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Chemical Investigation Of Antarctic Marine Organisms & Their Role In Modern Drug Discovery, Jacqueline Lee Fries Feb 2016

Chemical Investigation Of Antarctic Marine Organisms & Their Role In Modern Drug Discovery, Jacqueline Lee Fries

USF Tampa Graduate Theses and Dissertations

The chemicals produced by biological systems, whether proteins, peptides, or terpenes, will always provide an intriguing topic for researchers. Invisibly controlling every aspect of nature, these molecules are responsible for life, evolution, and death. Specifically, here is described the secondary metabolites produced by Antarctic marine organisms as well as others, and how they are used to defend or attract other animals while potentially providing health benefits to mankind. This is done through collection, extraction, and separation of individual specimens. The respective mixtures of compounds after isolation are then analyzed via spectroscopic methods such as nuclear magnetic resonance spectroscopy, mass spectrometry, …


Bioeconomic Evaluation Of Commercial-Scale Stock Enhancement In Abalone, Anthony M. Hart, Lachlan W.S. Strain Feb 2016

Bioeconomic Evaluation Of Commercial-Scale Stock Enhancement In Abalone, Anthony M. Hart, Lachlan W.S. Strain

Fisheries Research Reports

The evaluation of commercial-scale stock enhancement was undertaken to determine its viability in the Western Australian Greenlip Abalone fishery. The key outcome of the project is that commercial-scale abalone stock enhancement is environmentally and economically achievable. The bioeconomic analysis revealed significant economic potential of a stock enhancement program for Australian Haliotis laevigata fisheries.


Would Ecology Fail The Repeatability Test?, Stefan A. Schnitzer, Walter P. Carson Feb 2016

Would Ecology Fail The Repeatability Test?, Stefan A. Schnitzer, Walter P. Carson

Biological Sciences Faculty Research and Publications

No abstract provided.


Analysis Of Alternative Storage Conditions For Dna Recovery From Field Samples, Alison Schutt, Emily Stricklin, Britta Ten Haken, Joseph Tolsma, Laurie Furlong, Sara S. Tolsma Jan 2016

Analysis Of Alternative Storage Conditions For Dna Recovery From Field Samples, Alison Schutt, Emily Stricklin, Britta Ten Haken, Joseph Tolsma, Laurie Furlong, Sara S. Tolsma

Northwestern Review

As ecologists increasingly employ molecular methods, they find that tried and true preservation solutions (e.g. ethanol or formalin) may not be optimal when samples are targeted for genetic analyses. Before traveling to remote sample sites, researchers need to consider which preservation methods are likely to yield the largest quantity and highest quality of DNA based on their travel times and field conditions. They also need to consider whether they will have access to preservatives at remote sites and whether those preservatives can be safely transported. To determine which preservation methods would most reliably preserve tissue for genetic analysis under a …


A New Species Of Euscorpius Thorell, 1876 From Peloponnese, Greece (Scorpiones: Euscorpiidae, Gioele Tropea, Victor Fet, Aristeidis Parmakelis, Panayiota Kotsakiozi, Iasmi Stathi Jan 2016

A New Species Of Euscorpius Thorell, 1876 From Peloponnese, Greece (Scorpiones: Euscorpiidae, Gioele Tropea, Victor Fet, Aristeidis Parmakelis, Panayiota Kotsakiozi, Iasmi Stathi

Euscorpius

A new scorpion species, Euscorpius (Euscorpius) erymanthius sp. n., is described from Peloponnese, Greece (Erymanthos Mts.), based on genetic and morphological evidence. It is characterized by small size, light brown to reddish color, and a standard trichobothrial pattern (Pv = 8–9, et = 7–6, em = 4 and eb = 4). In a phylogeny based on multiple DNA markers, the new species groups close with E. corcyraeus Tropea et Rossi, 2012 from Corfu (Kerkyra) Island.


On Two Syntopic Species Of Euscorpius Thorell, 1876 (Scorpiones: Euscorpiidae) In And Nearby San Marco Fortress (Veneto, Italy): A Preliminary Investigation, Marco Colombo Jan 2016

On Two Syntopic Species Of Euscorpius Thorell, 1876 (Scorpiones: Euscorpiidae) In And Nearby San Marco Fortress (Veneto, Italy): A Preliminary Investigation, Marco Colombo

Euscorpius

The author found syntopic specimens of Euscorpius italicus and E. tergestinus inside and nearby an abandoned fortress in Verona Province, Veneto, Italy. This discovery highlights a possibility of coexistence of congeneric species not only in the same territory, as already observed, but also in the same habitat and microhabitat, bringing some interesting questions about interspecific competition within the genus Euscorpius.


The Population Structure Of Mesobuthus Gibbosus (Scorpiones: Buthidae) On Koufonisi Island (Central Aegean Archipelago, Greece), Dimitris Kaltsas, Moysis Mylonas Jan 2016

The Population Structure Of Mesobuthus Gibbosus (Scorpiones: Buthidae) On Koufonisi Island (Central Aegean Archipelago, Greece), Dimitris Kaltsas, Moysis Mylonas

Euscorpius

The population structure of Mesobuthus gibbosus was studied over 261 night-hours of sampling during 29 consecutive nights on Koufonisi Island (central Aegean Archipelago, Greece) using the capture-recapture method. The studied population proved to be the densest of all studied scorpion populations in chaparral or intertidal habitats of Mediterranean type ecosystems and even comparable to some populations of desert scorpion species. The negative influence of moon phase on the general activity of the species and synchronization in parturition were the main factors that caused the fluctuations in population density and therefore in the percentage of active scorpions.


Road-Edge Effects On Herpetofauna In A Lowland Amazonian Rainforest, Ross J. Maynard, Nathalie C. Aall, Daniel Saenz, Paul S. Hamilton, Matthew Kwiatkowski Jan 2016

Road-Edge Effects On Herpetofauna In A Lowland Amazonian Rainforest, Ross J. Maynard, Nathalie C. Aall, Daniel Saenz, Paul S. Hamilton, Matthew Kwiatkowski

Faculty Publications

The impact of roads on the flora and fauna of Neotropical rainforest is perhaps the single biggest driver of habitat modification and population declines in these ecosystems. We investigated the road-edge effect of a low-use dirt road on amphibian and reptile abundance, diversity, and composition within adjacent lowland Amazonian rainforest at San José de Payamino, Ecuador. The road has been closed to vehicle traffic since its construction in 2010. Thus, effects from vehicle mortality, vehicle-related pollution, and road noise were not confounding factors. Herpetofauna were surveyed using both visual encounter surveys and drift fences with pitfall and funnel traps at …


Bird Communities Of Different Woody Vegetation Types From The Niraj Valley, Romania, Erzsébet Domokos, József Domokos Jan 2016

Bird Communities Of Different Woody Vegetation Types From The Niraj Valley, Romania, Erzsébet Domokos, József Domokos

Turkish Journal of Zoology

In this paper, the bird assemblages of different woody vegetation types are presented in a human-modified Eastern European landscape. The studied territory is part of a Special Protection Area for bird species. The following sampling areas were included in the study: hornbeam-beech, oak-hornbeam, and sessile oak forests; thickets of willow; forests of white willow; scrubs of blackthorn and hawthorn; and orchards. Birds were grouped in a community typical of deciduous forests and in another community typical of coppices and scrubs. Bird species number, alpha diversity, and abundance were significantly higher in the Salici-Populetum association and in orchards than in the …


Maxent Modeling For Predicting Potential Distribution Of Goitered Gazelle In Central Iran: The Effect Of Extent And Grain Size On Performance Of The Model, Rasoul Khosravi, Mahmoud Reza Hemami, Mansoureh Malekian, Alan Flint, Lorraine Flint Jan 2016

Maxent Modeling For Predicting Potential Distribution Of Goitered Gazelle In Central Iran: The Effect Of Extent And Grain Size On Performance Of The Model, Rasoul Khosravi, Mahmoud Reza Hemami, Mansoureh Malekian, Alan Flint, Lorraine Flint

Turkish Journal of Zoology

The spatial scale of environmental layers is an important factor to consider in developing an understanding of ecological processes. This study employed Maxent modeling to investigate the geographic distribution of goitered gazelle, Gazella subgutturosa (Güldenstädt, 1780), in central Iran using uncorrelated variables at a spatial resolution of 250 m. We used spatial downscaling to downscale WorldClim data to 250-m resolution. We evaluated the sensitivity of the model to different grain and extent sizes from 250 m to 3 km. We compared the performance of the model at different scales using suitability indexes (AUC) and predicted habitat areas. Two models performed …


White-Tailed Deer (Odocoileus Virginianus) Subsidize Gray Wolves (Canis Lupus) During A Moose (Alces Americanus) Decline: A Case Of Apparent Competition?, Shannon M. Barber-Meyer, L. David Mech Jan 2016

White-Tailed Deer (Odocoileus Virginianus) Subsidize Gray Wolves (Canis Lupus) During A Moose (Alces Americanus) Decline: A Case Of Apparent Competition?, Shannon M. Barber-Meyer, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Moose (Alces americanus) in northeastern Minnesota have declined by 55% since 2006. Although the cause is unresolved, some studies have suggested that Gray Wolves (Canis lupus) contributed to the decline. After the Moose decline, wolves could either decline or switch prey. To determine which occurred in our study area, we compared winter wolf counts and summer diet before and after the Moose decline. While wolf numbers in our study area nearly doubled from 23 in winter 2002 to an average of 41 during winters 2011–2013, calf:cow ratios (the number of calves per cow observed during winter …


Patuxent’S Long-Term Research On Wolves, L. David Mech Jan 2016

Patuxent’S Long-Term Research On Wolves, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species.

Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota.

Endangered Species Act protection of the wolf fostered its quick …


A Comparative Study Of The Flora And Soils Of Great Duck And Little Duck Islands, Maine, Usa, Luka Negoita, Matthew Dickinson, Glen Mittelhauser, Nishanta Rajakaruna Jan 2016

A Comparative Study Of The Flora And Soils Of Great Duck And Little Duck Islands, Maine, Usa, Luka Negoita, Matthew Dickinson, Glen Mittelhauser, Nishanta Rajakaruna

Faculty Publications, Biological Sciences

Strong environmental gradients and varied land-use practices have generated a mosaic of habitats harboring distinct plant communities on islands on the coast of Maine. Botanical studies of Maine's islands, however, are generally limited in number and scope. Baseline studies of Maine's islands are necessary for assessing vegetation dynamics and changes in habitat conditions in relation to environmental impacts imposed by climate change, rising sea levels, invasive species, pests and pathogens, introduced herbivores, and human disturbance. We conducted a survey of the vascular plants and soils of forest, field, and ocean-side communities of Great Duck and Little Duck Islands, ME. These …


The Biology Of Metamorphosis Insectorum Surinamensium, Kay Etheridge Jan 2016

The Biology Of Metamorphosis Insectorum Surinamensium, Kay Etheridge

Biology Faculty Publications

Book Description: This facsimile of one of the most beautiful books of natural history ever created contains sixty magnificent illustrations showing exotic insects, with the original descriptions. The reissue is the same size as the original and is enriched with an illustrated introduction about the life, work and significance of Maria Sibylla Merian, and a new scientific description of all the insects, animals and plants.

The life and work of this German woman who moved to the Netherlands has been the subject of international research by botanists, entomologists and historians concerned with the history of science, art, religion and economics. …


Journal Of The Arkansas Academy Of Science - Volume 70 2016, Academy Editors Jan 2016

Journal Of The Arkansas Academy Of Science - Volume 70 2016, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


03. Population Demographics Of The Loggerhead Shrike: Insights Into The Species Decline From A Long-Term Study In The Midewin National Tallgrass Prairie, Amy A. Chabot, Fran Harty, James Herkert, William Glass Jan 2016

03. Population Demographics Of The Loggerhead Shrike: Insights Into The Species Decline From A Long-Term Study In The Midewin National Tallgrass Prairie, Amy A. Chabot, Fran Harty, James Herkert, William Glass

North American Prairie Conference Proceedings

We monitored a breeding population of loggerhead shrikes (Lanius ludovicianus) in the Midewin National Tallgrass Prairie from 2005 to 2016. Demographic data were compiled annually, including information on population size, age structure, and reproductive success. We banded adult shrikes, with some additional effort focused on nestlings (2005–2007) and independent hatch-year birds (2014–2016). We measured return rate as the number of birds that were previously banded. Site reuse rates were quantified as the use of a breeding territory in multiple years. Site fidelity, the use of a site by the same male or female in consecutive years, and dispersal distance of …


The Spatial Distribution Of Terrestrial Stable Carbon Isotopes In North America, And The Impacts Of Spatial And Temporal Resolution On Static Ecological Models, Sydney M. Firmin Jan 2016

The Spatial Distribution Of Terrestrial Stable Carbon Isotopes In North America, And The Impacts Of Spatial And Temporal Resolution On Static Ecological Models, Sydney M. Firmin

Electronic Theses and Dissertations

Due to the unique spatial and temporal characteristics of ecological phenomena, the extent and grain size of spatial data sets essentially filter the observations. This thesis examines the impacts of temporal and spatial resolution on the modeling of terrestrial stable carbon isotopic landscapes (isoscapes). I model the distribution of leaf stable carbon isotope composition (delta13C) for the continent of North America at multiple temporal and spatial resolutions. I generate each delta13C isoscape variation by first predicting the relative abundance of C3/C4 vegetation cover using monthly climate grids, crop distribution/type grids, and remote sensing data of plant …


Serum Chemistry, Blood Gas, And Physiological Measures Of Sandhill Cranes Sedated With Alpha-Chloralose, Richard R. Sim, Barry K. Hartup Jan 2016

Serum Chemistry, Blood Gas, And Physiological Measures Of Sandhill Cranes Sedated With Alpha-Chloralose, Richard R. Sim, Barry K. Hartup

Proceedings of the North American Crane Workshop

Capture techniques that lessen handling stress may also lessen pathologic influences on physiologic measures, improving the validity of these measures for use in individual health assessment of freeranging wildlife. Since 1990, the International Crane Foundation (ICF) has successfully used chemical immobilization with alpha-chloralose (AC; C6H11Cl3O6), a chloral derivative of glucose, to facilitate captures of sandhill cranes (Grus canadensis tabida) for ecological studies (Hayes et al. 2003). Although this chemical has been used orally for the immobilization of many species, the physiologic effects of AC are not well understood in cranes. …


Distribution, Densities, And Ecology Of Siberian Cranes In The Khroma River Region Of Northern Yakutia In Northeastern Russia, Inga P. Bysykatova, Gary L. Krapu, Nicolai I. Germogenov, Deborah A. Buhl Jan 2016

Distribution, Densities, And Ecology Of Siberian Cranes In The Khroma River Region Of Northern Yakutia In Northeastern Russia, Inga P. Bysykatova, Gary L. Krapu, Nicolai I. Germogenov, Deborah A. Buhl

Proceedings of the North American Crane Workshop

The Siberian crane (Grus leucogeranus) is the third rarest crane species in the world with a breeding range now centered on 3 core areas and a buffer zone in the arctic of northern Yakutia in northeastern Russia. During 16 July-2 August 2009, we undertook ground surveys within the Khroma River core breeding area, surrounding buffer zone, and lands lying to the west of the known breeding range to estimate densities and determine habitat use and social status of Siberian cranes. A total of 142 Siberian cranes were sighted (including 55 pairs) at 54 locations with 32 cranes (including 13 pairs) …


The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope Jan 2016

The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reservoirs can be dynamic systems, often prone to unpredictable and extreme waterlevel fluctuations, and can be environments where survival is difficult for zooplankton and larval fish. Although numerous studies have examined the effects of extreme reservoir drawdown on water quality, few have examined extreme drawdown on both abiotic and biotic characteristics. A fissure in the dam at Red Willow Reservoir in southwest Nebraska necessitated an extreme drawdown; the water level was lowered more than 6 m during a two-month period, reducing reservoir volume by 76%. During the subsequent low-water period (i.e., post-drawdown), spring sampling (April-June) showed dissolved oxygen concentration was …


Characterization Of Mechanisms That Mediate Cancer Metastatic Colonization, Alexander Huan Nguyen Jan 2016

Characterization Of Mechanisms That Mediate Cancer Metastatic Colonization, Alexander Huan Nguyen

Student Theses and Dissertations

Metastatic disease is the major cause of death in all solid tumor cancers. Current therapeutic strategies fail to target metastasis as the genes and mechanisms that regulate this process remain poorly understood. Metastatic colonization is the final step of the metastatic cascade whereby cancer cells form a tumor at a distant site. This final step is the culmination of clonal evolution of cancer populations that results in a highly aggressive population with enhanced metastatic capacity and often presents clinically as numerous inoperable tumor nodules that lead to mortality. Characterization of the mechanisms that govern metastatic colonization at cellular and molecular …


Bibliographia Phytosociologica Et Floristica Mongolia: Pars Iv, Werner Hilbig Jan 2016

Bibliographia Phytosociologica Et Floristica Mongolia: Pars Iv, Werner Hilbig

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In Ergänzung zu den bisherigen drei Teilen der Bibliographie vegetationskundlicher, vegetationsökologischer, floristischer und pflanzengeographischer Arbeiten über die Mongolei wird in dieser Arbeit Teil IV der Bibliographie vorgelegt. Er umfasst im Wesentlichen den Zeitraum 2007 bis 2014. Auch Publikationen zur Vegetationsgeschichte und zum botanischen Naturschutz werden berücksichtigt.

English summary:

In addition to the hitherto existing three parts of the bibliography of geobotanical, ecological, floristic and plant-geographical papers on Mongolia the part IV of the bibliography is given. It comprises in the main point the period from 2007 until 2014. In addition, publications on vegetation history and botanical nature protection are considered.


Special Topic: Wildlife And Wing Energy: Are They Compatible? Introduction, Michael Hutchins, Bruce D. Leopold Jan 2016

Special Topic: Wildlife And Wing Energy: Are They Compatible? Introduction, Michael Hutchins, Bruce D. Leopold

Human–Wildlife Interactions

No abstract provided.


Changes In Wetland Conditions And Wetland Plant Communities In The Prairie Pothole Region After 50 Years, Ryann Cressey Jan 2016

Changes In Wetland Conditions And Wetland Plant Communities In The Prairie Pothole Region After 50 Years, Ryann Cressey

Electronic Theses and Dissertations

Wetlands in Stutsman County, North Dakota were revisited after 50 years to assess changes in wetland conditions and plant communities within wetland zones in the Prairie Pothole Region. In 1961-1966, Robert E. Stewart and Harold A. Kantrud conducted a study to investigate the relationship of wetland plant communities to variations of water permanence and chemistry on three study areas: Crystal Springs, Cottonwood, and Mt. Moriah. Within in this region, a severe drought occurred in 1988- 1992 followed by the longest deluge starting in 1993 with wetlands still impacted today. In 2013 and 2014, I revisited 80 of the original wetlands …


Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta Jan 2016

Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta

Electronic Theses and Dissertations

Ferruginous hawks (Buteo regalis) are a grassland and shrubland obligate nesting raptor and prefer lightly grazed pasture or idle areas for nesting. Their population reportedly declines in number if more than 30% of an area is cultivated and they rarely nest in areas dominated by croplands. Golden eagles (Aquila chrysaetos) are long-lived raptors with high nest-site fidelity and relatively low reproductive success. Population trends of golden eagles in western United States are unclear although long-term monitoring of populations shows declines in occupancy and breeding performance. Northern harriers (Circus cyaneus) prefer relatively open grasslands and …


Performance Measures Of Road Crossing Structures From Relative Movement Rates Of Large Mammals, Adam Andis Jan 2016

Performance Measures Of Road Crossing Structures From Relative Movement Rates Of Large Mammals, Adam Andis

Graduate Student Theses, Dissertations, & Professional Papers

In recent decades, there has been an increase of engineering projects that seek to mitigate the barrier effect roads impose on wildlife by installing wildlife crossing structures that promote permeability of the road corridor. The 41 fish and wildlife crossing structures installed along a 90km stretch of US Highway 93 on the Flathead Indian Reservation in western Montana, represent one of the most extensive of such projects in North America. As mitigation efforts are increasingly considered and implemented in road construction projects, the need to assess these structures’ effectiveness grows. This study is the first to compare observations of animal …


Current Status Of Falcon Populations In Saudi Arabia, Albara M. Binothman Jan 2016

Current Status Of Falcon Populations In Saudi Arabia, Albara M. Binothman

Electronic Theses and Dissertations

Falcons (Falco spp.) are widely used for falconry in the countries of the Middle East. During the 2015 breeding season, we surveyed historic and active nest sites of Barbary (Falco pelegrinoides pelegrinoides) and Lanner (F. biarmicus) Falcons in Saudi Arabia. Field and questionnaire surveys were conducted and personal contact with falconers was made to document the current distribution and price changes for Lanner Falcons, Barbary Falcons, Saker Falcons (F. cherrug), Peregrine Falcons (F. peregrinus), Gyrfalcons (F. rusticolus), and Hybrid Falcons in Saudi Arabia. We categorized our survey into three geographic groups; southwest (A), northwest (B), and central (C) regions of …


Active Aggregation Among Sexes In Bean Flower Thrips (Megalurothrips Sjostedti) On Cowpea (Vigna Unguiculata), Saliou Niassy, Sunday Ekesi, Nguya K. Maniania, Benedict Orindi, Gerald B. Moritz, Willem J. De Kogel, Sevgan Subramanian Jan 2016

Active Aggregation Among Sexes In Bean Flower Thrips (Megalurothrips Sjostedti) On Cowpea (Vigna Unguiculata), Saliou Niassy, Sunday Ekesi, Nguya K. Maniania, Benedict Orindi, Gerald B. Moritz, Willem J. De Kogel, Sevgan Subramanian

All Peer-Reviewed Publications

Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour observed in diverse organisms, including insects such as thrips. The influence of factors such as plant substrate, time of day, and geographic location on aggregation of thrips is uncertain, therefore we monitored the dispersion of male and female bean flower thrips (BFT), Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), on cowpea, Vigna unguiculata (L.) Walp. (Fabaceae), over three cowpea growth stages and across three cowpea-growing areas of Kenya. Our results indicated that for all the crop growth stages, the density of BFTs varied over the time of day, with higher densities …


Host Location And Host-Associated Divergence In Parasitoids Of The Gall Midge, Asteromyia Carbonifera, Jeffrey L. Howell Jan 2016

Host Location And Host-Associated Divergence In Parasitoids Of The Gall Midge, Asteromyia Carbonifera, Jeffrey L. Howell

Browse all Theses and Dissertations

Some of the world's greatest mysteries are the series of ecological and behavioral processes that promote adaptive radiation: when one species rapidly diverges into multiple descendants due to ecological selective pressures. Selective pressures from natural enemies have the potential to drive such radiations, as has been suggested in the diversification of the goldenrod gall-midge, Asteromyia carbonifera (Stireman et al., 2008, 2012). This complex, multitrophic system involves the midge species complex, their goldenrod host plants (Solidago sp.), and a suite of parasitoid enemies in the diverse wasp superfamily, Chalcidoidea. There is evidence that the midge is undergoing host-associated differentiation (HAD), in …


The Biotic Effects Of Tertiary Geoclimatic Change In The Southern Hemisphere, Stuart Val Nielsen Jan 2016

The Biotic Effects Of Tertiary Geoclimatic Change In The Southern Hemisphere, Stuart Val Nielsen

Electronic Theses and Dissertations

I explore how pre-Quaternary geoclimatic phenomena and geographical heterogeneity influenced sub-continental speciation processes and contemporary biogeographic patterns across the Southern Hemisphere, with particular focus on two regions that have experienced elevated levels of ongoing aridification – sub-Saharan (particularly Southern) Africa and Australia. I used standard methods from the molecular phylogeneticists’ toolbox (e.g. tree building using maximum likelihood and Bayesian approaches, haplotype networks, uncorrected p-distances) combined with environmental niche modeling, morphometric principal components and fossil calibrated molecular dating analyses in order to ascertain the role that Miocene geo-climatic events played in promoting lineage accumulation and diversification through time. I found a …