Matching Items (76)
Description
When ants encounter liquid food, they have two options of transporting that food to their nests. The first is the social bucket method in which liquid is carried in the mandibles of the workers back to the nest. The second is trophallaxis in which liquid is imbibed and then transported inside the ant back to the nest. The liquid is then regurgitated to fellow nestmates. Ectatomma have been observed using the social bucket method of transport and were considered members of the Ponerine family. However, a new phylogeny created by Borowiec and Rabeling places Ectatomma near to Formecinae and Myrmicinae, both know for practicing trophallaxis. This seems to suggest either Ectatomma is able to utilize trophallaxis as well or that the evolutionary practice of trophallaxis is more plastic than previously believed. The ability of Ectatomma ruidum to utilize trophallaxis was examined in two experiments. The first experiment examined E. ruidum’s ability to practice worker to worker trophallaxis and the second examined E. ruidum’s ability to perform worker to larva trophallaxis. The results of both experiments indicated that E. ruidum cannot utilize trophallaxis but the larva of E. ruidum may be able to regurgitate to the workers. These results in turn seem to suggest that trophallaxis is a bit more plastic than originally thought.
ContributorsCunningham, Cassius Alexander (Author) / Pratt, Stephen (Thesis director) / Liebig, Juergen (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
An intimate view of the unique architecture of Harpegnathos saltwater nest using aluminum nest casts
Description
Abstract:
Given the incredible variety in ant nest architecture, this experiment sought to evaluate how the nest architecture of Harpegnathos saltator differs from other species’ nests. To achieve the ability to evaluate the structure of H. saltator nest, we created experimental colonies varying in size from 20, 40, 60, 80 workers of Harpegnathos saltator in five-gallon buckets of sand and then allowing the colonies to grow for four months and twelve days. To create the nest casts, we developed a charcoal kiln out of a galvanized trash can and used a ceramic crucible to hold the aluminum being melted. Using molten aluminum to create nest casts of each colony produced, we obtained three poorly developed nests and one decent nest. The decent nest cast, the 80 worker H. saltator nest, was lacking key features of H. saltator nests that have been excavated in the field. However, they do share many of the same structures such as the shaping of the chambers. The ability of the experimental colonies to excavate the soil provided in the buckets to them was likely halted by poor penetration of water into superficial layers of the soil, thus making the soil too difficult to excavate and form the structures that are key elements of the species nest architecture. Despite these key challenges which the colonies faced, the 80-worker colony showed extensive vertical development and did display features associated with natural H. saltator colonies. Thus, given the display of some key features associated with characteristics of the H. saltator nests excavated in the field, it can be said that with some modification to technique that this is a viable avenue for future study of nest architecture and colony structure.
Given the incredible variety in ant nest architecture, this experiment sought to evaluate how the nest architecture of Harpegnathos saltator differs from other species’ nests. To achieve the ability to evaluate the structure of H. saltator nest, we created experimental colonies varying in size from 20, 40, 60, 80 workers of Harpegnathos saltator in five-gallon buckets of sand and then allowing the colonies to grow for four months and twelve days. To create the nest casts, we developed a charcoal kiln out of a galvanized trash can and used a ceramic crucible to hold the aluminum being melted. Using molten aluminum to create nest casts of each colony produced, we obtained three poorly developed nests and one decent nest. The decent nest cast, the 80 worker H. saltator nest, was lacking key features of H. saltator nests that have been excavated in the field. However, they do share many of the same structures such as the shaping of the chambers. The ability of the experimental colonies to excavate the soil provided in the buckets to them was likely halted by poor penetration of water into superficial layers of the soil, thus making the soil too difficult to excavate and form the structures that are key elements of the species nest architecture. Despite these key challenges which the colonies faced, the 80-worker colony showed extensive vertical development and did display features associated with natural H. saltator colonies. Thus, given the display of some key features associated with characteristics of the H. saltator nests excavated in the field, it can be said that with some modification to technique that this is a viable avenue for future study of nest architecture and colony structure.
ContributorsAnderson, Clayton Edward (Author) / Liebig, Juergen (Thesis director) / Pratt, Stephen (Committee member) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Complex animal societies consist of a plethora of interactions between members. To successfully thrive they must be able to recognize members and their kin, and to understand how they do this we need sufficient and reliable methods of testing. Eusocial insects are especially good at recognizing their nestmates, but the exact mechanism or how well they can discriminate is unknown. Ants achieve nestmate recognition by identifying varying proportions of cuticular hydrocarbons. Previous studies have shown ants can be trained to discriminate between pairs of hydrocarbons. This study aims to compare two methodologies previously shown to demonstrate odor learning to identify which one is the most promising to use for future odor learning experiments. The two methods tested were adapted from Sharma et al. (2015) and Guerrieri and d’Ettorre (2010). The results showed that the Guerrieri method demonstrated learning better and was more reliable and faster than the Sharma method. The Guerrieri method should be used in future experiments regarding odor learning discrimination
ContributorsDavis, Cole (Author) / Liebig, Juergen (Thesis director) / Stephen, Pratt (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
In response to a national call within STEM to increase diversity within the sciences, there has been a growth in science education research aimed at increasing participation of underrepresented groups in science, such as women and ethnic/racial minorities. However, an underexplored underrepresented group in science are religious students. Though 82% of the United States population is religiously affiliated, only 52% of scientists are religious (Pew, 2009). Even further, only 32% of biologists are religious, with 25% identifying as Christian (Pew, 2009; Ecklund, 2007). One reason as to why Christian individuals are underrepresented in biology is because faculty may express biases that affect students' ability to persist in the field of biology. In this study, we explored how revealing a Christian student's religious identity on science graduate application would impact faculty's perception of the student during the biology graduate application process. We found that faculty were significantly more likely to perceive the student who revealed their religious identity to be less competent, hirable, likeable, and faculty would be less likely to mentor the student. Our study informs upon possible reasons as to why there is an underrepresentation of Christians in science. This further suggests that bias against Christians must be addressed in order to avoid real-world, negative treatment of Christians in science.
ContributorsTruong, Jasmine Maylee (Author) / Brownell, Sara (Thesis director) / Gaughan, Monica (Committee member) / Barnes, Liz (Committee member) / School of Life Sciences (Contributor) / W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
For colonies of ponerine ant species, sterility regulation after a founding queen's death is not totally achieved in the worker caste, and the possibility of sexual reproduction is opened to workers. The persisting survival of these colonies is dependent on capturing the optimal reproductive ratio; yet, an informational gap bounds the mechanisms detailing the selection of new reproductives and the suppression of ovarian development in rejected reproductives. We investigated the mechanisms of worker policing, one of the primary methods of ovarian suppression, through continuous video observation for a period of five days at the start of colony instability. Observations suggest policing in H. saltator is performed by a majority of a colony, including potential reproductives, and requires multiple events to fully discourage ovarian growth.
ContributorsChien, Jeffrey (Co-author) / Barat Ali, Fatima (Co-author) / Kang, Yun (Thesis director) / Liebig, Juergen (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
Due to the widely accepted trend of urbanization displacing wildlife from their natural habitats and niches, many wildlife conservation organizations have sprouted up, even in Phoenix. Liberty Wildlife Foundation is one that rehabilitates avian wildlife. Several studies have mentioned an opposing theory: that urbanization helps conserve those species that have turned urban environments into a niche of their own. Since these wildlife conservation centers are localized in cities themselves, this brings into question these organizations' definitions of the term "wildlife." This study examined injury and recovery statistics to determine just how many of the patients admitted were conventional wildlife versus urban-dwelling city birds, and whether this classification had any effect on their likeliness of recovery and release. The data showed that out of over 130 species, a few key urban species contributed to an overwhelmingly large majority of injured birds admitted to the center in 2017; urban and non-urban birds, however, had relatively equal average release frequencies, demonstrating then that their likelihood of recovery was predominantly dependent on the injury borne by them.
ContributorsVirdee, Rishika Kaur (Author) / Liebig, Juergen (Thesis director) / Lynch, John (Committee member) / Haight, Kevin (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Learning student names has been promoted as an inclusive classroom practice, but it is unknown whether students value having their names known by an instructor. We explored this question in the context of a high-enrollment active-learning undergraduate biology course. Using surveys and semistructured interviews, we investigated whether students perceived that instructors know their names, the importance of instructors knowing their names, and how instructors learned their names. We found that, while only 20% of students perceived their names were known in previous high-enrollment biology classes, 78% of students perceived that an instructor of this course knew their names. However, instructors only knew 53% of names, indicating that instructors do not have to know student names in order for students to perceive that their names are known. Using grounded theory, we identified nine reasons why students feel that having their names known is important. When we asked students how they perceived instructors learned their names, the most common response was instructor use of name tents during in-class discussion. These findings suggest that students can benefit from perceiving that instructors know their names and name tents could be a relatively easy way for students to think that instructors know their names. Academic self-concept is one's perception of his or her ability in an academic domain compared to other students. As college biology classrooms transition from lecturing to active learning, students interact more with each other and are likely comparing themselves more to students in the class. Student characteristics, such as gender and race/ethnicity, can impact the level of academic self-concept, however this has been unexplored in the context of undergraduate biology. In this study, we explored whether student characteristics can affect academic self-concept in the context of a college physiology course. Using a survey, students self-reported how smart they perceived themselves in the context of physiology compared to the whole class and compared to the student they worked most closely with in class. Using logistic regression, we found that males and native English speakers had significantly higher academic self-concept compared to the whole class compared with females and non-native English speakers, respectively. We also found that males and non-transfer students had significantly higher academic self-concept compared to the student they worked most closely with in class compared with females and transfer students, respectively. Using grounded theory, we identified ten distinct factors that influenced how students determined whether they are more or less smart than their groupmate. Finally, we found that students were more likely to report participating less than their groupmate if they had a lower academic self-concept. These findings suggest that student characteristics can influence students' academic self-concept, which in turn may influence their participation in small group discussion.
ContributorsKrieg, Anna Florence (Author) / Brownell, Sara (Thesis director) / Stout, Valerie (Committee member) / Cooper, Katelyn (Committee member) / School of Life Sciences (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Insects have intricate systems they depend on for survival. They live in societies where every individual plays an important role. Ants are a great example of this observation. They are known for having structurally sound societies that ensure the livelihood of the colony. The ant species analyzed for this research, Harpegnathos saltator, portrays a structured colony and serves as a useful example of levels of hierarchy. In the colony of H. saltator, one can find a queen, gamergates, workers, and male ants living underground in Southern India. Recording and analyzing egg-laying rates are important in this study because of the amount of information it provides. It is used especially when observing the relationship among the gamergates in colonies with varying colony sizes. Three different methods were used to record the egg-laying rates, each providing insight into valuable information. Results show that the smaller colonies with fewer identified gamergates do share an equal amount of egg-laying. In larger colonies, it appears that there are more active identified gamergates than others. Egg-laying duration times are smaller in colonies with fewer gamergates. It is also found that the presence of brood does not affect egg-laying rates and reproductive inhibition could be a possibility based on two of the colonies observed F65 and F21. Based on the data found, a more active colony that attempts to maintain stability by demonstrating aggression may be affecting the reproduction of gamergates. Future work that would further strengthen the research and conclusions made would involve further observation of colonies, both large and small, with varying numbers of gamergates. More observation involving behavior among gamergates and workers would also be beneficial. Mathematical modeling could also be incorporated to create equations that could determine information about colonies based on size, number of gamergates, and egg-laying rates.
ContributorsMayoral, Alejandra (Author) / Kang, Yun (Thesis director) / Liebig, Juergen (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Course-Based Undergraduate Research Experiences, or CUREs have become an increasingly popular way to integrate research opportunities into the undergraduate biology curriculum. Unlike traditional cookbook labs which provide students with a set experimental design and known outcome, CUREs offer students the opportunity to participate in novel and interesting research that is of interest to the greater biology community. While CUREs have been championed as a way to provide more students with the opportunity to experience, it is unclear whether students benefit differently from participating in different CURE with different structural elements. In this study we focused in on one proposed element of a CURE, collaboration, to determine whether student's perception of this concept change over the course of a CURE and whether it differs among students enrolled in different CUREs. We analyzed pre and post open-ended surveys asking the question "Why might collaboration be important in science?" in two CUREs with different structures of collaboration. We also compared CURE student responses to the responses of senior honors thesis students who had been conducting authentic research. Five themes emerged in response to students' conceptions of collaboration. Comparing two CURE courses, we found that students' conceptions of collaboration were varied within each individual CURE, as well as what students were leaving with compared to the other CURE course. Looking at how student responses compared between 5 different themes, including "Different Perspectives", "Validate/Verify Results", "Compare Results", "Requires Different Expertise", and "Compare results", students appeared to be thinking about collaboration in distinct different ways by lack of continuity in the amount of students discussing each of these among the classes. In addition, we found that student responses in each of the CURE courses were not significantly different for any of the themes except "Different Expertise" compared to the graduating seniors. However, due to the small (n) that the graduating seniors group had, 22, compared to each of the CURE classes composing of 155 and 98 students, this comparison must be taken in a preliminary manner. Overall, students thought differently about collaboration between different CUREs. Still, a gap filling what it means to "collaborate", and whether the structures of CUREs are effective to portray collaboration are still necessary to fully elaborate on this paper's findings.
ContributorsWassef, Cyril Alexander (Author) / Brownell, Sara (Thesis director) / Stout, Valerie (Committee member) / Cooper, Katelyn (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Insects are able to navigate their environments because they can detect hydrocarbons and volatile odors, but it is not clear which one has the fastest reaction when detected, or how much of a response can be produced due to either one. In order to determine which category of odorant is detected first as well as which one causes the highest response rate, data on electrophysiological responses from ants was analyzed. While the statistical tests can be done to understand and answer the questions raised by the study, there are various hydrocarbons and volatile odors that were not used in the data. Conclusive evidence only applies to the odorants used in the experiments.
ContributorsDarden, Jaelyn (Author) / Gerkin, Richard (Thesis director) / Liebig, Juergen (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05