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Reconstructing Geographic And Trophic Histories Of Fish Using Bulk And Compound-Specific Stable Isotopes From Eye Lenses, Amy A. Wallace Nov 2019

Reconstructing Geographic And Trophic Histories Of Fish Using Bulk And Compound-Specific Stable Isotopes From Eye Lenses, Amy A. Wallace

USF Tampa Graduate Theses and Dissertations

The present research examined the viability and utility of eye lenses as a source of lifetime stable-isotope records in fish. It is presented in three sections. The first section compared bulk isotopic variation (bulk analysis) within fish eye-lenses at two temporal resolutions and compared patterns obtained from left and right eyes. The first temporal resolution was lower in an attempt to expose broad-scale isotopic changes during life while reducing effort and cost. This approach did reveal lifetime patterns, but tended to miss certain life events, particularly during early life. The second resolution was higher and provided detail that was missed …


The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki Nov 2019

The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki

USF Tampa Graduate Theses and Dissertations

This dissertation explores the ecohydrology of Florida’s peculiar and poorly studied sandhill wetland and water features, particularly those located in west-central Florida. The primary research goals include: compilation and summarization of the available ecohydrologic information for features across Florida; comparison of water level and water geochemistry data between sandhill wetlands and waters and the regional aquifer to provide evidence of regional hydrologic control; and use of geophysical applications to examine the hydraulic connections between sandhill wetlands and waters and the regional aquifer.

From this research, a natural history of sandhill wetland and water ecohydrology is presented, highlighting: the differences between …


Effects Of Reservoir Conditions And Trace Co-Contaminant Gases On Geological Carbon Sequestration, Ram Kumar Nov 2019

Effects Of Reservoir Conditions And Trace Co-Contaminant Gases On Geological Carbon Sequestration, Ram Kumar

USF Tampa Graduate Theses and Dissertations

Geological carbon sequestration in a saline formation is a promising technology for large-scale carbon dioxide (CO2) mitigation. Several factors such as temperature, pressure, salinity, hydraulic conductivity, and mineralogy of a formation affect the CO2 sequestration in saline formations. These factors can vary widely depending upon the type of formation or the degree of heterogeneity within a formation. In addition to these properties of the repositories, the CO2-rich flue gas streams captured from point sources often contains small amounts of impurities such as sulfur oxides (SOx) and nitrogen oxides (NOx), which may have serious implications on the chemistry of the repositories …


Seafloor Geodesy In Shallow Water With Gps On An Anchored Spar Buoy, Surui Xie, Jason Law, Randy Russell, Timothy H. Dixon, Chad Lembke, Rocco Malservisi, Melanie Rodgers, Giovanni Iannaccone, Sergio Guardato, D. F. Naar Nov 2019

Seafloor Geodesy In Shallow Water With Gps On An Anchored Spar Buoy, Surui Xie, Jason Law, Randy Russell, Timothy H. Dixon, Chad Lembke, Rocco Malservisi, Melanie Rodgers, Giovanni Iannaccone, Sergio Guardato, D. F. Naar

School of Geosciences Faculty and Staff Publications

Measuring seafloor motion in shallow coastal water is challenging due to strong and highly variable oceanographic effects. Such measurements are potentially useful for monitoring near‐shore coastal subsidence, subsidence due to petroleum withdrawal, strain accumulation/release processes in subduction zones and submerged volcanoes, and certain freshwater applications, such as volcano deformation in caldera‐hosted lakes. We have developed a seafloor geodesy system for this environment based on an anchored spar buoy topped by high‐precision GPS. Orientation of the buoy is measured using a digital compass that provides heading, pitch, and roll information. The combined orientation and GPS tracking data are used to recover …


Boron Variation And The Subducted Sediment Component In The Volcanics From The Bifurcated Portion Of The Lesser Antilles Island Arc (Laia), Ami Margret Ngo Ward Nov 2019

Boron Variation And The Subducted Sediment Component In The Volcanics From The Bifurcated Portion Of The Lesser Antilles Island Arc (Laia), Ami Margret Ngo Ward

USF Tampa Graduate Theses and Dissertations

North of Martinique island the Lesser Antilles volcanic arc bifurcates, creating a double arc. Here volcanic activity has migrated up to 50 km westward with time, resulting in two volcanic lines that are distinct in age. The eastern line, commonly referred to as the old arc, was active from Early Eocene to Mid-Miocene (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., 1988). The western line, commonly referred to as the recent arc, has been active since the late Pliocene, ~6 Ma ago (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., …


On The Ablation Of Meteors And The Implications On Organic Delivery To Earth, Christopher Alan Mehta Oct 2019

On The Ablation Of Meteors And The Implications On Organic Delivery To Earth, Christopher Alan Mehta

USF Tampa Graduate Theses and Dissertations

The synthesis of prebiotic organic compounds is a key step in the origin of life. Sources of these materials are divided into endogenous and exogenous sources. Endogenous synthesis—occurring potentially on the surface of the Earth—includes such historic experiments as the Miller spark discharge and formose chemistry. However, one avenue for exogenous synthesis to occur is when meteors enters an atmosphere. Using principles of orbital mechanics, geology, physics, and chemistry, we study meteor ablation and the transport of organic matter to the surface of Earth. To do so, I create numerical models that simulates meteors traveling through the atmosphere of Earth …


Mattes J., 2019. Wissenskulturen Des Subterranen. Vermittler Im Spannungsfeld Zwischen Wissenschaft Und Öffentlichkeit. Ein Biographisches Lexikon. [The Culture Of Subterranean Knowledge. Mediators In The Field Of Tension Between Science And Public. A Biographical Lexicon], Monika Schöner Oct 2019

Mattes J., 2019. Wissenskulturen Des Subterranen. Vermittler Im Spannungsfeld Zwischen Wissenschaft Und Öffentlichkeit. Ein Biographisches Lexikon. [The Culture Of Subterranean Knowledge. Mediators In The Field Of Tension Between Science And Public. A Biographical Lexicon], Monika Schöner

International Journal of Speleology

No abstract provided.


The Lampenflora In Show Caves And Its Treatment: An Emerging Ecological Problem, Carlos Baquedano Estévez, Luis Moreno Merino, Almudena De La Losa Román, Juan J. Durán Valsero Oct 2019

The Lampenflora In Show Caves And Its Treatment: An Emerging Ecological Problem, Carlos Baquedano Estévez, Luis Moreno Merino, Almudena De La Losa Román, Juan J. Durán Valsero

International Journal of Speleology

The artificial lighting of caves adapted for touristic visits, leads to the appearance and propagation of a complex community of phototrophic organisms known as “lampenflora”. Formed mainly by algae and cyanobacteria, they produce the degradation of the colonized substrates and decrease the show value of the caves. This phenomenon became famous worldwide in the 1960s due to the damage caused to the paintings in the Lascaux Cave (France). Since then it has become an issue of serious concern to both managers of show caves and to the international scientific community. Over time, the problem has been approached following two complementary …


Barite Replacement Boxwork In The Frasassi Caves (Italy), Sandro Galdenzi Sep 2019

Barite Replacement Boxwork In The Frasassi Caves (Italy), Sandro Galdenzi

International Journal of Speleology

The Frasassi caves, located in the Sentino River Gorge in Ancona Province (Marche, Italy), contains boxwork in a small zone in the inner part of the cave system where it is closely associated with subaqueous corrosion produced by sulfuric acid speleogenesis. The boxwork consists of barite that replaces calcite spar-filled veins and limestone porosity and projects from the corroded cave walls. The replacement involved only the calcite that protrudes from the rock surfaces, indicating that the process took place in the cave environment, and therefore the boxwork is not simply a product of differential corrosion. I hypothesize that the boxwork …


Petrography And Provenance Of Floor Sediments From The Loutra Almopias Cave (Pella, Macedonia, Greece), Ioannis Georgiadis, Katerina Chatzopoulou, Nikolaos Kantiranis, Ioakeim Ioakeimidis, Ananias Tsirambides Sep 2019

Petrography And Provenance Of Floor Sediments From The Loutra Almopias Cave (Pella, Macedonia, Greece), Ioannis Georgiadis, Katerina Chatzopoulou, Nikolaos Kantiranis, Ioakeim Ioakeimidis, Ananias Tsirambides

International Journal of Speleology

Thirty seven floor sediment samples of Upper Pleistocene age from the Loutra Almopias Cave were collected from different beds and stratigraphic columns on the basis of their induration grade, grain distribution, and paleontological findings. Channel facies make up the bulk of the clastic sediments found in the cave passages. Slackwater facies compose the final layer of all the stratigraphic sections of the examined cave. The floor sediments are mineralogically immature, since they contain many ferromagnesian minerals, feldspars (especially plagioclase) and quartz. The extensive presence of silicate minerals means that the phyllites, gneisses, schists, ophiolitic rocks and the clastic Mariam Formation …


Genesis Of Iron And Manganese Sediments In Zoloushka Cave (Ukraine/Moldova) As Revealed By Δ13C Organic Carbon, Piotr Kotula, Viacheslav Andreychouk, Jacek Pawlyta, Leszek Marynowski, Izabela Jendrzejewska Sep 2019

Genesis Of Iron And Manganese Sediments In Zoloushka Cave (Ukraine/Moldova) As Revealed By Δ13C Organic Carbon, Piotr Kotula, Viacheslav Andreychouk, Jacek Pawlyta, Leszek Marynowski, Izabela Jendrzejewska

International Journal of Speleology

Zoloushka Cave is one of the largest maze gypsum caves in the world. Mining of the gypsum bedrock and lowering of the water level due to the pumping of groundwater led to exposure of the cave passages to vadose conditions and changed the hydrochemistry of the karst water. As a result, large quantities of Fe and Mn hydroxides were deposited in the passages. It was found that at least two groups of various organisms were involved in depositing ferrous and manganese sediments. In order to establish the mechanism of deposition, we conducted chemical analyses of the sediments and isotopic analyses …


Full Issue 48(2) Sep 2019

Full Issue 48(2)

International Journal of Speleology

No abstract provided.


Table Of Contents Sep 2019

Table Of Contents

International Journal of Speleology

No abstract provided.


Multi-Phased Hypogene Speleogenesis In A Marginal Horst Structure Of The Malé Karpaty Mountains, Slovakia, Pavel Bella, Pavel Bosák, Petr Mikysek, Juraj Littva, Helena Hercman, Jacek Pawlak Aug 2019

Multi-Phased Hypogene Speleogenesis In A Marginal Horst Structure Of The Malé Karpaty Mountains, Slovakia, Pavel Bella, Pavel Bosák, Petr Mikysek, Juraj Littva, Helena Hercman, Jacek Pawlak

International Journal of Speleology

The Plavecká jaskyňa Cave on the western fault edge of the Malé Karpaty Mountains (western Slovakia) is a result of multi-phased hypogene speleogenesis. It formed in fractured Triassic carbonates by waters ascending along the Vienna Basin Transform Fault between Malé Karpaty Mountains and Záhorská nížina Lowland (the north-eastern part of the Vienna Basin) and/or the N–S-trending faults that intersect it in the cave vicinity. Morphologically, the cave is featured by (1) phreatic chimneys, cupolas, ceiling pockets, enlarged fissures with spongework cavities, upward wall channels and upward oriented large scallops, (2) epiphreatic flat corrosion bedrock floors, feeding fissures and wall water-table …


Fluid-Mobile Trace Element Variability Of Serpentinites And Entrained Crustal Rocks Across The Mariana Forearc System, Raymond M. Johnston Aug 2019

Fluid-Mobile Trace Element Variability Of Serpentinites And Entrained Crustal Rocks Across The Mariana Forearc System, Raymond M. Johnston

USF Tampa Graduate Theses and Dissertations

In the Mariana subduction system, active serpentinite mud volcanoes are associated with the subduction of the Pacific plate beneath the Philippine plate in a non-accretionary convergent plate margin. This location offers a unique opportunity to study the subduction zone interface with little crustal contamination. The systematics of fluid-mobile trace elements (FME) (As, Cs, Rb, Sb, Tl, Pb, and Sr) in erupted serpentinite muds and entrained serpentinized ultramafic and mafic clasts can place constraints on the release of slab-derived fluids from the downgoing plate, and ultimately the pressure/temperature (P/TC°) conditions at which these fluids are mobilized.

The samples analyzed in this …


The Record‐Setting 2018 Eastern North Pacific Hurricane Season, Kimberly M. Wood, Philip J. Klotzbach, Jennifer M. Collins, Carl J. Schreck Aug 2019

The Record‐Setting 2018 Eastern North Pacific Hurricane Season, Kimberly M. Wood, Philip J. Klotzbach, Jennifer M. Collins, Carl J. Schreck

School of Geosciences Faculty and Staff Publications

The extremely active 2018 eastern North Pacific (ENP) hurricane season set records for number of hurricane days, major hurricane days, and accumulated cyclone energy (ACE). The Western Development Region (116°W–180°) was especially active, shattering its prior record for ACE set in 2015. In addition, Hawaii was impacted by Hurricane Lane in August and Tropical Storm Olivia in September. Despite above‐normal sea surface temperatures (SSTs) and below‐normal vertical wind shear in 2018, large‐scale conditions were generally less conducive for tropical cyclone (TC) formation than in 2015. However, the strong subtropical ridge in August and September of 2018 enhanced westward steering flow, …


Breakdown Mechanisms In Iron Caves. An Example From Brazil, Marcelo R. Barbosa, Allan D.F. Da Silva, Rafael G. De Paula, Georgete M. Dutra, Airton Barata, Iuri V. Brandi, Chrystophe R.P. Da Silva, Robert A. Osborne Jul 2019

Breakdown Mechanisms In Iron Caves. An Example From Brazil, Marcelo R. Barbosa, Allan D.F. Da Silva, Rafael G. De Paula, Georgete M. Dutra, Airton Barata, Iuri V. Brandi, Chrystophe R.P. Da Silva, Robert A. Osborne

International Journal of Speleology

An iron cave in the vicinity of a mine in Carajás, Brazil, was selected to be mined within an assisted elimination project, planned to control all mine advancement operations towards the cave along with a strict speleological physical monitoring. It allowed, in a pioneering way, the recording of events in the cave from the first signs of damage until to the total collapse of the cave. The project lasted four years and it was possible to identify and describe four breakdown mechanisms in iron caves: Fragment downfall, Block downfall, Controlling structure reactivation, and Open discontinuity movement. The mechanisms occurred independently …


Stable Isotope Geochemistry Of Shelled Marine Invertebrates: Wide-Ranging Applications, Nasser M. Al-Qattan Jul 2019

Stable Isotope Geochemistry Of Shelled Marine Invertebrates: Wide-Ranging Applications, Nasser M. Al-Qattan

USF Tampa Graduate Theses and Dissertations

Mollusks grow by adding discrete growth layers throughout their lifetime (i.e., accretion). More specifically, most marine mollusks precipitate their shells in oxygen isotopic equilibrium with seawater or with a constant offset from equilibrium. The stable oxygen isotope values (δ18O) of their shells are determined by the temperature and δ18O values of the surrounding water during calcification without significant vital effects. In comparison, the stable carbon isotope values (δ13C) of their shells reflect those of the dissolved inorganic carbon (δ13C- DIC) and respired carbon dioxide. Therefore, variations in the oxygen and carbon isotope …


Modeling And Assessing Lava Flow Hazards, Elisabeth Gallant Jul 2019

Modeling And Assessing Lava Flow Hazards, Elisabeth Gallant

USF Tampa Graduate Theses and Dissertations

Lava flow hazards are one of the few constant themes across the wide spectrum of volcanic research in the solar system. These dynamic hazards are controlled by the location of the eruption, the topography and material properties of the land upon which the flow spreads, and the properties of the lava (e.g., volume, temperature, and rheology). Understanding the influences on eruption location and how lava flows modify the landscape are important steps to accurately forecast volcanic hazards. Three studies are presented in this dissertation that address di˙erent aspects of modeling and assessing vent opening and lava flow hazards.

The first …


Framing Geologic Numeracy For The Purpose Of Geoscience Education: The Geoscience Quantitative Preparation Survey, Victor J. Ricchezza Jul 2019

Framing Geologic Numeracy For The Purpose Of Geoscience Education: The Geoscience Quantitative Preparation Survey, Victor J. Ricchezza

USF Tampa Graduate Theses and Dissertations

The Geoscience Quantitative Preparation Survey (GQPS) was developed to address a deficiency in the available literature regarding the competency and preparation of early-career geologists in geoscience job-related quantitative skills – namely, geologic numeracy. The final version of the GQPS included self-confidence, usage, satisfaction, and demographic sections. The GQPS was expected to produce data that would allow for an evaluation of the geologic numeracy of early-career geologists and the success of approximately 20 years of increased focus on quantitatively literate geoscience graduates.

The self-confidence section of the GQPS included quantitative methods and quantitative skills. The usage section asked whether participants used …


Morphodynamics Of Barrier-Inlet Systems In The Context Of Regional Sediment Management, With Case Studies From West-Central Florida, Usa, Tanya Beck, Ping Wang Jul 2019

Morphodynamics Of Barrier-Inlet Systems In The Context Of Regional Sediment Management, With Case Studies From West-Central Florida, Usa, Tanya Beck, Ping Wang

School of Geosciences Faculty and Staff Publications

The temporal and spatial scales controlling the morphodynamics of barrier-inlet systems are critical components of regional sediment management practice. This paper discusses regional sediment management methods employed at multiple barrier-inlet systems, with case studies from West-Central Florida. A decision-support tool is proposed for regional sediment management with discussion of its application to barrier-inlet systems. Connecting multiple barrier islands and inlets at appropriate spatio-temporal scales is critical in developing an appropriately scoped sediment management plan for a barrier-inlet system. Evaluating sediment bypassing capacity and overall inlet morphodynamics can better inform regional sand sharing along barrier-inlet coastlines; particularly where sediment resources are …


Tracking Sediment Bypassing, Geomorphological Analysis, And Regional Sediment Management At Tidal Inlets, Tanya M. Beck Jul 2019

Tracking Sediment Bypassing, Geomorphological Analysis, And Regional Sediment Management At Tidal Inlets, Tanya M. Beck

USF Tampa Graduate Theses and Dissertations

Tidal inlets on sandy shorelines separate barrier islands and serve as a conduit for transport of sand and water between embayments and oceans, seas, or other tidally influenced waterbodies. Tides and waves induce currents along the coastline that transport sediment across-shore and alongshore. Coastal managers must optimize barrier-inlet system stability while conserving limited sediment resources, and often base management decisions and engineering design upon geomorphic and numerical models that predict the morphological behavior of tidal inlets on short-to-medium timescales (years to decades). The overall goal of this study was threefold. First, to provide science-based practical guidance for regional sediment management …


Reconstruction Of Radar Images By Using Spherical Mean And Regular Radon Transforms, Ozan Pirbudak Jun 2019

Reconstruction Of Radar Images By Using Spherical Mean And Regular Radon Transforms, Ozan Pirbudak

USF Tampa Graduate Theses and Dissertations

The goal of this study is the recovery of functions and finite parametric distributions from their spherical means over spheres and designing a general formula or algorithm for the reconstruction of a function f via its spherical mean transform. The theoretical study is and supported with a numerical implementation based on radar data. In this study, we approach the reconstruction problem in two different way. The first one is to show how the reconstruction problem could be converted to a Prony-type system of equations. After solving this Prony-type system of equations, one can extract the parameters that describe the corresponding …


The Distribution And Biogeochemistry Of Subtropical Intertidal Microbial Mats, Bert D. Anderson Jun 2019

The Distribution And Biogeochemistry Of Subtropical Intertidal Microbial Mats, Bert D. Anderson

USF Tampa Graduate Theses and Dissertations

Microbial mats have played an important role in the carbon (C) and nutrient cycles since the Archean Eon and modern mats are important contributors to the biogeochemistry of intertidal wetlands. Microbial mats are flat assemblages of microbes that are currently found in many unvegetated habitats globally. Intertidal salt pans are a common habitat for microbial mats, however little is known about the distribution of microbial mats within the intertidal landscape. Understanding the spatial distribution of microbial mats is critical to developing quantitative estimates of the impacts of microbial mats on their ecosystems. We photographically measured the presence and density of …


Rethinking Map Literacy And An Analysis Of Quantitative Map Literacy, Ming Xie Jun 2019

Rethinking Map Literacy And An Analysis Of Quantitative Map Literacy, Ming Xie

USF Tampa Graduate Theses and Dissertations

Maps are increasingly being used in traditional and virtual media, and civic discourse on political, social, and environmental issues, among others, is more and more becoming influenced by them. The often-used expression of a “picture tells a 1000 words” has never been so apt in our progressively more visual world. Despite this increased role and importance of maps, map literacy, as a field of research, remains rather underdeveloped. This is especially so for thematic maps, the very type of map that is finding increasing currency in discourse. As part of this under-developed nature of map literacy, the quantitative skills used …


Determining The Impacts Of The Anthropocene Through Time-Calibrated Taphonomic Grading, Nicole Seiden, Gregory S. Herbert Jun 2019

Determining The Impacts Of The Anthropocene Through Time-Calibrated Taphonomic Grading, Nicole Seiden, Gregory S. Herbert

School of Geosciences Faculty and Staff Publications

Global biodiversity loss threatens ecosystem integrity and related services for humans, but most communities lack baseline data to assess the magnitude of change. In marine conservation, molluscan death assemblages are increasingly being used as a proxy for baseline communities, and divergence between the live and the dead is assumed to reflect human impact. A drawback to partitioning an assemblage into live and dead is that inclusion of recently dead specimens in the baseline assemblage artificially reduces differences between before and after. In this study, we address this problem by using a radiocarbon- and amino acid-calibrated taphonomic grading scale to partition …


Landscape Grain Effect In Yancheng Coastal Wetland And Its Response To Landscape Changes, Peng Tian, Luodan Cao, Jialin Li, Ruiliang Pu, Xiaoli Shi, Lijia Wang, Ruiqing Liu, Hao Xu, Chen Tong, Zijing Zhou, Shuyao Shao Jun 2019

Landscape Grain Effect In Yancheng Coastal Wetland And Its Response To Landscape Changes, Peng Tian, Luodan Cao, Jialin Li, Ruiliang Pu, Xiaoli Shi, Lijia Wang, Ruiqing Liu, Hao Xu, Chen Tong, Zijing Zhou, Shuyao Shao

School of Geosciences Faculty and Staff Publications

The landscape grain effect reflects the spatial heterogeneity of a landscape and it is used as a research core of landscape ecology. The landscape grain effect can be used to not only explore spatiotemporal variation characteristics of a landscape pattern, but also to disclose variation laws of ecological structures and functions of landscapes. In this study, the sensitivity of landscape pattern indexes to grain sizes 50–1000 m was studied based on landscape data in Yancheng Coastal Wetland acquired in 1991, 2000, 2008, and 2017. Response of the grain effect to landscape changes was analyzed and an optimal grain size for …


Morphological And Mineralogical Evidence For Ancient Bat Presence In Cova Des Pas De Vallgornera (Llucmajor, Mallorca, Western Mediterranean), Antoni Merino, Joan J. Fornós, Antoni Mulet, Joaquín Ginés May 2019

Morphological And Mineralogical Evidence For Ancient Bat Presence In Cova Des Pas De Vallgornera (Llucmajor, Mallorca, Western Mediterranean), Antoni Merino, Joan J. Fornós, Antoni Mulet, Joaquín Ginés

International Journal of Speleology

Cova des Pas de Vallgornera is a unique karst cave located at the Llucmajor coastal platform that stands out not only because of its length, more than 78 km, but also for its particular morphological suite, richness and variety of speleothems and mineral infillings. Although the mineralogy of speleothems and minerals related to hypogene morphologies has been studied and described, the existence of minerals derived from guano deposits was still poorly investigated. The cave hosted bat colonies until the collapse of its natural entrances, circa 2.4 My ago, since then until its discovery in 1968, the cave remained sealed. These …


The Multifactorial Nature Of Beak And Skull Shape Evolution In Parrots And Cockatoos (Psittaciformes), Jen A. Bright, Jesús Marugán-Lobón, Emily J. Rayfield, Samuel N. Cobb May 2019

The Multifactorial Nature Of Beak And Skull Shape Evolution In Parrots And Cockatoos (Psittaciformes), Jen A. Bright, Jesús Marugán-Lobón, Emily J. Rayfield, Samuel N. Cobb

School of Geosciences Faculty and Staff Publications

Background: The Psittaciformes (parrots and cockatoos) are characterised by their large beaks, and are renowned for their ability to produce high bite forces. These birds also possess a suite of modifications to their cranial architecture interpreted to be adaptations for feeding on mechanically resistant foods, yet the relationship between cranial morphology and diet has never been explicitly tested. Here, we provide a three-dimensional geometric morphometric analysis of the developmental and biomechanical factors that may be influencing the evolution of psittaciformes’ distinctive cranial morphologies.

Results: Contrary to our own predictions, we find that dietary preferences for more- or less- mechanically resistant …


Documenting Evolution: Comparing And Contrasting Late Mesozoic And Late Cenozoic Molluscan Patterns, Joshua Slattery Apr 2019

Documenting Evolution: Comparing And Contrasting Late Mesozoic And Late Cenozoic Molluscan Patterns, Joshua Slattery

USF Tampa Graduate Theses and Dissertations

Despite major advances, evolutionary theory still has numerous shortcomings in terms of fully understanding the controls on speciation and diversification. A major factor limiting our knowledge is how biology and paleobiology view speciation from separate micro- and macro-evolutionary perspectives, respectively. Biologists typically examine microevolutionary changes within species from various biogeographic, behavioral, morphological, and genetic perspectives, which contrasts to the macroevolutionary approach of most paleobiologists, who have examined the same phenomena at larger scales but with the standpoint of time, have also concentrated on aspects of global or regional diversification (e.g., richness, origination rates, and extinction rates) over the long-term. Noticeably …