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Full-Text Articles in Life Sciences

Development And Validation Of An Edna Protocol For Monitoring Endemic Asian Spiny Frogs In The Himalayan Region Of Pakistan, Muhammad Saeed, Muhammad Rais, Ayesha Akram, Maggie R. Williams, Kenneth F. Kellner, Syed A. Hashsham, Drew R. Davis Apr 2022

Development And Validation Of An Edna Protocol For Monitoring Endemic Asian Spiny Frogs In The Himalayan Region Of Pakistan, Muhammad Saeed, Muhammad Rais, Ayesha Akram, Maggie R. Williams, Kenneth F. Kellner, Syed A. Hashsham, Drew R. Davis

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Wildlife monitoring programs are instrumental for the assessment of species, habitat status, and for the management of factors affecting them. This is particularly important for species found in freshwater ecosystems, such as amphibians, as they have higher estimated extinction rates than terrestrial species. We developed and validated two species-specific environmental DNA (eDNA) protocols and applied them in the field to detect the Hazara Torrent Frog (Allopaa hazarensis) and Murree Hills Frog (Nanorana vicina). Additionally, we compared eDNA surveys with visual encounter surveys and estimated site occupancy. eDNA surveys resulted in higher occurrence probabilities for both A. …


Desktop Scanning Electron Microscopy In Plant-Insect Interactions Research: A Fast And Effective Way To Capture Electron Micrographs With Minimal Sample Preparation, Sakshi Watts, Ishveen Kaur, Sukhman Singh, Bianca Jimenez, Jesus Chavana, Rupesh R. Kariyat Oct 2021

Desktop Scanning Electron Microscopy In Plant-Insect Interactions Research: A Fast And Effective Way To Capture Electron Micrographs With Minimal Sample Preparation, Sakshi Watts, Ishveen Kaur, Sukhman Singh, Bianca Jimenez, Jesus Chavana, Rupesh R. Kariyat

Biology Faculty Publications and Presentations

The ability to visualize cell and tissue morphology at a high magnification using scanning electron microscopy (SEM) has revolutionized plant sciences research. In plant-insect interactions studies, SEM based imaging has been of immense assistance to understand plant surface morphology including trichomes (plant hairs; physical defense structures against herbivores (Kaur and Kariyat, 2020a, 2020b; Watts and Kariyat, 2021), spines, waxes, and insect morphological characteristics such as mouth parts, antennae, and legs, that they interact with. While SEM provides finer details of samples, and the imaging process is simpler now with advanced image acquisition and processing, sample preparation methodology has lagged. The …


Local Adaptation To Continuous Mowing Makes The Noxious Weed Solanum Elaeagnifolium A Superweed Candidate By Improving Fitness And Defense Traits, Jesus Chavana, Sukhman Singh, Alejandro Vazquez, Bradley O. Christoffersen, Alexis Racelis, Rupesh R. Kariyat Mar 2021

Local Adaptation To Continuous Mowing Makes The Noxious Weed Solanum Elaeagnifolium A Superweed Candidate By Improving Fitness And Defense Traits, Jesus Chavana, Sukhman Singh, Alejandro Vazquez, Bradley O. Christoffersen, Alexis Racelis, Rupesh R. Kariyat

Biology Faculty Publications and Presentations

The role of disturbance in accelerating weed growth is well understood. While most studies have focused on soil mediated disturbance, mowing can also impact weed traits. Using silverleaf nightshade (Solanum elaeagnifolium), a noxious and invasive weed, through a series of field, laboratory, and greenhouse experiments, we asked whether continuous mowing influences growth and plant defense traits, expressed via different avenues, and whether they cascade into offspring. We found that mowed plants produced significantly less number of fruits, and less number of total seeds per plant, but had higher seed mass, and germinated more and faster. When three herbivores …


First Description Of Deep Benthic Habitats And Communities Of Oceanic Islands And Seamounts Of The Nazca Desventuradas Marine Park, Chile, Jan M. Tapia-Guerra, Ariadna Mecho, Erin E. Easton, María De Los Ángeles Gallardo, Matthias Gorny, Javier Sellanes Mar 2021

First Description Of Deep Benthic Habitats And Communities Of Oceanic Islands And Seamounts Of The Nazca Desventuradas Marine Park, Chile, Jan M. Tapia-Guerra, Ariadna Mecho, Erin E. Easton, María De Los Ángeles Gallardo, Matthias Gorny, Javier Sellanes

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Seamounts and oceanic islands of the Chilean Exclusive Economic Zone at the intersection of the Nazca and Salas y Gómez ridges lie within one of the least explored areas in the world. The sparse information available, mainly for seamounts outside Chilean jurisdiction and shallow-water fauna of the Desventuradas Islands, suggests that the area is a hotspot of endemism. This apparent uniqueness of the fauna motivated the creation of the large Nazca-Desventuradas Marine Park (NDMP, ~ 300,000 km2) around the small islands San Felix and San Ambrosio in 2015. We report for the first time a detailed description of benthic microhabitats …


Molecular Characterization Of A Marine Turtle Tumor Epizootic, Profiling External, Internal And Postsurgical Regrowth Tumors, Kelsey Yetsko, Jessica A. Farrell, Nicholas B. Blackburn, Liam Whitmore, Maximilian R. Stammnitz, Jenny Whilde, Catherine B. Eastman, Devon Rollinson Ramia, Ana C. Leandro Feb 2021

Molecular Characterization Of A Marine Turtle Tumor Epizootic, Profiling External, Internal And Postsurgical Regrowth Tumors, Kelsey Yetsko, Jessica A. Farrell, Nicholas B. Blackburn, Liam Whitmore, Maximilian R. Stammnitz, Jenny Whilde, Catherine B. Eastman, Devon Rollinson Ramia, Ana C. Leandro

School of Medicine Publications and Presentations

Sea turtle populations are under threat from an epizootic tumor disease (animal epidemic) known as fibropapillomatosis. Fibropapillomatosis continues to spread geographically, with prevalence of the disease also growing at many longer-affected sites globally. However, we do not yet understand the precise environmental, mutational and viral events driving fibropapillomatosis tumor formation and progression.

Here we perform transcriptomic and immunohistochemical profiling of five fibropapillomatosis tumor types: external new, established and postsurgical regrowth tumors, and internal lung and kidney tumors. We reveal that internal tumors are molecularly distinct from the more common external tumors. However, they have a small number of conserved potentially …


Effects Of Integrated Application Of Plant-Based Compost And Urea On Soil Food Web, Soil Properties, And Yield And Quality Of A Processing Carrot Cultivar, A. Habteweld, D. Brainard, A. Kravchencko, Parwinder Grewal, H. Melakeberhan Jan 2020

Effects Of Integrated Application Of Plant-Based Compost And Urea On Soil Food Web, Soil Properties, And Yield And Quality Of A Processing Carrot Cultivar, A. Habteweld, D. Brainard, A. Kravchencko, Parwinder Grewal, H. Melakeberhan

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Soil nutrient management system characterized by reduced input of inorganic fertilizers integrated with organic amendments is one of the alternatives for reducing deleterious environmental impact of synthetic fertilizers, suppressing soil-borne pests and diseases, and improving soil health and crop yield. A hypothesis of the present study was that lower rates of urea mixed with higher rates of plant compost (PC) would improve nematode community structure, soil food web condition, soil biological, and physiochemical properties, and yield and quality of a processing carrot (Daucus carota) cultivar. Urea and PC were each applied at 135kg nitrogen (N)/ha alone or at 3:1, 1:1, …


Non-Invasive Methods For Measuring And Monitoring Stress Physiology In Imperiled Amphibians, Edward J. Narayan, Zachery R. Forsburg, Drew R. Davis, Caitlin R. Gabor Nov 2019

Non-Invasive Methods For Measuring And Monitoring Stress Physiology In Imperiled Amphibians, Edward J. Narayan, Zachery R. Forsburg, Drew R. Davis, Caitlin R. Gabor

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Global climate change is negatively impacting global biodiversity and ectothermic vertebrates, with amphibians being the most imperiled vertebrate taxa. Increased mean global atmospheric temperatures, high rates of habitat degradation, and exposure to infectious diseases, such as chytridiomycosis, have contributed to population declines and extinctions of rare and endangered amphibian species. Field-based monitoring of physiological endocrine traits can help determine the sub-lethal effects of environmental stressors and provide early alerts when populations are chronically stressed. Recent advances in amphibian stress endocrinology include the development and use of non-invasive methods to quantify the glucocorticoid, or stress biomarker, corticosterone. Non-invasive methods, such as …


Increasing Impacts Of Extreme Droughts On Vegetation Productivity Under Climate Change, Chonggang Xu, Nate G. Mcdowell, Rosie A. Fisher, Liang Wei, Sanna Sevanto, Bradley O. Christoffersen, Engsheng Weng, Richard S. Middleton Nov 2019

Increasing Impacts Of Extreme Droughts On Vegetation Productivity Under Climate Change, Chonggang Xu, Nate G. Mcdowell, Rosie A. Fisher, Liang Wei, Sanna Sevanto, Bradley O. Christoffersen, Engsheng Weng, Richard S. Middleton

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Terrestrial gross primary production (GPP) is the basis of vegetation growth and food production globally1 and plays a critical role in regulating atmospheric CO2 through its impact on ecosystem carbon balance. Even though higher CO2 concentrations in future decades can increase GPP2, low soil water availability, heat stress and disturbances associated with droughts could reduce the benefits of such CO2 fertilization. Here we analysed outputs of 13 Earth system models to show an increasingly stronger impact on GPP by extreme droughts than by mild and moderate droughts over the twenty-first century. Due to a dramatic increase in …


Agricultural Intensification And Urbanization Negatively Impact Soil Nematode Richness And Abundance: A Meta-Analysis, Satyendra K. Pothula, Parwinder Grewal, Robert M. Auge, Arnold M. Saxton, Ernest C. Bernard Apr 2019

Agricultural Intensification And Urbanization Negatively Impact Soil Nematode Richness And Abundance: A Meta-Analysis, Satyendra K. Pothula, Parwinder Grewal, Robert M. Auge, Arnold M. Saxton, Ernest C. Bernard

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Human activity has extensively transformed the land surface by agricultural intensification and urbanization. In soil, nematodes are the most abundant invertebrates. The effect of human interventions was assessed on overall richness, overall abundance, richness and abundance of nematodes of each trophic group and colonizer-persister (c-p) guild by comparing urban, agriculture and disturbed grassland (DGL) with natural grassland (NGL) and forest ecosystems. Meta-analyses were conducted to generate quantitative summaries from 111 published articles that met the inclusion criteria, 91 expressed data in grams and 20 expressed data in cm3. Results from data expressed per 100 g of soil indicated that overall …


Population Dynamics Of Off-Host Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae) Larvae In Response To Habitat And Seasonality In South Texas, Brenda Leal, Donald B. Thomas, Robert K. Dearth Mar 2018

Population Dynamics Of Off-Host Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae) Larvae In Response To Habitat And Seasonality In South Texas, Brenda Leal, Donald B. Thomas, Robert K. Dearth

Biology Faculty Publications and Presentations

The cattle tick, Rhipicephalus microplus (Canestrini), is an economically destructive arthropod because of its ability to vector bovine babesiosis. It is known that cattle ticks can spend 80–90% of their lifecycle as questing larvae, yet the effect of climatic factors on their off-host behavior and survival is unclear. The goal of this study was to measure the effects of specific ecological factors on off-host questing larvae in nature. The study was conducted in a south Texas pasture over a two-year period, during which time larval populations were surveyed. Simultaneously, weather variables—precipitation, relative humidity, and ambient temperatures—were recorded. Larval survival rates …


Preliminary Multivariate Comparison Of Coral Assemblages On Carbonate Banks In The Western Gulf Of Mexico, Rebekah E. Rodriguez, Erin E. Easton, Thomas C. Shirley, John W. Tunnell, David Hicks Jan 2018

Preliminary Multivariate Comparison Of Coral Assemblages On Carbonate Banks In The Western Gulf Of Mexico, Rebekah E. Rodriguez, Erin E. Easton, Thomas C. Shirley, John W. Tunnell, David Hicks

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Hermatypic corals flourished on reefs in the Gulf of Mexico (GOM) in the late Pleistocene and early Holocene. Today, many of these relict reefs are mesophotic banks that have unique coral assemblages and provide critical habitat; however, the South Texas Banks (STB) lack quantitative surveys. Therefore, we used a remotely operated vehicle to conduct quantitative surveys of 5 banks: Baker, Aransas, Dream, Blackfish Ridge, and Harte. Coral communities, based on estimated coral densities (colonies/m2), significantly differed among banks for terraces, slopes, and overall (combined terrace and slope) communities for most banks examined. Within banks, terrace and slope communities significantly differed …


Efectos Del Cambio Climático En La Interacción Planta-Hormiga: Una Mini Revisión Sobre La Tolerancia Térmica, Florencio Luna Castellanos, Mariana Cuautle, Teresa Patricia Feria-Arroyo, Citlalli Castillo Guevara Jan 2017

Efectos Del Cambio Climático En La Interacción Planta-Hormiga: Una Mini Revisión Sobre La Tolerancia Térmica, Florencio Luna Castellanos, Mariana Cuautle, Teresa Patricia Feria-Arroyo, Citlalli Castillo Guevara

Biology Faculty Publications and Presentations

Sin duda alguna el clima está cambiando debido al aumento de la concentración de gases de efecto invernadero en la atmósfera provocado por la acción humana. Dichos cambios van a tener un efecto importante en algunas actividades humanas tales como la agricultura y también pueden afectar enormemente la distribución geográfica de los organismos vivos y por tanto sus interacciones. Las hormigas y las plantas tienen una larga historia evolutiva de interacción. La actividad de las hormigas y su relación con las plantas en los últimos años ha tenido un número creciente de estudios que están poniendo de relieve su papel …


Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal Dec 2016

Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal

Theses and Dissertations

The objective of this investigation was to examine the foraging patterns and population density of the Buff-bellied Hummingbird (Amazilia yucatanensis ) in Hidalgo County, TX. Previous studies showed that hummingbirds use flowers displaying traditional bird pollination (ornithophilous) characteristics: reddish coloration, tubular corolla, and extended anthers. Observation sessions noted type and frequency of flowering species utilized for nectar, characteristics, and number of individuals seen in each area. Amazilia yucatanensis showed higher use of ornithophilous flowers. Significant results found: f-ratio 5.45 > p-value (0.05) 3.24. Two highly utilized species showed the expected 20–40% sucrose content expected in ornithophilous flowers. Population density per …


Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez Dec 2013

Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez

Theses and Dissertations - UTB/UTPA

This study investigated the relationship between Anopheles abundance, collection sites and environmental variables in the Lower Rio Grande Valley, South Texas. In addition, species composition in the Lower Rio Grande Valley was determined in 2011. A total of 6772 female mosquitoes were identified to six genera and 27 species. The most prevalent genera collected were Culex (53.9%), Ochlerotatus (25.6%) and Aedes (13.6%). Anopheles mosquitoes were collected using resting boxes during summer 2012 at multiple locations along the Lower Rio Grande Valley. ArcGIS was used to identify land cover characteristics and nearest water sources at mosquito collection sites. Estero Llano Grande …


Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora Dec 2009

Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora

Theses and Dissertations - UTB/UTPA

Nerodia rhombifer is a polytypic, semi-aquatic snake with a broad geographical distribution ranging from the American Midwest southward to Chiapas, Mexico. Although relatively abundant throughout much of its range, few ecological studies of the species have been conducted. This study provides basic population ecology information in a subtropical habitat. Population data were obtained in a mark-recapture study at Santa Ana National Wildlife Refuge, Hidalgo County, Texas, from August 1995 to December 1998. Specimens taken elsewhere in Hidalgo County provided information on the reproductive biology. This study provides the first absolute density estimates from anywhere within the species’ range. Quantitative information …


The Influence Of Environmental Factors On The Activity And Movement Of Bufo Nebulifer (Coastal Plain Toad) In A Disturbed Area, Crystal Salinas Jul 2009

The Influence Of Environmental Factors On The Activity And Movement Of Bufo Nebulifer (Coastal Plain Toad) In A Disturbed Area, Crystal Salinas

Theses and Dissertations - UTB/UTPA

Toads in the family Bufonidae are poorly studied in southern Texas. Bufo nebulifir, a native bufonid, has been studied in its northern and southern range limits (east Texas and northern Mexico). South Texas' sub-tropical climate could impact the length of the activity period for B. nebulifer in yet unrecorded ways. This study resolves whether environmental factors correlate to Bufo nebulifer's activity, presence, and movement, using a mark-recapture method. The study was conducted for one year during February 2008 to March 2009. Environmental factors, especially rainfall and temperature were significantly correlated (PB. nebulifer . The active period of B. …


Comparative Pollen Foraging Of Africanized And European Honeybees In A Non-Agricultural Environment, Ruben Ruiz May 2006

Comparative Pollen Foraging Of Africanized And European Honeybees In A Non-Agricultural Environment, Ruben Ruiz

Theses and Dissertations - UTB/UTPA

With the advent of the Africanized honeybee, ways to differentiate it from the European honeybee have been greatly sought in attempts to better understand the role of Africanized bees in pollination. Pollen collecting strategies for both honeybee subspecies have been explored in attempts to exploit their pollinating capabilities. This project examined pollen collected by honeybees from feral and managed European and Africanized colonies in a relatively isolated site. Paired European and Africanized honeybee colonies were used to obtain pollen foragers. Through acetolysis (series acidified Acetic Anhydride washings); the collected pollen from the individual foragers was treated and observed with light …


Regional Ecological Resource Assessment Of The Rio Grande Riparian Corridor: A Multidisciplinary Approach To Understanding Anthropogenic Effects On Riparian Communities In Semi-Arid Environments, Jay Raney, Amy Neuenschwander, Frank W. Judd, Gene Paull, Melba Crawford, Robert I. Lonard, Tatiana Encheva, Thomas Tremblay, William White Jan 2004

Regional Ecological Resource Assessment Of The Rio Grande Riparian Corridor: A Multidisciplinary Approach To Understanding Anthropogenic Effects On Riparian Communities In Semi-Arid Environments, Jay Raney, Amy Neuenschwander, Frank W. Judd, Gene Paull, Melba Crawford, Robert I. Lonard, Tatiana Encheva, Thomas Tremblay, William White

Biology Faculty Publications and Presentations

Riparian ecosystems of the Southwestern United States are among the most productive ecosystems of North America. The rapid decline of these ecosystems throughout the United States, including the Lower Rio Grande Valley, has made riparian conservation a focal issue. This was a multidisciplinary study of riparian communities along the Lower Rio Grande Valley of Texas and Mexico. The objectives of this research project were to: (1) acquire and analyze high-resolution, remotely sensed data from multiple sensors; (2) integrate existing and new field data and remotely sensed data into a geographic information system (GIS); (3) ascertain whether the native vegetation communities …


Effect Of Artificial Flooding On The Vegetation And Avifauna Of Riparian Woodlands At Santa Ana National Wildlife Refuge, Hidalgo County, Texas, Charles David Castillo Dec 1997

Effect Of Artificial Flooding On The Vegetation And Avifauna Of Riparian Woodlands At Santa Ana National Wildlife Refuge, Hidalgo County, Texas, Charles David Castillo

Theses and Dissertations - UTB/UTPA

Riparian habitats along the Rio Grande at Santa Ana National Wildlife Refuge have dramatically decreased since the construction of Falcon Dam in 1953. Riparian habitats are dependent on annual or periodic flooding to maintain their biological integrity. Lack of seasonal flooding has contributed to changes in vegetative composition from riparian forests to thornscrub. Effects of artificial flooding on vegetation and avifauna of riparian woodlands were evaluated from 1995-1997 at the Santa Ana National Wildlife Refuge. Floodwaters caused the destruction of all existing herbaceous species along study transects and the regeneration of new and native seedlings. Avian abundance and diversity dramatically …


Habitat Selection, Population Density, And Home Range Of The Elf Owl, Micrathene Whitneyl, At Santa Ana National Wildlife Refuge, Texas, Christopher Michael Gamel May 1997

Habitat Selection, Population Density, And Home Range Of The Elf Owl, Micrathene Whitneyl, At Santa Ana National Wildlife Refuge, Texas, Christopher Michael Gamel

Theses and Dissertations - UTB/UTPA

The Elf Owl, Micrathene whitneyi, is a regular summer resident of the southwestern United States. My objectives were to collect information concerning habitat selection, home range size, and population density of M. w. idonea, the subspecies occurring in the Lower Rio Grande Valley of Texas. Nocturnal surveys indicated greater use of chaparral habitat (92%) compared to riparian woodlands (8%). Utilized habitat was characterized by highest foliage density at 2.5-3.0 m, with a partial canopy at 3.8 $\pm$ 0.36 m and a semi-open understory. Home range size ranged from 0.24 to 2.6 ha, with a mean of 1.05 $\pm$ 0.33 ha. …


Using The Spot-Mapping Censusing Technique To Assess Changes In Breeding Bird Communities At Santa Ana National Wildlife Refuge, Alamo, Texas, 1940-1996, Alberto Cantu Nov 1996

Using The Spot-Mapping Censusing Technique To Assess Changes In Breeding Bird Communities At Santa Ana National Wildlife Refuge, Alamo, Texas, 1940-1996, Alberto Cantu

Theses and Dissertations - UTB/UTPA

Results of breeding-bird censuses done by Davis in 1940 and by Gehlbach between 1973-1978 at Santa Ana National Wildlife, Alamo Texas, were compared to a 1995-1996 bird survey done in Gehlbach's study area. According to the Wilcoxon rank-sum test, bird densities in 1940 and 1995-1996 were similar, while 1973-1978 densities were lower. The 1995-1996 bird community was 76% similar to both the earlier studies. However, the communities studied in 1940 and 1973-1978 had only a 60% similarity. Negligible differences in bird densities and species composition were found between the 1995 and 1996 communities. Differences are attributed to changes in vegetation …


A Comparison Of Secondary Successional Woody Vegetation In Two Revegetated Fields In South Texas And An Assessment Of Habitat Use By The Olive Sparrow, Arremonops Rufivirgatus, Patrick Grant Wright Jun 1996

A Comparison Of Secondary Successional Woody Vegetation In Two Revegetated Fields In South Texas And An Assessment Of Habitat Use By The Olive Sparrow, Arremonops Rufivirgatus, Patrick Grant Wright

Theses and Dissertations - UTB/UTPA

Aspects of plant species composition and structure of two revegetated fields in western Cameron County, Texas, were studied between 1992 and 1995. Avian habitat suitability was assessed using the Olive Sparrow, Arremonops rufivirgatus, as an indicator species. Total vegetation volume at the Longoria Wildlife Management Area (WMA), an area revegetated in 1961, was 0.745 $\rm m\sp3V/m\sp2$ and that of the Anacua WMA, revegetated in 1983-4, was 0.546 $\rm m\sp3V/m\sp2$ in 1992. Secondary woody species at the Longoria and Anacua WMA's had a Shannon's index of diversity of 0.619 and 0.264, respectively. Secondary woody vegetation at the Longoria WMA had a …