Matching Items (7)
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- All Subjects: Temnothorax
- All Subjects: conservation
- Creators: Pratt, Stephen
Description
Collective decision making in social organism societies involves a large network of communication systems. Studying the processes behind the transmission of information allows for greater understanding of the decision making capabilities of a group. For Temnothorax rugatulus colonies, information is commonly spread in the form of tandem running, a linear recruitment pattern where a leading ant uses a short-ranged pheromone to direct a following ant to a target location (in tandem).The observed phenomenon of reverse tandem running (RTR), where a follower is lead from a target back to the home nest, has not been as extensively studied as forward tandem running and transportation recruitment activities. This study seeks to explain a potential reason for the presence of the RTR behavior; more specifically, the study explores the idea that reverse tandem run followers are being shown a specific route to the home nest by a highly experienced and efficient leading ant. Ten colonies had migrations induced experimentally in order to generate some reverse tandem running activity. Once an RTR has been observed, the follower and leader were studied for behavior and their pathways were analyzed. It was seen that while RTR paths were quite efficient (1.4x a straight line distance), followers did not experience a statistically significant improvement in their pathways between the home and target nests (based on total distance traveled) when compared to similar non-RTR ants. Further, RTR leading ants were no more efficient than other non-RTR ants. It was observed that some followers began recruiting after completion of an RTR, but the number than changed their behavior was not significant. Thus, the results of this experiment cannot conclusively show that RTR followers are utilizing reverse tandem runs to improve their routes between the home and target nests.
ContributorsColling, Blake David (Author) / Pratt, Stephen (Thesis director) / Liebig, Juergen (Committee member) / Sasaki, Takao (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-12
Description
Conservation is a complicated entity consisting of a multitude of professional fields including social issues, cultural issues, and physical science. This thesis evaluates the positive and negative aspects of two broad types of conservation: top down fortress conservation and bottom up community-based conservation. Fortress conservation has many negative aspects, such as displacing human communities and preventing utilization of resources. However, it also has positive aspects, such as preventing the destruction of delicate ecosystems and slowing down extinctions. Community-based conservation is more inclusive and focuses on including the indigenous populations located within the proposed conservation site in the decision-making process. Its negatives include having an anthropocentric goal instead of valuing nature's intrinsic values. Understanding the differences inherent in these two methods is necessary in order to implement a conservation network with the highest chance for success.
ContributorsFink, Laurel Berylline (Author) / Smith, Andrew (Thesis director) / Collins, James (Committee member) / Minteer, Ben (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
Consumption of seafood poses a substantial threat to global biodiversity. Chemical contamination found in both wild-caught and farmed seafood also presents significant health risks to consumers. Flame retardants, used in upholstery, plastics, clothing, and other products to reduce fire danger, are of particular concern as they are commonly found in the marine environment and permeate the tissues of fish that are sold for consumption via multiple pathways. By summarizing various metrics of sustainability and the mercury content in consumed species of fish and shellfish, researchers have found that high levels of chemical contamination was linked with lesser fishery sustainability. I conducted a literature review of flame retardant content in seafood to further compare contamination and sustainability in addition to the initial analysis with mercury. My review suggests that the widespread issue of fishery collapse could be alleviated by demonstrating to stakeholders that many unsustainable fish stocks are mutually disadvantageous for both human consumers and the environment. Future research should address the need for the collection of data that better represent actual global contaminant concentrations in seafood.
ContributorsNoziglia, Andrea Joyce (Author) / Gerber, Leah (Thesis director) / Smith, Andrew (Committee member) / Pratt, Stephen (Committee member) / Barrett, The Honors College (Contributor) / Herberger Institute for Design and the Arts (Contributor) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
Temnothorax rugatulus ants are known to recruit via the use of tandem running, a typically two ant interaction in which a leader ant guides a follower ant to a particular location with the intent of teaching the follower ant the knowledge required to navigate to said location independently. In general, the purposes of tandem runs are fairly clear. There are tandem runs towards food in order to recruit gatherers, and there are tandem runs towards potential new nest sites to allow the colony to assess site quality. However, a group of tandem runs known as “reverse tandem runs” are a subject of mystery at this time. Reverse tandem runs are a type of tandem run found mainly during specific spans of Temnothorax colony migration. They typically arise during the period of migration when brood are being transported into a new nest site. The carriers of the brood, when returning to the old nest site to gather more brood, occasionally start tandem runs running backwards towards the old nest. In this study, the effect of navigational and physical obstacles encountered during migrations on the number of reverse tandem runs was tested. The hypothesis being that such a disturbance would cause an increase in reverse tandem runs as a method of overcoming the obstacle. This study was completed over the course of two experiments. This first experiment showed no indication of the ants having any trouble with the applied disturbance, and a second experiment with a larger challenge for the migrating ants was performed. The results of this second experiment showed that a migration obstacle will lead to an increase in migration time as well as an increase in the number of failed reverse tandem runs (reverse tandem runs that started but never reached the old nest). However, it was shown that the number of complete reverse tandem runs (reverse tandem runs that reached the old nest) remained the same whether the obstacle was introduced or not.
ContributorsKang, Byounghoon (Author) / Pratt, Stephen (Thesis director) / Juergen, Liebig (Committee member) / Valentini, Gabriele (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Current conservation practices are substantially biased towards large, charismatic animals and are influenced by public perceptions of different animals. Therefore, it is important to understand how these perceptions are formed and what factors influence them in order to promote equitable conservation for all species. This study examines the effect of attending a park education program on public values, knowledge of, and attitudes towards a noncharismatic species. Data was collected from May through October 2016 at the Usery Mountain Regional Park "All About Scorpions" program. A four page, onsite, self-administered pre- and post-program survey was given to program attendees. An identical survey was given to hiking park visitors who had never attended the program as the control sample. Survey statements addressed participant's demographics, value of bugs, knowledge about scorpions, and attitudes toward scorpions. Data analysis was completed using paired t-tests to analyze any statistically significant changes in values, knowledge, and attitudes between pre- and post-participants. Independent sample t-tests were used to analyze the same between the control and pre-participants. The results showed no difference in the value of bugs for any of the survey participants. However, the program attendees had more positive attitudes and greater knowledge of scorpions than general park visitors, and attending the program further increased positive attitudes and knowledge. Contributions of the study are twofold: First, the results provide Usery with information regarding the influence of their public programs, along with how these programs can be improved to make a greater impact. Second, findings serve to extend the literature on what alters public perceptions and how educational programs can be used to change the current conservation mindset.
ContributorsKallman, Nicole Marie (Author) / Minteer, Ben (Thesis director) / Budruk, Megha (Committee member) / Pratt, Stephen (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Social insect colonies adeptly make consensus decisions that emerge from distributed interactions among colony members. How consensus is accomplished when a split decision requires resolution is poorly understood. I studied colony reunification during emigrations of the crevice-dwelling ant Temnothorax rugatulus. Colonies can choose the most preferred of several alternative nest cavities, but the colony sometimes initially splits between sites and achieves consensus later via secondary emigrations. I explored the decision rules and the individual-level dynamics that govern reunification using artificially split colonies. When monogynous colonies were evenly divided between identical sites, the location of the queen played a decisive role, with 14 of the 16 colonies reuniting at the site that held the queen. This suggests a group-level strategy for minimizing risk to the queen by avoiding unnecessary moves. When the queen was placed in the less preferred of two sites, all 14 colonies that reunited did so at preferred nest, despite having to move the queen. These results show that colonies balance multiple factors when reaching consensus, and that preferences for physical features of environment can outweigh the queen's influence. I also found that tandem recruitment during reunification is overwhelmingly directed from the preferred nest to the other nest. Furthermore, the followers of these tandem runs had a very low probability (5.7%) of also subsequently conducting transports.
ContributorsDoering, Grant Navid (Author) / Pratt, Stephen (Thesis director) / Pavlic, Theodore P. (Committee member) / Sasaki, Takao (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Aggregation is a fundamental principle of animal behavior; it is especially significant tohighly social species, like ants. Ants typically aggregate their workers and brood in a central nest, potentially due to advantages in colony defense and regulation of the environment. In many ant species, when a colony must abandon its nest, it can effectively reach consensus on a new home. Ants of the genus Temnothorax have become a model for this collective decision-making process, and for decentralized cognition more broadly. Previous studies examine emigration by well-aggregated colonies, but can these ants also reach consensus when the colony has been scattered? Such scattering may readily occur in nature if the nest is disturbed by natural or man- made disasters. In this exploratory study, Temnothorax rugatulus colonies were randomly scattered in an arena and presented with a binary equal choice of nest sites. Findings concluded that the colonies were able to re-coalesce, however consensus is more difficult than for aggregated colonies and involved an additional primary phase of multiple temporary aggregations eventually yielding to reunification. The maximum percent of colony utilization for these aggregates was reached within the first hour, after which point, consensus tended to rise as aggregation decreased. Small, but frequent, aggregates formed within the first twenty minutes and remained and dissolved to the nest by varying processes. Each colony included a clump containing the queen, with the majority of aggregates containing at least one brood item. These findings provide additional insight to house-hunting experiments in more naturally
challenging circumstances, as well as aggregation within Temnothorax colonies.
ContributorsGoodland, Brooke (Author) / Shaffer, Zachary (Thesis advisor) / Pratt, Stephen (Thesis advisor) / Pavlic, Theodore (Committee member) / Arizona State University (Publisher)
Created2023