakes (through Canada) and south below the Great Lakes. The location of these routes is significant because those migrating north interbred with the wolves that reside there. These hybrid animals are larger and behaviorally different from their western counterparts. It is possible to differentiate these hybrids morphologically and genetically. Hybrids are known to be located in Maine, New York, and Pennsylvania, but the interest of …
The Role Of Phenotypic Integration In Mammalian Tooth Function And Jaw Morphological Diversity, Andrew Conith
The Role Of Phenotypic Integration In Mammalian Tooth Function And Jaw Morphological Diversity, Andrew Conith
Doctoral Dissertations
Here I investigate how two major components of the mammalian feeding system, teeth and jaws, are influenced by functional, environment, and developmental factors. First, I build physical models of the molars from two early mammals, Morganucodon and Kuehneotherium, and compare their ability to process a proxy food item. Early mammals were under strong selection to reduce metabolic costs, so any savings in energy during feeding would be advantageous. I tested the ability of both mammals to process a hard and soft food item with material properties similar to that of the insects they would have likely consumed. Morganucodon was …
A Morphological And Genetic Analysis Of Forensically Important Blow Flies, From Georgia: The Genus Lucilia, Katie S. Googe
A Morphological And Genetic Analysis Of Forensically Important Blow Flies, From Georgia: The Genus Lucilia, Katie S. Googe
Honors College Theses
Identification of Blow flies (Diptera: Calliphoridae) to species is important for estimating postmortem intervals, because insect species develop at different rates. Three Blow fly species in Georgia; Lucilia coeruleiviridis, L. cuprina, and L. sericata are similar morphologically, making identification difficult. Furthermore, the status of L. cuprina is in doubt; this species may be a complex of true L. cuprina, and L. cuprina x L. sericata hybrids. The objective of this study was to survey the Georgia Blow fly community and validate the statuses of L. coeruleiviridis, L. cuprina, and L. sericata, through morphological and …
The Effects Of Locomotor Posture On Kinematics, Performance And Behavior During Obstacle Negotiation In Lizards, Jessica Self
The Effects Of Locomotor Posture On Kinematics, Performance And Behavior During Obstacle Negotiation In Lizards, Jessica Self
Electronic Theses and Dissertations
The ability to efficiently move over uneven terrain is critical for most terrestrial animals. Bipedal running is common in lizard species, however the biological advantage of a bipedal running posture remains uncertain. I examined the hypothesis that a bipedal posture is advantageous when crossing obstacles. Particularly, I determined whether kinematic adjustments differ among four focal species with contrasting body forms and ecology. I also examined how sprint speed changed when crossing obstacles with a quadrupedal versus a bipedal posture. I quantified kinematics from high-speed video (300 frames/second) of lizards running down a 3m runway both with and without the presence …
The Status Of Dwarfed Populations Of Short-Horned Lizards (Phrynosoma Hernandesi) And Great Plains Toads (Anaxyrus Cognatus) In The San Luis Valley, Colorado, Megan E. Lahti
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The San Luis Valley is a large valley formation in Colorado surrounded on either side by mountain ranges exceeding 4,267 m. Within the Valley, two of the 14 amphibian and reptile species are dwarfed: the short-horned lizard (Phrynosoma hernandesi) and the Great Plains toad (Anaxyrus cognatus). Since its initial reporting in 1968 and confirmation in 1981, no research further investigating this dwarfism has been conducted. I collected morphological measurements to determine the extent and patterns of dwarfism of both species. I then investigated the genetics of both species using mitochondrial DNA to determine whether they are …