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Item A Cholinergic Sensory-Motor Circuit Controls the Male Copulation Behavior in C. elegans(2012-07-16) Liu, YishiThe nervous system coordinates a sequence of muscle movements to give rise to animal behaviors. In complex invertebrates or lab-studied vertebrates, due to the large number of cells in their nervous systems and the complexities of their behaviors, it is difficult to address how circuits process information to direct each motor output of the behavior. In this dissertation, I used the Caenorhabditis elegans male copulation behavior as a model to address how a compact circuit coordinates different behavioral programs. Insertion of a male copulatory organ into a suitable mate is a conserved and necessary behavioral step for most terrestrial mating. However, the detailed molecular and cellular mechanisms for this distinct social interaction have not been elucidated in any animal. During mating, the C. elegans male cloaca is positioned over the hermaphrodite?s vulva as he attempts to insert his copulatory spicules repetitively. Rhythmic spicule thrusts cease when insertion is sensed. Circuit components consisting of sensory/motor neurons and sex muscles for these steps have been previously identified, but it was unclear how their outputs are integrated to generate a coordinated behavior pattern. Here, I show that contraction of the male oblique muscles is required to sustain genital contact between the sexes. These muscles are innervated by the postcloacal sensilla (p.c.s.) sensory/motor neurons, which secret ACh to activate the levamisole-sensitive AChR and the ACR-16-containing ionotropic AChR on the oblique muscles. For spicules to rhythmically thrust during genital contact, activity of the oblique muscles and the gubernacular muscles is transmitted to the spicule protractor muscles instantaneously via gap junctions between these muscles and causes shallow protractor contractions. The rhythmic protractor contractions eventually switch to sustained contraction, as the SPC sensory-motor neurons integrate information of spicule position at the vulva with inputs from the hook and cloacal sensilla. The ERG-like K+ channel, UNC-103, which decreases the spicule circuit excitability, is likely to set a threshold requirement for integration of these inputs, so that sustained spicule muscle contraction is not stimulated by fewer inputs. In addition, I demonstrate that a cholinergic signaling pathway mediated by a muscarinic acetylcholine receptor, GAR-3, is used to enhance the ionotropic AChRs-mediated fast synaptic transmission in the copulation circuit. GAR-3 is expressed in multiple cells of the copulation circuit, but mainly in the cholinergic p.c.s. neurons and SPC neurons. Activation of GAR-3 is coupled to G?q to trigger downstream signal transduction events that modulate neurotransmitter release from these neurons. Males with a loss-of-function allele of the gar-3 gene are defective in inserting their spicules into the hermaphrodite?s vulva efficiently. Since the p.c.s. neurons regulate the male?s contact with the hermaphrodite?s vulva, and the SPC neurons are required for spicule insertion during mating, GAR-3 probably facilitates male mating behavior via enhancing synaptic transmission from these neurons to their postsynaptic partners.Item Artificial Stimulation of Cephalic Cholinergic Sensory Neurons Induces Mating-Like Motor Responses in Male Caenorhabditis elegans(2012-12-06) Midkiff, JamesAll complex organisms possess a nervous system which they use to monitor environmental and internal stimuli. In higher vertebrates, the nervous system is comprised of billions of cells which form highly plastic neural networks from their synapses. These large neural circuits modulate complex behaviors. The nematode roundworm Caenorhabditis elegans uses a small but highly-interconnected nervous system to carry out complex behaviors. The nervous system of C. elegans is a tractable model to determine the effects of changes on a nervous system at the systemic, cellular, genetic, and molecular levels. The C. elegans male?s nervous system detects environmental conditions, mating cues, attractants, repellents, and the location and composition of possible food sources and integrates these inputs to compute the decision of whether or not to mate. Mating behavior in the C. elegans male is regulated at a number of steps by cholinergic signaling from various sensory and sensory-motor neurons, but a comprehensive model of how cholinergic signaling controls this circuit has not yet been elucidated. Previous studies have thoroughly dissected the cellular structure, neural connectivity, and signaling pathways of the male?s peripheral circuits located in the genital regions of the animal?s tail. However, no studies have been conducted to determine what role the cephalic cholinergic neurons have in regulating mating behavior. I hypothesized that cephalic cholinergic neurons exert regulatory control over the male-specific mating circuit. I inserted the transmembrane light-activated ion pore Channelrhodopsin-2 fused to YFP and expressed from the Punc-17small promoter into these neurons and selectively stimulated them using high-intensity blue light. Stimulation induced mating-like behaviors in the male tail consistent with behaviors seen during copulation with a hermaphrodite. Using behavioral assays, I demonstrated that these behaviors were male-specific and only occurred after direct stimulation in the absence of a hermaphrodite. Incidence of mating-like behaviors increased significantly as the worm aged, and the mating circuit retained a memory of the stimulus, indicated by the latency between stimulation and onset of mating-like behaviors. Brief food deprivation, which normally downregulates excitability of the mating circuit via UNC-103 ERG-like K+ channels, caused an unexpected increase in the number of blue light-stimulated behaviors displayed. Pharmacological assays using acetylcholine (ACh) agonists showed that stimulation of the cephalic cholinergic neurons increased propensity for spicule protraction in the presence of an ACh agonist, and partially restored the decline in spicule protraction associated with temporary food deprivation. I sought to identify the cephalic cholinergic neuron or neurons responsible for regulating mating-like behavior in the tail circuits. I looked for a reduction in mating-like behaviors after stimulation after removal of a cephalic cholinergic neuron pair via laser micro-ablation. Two cholinergic and chemosensory neuron pairs in the inner labial sensilla (IL2L/R and IL2VL/R) appear to generate and/or relay the signal that induces mating-like behaviors in the tail. I hypothesize that these neurons sense environmental cues before the male contacts a mate, and modulate lasting motivational changes within the male mating circuit.Item Behavior, association patterns and habitat use of a small community of bottlenose dolphins in San Luis Pass, Texas(Texas A&M University, 2005-11-01) Henderson, Erin ElizabethPhotoidentification surveys of bottlenose dolphins (Tursiops truncatus) were conducted from December of 2002 through December of 2003 in Chocolate Bay, Texas, and the adjacent Gulf of Mexico area. The research represented the continuation of an ongoing study of the dolphins of this area. Behavioral sampling was carried out on a small resident community of dolphins that seasonally reside in Chocolate Bay, as well as on dolphins found along the gulf coastline. Resident dolphins had a daily behavioral pattern, with peaks of foraging activity in the morning, traveling at midday, and socializing in late afternoon. Gulf dolphins had small mean group sizes of 3.4 and were primarily observed foraging and traveling, with little socializing. When resident and gulf dolphins interacted, the mean group size increased to 12 and the proportion of social behavior increased. Association indices demonstrated no long-lasting associations among adult male dolphins, while strong associations existed between several females. Females revealed two patterns of association; they were either members of a female band with other mother-calf pairs, or were solitary with no strong affiliations with any dolphins other than their calf. Males seemed to disperse upon maturation, which maintained the community size of approximately 35 animals. Behavioral evidence indicates the resident community is matrilinealy related and composed largely of adult females and their offspring. A few adult males remain resident, while most young males disperse from the community and may rove among the gulf population. Although mating probably occurs between resident and gulf dolphins, sources of both maternity and paternity for residents need to be determined, and further behavioral work needs to be carried out to support this hypothesis.Item Cellular mechanisms of decision making in Aplysia californicaDickinson, Kathy JanItem Circuits attenuating seizures under well-fed and food-deprived conditions in C. elegans male sex muscles(2010-07-14) Leboeuf, Brigitte L.The circuits that allow organisms to control behavioral timing need to be tightly regulated to ensure execution of appropriate environmental responses. Disrupting such regulation results in individuals unable to perform tasks necessary for survival and propagation. Identifying the molecular components regulating behaviors will enable compensation where behavioral impediments to survival exist. To identify circuits of behavioral regulation, I studied male mating behavior in the nematode Caenorhabditis elegans. Specifically, I focused on the step wherein the male inserts his copulatory spicules into the hermaphrodite vulva, as vulva penetration is required for successful sperm transfer. This step must be tightly regulated; if the spicules protract too soon or not at all, vulva penetration and thus successful mating will not occur. In this dissertation, I elucidate the circuits regulating sex-muscle excitability under standard conditions and describe how these pathways are augmented to further reduce excitability under food deprivation conditions. I employ a variety of assays to identify and analyze these circuits, including genetic manipulation, biochemical techniques, and behavioral assays. Under standard conditions the calcium/calmodulin-dependent protein kinase II (CaMKII) encoded by unc-43 is required to inhibit C. elegans male sex-muscle seizures; under conditions where food is scarce, I propose that CaMKII is further up-regulated to activate the EAG K+ channel EGL-2 through a direct interaction. The CaMKII/EGL-2 interaction functions to attenuate calcium influx from L-type voltage-sensitive calcium channels (L-VGCCs), while CaMKII also downregulates calcium influx from ryanodine receptors. Additionally, another K+ channel, the voltage- and calcium-sensitive big current channel SLO-1, attenuates sex-muscle excitability by inhibiting L-VGCCs under food deprivation conditions. In conclusion, CaMKII and EGL-2?s paralog, UNC-103/ERG-like K+ channel, are required when food is plentiful to prevent premature sex-muscle contractions, while food deprivation reduces cell excitability and thereby inhibits inappropriate seizures through CaMKII, EGL-2, and SLO-1.Item Contrasting survival strategies of hatchery and wild red drum: implications for stock enhancement(2009-05-15) Beck, Jessica LouisePost-release survival of hatchery fishes is imperative to the success of any supplemental stocking program. The purpose of this research was to identify differences between hatchery and wild red drum (Sciaenops ocellatus) and determine if pre-release exposure techniques improve survival of hatchery individuals. Objectives were to contrast survival skills of hatchery and wild red drum from different locations, and examine if exposure to natural stimuli (e.g., habitat, predators, live prey) enhances survival skills in na?ve hatchery red drum. Laboratory trials using high-speed videography (250 frames per second, fps) and field mesocosm experiments were used to investigate differences in prey-capture (e.g., attack distance, mean attack velocity, capture time, maximum gape, time to maximum gape, gape cycle duration, and foraging behaviors) and anti-predator performance (e.g., reaction distance, response distance, maximum velocity, time to maximum velocity, mean acceleration, and maximum acceleration) of hatchery and wild red drum. Results indicated that anti-predator performance measures differed significantly between hatchery and wild red drum. Variability in prey-capture and anti-predator performance for hatchery and wild red drum was high (CV range: 5.6 ? 76.5%), and was greatest for hatchery fish for the majority of performance variables tested. Exposure to habitat (Spartina alterniflora marsh) did not appear to afford any obvious survival benefits to hatchery red drum, although survival skills did vary according to ontogenetic stage. Hatchery red drum exposed to natural predators (pinfish, Lagodon rhomboides) exhibited significantly greater attack distances during feeding events, and anti-predator performance variables were 20 ? 300% in these individuals versus na?ve red drum. In predation experiments with free-ranging pinfish predators, mortality rates (Z) ranged from 0.047 ? 0.060 h-1 ? predator-1; however no significant differences in mortality were found between fish reared with and without predators. Hatchery red drum reared on live prey (Artemia franciscana, mysid shrimp) demonstrated enhanced prey-capture and foraging behaviors as well as anti-predator performance relative to fish reared on artificial (pellet) diets. Findings of this research indicate that several behavioral patterns differed between hatchery and wild red drum; however, these differences can be mediated through the use of various pre-release exposure techniques.Item Effects of Habitat, Nest-site Selection, and Adult Behavior on Black-capped Vireo Nest and Fledgling Survival(2012-10-19) Pope, TheresaMany factors affect the productivity of songbirds. Which vegetation types the birds inhabit, nest-site characteristics, and adult behavior at the nest may affect predation and parasitism frequencies, fecundity, and nest survival and fledgling survival. All of these metrics determine reproductive success of individuals and may influence population persistence, especially for threatened and endangered species. My research investigated factors that affected these metrics for endangered black-capped vireos (Vireo atricapilla). Shrubland is considered high quality vireo habitat, with woodland vegetation types considered marginal. I located and monitored nests, conducted nest behavior observations, recorded behavior and predation at nests using video cameras, and resighted fledglings in shrubland, oak-juniper woodland, and deciduous woodland during the 2008?2010 breeding seasons. I monitored 302 black-capped vireo nests in 259 territories and resighted 350 fledglings with unique color combinations. Apparent nest success, nest survival, success of first nest attempts, parasitism and predation frequency, and fecundity did not differ statistically among vegetation types. Parasitism frequency was nearly twice as high in shrubland (22 percent) than in either woodland (12 percent in each) and varied by year. Nest-site characteristics differed among vegetation types, but nest survival was affected only by nest height and year; nests placed higher from the ground and nest attempts in 2008 and 2009 had lower survival. Fledgling survival was not affected by vegetation type or proximity of the nest to oak-juniper woodland. Nest behavior was not affected by vegetation characteristics, though nest attentiveness during incubation increased as average cover from 0 to 2 m increased. Females spent 80 percent more time on nests during incubation and 250 percent more time on nests during the nestling stage than males, but visitation was similar for each sex. Overall, the probability of nest success improved as male participation increased. My results emphasize the importance of male participation in determining the outcome of nests for species exhibiting bi-parental care. Furthermore, woodland habitats previously considered marginal may be good quality habitat in areas with large populations of black-capped vireos. Recognizing woodlands as non-typical, yet still suitable, habitat will allow managers to incorporate these vegetation types into management plans and recommendations for landowner conservation incentive programs.Item Exploring the factors associated with preconception health behaviors among women of childbearing age: a naturalistic inquiry(2009-05-15) Delissaint, DieulaPoor maternal health is one of the major risk factors related to adverse birth outcomes. Women entering pregnancy with poor health status are at higher risk of these outcomes. Prenatal care has been established as the standard prevention paradigm to reduce poor pregnancy outcomes. However, public health professionals are realizing that prenatal care alone is not sufficient to improve perinatal health and birth outcomes, and instead have emphasized the importance of preconception care (PCC). Evidence-based studies reveal that those who received PCC services have better pregnancy outcomes than those who did not. Most published research on preconception are clinical studies, little is known about women?s perception of preconception health and decision-making factor(s) to engage in preconception health practices. Existing research on preconception health behaviors have used retrospective designs, making them difficult to use in assessing the extent of women?s understanding of preconception health behaviors and its relationship to the practice of these behaviors. Thus, an exploratory qualitative study was needed to examine factors associated with preconception health behaviors. The objective of this study was to answer two research questions: (a) What are childbearing age women?s knowledge, beliefs, and perceptions of preconception health/care and how do these factors influence their preconception health behavior? (b) What are the perceived factors (facilitators and hindrances) associated with these women?s intention and decision-making regarding preconception health behaviors? Thirteen women were interviewed about their knowledge and perceptions about PCC and intention toward preconception health behavior practice. The results indicated that women believed PCC is important?using the analogy of preparing their house [body] for conception. Participants associated PCC with physical and nutritional behavior; few acknowledged the importance of mental health. While women believed PCC was important, the majority did not intend to engage in PCC until they became pregnant. The main motivator to engage in PCC was pregnancy. Self-described ?laziness? was the most common reported perceived barrier to PCC. Implications of this study are that additional studies with improved designs are needed to clarify relationships among intentions and actual behaviors, and that health educators should focus on educating women about the importance of self-care before conception.Item Fission-fusion sociality in dusky dolphins (Lagenorhynchus obscurus), with comparisons to other dolphins and great apes(Texas A&M University, 2008-10-10) Pearson, Heidi ChristineI examined fission-fusion sociality in dusky dolphins (Lagenorhynchus obscurus), and investigated aspects of social convergence between dolphins and great apes. I used boat-based group focal follows and photo-identification to collect data in Admiralty Bay, New Zealand during 2005-2006. I used generalized estimating equations to examine relationships between party (group) size, rate of party fission-fusion, activity, and location; and relationships between leaping frequency and behavior. Using photo-identification images from 2001-2006, I analyzed the strength and temporal patterning of associations, short- and long-term association patterns, preferred/avoided associations, and behaviorally-specific preferred associations. To analyze social convergence between dolphins and great apes, I compared female bottlenose dolphin (Tursiops spp.) and chimpanzee (Pan troglodytes) social strategies through literature review. I conducted 171 group focal follows, totaling 157 observation hours. Mean party size was 7.0?6.0 individuals. Party size changed every 5?.47.6 min on average. The most frequent activity was resting (37%), followed by traveling (29%), foraging (18%), and socializing (15%). Foraging was positively related to party size and rate of fission-fusion. Near mussel farms, foraging increased, traveling decreased, and rate of party fusion increased. "Clean" leaps were the most frequent leap type (84%) and were positively related to party size and foraging. Noisy and coordinated leaps were positively related to party size; noisy leaps were negatively related to foraging. Associations during 2001-2006 (N = 228 individuals) were nonrandom for 125 days; associations within one field season were nonrandom for 60 days. Individuals formed preferred/avoided associations during most years. The strongest associations occurred during foraging and socializing; the weakest associations occurred during traveling. Individuals formed preferred associations during foraging, resting, and socializing. Review of female bottlenose dolphin and chimpanzee sociality revealed that: 1) females form weaker bonds and are less social than males, 2) females associate mostly with other females, 3) mothers are often alone with their offspring, 4) mothers (vs. non-mothers) and non-cycling (vs. cycling) females associate less with males, and 5) non-cycling (vs. cycling) females occur in smaller parties. Female dolphins may be more social than female chimpanzees due to decreased scramble competition, increased predation risk, and decreased cost of transport for dolphins vs. chimpanzees.Item Fitting It All Together: How Courtship- and Mating-Responsive Genes Affect Drosophila melanogaster Male Behavior(2011-10-21) Ellis, Lisa LynnBehavior is a complex process resulting from the integration of genetic and environmental information. Thus, the genetically tractable Drosophila melanogaster was utilized to better understand the interplay between these factors since Drosophila males and females exhibit sex-specific courtship behaviors that are innate yet modifiable. These sex-specific behaviors, as well as sexually dimorphic development, are regulated, in part, by the somatic sex-determination hierarchy. Since reproductive behaviors rely on the rapid integration of multiple sensory cues, it is likely that the perception and integration of such cues and mating-induced physiological changes are mediated in part by changes in gene expression. Therefore, it was hypothesized that assaying gene expression changes in response to courtship or mating in Drosophila males would uncover new targets of the sex-determination hierarchy and other behaviorally important loci. We took a novel approach to find these behaviorally-responsive loci by utilizing microarray technology to assess courtship- or mating-induced gene expression changes in Drosophila male whole bodies or heads. Mutations in candidate loci were tested for effects on reproductive behaviors and present the first data showing that egghead (egh) and female-specific independent of transformer (fit) affect male reproductive behavior. egh is up regulated in male heads 20 min after courting and is required post-developmentally in a subset of neurons for robust male courtship behavior. fit, a fat body-expressed sex-determination hierarchy target gene, is up regulated in male whole bodies after 5 min of courtship. fit is also up regulated in male heads after 20 min of courtship or 2 hrs after mating. Mutations in fit result in male-male courtship; more specifically, fit mutants direct courtship towards males and also elicit courtship from wild-type males. By analyzing fit's role in courtship behavior, we also shed light on the role the fat body plays in modulating behavior. These studies provide the first pieces of evidence that gene expression changes occur in Drosophila males performing reproductive behaviors. This novel approach identified behaviorally important loci that are expressed in the nervous system and the fat body, indicating that both tissues modulate behavior. Also identified were sex-determination hierarchy target genes and it is likely that further analysis of the remaining candidates will reveal more members of this genetic cascade.Item Mechanisms and Genomic Patterns of Reproductive Isolation in Xiphophorus Fishes(2014-04-14) Cui, RongfengLearned mate choice has a fundamental role in population dynamics and speciation. Social learning plays a ubiquitous role in shaping how individuals make decisions. Learning does not act on a blank slate, however, and responses to social experience depend on interactions with genetically-specified substrates ? the so-called ?instinct to learn?. I develop a new software Admixsimul, which allows forward-time simulations of neutral SNP markers and functional loci, mapped to user-defined genomes with user-specified functions that allow for complex dominance and epistatic effects. Complex natural and sexual selection regimes (including indirect genetic effects) are available through user-defined, arbitrary fitness and mate-choice probability functions. Using simulation, I show that responses to learned stimuli can evolve to opposite extremes in the context of mating decisions, with choosers either preferring or avoiding familiar social stimuli, depending on the relative importance of inbreeding avoidance versus conspecific mate recognition. I also show that under certain scenarios, learned preference is sufficient to maintain reproductive isolation during secondary contact. Two sister species of swordtail fish have evolved such opposite responses to learned social stimuli. The interaction of learned and innate inputs in structuring mate-choice decisions can explain variation in genetic admixture in natural populations. Olfactory preference of X. malinche females is affected by previous experience with adult cues. I compare gene expression levels of transcriptome libraries prepared from pooled sensory and brain tissues between 3 treatment groups that differ by social experience. I found genes involved in neural plasticity differentially expressed not only between control and exposure groups, but also between groups exposed to conspecific and heterospecific models. I also found evidence that certain vomeronasal receptor type 2 (V2R) paralogs may detect species-specific pheromone components and show differential expression between treatment groups. I then reconstruct evolutionary relationships among swordtails and platyfishes (Xiphophorus: Poeciliidae). Using genomic data, I resolve a high-confidence species tree of Xiphophorus that accounts for both incomplete lineage sorting and hybridization. The results allow me to re-examine a long-standing controversy about the evolution of the sexually selected sword in Xiphophorus, and demonstrate that hybridization has been strikingly widespread in the evolutionary history of this genus.Item Social organization of the New Zealand dusky dolphin(Texas A&M University, 2004-09-30) Markowitz, Timothy MichaelSocial organization of dolphins in extensive societies has not been well studied. Off Kaikoura, New Zealand, thousands of dusky dolphins (Lagenorhynchus obscurus) gather, feeding nocturnally on deep scattering layer prey, resting and socializing diurnally. During 1997-2003, interval sampling was used to monitor large assemblages numbering hundreds (n=169), smaller mating groups (mean+s.e.=7+1.6 adults, n=42), mother-calf nurseries (mean+s.e.=13+1.6 adults, 1+0.5 juveniles, 4+0.7 calves and 1+0.4 neonates, n=41), and non-mating adult groups (mean+s.e.= 9+1.3 adults, 1+0.2 juvenile, n=37). Group size, distance from shore (east), ranging along shore (north), traveling, inter-individual distance, and noisy leaping peaked in winter (n=39), with dolphins maintaining closer proximity to each other in smaller, more restful groups, closer to shore during the spring-summer-autumn (n=234) reproductive seasons. Dolphin groups were found closest to shore (west) during early morning, spread out and leaping often. Resting peaked at midday in tight groups. Late in the day, dolphins spread out, moving eastward (offshore) in preparation for feeding. Large groups exhibited coordinated travel, with noisy leaps as a directional signal. "Mating of the quickest" occurred in groups of (median) 6 males chasing 1 female. Leaping rarely occurred in restful nurseries, which at times associated with Hector's dolphins (Cephalorhynchus hectori). Other mixed-species groups included common dolphins (Delphinus delphis), southern right whale dolphins (Lissodelphis peronii), long-finned pilot whales (Globicephala malaena), and bottlenose dolphins (Tursiops truncatus). Killer whales (Orcinus orca) elicited predator assessment and evasion. Whale riding occurred with larger whales. Residence was seasonal, with 1,969+814.9 from a population of 12,626 dolphins spending 103+38.0 days in Kaikoura (mean+s.e., mark-recapture mortality, single-season lagged-ID emigration models, n=153 weeks). Dolphins (n=39) summering in Kaikoura migrated to the Marlborough Sounds in winter, where small, coordinated groups foraged diurnally on schooling fishes in shallow bays, often associated with sea birds and New Zealand fur seals (Arctocephalus forsteri). Aquaculture may threaten dusky dolphin foraging habitat in Admiralty Bay, where an estimated 220 dolphins gathered to feed each winter. Photo-identification research, enhanced by digital techniques, demonstrated a structured fission-fusion society. Dusky dolphins associated with preferred long-term (>1,000 days) hunting companions in Admiralty Bay and non-random casual acquaintances (200 days) in Kaikoura (lagged-association models).Item Spatial and temporal winter territory use and behavioral responses of whooping cranes to human activities(2009-06-02) LaFever, Kristin E.I investigated spatial and temporal winter behavior and behavioral responses of 5 territorial whooping crane families to human activities at Aransas National Wildlife Refuge during winters 2003-2004 and 2004-2005. Adult and juvenile cranes spent the majority of the day foraging (63% and 66%, respectively). Alert behavior comprised 15% of the cranes' time-activity budgets; preening or resting, and movement each constituted approximately 7% of the time-activity budget. Adults were more alert than juveniles in Jan-Feb. The proportion of time spent in other behaviors did not differ by age. Over-winter use of territories varied spatially and temporally. Flight occurrence was highest in Nov-Dec, coinciding with establishment of territorial boundaries upon arrival at the wintering grounds. Movement velocity (meters traveled/min) also tended to be highest in Nov-Dec, which may be due to territorial defense and foraging activities. Use of land, open water, and edge habitats (land and water interface) within territories appeared to fluctuate with primary food item availability. Disproportionate use of land habitat by several crane families coincided with peak production of wolfberry (Lycium carolinianum) fruit, which occurs in Nov-Dec. Edge habitat was used disproportionately to its availability throughout the winter, most likely because this habitat type provided refuge for blue crabs (Callinectes sapidus), an important food item for whooping cranes. Several families also used open water disproportionately to its availability. Behavioral responses of whooping cranes to human activities were limited. Responses to varying frequency and intensity of human stimuli were evaluated. Most stimuli did not elicit a response. Two crane families decreased the proportion of time spent foraging during periods of high-intensity stimuli; one family increased movement during such times. Foraging behavior of one family was significantly higher when stimuli frequency was high; alert behavior significantly declined as stimuli frequency increased. The mixed responses of territorial families to varying levels of human stimuli paired with the overall high level of reproductive success of the entire population led to my conclusion that current levels of human activities are not having a detrimental impact on the Aransas-Wood Buffalo whooping crane population.Item The Effects of Behavioral Monitoring Programs on Reading Acquisition of Elementary Students with or At-Risk for Emotional or Behavioral Disorder(2010-07-14) Morgan, Stacy W.The Behavior Education Program was implemented with four students at a large sub-urban elementary school in central Texas. The elementary school has a diverse population of 750 students and was implementing Tier 1 interventions with 81% fidelity as measured by the School-wide Evaluation Tool. The BEP was implemented in a multiple-baseline design. All students? behavioral improvement was measured through daily behavior rating scales, office discipline referrals and time sampling data. Academic engagement was measured through direct observation, DIBELS progress-monitoring and nine-week grades. Progress on BEP goals was then compared to direct observation data of on-task behavior and DIBELS data. All three students? improvement on BEP goals correlated with an improvement in academic engagement and increased scoring on DIBELS progress monitoring indicating that progress in the area of behavior is linked to academic achievement.Item The influence of contagion information and behavior on older adolescents' perceptions of peers with chronic illness(Texas A&M University, 2005-11-01) Grizzle, Jonhenry CordellTo explore attributions about chronically ill peers, 545 older adolescents ages 17-26 read a short vignette describing a brief social encounter with a hypothetical peer suffering from a medical condition, and then responded to a series of questionnaires to assess their perceptions of that peer. Nine measures intended to assess perceptions of ill peers were developed and empirically validated. Test-retest reliability and internal consistency was moderate to good for all measures. Component structure of the Peer Acceptance Questionnaire (PAQ), Peer Acceptance Questionnaire ?? 3rd Person (PAQ-F), and Perceived Similarity Questionnaire (PSQ) were also evaluated. Principal components analysis yielded a 2-factor structure of Openness and Egalitarianism for both the PAQ and PAQ-F. A 6-factor structure of (a) Familial/Spiritual, (b) General Health, (c) Social, (d) Behavioral, (e) Physical, and (f) Educational was suggested for the PSQ. Results indicated an interaction between illness type and behavior on acceptance ratings, such that behavior potentiated the effect of illness type on acceptance. In addition, vignette characters with contagious illnesses were rated less favorably than those with noncontagious illnesses, and vignette characters displaying typical behavior were rated more favorably than either withdrawn or aggressive vignette characters. Illness-specific knowledge, ratings of perceived similarity, and ratings of assigned blame predicted acceptance ratings, whereas illness-specific knowledge and acceptance ratings predicted ratings of assigned blame. Finally, significant differences were observed between first- and third-person ratings of both acceptance and assigned blame.Item The neuromolecular mechanisms that coordinate food availability with C. elegans male sexual behavior(2009-05-15) Gruninger, Todd RyanOrganisms must coordinate behavioral and physiological responses to changingenvironmental conditions. In the nematode C. elegans, the presence or absence of foodin the environment affects many metabolic and behavioral responses, including fathomeostasis, lifespan, and male mating. Specifically, male mating behavior normallyoccurs when a well-nourished male encounters a hermaphrodite, and is repressed if themale is under-nourished. To understand how environmental changes influence the driveto carry out specific behavioral tasks, I used C. elegans male mating as a model.Previously, mutants were isolated that display male mating behavior at inappropriatetimes, i.e. in the absence of mating cues. Loss of function mutations in the ERG K+channel, UNC-103, results in spontaneous seizures of the male sex muscles.Interestingly, I found that food deprivation can suppress unc-103(lf)-induced seizures,suggesting that pathways activated under this environmental condition can suppress theexcitability of the mating circuit.Using molecular, genetic, and behavioral assays, I identified sensory andmolecular mechanisms that reduce sex-muscle excitability under food-deprived conditions. I found that mutations that affect the muscular feeding organ, the pharynx,phenocopy the effects of food deprivation, and reduce sex-muscle excitability. Idemonstrated that mutations in the pharyngeal muscle protein, tropomyosin, cause thepharyngeal neurosecretory motor neurons (NSMs) to increase pharyngeal excitabilityand reduce sex-muscle excitability. Additionally, I found that olfactory neurons (AWCs)with sensory cilia exposed to the environment are up-regulated in the absence of foodstimuli, and also send inhibitory signals to the sex muscles. To determine howchemosensory and pharyngeal neurons in the head can signal to the genitalia, Ihypothesized that one mechanism could be via secretion of metabolic hormones. To testthis, I examined loss-of-function mutations in the insulin-like receptor, DAF-2, which isknown to regulate many behavioral and physiological responses to food. I demonstratedthat DAF-2 activity in the sex muscles is required for food-deprivation suppression ofunc-103(0)-induced seizures. I then identified components of a novel-insulin-like/DAF-2signaling pathway that reduces excitability. Specifically, I propose that ligand binding toDAF-2 activates PLC- and leads to increased cystolic Ca2+. This Ca2+ influx activatesCaMKII, which can phosphorylate/activate EAG-like K+ channels, thereby reducing cellexcitability.Item The Social Context of Foot-and-Mouth Disease Control in Texas: Foundations for Effective Risk Communication(2012-02-14) Delgado, Amy HaleyThe introduction of FMD into the US would have serious economic and societal effects on the livelihoods and sustainability of affected livestock producers. Livestock producers serve as an important line of defense in both detecting an introduction of FMD as well, helping to prevent disease spread. However, due to the complexity of moral, social, and economic issues surrounding the control of highly contagious diseases, producer cooperation during an outbreak may not be assured. This study was conducted using a mixed-methods approach, including qualitative analysis of interviews and quantitative analysis of a postal survey, in order to explore the factors likely to influence producer cooperation in FMD detection and control in Texas. Reporting of cattle with clinical signs of FMD in the absence of an outbreak was related to producers? beliefs about the consequences of reporting, beliefs about what other producers would do, trust in agricultural agencies, and their perception of the risk posed by FMD. During a hypothetical outbreak, intentions to report were determined by beliefs about the consequences of reporting, and perception of the risk posed by FMD. Intentions to gather and hold cattle when requested during an outbreak were determined by beliefs about the consequences of gathering and holding, beliefs about barriers to gathering and holding, trust in other producers, and perception of the risk posed by FMD. Compliance with animal movement restrictions was determined by experiential attitudes, beliefs about the availability of feed, space, and disinfection procedures, beliefs about what other producers would do, and perception of the risk posed by FMD. Recommendations for improving producer cooperation include targeting specific beliefs in both planning and communication, increasing transparency in the post-reporting process, planning for and communicating plans for maintaining business continuity in order to better inform risk perception, and partnering with organizations to ensure sustained and meaningful communication that supports trust between producers within the affected agricultural community.Item Western Gray Whale (Eschrichtius robustus) Mother and Calf Ecology Off Sakhalin Island(2012-07-16) Sychenko, Olga AleksandrovnaThe western population of gray whales (Eschrichtius robustus) is endangered with approximately 130 individuals remaining. Many individuals return annually to the same feeding sites off northeastern Sakhalin Island, indicating a site-specific dependence to this geographic area. This apparently critically important habitat is especially vital for nursing females and their calves, as female energetic requirements are increased during lactation, and calves need to be ready to separate and begin to feed on their own. This study focuses on movements, respirations and behavioral patterns of mother/calf pairs on their feeding ground, with data collected during summer-autumn of 2002-2009. Shore-based observations included three methods: theodolite tracking, focal-animal behavior sampling, and photo-identification. Whales were categorized as three groups of individuals: mother/calf pairs, weaned calves, and other individuals. Analyses were performed to assess differences between groups of individuals, and in relation to their behavior. The null hypothesis of the study was that there were no differences in movement/respiration/behavioral patterns and habitat use between different groups of individuals. Results did not support this hypothesis. Significant differences in movements and respirations were found for certain groups of individuals. These differences also varied in relation to the whales' behavioral activity (feeding, feeding/traveling, and traveling). The shore-based photography was used to obtain additional information on individuals (especially mother/calf pairs) and their sightings, as well as to evaluate the success of this approach. A total of 144 individuals, including 10 females (sighted with calves) and 31 calves were identified during 2004-2009. The shore-based photo-identification approach was successful, and due to being a non-invasive technique, is recommended as a supplemental approach to vessel-based photo-ID efforts. Reproductive success and survival of western gray whales are concern especially due to the presence of industrial activity in the area, as well as recently increased mortalities of female gray whales off Japan. Therefore, the results of this study indicate the importance of considering differences in needs and habitat utilization of different groups of individuals for basic science information as well as for management purposes of protection of western gray whales.