Behavioral flexibility, the ability to change behavior in accordance with the changing environment, was studied in pigeons using a series of reversal learning paradigms. All experiments involved a series of 5-trial sequences and I was interested in whether pigeons are sensitive to the reversal by switching to the other alternative after a single error. In Experiments 1 and 2, the overall probability of the two stimuli was equated over sequences, but the probability correct of the two stimuli changed across trials. In both experiments, subjects showed no sensitivity to the differences in sequence type. Instead they used the overall average of the probability of reinforcement on each trial as the basis of choice. In the final two experiments, the likelihood that a reversal would occur on a given trial was equated such that there was an equal overall probability that the two stimuli would be correct on a given trial, but the overall probability of each stimulus being correct across sequences favored the second correct stimulus (S2). In Experiment 3, the overall probability of S2 correct was 80%, and results showed that subjects consistently chose S2 regardless of sequence type or trial number. In Experiment 4, the overall likelihood of S2 correct was 65%, and results showed that subjects began all sequences at chance, and as the sequence progressed, began choosing S2 more often. In all experiments, subjects showed remarkably similar behavior regardless of where (or whether) the reversal occurred in a given sequence. Therefore, subjects appeared to be insensitive to the consequences of responses within a sequence (local information) and instead, seemed to be averaging over the sequences based on the overall probability of reinforcement for S1 or S2 being correct on each trial (aggregate information), thus not maximizing overall reinforcement. Together, the results of this series of experiments suggest that pigeons have a basic disposition for using the overall probability instead of using local feedback cues provided by the outcome of individual trials. The fact that pigeons do not use the more optimal information afforded by recent reinforcement contingencies to maximize reinforcement has implications for their use of flexible response strategies under reversal learning conditions.

No description available.

The relationship between alcohol consumption and traumatic brain injury (TBI) often focuses on alcohol consumption increasing the likelihood of incurring a TBI, rather than alcohol use outcomes after TBI. This focus is in part due to the large numbers of TBI patients visiting emergency rooms notable levels of alcohol in their blood. Additionally, increases in alcohol use disorders following TBI can be predicted by previous history of alcohol use. However, studies have also shown patients without a history of an alcohol use disorder can experience increases in problem drinking after single or multiple TBIs. Due to the diffuse impact of alcohol consumption and mild TBI on the brain, it is likely that an interaction exists between TBI outcomes and problematic alcohol use after TBI. To examine the impact of mild repetitive TBI (rmTBI) on voluntary alcohol consumption, male mice were subjected to four mild TBI or sham procedures over a two week period, then offered ethanol (20% v/v) for 2, 4, 6 or 8 weeks using the two-bottle choice, drinking in the dark paradigm. Following the drinking period, mice were sacrificed and brains were extracted to examine expression of the pro-inflammatory cytokine TNF-α, a possible shared mechanism of neuronal damage. An additional cohort of mice was subjected to the same rmTBI and voluntary ethanol paradigm and tested for cognitive and behavioral deficits following the set drinking period. Results indicate there is a temporary decrease in ethanol consumption following rmTBIs compared to Sham mice in this model. Results also suggest an attenuated expression of TNF-α in rmTBI, ethanol drinking groups compared to ethanol exposed mice after the Sham procedure. The outcomes of the cognitive and behavioral tasks suggest that ethanol consumption after rmTBI can cause transient cognitive dysfunction and increased novelty preference.

Foraging theory suggests that hungry animals balance a complex set of costs and benefits when determining what and how to eat. Prey distribution, patch size, and the presence of conspecifics are important factors influencing a predator's feeding tactics, including the decision to feed individually or socially. Dusky dolphins (Lagenorhynchus obscurus) in New Zealand employ different feeding tactics in varying habitats and seasons. I used programmed survey routes and opportunistic sightings to examine the habitat use and feeding mechanics of dusky dolphins in Admiralty Bay, New Zealand, a protected shallow-water environment frequented by wintering dolphins. I encountered 253 dolphin groups, of which 58.5% were engaged in food-acquisition activities. Photographic efforts revealed a total of 177 individually-recognizable dolphins, 100 of which were returnees from previous seasons. Thirty-seven feeding groups and 70 bouts of feeding behavior were followed. Two-minute interval sampling as well as active acoustic sonar were used to test the hypothesis that diurnally-feeding dolphins would work in a coordinated manner to bring schooling fish to the surface. Feeding tactics observed in Admiralty Bay were then compared to foraging by some of the same animals in the unprotected, deep-water environment off Kaikoura, where large numbers of dusky dolphins feed during the night on organisms associated with a vertically-migrating scattering layer. Evidence supporting coordinated surface feeding was not statistically significant, but indicative of behavioral flexibility in feeding styles as part of a larger feeding repertoire. A potential shift in prey distribution from previous years may also explain some observed patterns. Feeding groups were positively correlated with seabirds and New Zealand fur seals (Arctocephalus forsteri). Mean group size of 6.1 (± 8.23 S.D., n=253) in Admiralty Bay is dramatically less than groups observed off Kaikoura, a variation likely reflecting differences in prey number and distribution, as well as differences in predation risk by deep-water sharks and killer whales. Behavioral flexibility likely confers an adaptive advantage for species subject to environmental fluctuation, whether due to natural or anthropogenic sources. Further research is necessary to evaluate prey distribution in Admiralty Bay and its possible effects on feeding dusky dolphins.

<p>Changing environmental conditions may present substantial challenges to organisms experiencing them. In animals, the fastest way to respond to these changes is often by altering behavior. This ability, called behavioral flexibility, varies among species and can be studied on several levels. First, the extent of behavioral flexibility exhibited by a species can be determined by observation of that species' behavior, either in nature or in experimental settings. Second, because the central nervous system is the substrate determining behavior, neuroanatomy can be studied as the proximate cause of behavioral flexibility. Finally, the ultimate causation can be examined by studying ecological factors that favor the evolution of behavioral flexibility. In this dissertation, I investigate behavioral flexibility across all three levels by examining the relationship between habitat structure, the size of different structures within the brain and total brain size, and behavioral flexibility in six closely-related species of Puerto Rican <italic>Anolis</italic> lizards. <italic>Anolis</italic> lizards provide an excellent taxon for this study as certain species, including those used here, are classified as belonging to different ecomorphs and are morphologically and behaviorally specialized to distinct structural habitat types.</p><p>In order to determine the presence of behavioral flexibility in <italic>Anolis</italic>, I first presented <italic>Anolis evermanni</italic> with a series of tasks requiring motor learning and a single instance of reversal learning. <italic>Anolis evermanni</italic> demonstrated high levels of behavioral flexibility in both tasks.</p><p>To address the pattern of brain evolution in the <italic>Anolis</italic> brain, I used a histological approach to measure the volume of the whole brain, telencephalon, dorsal cortex, dorsomedial cortex, medial cortex, dorsal ventricular ridge, cerebellum, and medulla in six closely-related species of Puerto Rican <italic>Anolis</italic> lizards belonging to three ecomorphs. These data were analyzed to determine the relative contribution of concerted and mosaic brain evolution to <italic>Anolis</italic> brain evolution. The cerebellum showed a trend toward mosaic evolution while the remaining brain structures matched the predictions of concerted brain evolution. </p><p>I then examined the relationship between the complexity of structural habitat occupied by each species and brain size in order to determine if complex habitats are associated with relatively large brains. I measured brain volume using histological methods and directly measured habitat complexity in all six species. Using Principal Component Analysis, I condensed the measures of habitat structure to a single variable and corrected it for the scale of each lizard species' movement, calling the resulting measurement relevant habitat complexity. I tested the relationship between relative volume of the telencephalon, dorsal cortex, dorsomedial cortex, and whole brain against both relative habitat complexity and ecomorph classification. There was no relationship between the relative volume of any brain structure examined and either relevant habitat complexity or ecomorph. However, relevant habitat complexities for each species did not completely match their ecomorph classifications. </p><p>Finally, I tested the levels of behavioral flexibility of three species of <italic>Anolis</italic>, <italic>A. evermanni</italic>, <italic>A. pulchellus</italic>, and <italic>A. cristatellus</italic>, belonging to three distinct ecomorphs, by presenting them with tasks requiring motor and reversal learning. <italic>Anolis evermanni</italic> performed well in both tasks, while <italic>A. pulchellus</italic> required more trials to learn the motor task. Only a single <italic>Anolis cristatellus</italic> was able to perform either task. <italic>Anolis evermanni</italic> displayed lower levels of neophobia than the other species, which may be related to its superior performance.</p><p>In combination, this research suggests that <italic>Anolis</italic> of different ecomorphs display different levels of behavioral flexibility. At the proximate level, this difference in behavioral flexibility cannot be explained by changes in the relative size of the total brain or brain structures associated with cognitive abilities in other taxa. At the ultimate level, the size of the brain and several constituent structures cannot be predicted by habitat complexity. However, behavioral flexibility in certain tasks may be favored by utilization of complex habitats. Flexibility in different tasks is not correlated, rendering broad comparisons to a habitat complexity problematic.</p> / Dissertation

Indiana University-Purdue University Indianapolis (IUPUI) / Although marijuana and alcohol are two of the most commonly used drugs in the United States, relatively little is understood about how these drugs interact to effect drug use, cognitive behaviors, and neurophysiological changes. Specific drug use patterns such as simultaneous use may produce differential effects for consumption and other behaviors in addition to unique neurobiological changes compared to singular drug use. In order to better understand the effects of simultaneous alcohol and marijuana (SAM) use, we used the selectively bred crossed High Alcohol Preferring mice to examine consummatory, cognitive, and neurobiological changes following chronic alcohol and THC self-administration. We hypothesized that SAM mice would consume more drug than animals exposed to either substance alone. We used an operant behavioral flexibility paradigm to assess cognitive impairments believing that drug-exposed animals would show deficits relative to Control animals, with SAM mice being the most impaired of all drug conditions. Finally, we assessed CB1 receptor changes in the dorsal striatum, as this region is critical for behavioral flexibility (Bissonette & Powell, 2012; Ragozzino, 2007), CB1 receptors are the primary target of THC and these receptors are involved in numerous alcohol related behaviors (Maldonado et al., 2006; Pava & Woodward, 2012). Contrary to our hypothesis, SAM animals did not consume higher levels of drug compared to mice exposed to only THC or alcohol. Interestingly, female THC consumption was robust when THC was consumed alone but was reduced when simultaneous access to alcohol was available. Surprisingly, although we speculated that drug-exposed mice would be impaired compared to Control animals, and that SAM animals would likely be more compromised than THC and alcohol for Reversal Learning and Attentional Set-Shifting respectively, behavioral flexibility deficits were absent in our paradigm. Finally, alterations to dorsal striatal CB1 receptor expression were observed following a Short Abstinence period. Despite an absence of cognitive behavioral effects, this research contributes to furthering our understanding of co-drug use for consummatory and neurobiological changes, both of which are critically necessary given the evolving landscape surrounding simultaneous alcohol and recreational marijuana use.

Understanding spatial and temporal diversity and distribution patterns of species along with the drivers of these patterns has long been a theme of community ecology. Primates, a very species-rich taxonomic group, able to occupy various habitat types, are known for their broad behavioral repertoire and flexibility. This, in turn, allows them to adapt quickly to different ecological conditions. Therefore, they represent an ideal group for examining aspects of community ecology such as species diversity and co-occurrence, distribution patterns, and the ecological determinants of such factors. This dissertation investigates the ways in which members of a multispecies primate community inhabiting a mosaic landscape comprised of flooded and non-flooded forests in northeastern Peru (western Amazonia) distributes themselves across time and space. The main objectives of this study are threefold: 1) to categorize, confirm, and differentiate previously identified habitat types across a mosaic landscape; 2) to examine the diversity and distribution patterns (spatial and temporal) of a large multispecies primate community, and 3) to combine the habitat data with the primate data in order to determine which habitats are occupied by which species and to suggest ways in which the primates share and utilize the landscape throughout an annual cycle. However, special attention is paid to one particular species, the red uakari (Cacajao calvus ucayalii), because of its unusually large home and day ranges and its fluid social system known to change in size and composition daily and even hourly. One of the least studied primates to date, red uakaris, are investigated in order to determine whether or not their behavior varies across habitat types, seasons, and when other primates are present as they navigate a mosaic landscape. By identifying the ways in which uakaris modify their behaviors as they traverse multiple habitats throughout the year, determining both habitat-typical behaviors and seasonal behaviors exhibited by uakaris becomes possible. Moreover, shedding light on the community structure and habitat requirements of one of the least known primates has conservation implications. Research was conducted at the Tahuayo River Amazon Research Center (TRARC), located in northeastern Peru. Systematic data collection on primates and the environment occurred between September 2012 and February 2014, except April 2013. Sampling methods for primates consisted of two parts—a combination of line transect and reconnaissance (recce) surveys in order to determine encounter rates for each species across habitat types and 10-minute interval scan sampling during uakari follows in order to determine the effect that environmental and social factors have on their behavior as they traverse multiple habitats. Environmental sampling occurred in thirty plots established throughout the various habitat types. All trees within the test plots with a diameter breast height (DBH) > 10 cm were marked and the following parameters were recorded: DBH, height, and taxonomic classification. Additionally, plots were monitored monthly to record flooding data in order to determine variation in flooding patterns across habitat types. Plots allowed for the determination of which floristic variables and flood patterns are suitable to differentiate the habitat types described at the TRARC. Results indicate flood duration, average tree height, and (Importance Value Indices [IVIs] at the family, genus, and species levels) are suitable measures for defining and differentiating the five previously identified habitat types at the TRARC. Analysis of the entire primate community showed that the occurrence of species and patterns of distribution across a mosaic landscape vary throughout the year. Distribution patterns are more dependent on forest structure (habitat type) than on rainfall seasonality. While a few primates showed preferences for particular habitats (e.g., Lagothrix) or for certain seasons (e.g. Saimiri), the majority of primates demonstrated more generalized modes of ranging and foraging, with relatively equal encounter rates in all habitats across both wet and dry seasons. Results of the uakari data revealed that habitat and season had an effect on their behavior. There were meaningful differences in the behavioral categories of vocalizing, resting, moving, feeding, infant clinging, and being in polyspecific associations (PSAs) between flooded and non-flooded habitat types. Seasonal differences were seen for vocalizing, traveling, resting, and time spent in PSAs. Although results revealed that red uakaris spent the majority of the time alone (71.86%), when they were in PSAs with one other primate species, squirrel monkeys (Saimiri sciureus) were the most common monkeys. When uakaris were in PSAs with two other species, squirrel monkeys were always present, but woolly monkeys (Lagothrix lagotricha poeppigii) were the second most frequent species. In general, uakaris demonstrated behavioral differences across habitats and seasons. However, some behavioral consistencies across seasons were evident (e.g., moving, feeding, infant clinging), suggesting ecological flexibility in the species. Results of this dissertation provide a basis for understanding ecological parameters best suited for characterizing and differentiating habitat types in upper Amazonia and describe the diversity and distribution patterns of a multispecies community of primates occurring across a mosaic landscape, reinforcing the view that New World primates are largely ecological generalists within forest environments. Understanding the spatio-temporal relationships between species and their environments can aid in predictions of species occurrence/abundance and contribute to better management strategies and conservation prioritization.

Flexibilidade comportamental é a capacidade de ajustes comportamentais que permitem aos indivíduos responderem a um novo desafio ambiental podendo ser, ou pela modificação de suas respostas, ou por desenvolver novas estratégias diante de um novo estímulo. Esse novo comportamento pode ser alvo da seleção natural, apesar de não ser hereditário. O que é transferida para as próximas gerações, é a capacidade de ajustar o comportamento. Assim, é plausível assumir a existência de uma associação entre capacidades cognitivas e o desafio do ambiente. Neste contexto, espera-se que indivíduos territoriais exibam capacidades cognitivas associadas ao seu habitat específico. Estudos têm frequentemente focado em diferenças nas capacidades de resolução de problemas em animais de espécies e populações distintas. No entanto, o presente estudo compara capacidades de resolução de problemas de lagartos Tropidurus torquatus de uma mesma população que utilizam dois tipos de territórios, os quais diferem no grau de desafio: muros, ambientes desafiadores, e árvores, ambientes permissíveis. Essa espécie exibe um comportamento territorial em que machos dominantes e fêmeas associadas possuem uma fidelidade evidente aos seus territórios. Lagartos foram observados no campo para a caracterização do território e, posteriormente, realizaram testes de resolução de problemas no laboratório. Os resultados demonstraram que lagartos de ambientes desafiadores obtiveram um desempenho superior aos de ambientes permissíveis nos testes de resolução de problemas, e foram mais propensos em exibir uma inovação comportamental durante a resolução dos testes. As interpretações para esses resultados consistem em duas possíveis explicações. Lagartos de muros podem se beneficiar de capacidades cognitivas avançadas, pois a seleção natural teria agido na flexibilidade comportamental e selecionaria indivíduos que poderiam lidar com problemas de uma ambiente desafiador. Alternativamente, é possível que a maioria dos lagartos Tropidurus torquatus apresentem melhores capacidades de resolução de problema, porém esta característica estaria críptica, e apenas a interação entre o indivíduo e a vivência em ambientes desafiadores (muros) induziria o surgimento de melhores capacidades cognitivas. Os resultados desse estudo provavelmente indicam que diferenças nas capacidades de resolução de problemas e habilidades cognitivas entre indivíduos poderiam estar sob efeitos de regimes seletivos antes mesmo de ocorrer alguma segregação populacional. / Behavioral flexibility is the ability of behavioral adjustments that allow individuals to respond to a new environmental challenge by either modifying their responses or developing new strategies when facing novel stimuli. This new behavior may be target of natural selection, despite not being heritable. What is transferred to the next generation is the capacity to adjust behavior. Thus, it is plausible to assume the existence of an association between cognitive capabilities and environmental severity. In this context, it is expected that territorial individuals exhibit cognitive capabilities associated with their specific habitat. Studies have often been focused on differences of problem-solving capabilities in animals from different species and populations. Nevertheless, the present study compares problem-solving abilities of Tropidurus torquatus lizards from the same population that use two types of territories that differ in the level of harshness: house walls, a harsh environment, and trees, a mild environment. This species exhibits a territorial system where dominant males and associated females have an evident fidelity to their territories. Lizards were observed in the field for territory characterization and then performed problem-solving tests in the laboratory. The results show that lizards from harsh environments outperformed those from mild environments in the problem-solving tasks and were more likely to show a behavioral innovation when solving the task. Interpretations for these results resides on two possible explanations. Lizards from walls might benefit from enhanced cognitive capabilities because natural selection acted on behavioral flexibility and selected individuals that can deal with problems of a harsh environment. Alternatively, it is possible that the majority of Tropidurus torquatus lizards exhibit enhanced problem-solving capability, but this characteristic might be cryptic, and only the interaction between the individual and living in a harsh environment (walls) induces the emergence of enhanced cognitive capabilities. These findings probably indicate that differences in problem-solving and cognitive capabilities might be exposed to specific selective regimes even before population segregation occurs.

Made available in DSpace on 2014-07-29T16:21:18Z (GMT). No. of bitstreams: 1 Dissertacao_Priscylla_Amora.pdf: 2731370 bytes, checksum: df0bdce118cb2e0972accdf0962fb604 (MD5) Previous issue date: 2011-03-30 / Capuchin monkeys are holders of a strong cognition power and high behavioral flexibility. These features contribute to the adaptation to the various locations and situations. The aims of this study were to test whether capuchin monkeys modulate their behavioral response according to the presence of predators/competitors, the characteristics of the micro-environment and the physical and behavioral characteristics of humans involved interactions. The study was conducted in two natural environments located in Goiânia, Goiás: Parque Areião and Campus Samambaia UFG. Two populations of capuchin monkeys Cebus libidinosus were monitored from March to August 2010. The points of sampling were randomized from georeferenced image of the study sites was divided into quadrants of 50 m x 50 m. Data of hypothesis testing: The animal's tolerance for the approximation of the experimenter, were collected four times a week (6 hours / day). In this test we simulate a predation event using as a model of human predator. The approaching experimental sessions began after the obedience of prerequisites. In each session, we sampled the characteristics of the subject (sex and age) and location (canopy cover and understory, number of people and human objects), the initial, warning and escape distances of the animal with respect to the experimenter, the initial and final height of the animal and the distance traveled after the escape. In the hypothesis testing: Interaction between humans and capuchin monkeys, we observe all interactions between capuchin monkeys and visitors of the areas were the result of interactions were recorded, along with age, height, weight, shoulder width, length of hair and presence of bags to visitors, sex and age of the monkeys and characteristics of the micro-environment where the interactions occurred. The tolerance test showed that the physical characteristics of the monkeys and their position on the environment were closely related to the animal's behavioral response, suggesting that animals closer to the trees were able to better assess the risk of predation due to vegetation near it and thus escape the shorter distances. The interaction test indicated that the behavior emitted by the monkeys is affected by body type and behavior of visitors. Our results suggest that capuchin monkeys have the ability to predict the outcome of interactions between competitors and predators on the basis of physical characteristics and micro-environment, selecting those behaviors in their repertoire that enhance success. / Macacos-prego são detentores de um forte poder cognitivo, o que resulta em uma alta flexibilidade comportamental. Essa característica contribui para sua adaptação aos mais diversos locais e situações. Neste estudo, procuramos testar se o repertório comportamental dos macacos-prego é modulado em função da presença de predadores/competidores, das características do micro-ambiente e das características físicas e comportamentais dos humanos envolvidos nas interações. O estudo foi realizado em dois ambientes antropizados localizados em Goiânia, Goiás: o Parque Areião e o Campus Samambaia da UFG. Duas populações de macacos-prego Cebus libidinosus foram acompanhadas de março a agosto de 2010. Os pontos das observações foram aleatorizados a partir de imagem georeferenciada dos locais de estudo que foi dividida em quadrantes de 50 m x 50 m. Dados do teste de hipótese: Tolerância do animal em relação à aproximação do experimentador foram coletados quatro vezes por semana (6 horas/dia). Neste teste, simulamos um evento de predação utilizando um humano como modelo de predador. As sessões experimentais de aproximação começaram após a obediência de pré-requisitos Em cada sessão, foram amostradas as características do sujeito (sexo e idade) e do local (cobertura de dossel e sub-bosque, número de pessoas e objetos humanos), as distâncias inicial, de alerta e de fuga do animal com relação ao predador, a altura inicial e final do animal e a distância percorrida após a fuga. No teste de hipótese: Interação entre humanos e macacos-prego, observamos todas as interações entre macacos-prego e visitantes das áreas de estudo e o resultado das interações foi registrado, juntamente com a idade, altura, peso, largura do ombro, comprimento dos cabelos e presença de bolsas para os visitantes, o sexo e a idade dos macacos e características do micro-ambiente onde as interações ocorreram. O teste de tolerância demonstrou que o comportamento emitido pelos macacos é influenciado pelas características físicas dos macacos e sua posição no ambiente, o que sugere que indivíduos próximos às árvores fogem a menores distâncias, aumentando o tempo de avaliação de risco. Já o teste de interação indicou que o comportamento emitido pelos macacos é afetado pelo tipo físico e comportamento dos visitantes. Nossos resultados sugerem que os macacos-prego apresentam a capacidade de prever o resultado das interações entre competidores e predadores com base nas características físicas e micro-ambientais, selecionando os comportamentos em seu repertório que incrementam o sucesso.

Flexibilidade comportamental é a capacidade de ajustes comportamentais que permitem aos indivíduos responderem a um novo desafio ambiental podendo ser, ou pela modificação de suas respostas, ou por desenvolver novas estratégias diante de um novo estímulo. Esse novo comportamento pode ser alvo da seleção natural, apesar de não ser hereditário. O que é transferida para as próximas gerações, é a capacidade de ajustar o comportamento. Assim, é plausível assumir a existência de uma associação entre capacidades cognitivas e o desafio do ambiente. Neste contexto, espera-se que indivíduos territoriais exibam capacidades cognitivas associadas ao seu habitat específico. Estudos têm frequentemente focado em diferenças nas capacidades de resolução de problemas em animais de espécies e populações distintas. No entanto, o presente estudo compara capacidades de resolução de problemas de lagartos Tropidurus torquatus de uma mesma população que utilizam dois tipos de territórios, os quais diferem no grau de desafio: muros, ambientes desafiadores, e árvores, ambientes permissíveis. Essa espécie exibe um comportamento territorial em que machos dominantes e fêmeas associadas possuem uma fidelidade evidente aos seus territórios. Lagartos foram observados no campo para a caracterização do território e, posteriormente, realizaram testes de resolução de problemas no laboratório. Os resultados demonstraram que lagartos de ambientes desafiadores obtiveram um desempenho superior aos de ambientes permissíveis nos testes de resolução de problemas, e foram mais propensos em exibir uma inovação comportamental durante a resolução dos testes. As interpretações para esses resultados consistem em duas possíveis explicações. Lagartos de muros podem se beneficiar de capacidades cognitivas avançadas, pois a seleção natural teria agido na flexibilidade comportamental e selecionaria indivíduos que poderiam lidar com problemas de uma ambiente desafiador. Alternativamente, é possível que a maioria dos lagartos Tropidurus torquatus apresentem melhores capacidades de resolução de problema, porém esta característica estaria críptica, e apenas a interação entre o indivíduo e a vivência em ambientes desafiadores (muros) induziria o surgimento de melhores capacidades cognitivas. Os resultados desse estudo provavelmente indicam que diferenças nas capacidades de resolução de problemas e habilidades cognitivas entre indivíduos poderiam estar sob efeitos de regimes seletivos antes mesmo de ocorrer alguma segregação populacional. / Behavioral flexibility is the ability of behavioral adjustments that allow individuals to respond to a new environmental challenge by either modifying their responses or developing new strategies when facing novel stimuli. This new behavior may be target of natural selection, despite not being heritable. What is transferred to the next generation is the capacity to adjust behavior. Thus, it is plausible to assume the existence of an association between cognitive capabilities and environmental severity. In this context, it is expected that territorial individuals exhibit cognitive capabilities associated with their specific habitat. Studies have often been focused on differences of problem-solving capabilities in animals from different species and populations. Nevertheless, the present study compares problem-solving abilities of Tropidurus torquatus lizards from the same population that use two types of territories that differ in the level of harshness: house walls, a harsh environment, and trees, a mild environment. This species exhibits a territorial system where dominant males and associated females have an evident fidelity to their territories. Lizards were observed in the field for territory characterization and then performed problem-solving tests in the laboratory. The results show that lizards from harsh environments outperformed those from mild environments in the problem-solving tasks and were more likely to show a behavioral innovation when solving the task. Interpretations for these results resides on two possible explanations. Lizards from walls might benefit from enhanced cognitive capabilities because natural selection acted on behavioral flexibility and selected individuals that can deal with problems of a harsh environment. Alternatively, it is possible that the majority of Tropidurus torquatus lizards exhibit enhanced problem-solving capability, but this characteristic might be cryptic, and only the interaction between the individual and living in a harsh environment (walls) induces the emergence of enhanced cognitive capabilities. These findings probably indicate that differences in problem-solving and cognitive capabilities might be exposed to specific selective regimes even before population segregation occurs.