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Full-Text Articles in Biology

Employing Natural History Collections In The Aid Of Conservation: Streamlining An Approach To Model Species Distributions En Masse For The Preservation Of Biodiversity, Alice Fornari Dec 2018

Employing Natural History Collections In The Aid Of Conservation: Streamlining An Approach To Model Species Distributions En Masse For The Preservation Of Biodiversity, Alice Fornari

Master's Projects and Capstones

Using species distribution models (SDMs) in Natural History Collections (NHCs) can influence how humans implement conservation changes in flora and fauna communities and ecosystems. Through the use of legacy data (old NHCs and their associated locality/collection information), data correction (background data or pseudo absences added to presence-only data), and the SDM software, Maxent (and its associated geographic information systems or GIS projected models), it has been shown that it is feasible to create a low budget protocol/setup to project the past, present and future of species population changes. This has been done in the past few decades as more collections …


Bubble Stream Production By Belugas (Delphinapterus Leucas), Megan Slack Aug 2018

Bubble Stream Production By Belugas (Delphinapterus Leucas), Megan Slack

Theses

Bubble stream production in belugas has been poorly characterized and its function is not well understood. I examined behavioral states when producing bubble streams (“bubbling”), and when bubbling calls, to determine whether bubbling was significantly associated with a particular call category or behavioral state. Using 19 hours of video and audio recordings collected over a two-day period, I quantified bubble streams of a 4-month old calf and an unrelated adult female housed together. Based on the overall activity budgets and pool of vocalizations for both animals, I calculated the expected counts of bubble streams with and without vocalizations, assuming that …


Unique Osmoregulatory Morphology In Primitive Sharks: An Intermediate State Between Holocephalan And Derived Shark Secretory Morphology, Matthew Eric Larsen Jul 2018

Unique Osmoregulatory Morphology In Primitive Sharks: An Intermediate State Between Holocephalan And Derived Shark Secretory Morphology, Matthew Eric Larsen

Electronic Theses and Dissertations

Discovery of an unusual rectal gland in the Atlantic sixgill shark, Hexanchus vitulus, led to examination of rectal glands in 29 species of epipelagic and deep-sea sharks. Eight of 14 deep-sea species of sharks had digitiform glands that were previously assumed to be characteristic of elasmobranchs (N=281; mean width-length ratio ± SD = 0.18 ± 0.07). Hematoxylin-and-eosin stained sections from deep-sea sharks were similar to those from shallow water sharks. Glands from the family Somniosidae were kidney bean-shaped (N = 3; mean width-length ratio ± SD = 0.46 ± 0.05); whereas those from the families Echinorhinidae and Hexanchidae appeared lobulate …


Digging Biomechanics In Geomyoid Rodents, Alexis Moore Crisp May 2018

Digging Biomechanics In Geomyoid Rodents, Alexis Moore Crisp

UNLV Theses, Dissertations, Professional Papers, and Capstones

Subterranean digging behaviors provide opportunities for protection, access to prey, and predator avoidance for a diverse array of vertebrates, yet studies of the biomechanics of burrowing have been limited by the technical challenges of measuring kinetics and kinematics of animals moving within a substrate. Prior studies of burrowing have recorded a single axis of x-ray video and/or force. However, empirical observations show that burrowing is not restricted to a single axis or plane. I describe a new system called a ‘tunnel-tube’ for measuring 3D reaction force during burrowing. This tunnel-tube has two separate tubes, one ‘entry tube’ that has no …


Whence And Whither: Acoustic Variability And Biogeography Of Tarsiers In North Sulawesi, Olivia Clare Kulander Mar 2018

Whence And Whither: Acoustic Variability And Biogeography Of Tarsiers In North Sulawesi, Olivia Clare Kulander

Dissertations and Theses

The morning duet calls of eastern tarsiers (Tarsius spp.) in North Sulawesi were recorded and analyzed to examine the effects of geography and geologic history on their call structure. Tarsius species exhibit interspecifically variable duet calls shown to correlate with species differentiation and distribution. They are distributed across Sulawesi, a biogeographically complex island in the Indonesian archipelago, where tectonic activity and multiple glaciations during the Pleistocene generated and modified barriers to their dispersal and gene flow.

Recordings were made at ten locations from November of 2012 through June of 2014. Two locations were categorized as mainland, while eight island …


Diet Composition Explains Reductions In Stream Salamander Occupancy And Abundance Along A Conductivity Gradient, Jacob Matthew Hutton Jan 2018

Diet Composition Explains Reductions In Stream Salamander Occupancy And Abundance Along A Conductivity Gradient, Jacob Matthew Hutton

Theses and Dissertations--Forestry and Natural Resources

Changes in land use such as mountaintop removal mining with valley fills (MTR/VF) affect chemical, physical, and hydrological properties of headwater streams. Although numerous stream taxa have experienced significant declines from MTR/VF, stream salamanders appear to be particularly sensitive. Yet, the specific mechanism(s) responsible for the population declines has eluded researchers. We sampled salamander assemblages across a continuous specific conductivity (SC) gradient in southeastern Kentucky and estimated occupancy rates and abundance estimates along this gradient. We also examined the diet of larval and adult salamanders to determine if autochthony (A/T prey), total prey volume, and body condition is influenced by …


Birds And Vegetation Structure Of Isolated Juniper And Oak Communities In The Trans-Pecos Chihuahuan Desert., Kayla Garza Jan 2018

Birds And Vegetation Structure Of Isolated Juniper And Oak Communities In The Trans-Pecos Chihuahuan Desert., Kayla Garza

Open Access Theses & Dissertations

Birds of the Trans-Pecos region are historically understudied, with most literature covering birds of desert grasslands and scrub in New Mexico and Northern Mexico. A multitude of vegetation communities within the Chihuahuan Desert have also been neglected due to this gap in the research, for reasons including lack of access to public or preserve land in West Texas, and rough terrain. Indio Mountains Research Station (IMRS), is located 42-km southwest of Van Horn, Texas and encompasses many different vegetation communities, including juniper-oak habitats of arroyo and canyon systems. The purpose of this study was to document the bird species utilizing …


A Chronology Of Diet And Habitat Use In The Florida Manatee (Trichechus Manatus Latirostris): Insights From Stable Isotope Analysis, Malia Smith Jan 2018

A Chronology Of Diet And Habitat Use In The Florida Manatee (Trichechus Manatus Latirostris): Insights From Stable Isotope Analysis, Malia Smith

Williams Honors College, Honors Research Projects

The Florida Manatee (Trichechus manatus latirostris) is a threatened species that primarily feeds on marine and estuarine seagrasses. Over the past several years, the seagrass coverage in the Indian River Lagoon has varied due to human influence and algal blooms. This led to an unusual number of manatees dying and potentially, to remaining manatees shifting their diets. It can be difficult to decipher why or how diets shift, however, creating a timeline using stable isotopes can help address this challenge. Red blood cells from live Florida Manatees were analyzed for stable carbon, nitrogen, and sulfur isotope ratios. All …


Single And Pair Housed Chacma Baboons’ (Papio Ursinus) Response To Caregivers’ Use Of Species-Specific Behavior, Josefine Holm Jan 2018

Single And Pair Housed Chacma Baboons’ (Papio Ursinus) Response To Caregivers’ Use Of Species-Specific Behavior, Josefine Holm

All Master's Theses

Most captive primates suffer from stereotypical or abnormal behavior which can be reduced by implementing enrichment protocols. There is, however, often spatial or economic limitations to facilities’ enrichment programs, and implementing the most beneficial and cost-effective enrichment is therefore crucial to ensure the best welfare for captive primates. Social enrichment has been designated as the most effective type of enrichment, but often captive primates cannot be housed in social groups. Through this study, I wanted to determine if species-specific behavioral interactions between human caregivers and captive chacma baboons (Papio ursinus)would alter the baboons’ behaviors, and if these interactions could …


Evidence For Extra-Gastric Expression Of The Proton Pump H+/K+ -Atpase In The Gills And Kidney Of The Teleost Oreochromis Niloticus, Ebtesam Barnawi Jan 2018

Evidence For Extra-Gastric Expression Of The Proton Pump H+/K+ -Atpase In The Gills And Kidney Of The Teleost Oreochromis Niloticus, Ebtesam Barnawi

Theses and Dissertations (Comprehensive)

It is well known that stomach acid secretion by oxynticopeptic cells of the gastric mucosa is accomplished by the H+/ K+-ATPase (HKA), which is comprised of the HKα1 (gene: atp4a) and HKβ (gene: atp4b) subunits. However, the role of the HKA in extra-gastric organs such as the gill and kidney is less clear especially in fishes. This pump may contribute to active ion and/or acid-base regulation either through direct ion transport or through secondary transport proteins against unfavorable concentration gradients via the energy derived from ATP hydrolysis. In the present work I have demonstrated …


Gill Structure & Function In Parasitic And Non-Parasitic Lampreys: The Effects Of Metamorphosis And Freshwater-Seawater Transfer, Julia Sunga Jan 2018

Gill Structure & Function In Parasitic And Non-Parasitic Lampreys: The Effects Of Metamorphosis And Freshwater-Seawater Transfer, Julia Sunga

Theses and Dissertations (Comprehensive)

Lamprey (Petromyzontiformes) are a phylogenetically ancient group of jawless fishes that begin their lives as filter-feeding larvae (ammocoetes) before undergoing a complex metamorphosis into juvenile lamprey that involves major changes to their internal and external body plan. Some parasitic species, such as the sea lamprey (Petromyzon marinus), migrate to sea following metamorphosis, where they use their oral discs and rasping tongue to attach to and ingest vast quantities of blood from fishes. Thus, sea lamprey have to counter the simultaneous challenges of hyposmoregulation in sea water and the generation of large quantities of ammonia due to the …