Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-05T19:15:35Z No. of bitstreams: 1 2012 - Luana Priscila de Carvalho Pereira.pdf: 1129568 bytes, checksum: 6b12f4f6e3ee122c2cacabbf7752a126 (MD5) / Made available in DSpace on 2017-04-05T19:15:35Z (GMT). No. of bitstreams: 1 2012 - Luana Priscila de Carvalho Pereira.pdf: 1129568 bytes, checksum: 6b12f4f6e3ee122c2cacabbf7752a126 (MD5) Previous issue date: 2012-06-26 / CAPES / Tropical forests have been recognized as the biome of the planet that has the highest species richness and high endemism. The Amazon forest is part of this scenario and its high diversity has not been fully identified, as well as the patterns that govern it. Although research on the biodiversity of this biome have advanced in recent years, certain groups still have limited knowledge about their geographical and seasonal distribution or even ignored in studies about monitoring, conservation and management. In this sense, the main objective of this study was to determine the composition, richness and rarity of poneromorph ants using different sampling techniques, as well as investigate the effect of seasonality and certain environmental factors in the community. The ants were collected in the National Forest Tapirap?-Aquir? in July 2009, January and July 2010 and January 2011 in three different areas (A1, A2 and A3). In areas A1 and A2 were determined four sampling points inside the forest where they were made two transects of 100 meters and installed every 10 meters a pitfall trap and attractive sardine baits on the undergrowth vegetation and soil. The pitfall was active for 48 hours and baits for an hour. In the A3 was determined only one distance into the woods where it was made the same sampling procedures. We found 46 species of poneromorph ants, belonging to eight genera. The sampling technique that was more effective against the richness of the ant fauna found was the pitfall, which recorded 44 species (95.7% of total) and included all the genera found. Then the bait on the soil showed the richness of 19 species (41.3% of total) and the bait on vegetation presented species richness of six (13% of total). All ants found belong to two sub-families, which were Ponerinae and Ectatominae. The species Gnamptogenys striatula Mayr, and Pachycondyla unidentata 1883 (Mayr, 1862) were found only in the bait on vegetation, they are absent on the ground baits and pitfall throughout sampling. The results for the composition of the poneromorph ant fauna and its seasonal distribution do not show a clear stratification in the community, and the ant species that occurred in the dry and rainy seasons do not form distinct groups in the three sampled areas. Statistical tests to evaluate the influence of environmental variables on the distribution of poneromorfas ants species revealed no association patterns. The identification of the species found has special relevance because contribute to the consolidation of the knowledge of the biodiversity of the Amazon rainforest poneromorfas ants and allow comparative studies with other tropical forest regions. / As florestas tropicais tem sido reconhecidas como o bioma do planeta que possui a maior riqueza de esp?cies, al?m de elevado endemismo. A floresta amaz?nica faz parte desse cen?rio e sua alta diversidade ainda n?o foi totalmente identificada, assim como os padr?es que a regulam. Embora as pesquisas sobre a biodiversidade desse bioma tenham avan?ado nos ?ltimos anos, determinados grupos ainda apresentam conhecimento restrito sobre sua distribui??o geogr?fica e sazonal ou at? mesmo s?o ignorados em estudos de monitoramento, conserva??o e manejo. Nesse sentido, o objetivo principal desse estudo foi conhecer a composi??o, riqueza e raridade das esp?cies de formigas poneromorfas utilizando diferentes t?cnicas de amostragem, assim como investigar o efeito da sazonalidade e de determinados fatores ambientais na comunidade. As formigas foram coletadas na Floresta Nacional Tapirap?-Aquir? em julho de 2009, janeiro e julho de 2010, e janeiro de 2011 em tr?s ?reas distintas (A1, A2 e A3). Nas ?reas A1 e A2 foram determinados quatro pontos de amostragem no interior da mata onde foram feitos dois transectos de 100 metros e instalada a cada 10 metros uma armadilha tipo pitfall e iscas atrativas de sardinha sobre a vegeta??o subarbustiva e no solo. O pitfall permaneceu ativo por 48 horas e as iscas durante uma hora. Na ?rea A3 foi determinada apenas uma dist?ncia dentro da mata onde foram realizados os mesmos procedimentos de amostragem. Foram encontradas 46 esp?cies de formigas poneromorfas, pertencentes a oito g?neros. A t?cnica de amostragem que teve maior efic?cia em rela??o a riqueza da mirmecofauna encontrada foi o pitfall, que registrou 44 esp?cies (95,7% do total) e incluiu todos os g?neros encontrados. Em seguida, a isca no solo apresentou riqueza de 19 esp?cies (41,3% do total) e a isca sobre a vegeta??o apresentou riqueza de seis esp?cies (13% do total). Todas as formigas encontradas pertencem a duas sub-fam?lias, sendo elas Ponerinae e Ectatomminae. As esp?cies Gnamptogenys striatula Mayr, 1883 e Pachycondyla unidentata (Mayr, 1862) foram encontradas apenas nas iscas sobre a vegeta??o, estando ausentes nas iscas no solo e no pitfall em toda amostragem. Os resultados para composi??o da fauna de formigas poneromorfas e sua distribui??o sazonal indicam n?o haver uma clara estratifica??o na comunidade, sendo que as esp?cies de formigas que ocorreram na esta??o seca e na esta??o chuvosa n?o formam grupos distintos nas tr?s ?reas amostradas. Os testes estat?sticos aplicados para avaliar a influ?ncia das vari?veis ambientais medidas sobre a distribui??o das esp?cies de formigas poneromorfas n?o revelaram padr?es de associa??o. A identifica??o das esp?cies encontradas tem especial relev?ncia pelo fato de contribuir para a consolida??o do conhecimento da biodiversidade de formigas poneromorfas na Floresta Amaz?nica e permitir estudos comparativos com outras regi?es de floresta tropical.

Granular materials are abundant in the natural and industrial environment. Typical granular materials are collections of inert, passive particles in which the constituent grains of the material are macroscopic; thus they fill space, are athermal, and interact through only local contact forces. This definition can be broadened to include non-inert particles as well-active particles-in which the grains of an active granular material possess an internal energy source which drives motion. Active granular materials are found in many areas of the biological world, from cattle stampedes and pedestrian traffic flow, to the subterranean world of ant colonies and their collective motion within the nest. We study the rheology and dynamics of inert granular material, and an active granular system of collections of fire-ants, which together we call matter with granularity. In both of these systems we observe bifurcations in the force and flow dynamics which results from confinement effects of the effectively rigid granular materials. In inert granular systems, the onset of flow among particles that are closely packed together causes them to dilate as particles must separate away from each other to accommodate flow. Dilation is a property unique to matter with granularity and other complex fluids in which particles interact locally and occupy space. We explore how dilation influences the inert granular system in situations of local and global forcing: drag of an immersed intruder and avalanche flow respectively. We next study collections of fire ants which also interact with each other locally through contact forces and exclude volume. We study the construction of, and locomotion within subterranean tunnels by groups of fire ants. We find that the traffic dynamics of ants within confined tunnels are significantly affected by tunnel diameter. Reducing tunnel diameter increases the formation of traffic jams due to the inability of ants to pass each other easily. However, we show that jamming within tunnels may have beneficial effects on subterranean locomotion. Individual ants jam there bodies against the walls of vertical tunnels to resist falling. From physics studies of fire ant mobility in confined spaces, we show that subterranean tunnel size has a significant effect on the stability and mobility of ants within these environments.

Altruism in its extreme form is seen in social insects where most individuals give up their own reproduction and work to rear the offspring of their queen. The origin and evolution of such sterile worker castes remains a major unsolved problem in evolutionary biology. Primitively eusocial polistine wasps are an attractive model system for investigating this phenomenon. Ropalidia marginata (Lep.) (Hymenoptera: Vespidae) is one such tropical primitively eusocial wasp, in which new nests are initiated either by a single foundress or by a group of female wasps. Worker behaviour in Ropalidia marginata cannot be satisfactorily explained by the haplodiploidy hypothesis due to the existence of polyandry and serial polygyny which reduce intra-colony genetic relatedness to levels lower than the value expected between a solitary foundress and her offspring. Besides, wasps appear to move frequently between newly initiated nests, perhaps further reducing intracolony genetic relatedness. To study social organization and examine the possibility of kin recognition and task specialization under conditions of low intra-colony relatedness, genetically mixed colonies were created by introducing alien one-day old wasps onto recipient nests. As a first step I have tried to determine the factors that influence the acceptance of foreign wasps onto established colonies. I have introduced wasps between 1 to 20 days of age from donor colonies located at least 10 km away onto 12 different recipient colonies, observed these wasps for a period of 10 hours and later dissected them to examine their ovarian condition. Observations were carried out in the blind i.e. the observer was unaware of the identity of the wasps. Wasps upto 6 days of age were accepted by the alien nests. Older wasps may have been rejected because their relatively better ovarian condition may have been perceived as a reproductive threat to the recipient nest. Alternatively, younger wasps may have been accepted because they may be more easily moulded to the desired roles or due to some other correlate of age per se independent of ovarian condition. Although ovarian condition appeared to influence the probability of acceptance, it was not statistically significant in the presence of age in multiple regression models, making a favourable case for the 'ease of moulding hypothesis' or 'age per se hypothesis' over the 'reproductive threat hypothesis'. In any case these findings gave me a method to create genetically mixed colonies. On 12 different nests Ropalidia marginata, I similarly introduced one-day old wasps and thus created genetically mixed colonies. Such an introduction simulates the eclosion of distantly related individuals which is quite common on nests of R. marginata due to the presence of serial polygyny. About 7 such wasps were introduced per colony and the introductions were so arranged as to matched with natural eclosions on the recipient nest. After 7 days following the last introduction, colonies were observed for 20 hours each. Alien wasps became well integrated and performed most of the behaviours and tasks shown by the natal wasps. There was no evidence of kin recognition or task specialization between natal and introduced wasps. The introduced wasps also sometimes became replacement queens. In an attempt to test the costs in terms of brood rearing efficiency, of living in such genetically variable groups, I created kin and non-kin pairs of wasps in plastic containers. They were provided with ad libitum food, water and building material. The nests initiated were monitored till an adult offspring eclosed. There were no detectable differences in either the productivities or the developmental periods of immature stages in the kin and nonkin pairs suggesting that there is no apparent cost of living with unrelated or distantly related individuals. To compare the extent of cooperation between the two wasps in kin and non-kin pairs, I conducted behavioural observations on 12 pairs each of kin and nonkin wasps. I found no difference in the rates at which the non-egg layers brought food and pulp, fed larvae and built the nest in the kin and nonkin pairs suggesting that cooperative nest building and brood rearing was common to the kin as well as non-kin pairs. The results reported here strengthen the idea that factors other than genetic relatedness must play a prominent role in the maintenance of worker behaviour in Ropalidia marginata.

Between individual behavioral variation has been described in nearly every animal taxa where it has been measured. Often, these behavioral variations correlate across contexts, forming a behavioral syndrome. Despite a recent push to better understand the origins and consequences of behavioral syndromes, there still is no cohesive framework that describes this phenomenon. Here, I develop a social insect species into a model for measuring and testing behavioral syndromes at a new level of biological organization; the colony. This builds upon the rich literature describing between-colony variation in behavior and provides novel insights into the evolution of behavioral syndromes. In my first chapter I show that colonies do not vary from one another in foraging distance, nor is foraging distance directly associated with colony size. This was my first step in demonstrating that colony behavioral variation is not simply a byproduct of colony size. In chapter two, I expanded upon this finding by testing colonies both in the lab and in the field for a variety of ecologically relevant behaviors. Here, I found that there was a behavioral syndrome that reflected foraging distance, foraging effort to novel and familiar resources, response to threat and aggression. While there is a gradient of phenotypes, some colonies either travel farther to forage for food and respond more aggressively when confronted with a conspecific invader, but appear to invest less in each given incident or food source. I consider this to be more risk-tolerant; they increase their risk of external mortality for potentially larger pay-offs. On the other hand, risk-averse colonies deploy more foragers to exploit closer resources, increase their overall activity in the response to threat, but avoid travelling farther distances or aggressively engaging invaders. Additionally, there is between population variations in risk-taking phenotype. Across the western United States, colonies at more northern latitudes are more risk-tolerant than colonies at more southern latitudes. In chapter 3, I expand upon this latitudinal gradient in behavioral phenotype by investigating what ecological factors predict a colonies level of risk-tolerance. Specifically, I focused on ecological traits that reflected predation, competition, food resource availability and abiotic stress. I found that competition for nest sites and spatial clustering predicted behavioral type; colonies at high levels of nest site competition or spatial clustering were more risk-tolerant than colonies at lower levels of competition or were more spatially dispersed. In chapter 4, I used a common garden and brood transfer experiment to investigate if the relationship between the ecological environment and behavior was the result of phenotypic plasticity or local adaptation. I show that local adaptation is the most likely explanation, as colonies with more workers from the donor colony are more, behaviorally, like the donor colony than colonies with fewer donor workers. In chapter 5 I test if the risk-taking behavioral syndrome is the result of life history strategy variation. I test the growth rate and energy allocation towards either somatic effort or reproductive effort. I found that colonies which are risk-tolerant also grow faster and dedicate more energy towards reproductive effort, which is consistent with predictions built from life history theory. This body of work shows that behavioral syndromes can exist at a new level of organization, the colony, and that variation in behavioral type is the result of differential selection pressure between populations. This directly connects behavioral syndrome research to life history strategy research. As life history strategy theory is a well-understood field, this represents a true advancement in the field of behavioral syndromes.

Sistemas multiagente são construídos para atingir objetivos complexos e abrangentes, que estão além da capacidade de um único agente. Estes objetivos podem ser representados através de tarefas, que devem ser realizadas pelos agentes de forma a otimizar o desempenho do sistema. Em muitos ambientes reais, a escala do problema envolve tanto uma grande quantidade de agentes, quanto uma grande quantidade de tarefas. Além disto, os agentes devem lidar com informações incompletas, realizando tarefas em tempo hábil. O termo extreme teams foi introduzido na literatura para designar as seguintes quatro características da alocação de tarefas: oa ambientes são dinâmicos; os agentes podem realizar múltiplas tarefas; os agentes podem possuir funcionalidades sobrepostas; e podem existir interrelacionamentos entre tarefas, impondo, por exemplo, necessidade de realização simultânea. Abordagens existentes na literatura tratam, efetivamente, apenas as três primeiras características de extreme teams. Esta dissertação apresenta um algoritmo para alocação de tarefas, chamado eXtreme-Ants, que trata todas as quatro características de extreme teams. O algoritmo é inspirado no sucesso ecológico dos insetos sociais, e utiliza as metáforas de divisão de trabalho e recrutamento para transporte cooperativo. A metáfora de divisão de trabalho proporciona decisões rápidas e eficientes, atendendo as três primeiras características de extreme teams. O recrutamento permite formar grupos de agentes comprometidos com a realização simultânea de tarefas que exigem esforço conjunto, atendendo a quarta característica: inter-relacionamentos entre tarefas. Com isto, concretiza-se de fato o conceito completo de extreme teams. Experimentos foram realizados em dois ambientes distintos: um simulador independente de domínio e o simulador RoboCup Rescue. Os resultados obtidos demonstraram que a eficiência do eXtreme-Ants é balanceada com relação ao desempenho, quantidade de comunicação e esforço computacional. / Multiagent systems aim at achieving complex and broad goals, which are beyond the capability of a single agent. These goals can be represented by tasks, which must be performed by the agents in order to optimize the performance of the system. In many real-world environments, the scale of problems involves both a large number of agents and a large number of tasks. Besides, the agents must reason with incomplete and uncertain information, in a timely fashion. The expression extreme teams was introduced in the literature to describe the following four characteristics regarding task allocation: dynamic environments; agents may perform multiple tasks; agents can have overlapping functionality; and inter-task constraints (such as simultaneous execution requirements) may be present. Existing approaches effectively deal with just the three first characteristics of extreme teams. This dissertation presents an algorithm for allocating tasks to agents, called eXtreme- Ants, which deals with all the four characteristics of extreme teams. The algorithm is inspired in the ecological success of social insects, and uses the metaphors of division of labor and recruitment for cooperative transport. The metaphor provides fast and efficient decision-making, complying to the first three characteristics. The recruitment ensures the formation of groups of agents committed to the simultaneous execution of tasks that require joint efforts, complying to the fourth characteristic: inter-task constraints. Thus, the full concept of extreme teams is indeed realized. Experiments were performed in two distict environments: a domain independent simulator, and the RoboCup Rescue simulator. The results shown that eXtreme-Ants achieves a balanced efficiency regarding performance, communication, and computational effort.

In this thesis we study a mathematical model that describes task partitioning in a colony of ants. This process of self-organization is modeled by a nonlinear coupled system of rst order autonomous ordinary dierential equations. We discuss how this system of equations can be derived based on the behavior of ants in a colony. We use GNU Octave (a high-level programming language) to solve the system of equations numerically for dierent sets of parameters and show how the solutions respond to changes in the parameter values. Finally, we prove that the model is well-posed locally in time. We rewrite the system of ordinary dierential equations in terms of a system of coupled Volterra integral equations and look at the right-hand side of the system as a nonlinear operator on a Banach space. By doing so, we have transformed the problem of showing existence and uniqueness of solutions to a system of ordinary dierential equations into a problem of showing existence and uniqueness of a xed point to the corresponding integral operator. Additionally, we use Gronwall's inequality to prove the stability of solutions with respect to data and parameters.

Sistemas multiagente são construídos para atingir objetivos complexos e abrangentes, que estão além da capacidade de um único agente. Estes objetivos podem ser representados através de tarefas, que devem ser realizadas pelos agentes de forma a otimizar o desempenho do sistema. Em muitos ambientes reais, a escala do problema envolve tanto uma grande quantidade de agentes, quanto uma grande quantidade de tarefas. Além disto, os agentes devem lidar com informações incompletas, realizando tarefas em tempo hábil. O termo extreme teams foi introduzido na literatura para designar as seguintes quatro características da alocação de tarefas: oa ambientes são dinâmicos; os agentes podem realizar múltiplas tarefas; os agentes podem possuir funcionalidades sobrepostas; e podem existir interrelacionamentos entre tarefas, impondo, por exemplo, necessidade de realização simultânea. Abordagens existentes na literatura tratam, efetivamente, apenas as três primeiras características de extreme teams. Esta dissertação apresenta um algoritmo para alocação de tarefas, chamado eXtreme-Ants, que trata todas as quatro características de extreme teams. O algoritmo é inspirado no sucesso ecológico dos insetos sociais, e utiliza as metáforas de divisão de trabalho e recrutamento para transporte cooperativo. A metáfora de divisão de trabalho proporciona decisões rápidas e eficientes, atendendo as três primeiras características de extreme teams. O recrutamento permite formar grupos de agentes comprometidos com a realização simultânea de tarefas que exigem esforço conjunto, atendendo a quarta característica: inter-relacionamentos entre tarefas. Com isto, concretiza-se de fato o conceito completo de extreme teams. Experimentos foram realizados em dois ambientes distintos: um simulador independente de domínio e o simulador RoboCup Rescue. Os resultados obtidos demonstraram que a eficiência do eXtreme-Ants é balanceada com relação ao desempenho, quantidade de comunicação e esforço computacional. / Multiagent systems aim at achieving complex and broad goals, which are beyond the capability of a single agent. These goals can be represented by tasks, which must be performed by the agents in order to optimize the performance of the system. In many real-world environments, the scale of problems involves both a large number of agents and a large number of tasks. Besides, the agents must reason with incomplete and uncertain information, in a timely fashion. The expression extreme teams was introduced in the literature to describe the following four characteristics regarding task allocation: dynamic environments; agents may perform multiple tasks; agents can have overlapping functionality; and inter-task constraints (such as simultaneous execution requirements) may be present. Existing approaches effectively deal with just the three first characteristics of extreme teams. This dissertation presents an algorithm for allocating tasks to agents, called eXtreme- Ants, which deals with all the four characteristics of extreme teams. The algorithm is inspired in the ecological success of social insects, and uses the metaphors of division of labor and recruitment for cooperative transport. The metaphor provides fast and efficient decision-making, complying to the first three characteristics. The recruitment ensures the formation of groups of agents committed to the simultaneous execution of tasks that require joint efforts, complying to the fourth characteristic: inter-task constraints. Thus, the full concept of extreme teams is indeed realized. Experiments were performed in two distict environments: a domain independent simulator, and the RoboCup Rescue simulator. The results shown that eXtreme-Ants achieves a balanced efficiency regarding performance, communication, and computational effort.

abstract: The study of wasp societies (family Vespidae) has played a central role in advancing our knowledge of why social life evolves and how it functions. This dissertation asks: How have scientists generated and evaluated new concepts and theories about social life and its evolution by investigating wasp societies? It addresses this question both from a narrative/historical and from a reflective/epistemological perspective. The historical narratives reconstruct the investigative pathways of the Italian entomologist Leo Pardi (1915-1990) and the British evolutionary biologist William D. Hamilton (1936-2000). The works of these two scientists represent respectively the beginning of our current understanding of immediate and evolutionary causes of social life. Chapter 1 shows how Pardi, in the 1940s, generated a conceptual framework to explain how wasp colonies function in terms of social and reproductive dominance. Chapter 2 shows how Hamilton, in the 1960s, attempted to evaluate his own theory of inclusive fitness by investigating social wasps. The epistemological reflections revolve around the idea of investigative framework for theory evaluation. Chapter 3 draws on the analysis of important studies on social wasps from the 1960s and 1970s and provides an account of theory evaluation in the form of an investigative framework. The framework shows how inferences from empirical data (bottom-up) and inferences from the theory (top-down) inform one another in the generation of hypotheses, predictions and statements about phenomena of social evolution. It provides an alternative to existing philosophical accounts of scientific inquiry and theory evaluation, which keep a strong, hierarchical distinction between inferences from the theory and inferences from the data. The historical narratives in this dissertation show that important scientists have advanced our knowledge of complex biological phenomena by constantly interweaving empirical, conceptual, and theoretical work. The epistemological reflections argue that we need holistic frameworks that account for how multiple scientific practices synergistically contribute to advance our knowledge of complex phenomena. Both narratives and reflections aim to inspire and inform future work in social evolution capitalizing on lessons learnt from the past. / Dissertation/Thesis / Doctoral Dissertation Biology 2016

abstract: The most abundantly studied societies, with the exception of humans, are those of the eusocial insects, which include all ants. Eusocial insect societies are typically composed of many dozens to millions of individuals, referred to as nestmates, which require some form of communication to maintain colony cohesion and coordinate the activities within them. Nestmate recognition is the process of distinguishing between nestmates and non-nestmates, and embodies the first line of defense for social insect colonies. In ants, nestmate recognition is widely thought to occur through olfactory cues found on the exterior surfaces of individuals. These cues, called cuticular hydrocarbons (CHCs), comprise the overwhelming majority of ant nestmate profiles and help maintain colony identity. In this dissertation, I investigate how nestmate recognition is influenced by evolutionary, ontogenetic, and environmental factors. First, I contributed to the sequencing and description of three ant genomes including the red harvester ant, Pogonomyrmex barbatus, presented in detail here. Next, I studied how variation in nestmate cues may be shaped through evolution by comparatively studying a family of genes involved in fatty acid and hydrocarbon biosynthesis, i.e., the acyl-CoA desaturases, across seven ant species in comparison with other social and solitary insects. Then, I tested how genetic, developmental, and social factors influence CHC profile variation in P. barbatus, through a three-part study. (1) I conducted a descriptive, correlative study of desaturase gene expression and CHC variation in P. barbatus workers and queens; (2) I explored how larger-scale genetic variation in the P. barbatus species complex influences CHC variation across two genetically isolated lineages (J1/J2 genetic caste determining lineages); and (3) I experimentally examined how CHC development is influenced by an individual’s social environment. In the final part of my work, I resolved discrepancies between previous findings of nestmate recognition behavior in P. barbatus by studying how factors of territorial experience, i.e., spatiotemporal relationships, affect aggressive behaviors among red harvester ant colonies. Through this research, I was able to identify promising methodological approaches and candidate genes, which both broadens our understanding of P. barbatus nestmate recognition systems and supports future functional genetic studies of CHCs in ants. / Dissertation/Thesis / Doctoral Dissertation Biology 2016

abstract: For interspecific mutualisms, the behavior of one partner can influence the fitness of the other, especially in the case of symbiotic mutualisms where partners live in close physical association for much of their lives. Behavioral effects on fitness may be particularly important if either species in these long-term relationships displays personality. Animal personality is defined as repeatable individual differences in behavior, and how correlations among these consistent traits are structured is termed behavioral syndromes. Animal personality has been broadly documented across the animal kingdom but is poorly understood in the context of mutualisms. My dissertation focuses on the structure, causes, and consequences of collective personality in Azteca constructor colonies that live in Cecropia trees, one of the most successful and prominent mutualisms of the neotropics. These pioneer plants provide hollow internodes for nesting and nutrient-rich food bodies; in return, the ants provide protection from herbivores and encroaching vines. I first explored the structure of the behavioral syndrome by testing the consistency and correlation of colony-level behavioral traits under natural conditions in the field. Traits were both consistent within colonies and correlated among colonies revealing a behavioral syndrome along a docile-aggressive axis. Host plants of more active, aggressive colonies had less leaf damage, suggesting a link between a colony personality and host plant health. I then studied how aspects of colony sociometry are intertwined with their host plants by assessing the relationship among plant growth, colony growth, colony structure, ant morphology, and colony personality. Colony personality was independent of host plant measures like tree size, age, volume. Finally, I tested how colony personality influenced by soil nutrients by assessing personality in the field and transferring colonies to plants the greenhouse under different soil nutrient treatments. Personality was correlated with soil nutrients in the field but was not influenced by soil nutrient treatment in the greenhouse. This suggests that soil nutrients interact with other factors in the environment to structure personality. This dissertation demonstrates that colony personality is an ecologically relevant phenomenon and an important consideration for mutualism dynamics. / Dissertation/Thesis / Doctoral Dissertation Biology 2018