The Asian clam, Corbicula fluminea, is an invasive bivalve species that now occurs through most of the lower 48 United States. While a significant degree of salinity tolerance has been observed in C. fluminea, owing to its estuarine lineage, the physiological and behavioral responses to changes in salinity by these organisms are not completely understood. It was hypothesized that Corbicula would initially avoid elevated salinity levels (>1 g/L) behaviorally through valve closure, but would eventually have to open to dispel anaerobic waste products and deal with the salinity. To explore this, Corbicula were collected and put through a series of experiments at salinity exposures of 0, 2.5, and 5.0 g/L, with tissue water content and hemolymph osmolality being measured. After an initial 96-hour exposure, it was observed that the percent tissue water content of clams in 2.5 g/L and 5.0 g/L water dropped 3.29% and 4.18%, respectively, below that of the control groups in 0 g/L. After a 24-hour time-course experiment, this change in tissue water was found to largely occur within the first eight hours of exposure for the 2.5 g/L and 5.0 g/L groups. It was also noted that the hemolymph osmolality of both the 2.5 g/L and 5.0 g/L groups rose to approximately 78 mOsm/kg and 148 mOsm/kg, respectively, matching the osmolality of their exposure water in roughly the same time span and indicating that little behavioral avoidance of the elevated salinity was occurring. The osmolality of the control group did not match the osmolality of the 0 g/L water at 0.5 mOsm/kg, but was held at a constant level around 50 mOsm/kg. In a later experiment measuring the same variables for clams in 10.0 g/L, it was found that the tissue water and osmolality did not begin to change significantly until after 12 hours, indicating behavioral avoidance at this salinity level. A context study was also conducted comparing oxygen consumption and percent tissue water between various salinities in a light and dark exposure to determine if ambient light influenced siphoning of the clams and exposure to the salt. In this experiment, it was observed that clams held in salinities of 5.0 g/L for 24 hours consumed roughly 1.90 mg O2/L/g/h, whereas clams held in the control only consumed roughly 0.73 mg O2/L/g/h. These findings suggest that Corbicula osmoregulate in freshwater but osmoconform at salinities of 2.5 g/L and 5.0 g/L. The data from the context study also suggests that this conformation comes at a significant metabolic cost. Furthermore, and in contrast to the results of some previous studies, a significant level of behavioral avoidance of elevated salinity does not appear to commence until the clams are at a salinity above 5 g/L.

It has been observed that returning honey bee foragers congregate with unemployed foragers and food receiver bees in a localized region of the hive known as the dance floor. Here, the returning foragers advertise food sources via the waggle dance. It was hypothesized that the close proximity of the dance floor to the hive entrance was related to foragers minimizing time and travel inside the hive. The hive entrance is conventionally located at the bottom of the hive. It was suggested that this location was ideal for easy removal of debris. This correlation between dance floor location and hive entrance location invokes further examination of the relationship. Is the hive entrance location used to establish dance floor location? Using scan sampling- the hive was visually scanned along rows in a descending fashion from the top right corner to hive entrance. The location of each observed waggle dance was recorded for 30 minutes. Observations were conducted for three consecutive days, then the hive entrance location was displaced. The observation hive was altered to contain three hive entrances located adjacent to the bottom first frame, adjacent to the center of the second frame, and adjacent to the middle of the third frame. Only one hive entrance was open at a given time. For the last three days of the experiment, the bottom hive entrance was made accessible again. Regardless of entrance position, the dance floor was seen to be established adjacent to the hive entrance.

Mammals begin learning food preferences in utero and maternally mediated influences early in life help offspring develop their feeding habits. Mammals also learn by individual experience to ingest medicinal compounds such as polyethylene glycol (PEG), which attenuates the negative post-ingestive effects of tannins, a group of potentially toxic plant secondary compounds. The objective of this study was to investigate the transmission of acquired self-medicative behavior from mother to offspring using polyethylene glycol (PEG) as a medicine to relieve malaise caused by tannins. I hypothesized that: 1) mothers trained to associate the beneficial effects of PEG while consuming tannins will pass this information to their offspring, and 2) lambs will be more efficient at utilizing PEG as a medicine against tannins in the presence of mother than lambs which learn without the influence of the mother. This hypothesis was evaluated in four phases: in the first phase, a group of ewes (Experienced) was conditioned to associate the beneficial effects of PEG after consuming a tannin-containing diet. Ewes were offered a meal of high-tannin food and PEG and subsequently, the high-tannin food and grape pomace (GP) with little nutritional and no "medicinal" effects. In the second phase, the experienced and a naïve group of ewes (Inexperienced) were given a choice between the high-tannin food, PEG, and GP. In the third phase, experienced and inexperienced ewes with their naïve lambs, and the group of naïve lambs without their mothers, were exposed to the tannin-containing diet, PEG, and GP. Finally, in the fourth phase, lambs were separated from their mothers, and lambs from all groups were offered a choice between the tannin-containing diet, PEG, and GP. Lambs from experienced and inexperienced mothers showed a higher preference for PEG than lambs exposed without their mothers who tended to show a higher preference for GP. Thus, the presence of mother (experienced/inexperienced) was important for naïve lambs to learn about the medicinal benefits of PEG. This source of trans-generational knowledge could aid in maintaining the information in the herd, increasing the efficiency and reducing the risk of learning about foods and environments exclusively by individual experience.

There is currently a decline in large, old trees within many ecosystems where they play important ecological and economic roles. One ecosystem suffering from this decline is the bushveld savanna of South Africa. One particularly important species in decline is the ecologically, economically, and culturally significant marula tree (Sclerocarya birrea subsp. caffra). This species’ decline is characterized by a steep drop in recruitment of seedlings into the population. Rodents are known to influence plant communities across many ecosystems through herbivory of adult plants as well as predation of seeds and seedlings. This research provides a record of rodent species present in the bushveld savanna ecosystem of Balule Nature Reserve where a decline in marula recruitment is taking place. Further, it offers a summary of morphological statistics and natural history traits for these rodents. Morphological statistics can be used for species identification. Reproductive status of individuals can inform researchers about reproductive phenology and how it may be affected by environmental conditions. Finally, trapping for this study took place during an historic regional drought. Trapping success was used to develop a limited window into how reduced precipitation affects rodent abundances. Morphological traits measured coincide with those available in the literature. Reproductive activity for males and females of one species, Namaqua rock mouse (Micaelamys namaquensis ), did not overlap completely, with females not being reproductively active while males were. Individuals captured and identified as chestnut climbing mice (Dendromus mystacalis) had statistically significantly longer tails and hind feet, and were heavier than reported in reference works.

Invasive species, such as the red lionfish, Pterois volitans, are damaging many ecosystems around the world by out-competing native species. However, little work has been done to determine if P. volitans have a direct influence on the feeding performance of native species with which they compete. This study examines the feeding performance in terms of suction pressure, kinematic timing, and excursion distances of spotted scorpionfish, Scorpaena plumieri. Through multiple trials it was examined how S. plumieri modulate their kinematic behavior in response to P. volitans and a conspecific. The creation of a smaller buccal cavity and a decrease in time of buccal expansion may allow individuals to create greater sub-ambient pressures to increase their prey-capture success. High-speed cinematography and pressure transducers were used to determine if S. plumieri modulate feeding performance in the presence of either P. volitans or a conspecific. The results of the study suggest that S. plumieri do not create larger subambient pressures or modulate their feeding kinematics in the presence of P. volitans or a conspecific.

Escalating human elephant conflict (HEC) continues to be a contributing factor towards elephant decline, and crop raiding is the most common form of negative human-elephant interactions. For communities that cannot reverse or prevent crop raiding, it is necessary to contain HEC events through deterrent measures. Few deterrent measures exist that combine practicality and affordability while also preventing habituation by elephants. This project focused on comparing the efficacy of deterrent methods to assess which was the most successful at preventing elephants from entering crops in the farming community of Sasenyi, Kenya. In this paired-control study, four deterrent methods were evaluated: acacia fences, chili-pepper fences, a new metal strip fence, and a combination of a chili and metal strip fence. Of the over 400 visits by elephants to individual fields containing crops recorded during two field seasons, elephants entered farmer fields in the experimental area on 33 occasions (<10%). Analysis of incidents when elephants approached at less than 50 m revealed that the chili + metal fence and the metal fence were significantly more effective than no deterrent. Following further verification of its effectiveness, this new deterrent method could be a powerful new tool to alleviate elephant crop raiding and reduce HEC.

Sleep is a fundamental and essential component of vertebrate life, although its exact function remains unknown. Animals that are deprived of sleep typically show reduced neurobiological performance, health, and in some cases, survival. However, a number of animals exhibit adaptations that permit them to carry out normal activities even when sleep is restricted or deprived. Lapland longspurs (Calcarius lapponicus), arctic-breeding passerine birds, exhibit around-the-clock activity during their short breeding season, with an inactive period of only 3–4 h/day (71°N). Whether these birds suffer behavioral and physiological costs associated with acute sleep loss (SL) is unknown. To assess the effects of SL, wild-caught male longspurs were placed in captivity (12L:12D) and trained for 2 months using a series of memory tests, including color association and spatial learning to assess executive function. Birds were then placed in automated sleep fragmentation cages that utilize a moving wire to force movement every 1 min (60 arousals/h) during 12D (inactive period) or control conditions (during 12L; active period). After a single round of SL (or control) treatment, color association and spatial learning tests were conducted. Baseline plasma corticosterone concentration, body mass, and satiety were also assessed. SL significantly elevated corticosterone levels and increased accuracy during the color association test, but not the overall time required to complete the test. SL had no effect upon spatial learning, body mass, or satiety. Taken together, these results suggest that Lapland longspurs exhibit a behavioral, but not a physiological, resilience to acute SL.

As charismatic megafauna and a flagship species, African elephants (Loxodonta africana) are vital to the African tourist economy. Conversely, high levels of wildlife tourism can induce behavioral shifts that push desired animals into less frequented areas and disrupt natural behaviors. In order to examine this trade-off, tourism levels and African elephant behaviors were studied in Zambezi National Park (ZNP) near Victoria Falls, Zimbabwe. Over the course of 14 weeks, in-person observations and camera traps in ZNP were used to collect geographic, demographic, and behavioral data from elephant sightings. As a proxy for human presence, geo-locational data were collected for each vehicle sighted in ZNP. These data of vehicles and elephants were mapped in ArcGIS to show a visual representation of their spatial relationship and identify high density and hotspot locations. Analyses from physical observations found that elephants were more frequently sighted in the park region with less vehicle traffic, as expected, but surprisingly also expressed more vigilance behaviors in that region. These results imply that elephants in high traffic regions become accustomed to vehicles but still avoid them when possible. Analyses from camera trap data revealed that only two of the six waterholes monitored had inversely related elephant and human presence, as predicted. There was no clear relationship between elephant and human presence. Future studies should account for habitat type differences in behavioral observations and compare elephant waterhole use in more heavily visited parks.

Investigating how and why individuals interact is an important component to understanding species ecology. The type and patterning of relationships (social structure) provides pertinent insight into how ecological factors such as spatial heterogeneity of resources and predation influence associations between individuals. Many taxa exhibit temporally fluid association patterns, where individuals associate with a variety of others at different rates. Ungulate species exhibit prime examples of highly fluid grouping patterns and individuals form both temporary and long-term associations. The effects of human disturbance on ungulate behavior are well documented and these changes are further exacerbated during the hunting season. Species such as elk (Cervus canadensis) are highly managed having subsistence, recreational, and economic value. The demographic effects of selective take or harvest regimes on population dynamics are known, but how human disturbance, including hunting, influences ungulate social structure on a fine-scale has not been explored. I aimed to investigate the relationship between human disturbance and social structure in a population of elk residing in southeastern, Kentucky, USA. I choose to focus on female elk given the importance of adult female survival to population dynamics and previous knowledge of some social affinity between females. I begin by discussing factors that influence ungulate sociality, how human disturbance can influence sociality and how a better understanding of association patterns could aid in management decisions. I then present two distinct yet vital studies to understanding this relationship: (1) investigation of survival of elk in Kentucky and (2) investigation of association patterns in a human dominated landscape. Hunter harvest is the primary cause of elk mortality in both eastern and western populations in North America and 85.2% of all elk mortalities in Kentucky were hunter harvest related. Older (> 5) males and younger (< 2) females had significantly higher hazards of dying relative to other age classes. Moreover, the establishment of a limited entry hunting area to prevent local overharvest of males had no effect on male survival, but instead may have resulted in local overharvest of females at one site residing on publicly accessible land. Female elk exhibit both weak and strong association patterns. I found that relatedness was significantly greater within sites, similar to patterns found in other cervid species. Association patterns within sites were not explained by age class; and relatedness was only positively correlated at one site. The sites investigated differed in the type and frequency of human disturbance, specifically hunting, suggesting that the disparity in association patterns were driven by these differences. I conclude with two smaller studies, suggesting an indirect consequence of coal surface mining disturbance on ungulate foraging behavior and the potential for interstate transfer of ecto-parasites during reintroduction efforts. This research reinforces previous findings and further refines our understanding of ungulate social structure. Consideration of temporal variation in association patterns of ungulates and other species is important to quantify the effect of disturbance on population and social processes, but also to increase our understanding of dynamic structures. Quantifying the resiliency of structure to disturbance is a priority to further our understanding of the ecology and conservation of these species.

Family-living has been recognized as a necessary prerequisite for the evolution of advanced cooperative societies, yet the evolutionary and ecological processes that drive the coupling of different forms of cooperation in family-based societies are still poorly understood. In my dissertation, I investigate the correlated evolution of parental care, monogamy, and cooperative breeding in a variety of family-based taxa. I explore the mating and social behavior of family-living beetles with incipient cooperation to better understand the factors driving these social traits. Specifically, I evaluate different causes of extra-pair mating in socially monogamous beetles, the potential benefits that young adult offspring may gain from remaining in the family group, and how these behaviors correspond to different ecological niches. These studies demonstrated that many of the factors predicted to favor family-living in cooperatively breeding animals fail to explain delayed dispersal and family cohesion in this beetle group. In a phylogenetic comparative study of birds, I further evaluate how ecological selective pressures drive the correlated evolution of monogamy, biparental cooperation, and cooperative breeding. Taken together, these studies have implications for our general understanding of the evolution of cooperation, and suggest the action of previously unrecognized processes in shaping and pairing social behaviors.