Visual presentation of information is one method of learning that has the ability to enhance STEM learning compared to learning solely through text. Educational psychology research is ongoing in the STEM field for how students can learn better through visual representations in their course material. The goal of this study was to assess student responses to visual mini-lessons related to course content in the cardiovascular unit in Animal Physiology (BIO360) at Arizona State University. Study participants completed a series of eight mini-lessons and a survey on their experience with the visual lessons. The results of the survey identify increased desire for visual learning materials in STEM courses. The study participants reported that they felt more visual aids in their STEM courses would increase their understanding of course content and that their classroom performance would improve.
Foraging honey bees are challenged to balance the energetic costs of thermoregulating and load-carriage at the same time when flying in hot environments. Honey bees can reduce metabolic rate and wingbeat frequency in response to heat, but the kinematic strategies they use while carrying loads are unknown. I observed honey bees (Apis mellifera) carrying a range of nectar loads (0 to 80% of their own body weight in nectar) when flying at 25 and 40°C air temperatures, and found that hotter honey bees decreased their wingbeat frequency (from 230 to 195 Hz) and increased their stroke amplitude (from 90 to 98°) to generate increasing aerodynamic power as they carry heavier nectar loads. The bees flying at 40°C air temperature carrying heavier loads did increase their wingbeat frequency compared to the unloaded individuals. Despite the kinematic changes, both the hot and cold honey bees were able to generate sufficient power to carry loads of roughly equal mass. Bees flying at 40°C air temperature produced more power than their cooler counterparts, suggesting a more efficient mechanism of load carriage.
In the face of widespread pollinator decline, research has increasingly focused on ways that pesticides could be harming bees. Fungicides are pesticides that are used in greater volumes than insecticides, yet significantly fewer studies have investigated the effects of these agrochemicals. The fungicide Pristine® is commonly used on bee-pollinated crops and has been shown to be detrimental to physiological processes that are key to honey bee foraging, such as digestion and learning. This study seeks to investigate how Pristine® exposure affects the amount of water, nectar, and pollen that honey bees collect. Colonies were fed either plain pollen patties or pollen patties containing 23 ppm Pristine®. Exposure to fungicide had no significant effect on corbicular pollen mass, the crop volumes of nectar or water foragers, or the proportions of foragers collecting different substances. There was a significantly higher sugar concentration in the crop of Pristine®-exposed nectar foragers (43.6%, 95% CI [38.8, 48.4]) compared to control nectar foragers (36.3%, 95% CI [31.9, 40.6]). The higher sugar concentration in the nectar of Pristine®-treated bees could indicate that the agrochemical decreases sucrose responsiveness or nutritional status in bees. Alternatively, fungicide exposure may increase the amount of sugar that bees need to make it back to the hive. Based on these results, it would appear that fungicides like Pristine® do not strongly affect the amounts of substances that honey bees collect, but it is still highly plausible that treated bees forage more slowly or with lower return rates.
Honey Bee (Apis mellifera) populations are being threatened by several environmental stressors. Climate change induced temperature extremes pose a high risk to agriculture and terrestrial ecosystems. Specific threats of climate change affect honey bee brood rearing because honey bee brood need narrow ranges in temperature otherwise there can be negative effects posed on development. Throughout this experiment we tested whether colony size affects thermoregulation. We hypothesized that smaller colonies would struggle to regulate in-hive temperatures in comparison to larger colonies. To test this, temperature loggers were placed in each hive at the brood center, brood edge, and periphery to log temperatures in the summer months of May to September in Arizona. Day and night temperatures were separated for each logger and the average, median, max, and min temperatures were taken for every two-week period wherein the colony population was assessed. For this experiment, we subtracted the min temperature from the max temperature of the final two-week period to assess differences in colony thermoregulatory capability. Overall, smaller colonies struggled to maintain in-hive temperatures in all three areas measured.
modifications to the composite structure of the cuticle in the rostral apex. Finally, interspecific differences in the differential geometry of the snout are characterized to elucidate the role of biomechanical constraint in the evolution of rostral morphology for both males and females. Together these studies highlight the significance of cuticle biomechanics - heretofore unconsidered by others - as a source of constraint on the evolution of the rostrum and the mechanobiology of the genus Curculio.
Before developing a theory for all animals, a model needs to be developed for a single model animal, such as fruit flies, that can be used to empirically examine how organisms thermoregulate under competition. My work examines how flies behave around other flies and develops a game theory model predicting how they should optimally behave. More specifically, my research accounts for competition among larvae by using game theory to predict how mothers should select sites when laying eggs. Although flies prefer to lay their eggs in places that will offer suitable temperatures for the development of their larvae, these sites become less suitable when crowded. Therefore, at some density of eggs, cooler sites should become equally beneficial to larvae when considering both temperature and competition. Given this tradeoff, an evolutionarily stable strategy (ESS) emerges where some flies should lay eggs in cooler sites while other flies should lay eggs at the warmer temperature. By looking at the fitness of genotypes in habitats of differing quality (competition, temperature, food quality, space), I modeled the ESS for flies laying eggs in a heterogeneous environment. I then tested these predictions by observing how flies compete for patches with different temperatures.
Vertebrate studies suggest that surviving anoxia requires the maintenance of ATP despite the loss of aerobic metabolism in a manner that prevents a disruption of ionic homeostasis. Instead, the abilities to maintain a hypometabolic state with low ATP and tolerate large disturbances in ionic status appear to contribute to the higher anoxia tolerance of adults. Furthermore, metabolomics experiments support this notion by showing that larvae had higher metabolic rates during the initial 30 min of anoxia and that protective metabolites were upregulated in adults but not larvae. Lastly, I investigated the genetic variation in anoxia tolerance using a genome wide association study (GWAS) to identify target genes associated with anoxia tolerance. Results from the GWAS also suggest mechanisms related to protection from ionic and oxidative stress, in addition to a protective role for immune function.
