O gênero Cebus é um táxon que agrupa espécies arborícolas, cujo principal modo locomotor é o deslocamento quadrúpede e o principal modo postural é sentado. No entanto, todos os estudos publicados descrevem comportamentos posicionais de populações de floresta tropical, habitat ao qual o gênero não está restrito. Os objetivos do presente estudo foram (1) descrever o comportamento de uma população de Cebus libidinosus que habita uma área de ecótono Cerrado-Caatinga e (2) investigar se indivíduos de diferentes classes de gênero e de idade diferem em comportamento posicional, já que mudanças que acompanham os indivíduos em crescimento influenciam suas atividades cotidianas. Para coletar os dados comportamentais utilizei o método de varredura focal e para as análises estatísticas utilizei a regressão de Poisson. Os comportamentos posicionais, o uso de substrato e o uso de substrato arbóreo específico foram pesquisados por atividade, já que cada uma exige posicionamentos diferentes. As faixas etárias divergiram significativamente na freqüência de ocorrência das atividades alimentação, brincadeira e descanso e na freqüência de utilização de comportamentos posicionais como escalada, deslocamento quadrúpede, suspensão, entre outros, sugerindo que o desenvolvimento durante a ontogenia exige que os animais moldem os seus modos locomotores e posturais em função de características ambientais e das diferenças anatômicas e fisiológicas. Quanto aos substratos utilizados, os arbóreos foram sempre os preferidos (com exceção da atividade quebra, exclusivamente executada no chão) e os galhos múltiplos foram mais utilizados na maioria das atividades. Infantes utilizaram galhos múltiplos mais e galhos grandes menos do que adultos durante a atividade deslocamento. Indivíduos mais velhos utilizaram ambientes terrestres mais freqüentemente do que os mais novos nas atividades brincadeira e deslocamento. Nas atividades em que a literatura disponível permitiu comparações, Cebus libidinosus deste estudo utiliza substratos terrestres mais do que outras espécies do gênero, apesar de usar comportamentos posicionais e apresentar orçamentos de atividades similares a outras populações / The genus Cebus is a taxon that groups arboreal species in which the main locomotor mode is quadrupedal locomotion and the main posture mode is sitting down. However, all the studies reviewed describe positional behavior of rainforest inhabitating populations, an environment to which the genus is not restricted. The aims of this study were (1) to describe the behavior of a population of Cebus libidinosus that uses exclusively an ecotone Cerrado-Caatinga and (2) to check if individuals of different gender and age classes differ in their positional behaviors, since changes that accompany growing individuals influence their daily activities. I used the focal scan method to collect behavioral data and Poisson regression for the statistical analysis. The positional behavior, substrate use and the use of arboreal substrates were investigated by activity, since these require different placements. The age groups differed significantly in the frequency of feeding, play and rest activities. In most activities the age groups differed significantly in the frequency of use of positional behaviors such as climbing, quadrupedal locomotion, suspension, among others, suggesting their ontogenetic development requires animals to model their locomotor and postural modes depending on environmental characteristics and anatomical and physiological differences. As for the substrates used, the trees were always the favorites (except for the nutcrack activity, conducted exclusively on the ground) and multiple branches were more frequently used in most of the activities. Infants used multiple branches more and large single branches less than adults during travel. Older individuals used terrestrial environments more often than younger ones during play and travel. In the activities that the available literature allowed comparisons, the Cebus libidinosus of this study use terrestrial substrates more than other species of the genus, although they present similar positional behavior and activity budget

This thesis proposes a possibility of using the exposition of primates in the Prague zoo during the school excursion for pupils of the 7th or 8th grade of elementary school. The thesis is divided into individual parts that theoretically analyse the importance of excursions for education and subsequently it is practically focused on facilitating the smooth course of the excursion and other activities that precede the excursion or follow it freely. In the thesis there is the general sorting of primates into individual species described in detail and there is provided basic information about primates that are bred in the Prague zoo. Further, possible excursion trail including individual expositions where the particular animals can be seen is described in detail. The main objective was to provide teachers with detailed instructions on how to make the excursion so it is successful. The purpose of the work was also to create materials which help to actively memorize the information provided and to raise children's interest in such an interesting animal species as the primates. With regard to the fact that most primates are currently threatened by extinction in their natural habitat, the theme of the excursion is closely linked to environmental issues and a responsible approach to the use of natural...

L’évaluation du comportement animal est devenue un outil fondamental dans les champs de recherche des neurosciences translationnelles. Elle est en effet utile pour l’étude des mécanismes physiologiques entraînant les maladies neurodégénératives mais aussi pour la compréhension des modifications fonctionnelles induites par des manipulations génétiques ou traitement chimique et pour tester l’efficacité de composés ou molécules. Chez l’Homme, on utilise des batteries de tests cognitifs et moteurs pour qualifier et quantifier les atteintes des maladies neurodégénératives telles que les maladies d’Alzheimer et de Parkinson. Le travail présenté ici s’inscrit dans l’optique de promouvoir Microcebus murinus comme modèle pour l’étude des maladies neurodégénératives liées à l’âge. Le microcèbe est un petit primate lémurien, proche phylogénétiquement de l’Homme, présentant des particularités prometteuses susceptibles d’accélérer la découverte de nouveaux traitements curatifs et prophylactiques pour les pathologies liées à l’âge. La validation du modèle nécessite l’utilisation de tests comportementaux discriminant l’atteinte neurodégénérative. Nous avons mis au point un ensemble de tests comportementaux évaluant l’apprentissage, la mémoire et les fonctions motrices. Des animaux sains ont été évalués et ont permis de définir des protocoles spécifiques au microcèbe. Ces protocoles ont ensuite été appliqués à des animaux ayant subi un traitement pour induire des pathologies de type Parkinson ou Alzheimer afin de détecter l’apparition d’éventuels déficits. / Animal behavior has become a fundamental tool in translational neuroscience area and is useful for studying physiological mechanisms underlying neurological diseases and also for understanding the functional modifications induced by genetic manipulation or chemical treatment. The experiment of new treatments requires animal models miming the human pathology. In Humans batteries of cognitive and motor tests are used to qualify and quantify the impairment due to neurodegenerative disease as Alzheimer's disease and Parkinson’s disease. The aim of this work is to promote Microcebus murinus as a model of age related neurodegenerative pathologies. The grey mouse lemur, a small prosimian primate, phylogenetically close to Human, presents specific characteristics susceptible to provide important information on the validity and efficacy of new. The validation of a model requires the use of behavioral tests to discriminate neurodegenerative impairment. A set of behavioral tests were worked out to evaluate learning memory and motor functions. Healthy animals were evaluated and allowed to define protocols species specific. These protocols were then applied on animals treated to induce pathology such as Parkinson or Alzheimer in order to detect cognitive or motor impairments.

Os primatas neotropicais, ou primatas do novo mundo, são pertencentes a um grupo diverso e variado de animais, com características anatômicas, comportamentais e taxonômicas próprias, que os diferem dos primatas do velho mundo. Estima-se que representem 31% dos primatas não-humanos do planeta. Têm sofrido com as altas taxas de crescimento populacional e perturbação antrópica resultante do desflorestamento, agricultura e criação de gado. Com o intuito de reverter esta situação e maximizar o potencial reprodutivo das espécies, o desenvolvimento de biotecnologias associadas à reprodução tem sido amplamente justificado nos dias de hoje, por representarem importantes ferramentas reprodutivas, contribuindo para a preservação da biodiversidade e manutenção da diversidade genética. Assim, o objetivo do presente estudo foi padronizar a colheita de sêmen de Alouatta guariba clamitans por eletroejaculação por via retal com posterior análise do sêmen fresco, procedimentos nunca descritos para a espécie, e adaptar o método de preparo de sêmen de Leontopithecus chrysomelas, Alouatta caraya e Alouatta guariba clamitans para microscopia eletrônica de transmissão, permitindo a comparação da ultraestrutura dos espermatozoides das três espécies e apresentando resultados também inéditos na literatura científica. Para este estudo, foram utilizados quatro exemplares de L. chrysomelas, dois exemplares de A. caraya e dois exemplares de A.g. clamitans, machos adultos mantidos em cativeiro. L. chrysomelas tiveram o sêmen colhido por vibroestimulação peniana, e A. caraya e A.g. clamitans foram submetidos à eletroejaculação por via retal. Após a obtenção dos ejaculados, o sêmen foi avaliado quanto ao volume, pH, concentração, motilidade, integridade de membrana plasmática, integridade de membrana acrossomal e morfologia, e posteriormente preparado para microscopia eletrônica de transmissão. A análise dos 12 espermatozoides das três espécies estudadas revelou que todos apresentam os componentes básicos descritos para o espermatozoide humano cabeça, colo e cauda, formada pelas peças intermediária, principal e terminal com variações na forma e tamanho de cada componente. As diferenças mais significativas encontradas entre os espermatozoides comparados foram extensão de acrossomo, comprimento, largura e organização de peça intermediária. O presente estudo atingiu os objetivos propostos, apresentando resultados inéditos na literatura científica / The neotropical primates, also known as primates of the new world, are a diverse and varied group of animals, with unique anatomical and taxonomic characteristics, as well a unique behaviour, that distinguish those from the old world primates. It is estimated that these present 31% of the non-human primate population of the planet. High taxes of populational growth and anthropological disturbance have been undergoing due to deforestation, agriculture and cattle farms. In order to revert this situation and maximize the reproductive potential of the species, the development of biotechnologies associated to the reproduction are widely justified nowadays, for representing important reproductive tools, contributing to the preservation of the biodiversity and maintenance of genetic diversity. Hence, the purpose of this study was to collect Alouatta guariba clamitans semen by rectal electroejaculation then analyze the fresh semen, procedures never before described for the species, and adapt the preparation method of Leontopithecus chrysomelas, Alouatta caraya and Alouatta guariba clamitans semen for electron transmission microscope, allowing the comparison of the spermatozoa ultrastructure from the three species and also presenting new results to the scientific literature. For this study, it was used four specimens of L. chrysomelas, two specimens of A. caraya and two specimens of A.g. clamitans, adult males kept in captivity. L. chrysomelas had the semen taken by penine vibratory stimulation, and A. caraya and A.g. clamitans were submitted to rectal electroejaculation. After the semen was obtained, it was evaluated regarding the volume, pH, concentration, motility, sperm membrane integrity, acrosome integrity and morphology, and then prepared for electron transmission microscopy. The analysis of the spermatozoa of the three studied species revealed that all present the basic components described for the human spermatozoa - head, neck region and tail, formed by middle, principal and terminal pieces - with variations in 14 shape and size of each component. The most significant differences found between the compared spermatozoa were the acrosome extension and middle piece length, thickness and organization. The present study attained the proposed goals, presenting unprecedented results for the scientific literature

Is personality important for understanding the variation we see in animal welfare? In this thesis, I address that question by studying the association between personality and health, welfare, and happiness in three species of nonhuman primate: rhesus macaques (Macaca mulatta), brown capuchins (Sapajus apella), and chimpanzees (Pan troglodytes). As part of this research I test a newly designed animal welfare questionnaire. In Chapter 1 I review how animal welfare questionnaires can be designed and implemented as an addition tool for assessing animal welfare. In Chapter 2 I present a study of rhesus macaque personality, dominance, behaviour, and health. In Chapter 3 I test the reliability and validity of my animal welfare questionnaire. In Chapter 4 I extended my work on welfare questionnaires to test if they are valid for assessment of chimpanzee welfare and associated with personality. I specifically test if welfare ratings are based on observed behaviour. I conclude my quantitative work in Chapter 5 with a study testing the association between personality and health, welfare, and subjective well-being in rhesus macaques. Finally, Chapter 6 includes my conclusions and future directions for this line of research. Across all four quantitative studies some common trends were found. First, personality is associated with overall welfare and health. Second, welfare questionnaires are reliable and valid way to assess welfare in the studied species. And third, welfare and subjective well-being are measuring the same construct in these species. Overall, I conclude that personality is clearly useful for understanding animal welfare and that questionnaires are a reliable, valid, and valuable method of animal welfare assessment, in additional to traditional methods.

L'imagerie par résonance magnétique fonctionnelle (IRMf) permet d'examiner l'organisation fonctionnelle du cerveau humain de manière non-invasive et chez les sujets sains. L'implémentation de cette technique chez des primates non-humains représente un progrès important dans les neurosciences des systèmes. D'une part, l'IRMf singe permet la réduction et le raffinement des protocoles invasifs impliquant des primates non humains, en révélant les régions d'intérêts dans lesquelles les approches focales invasives, électrophysiologiques ou anatomiques, devraient être menées. D'un autre côté, les connaissances acquises avec ces approches invasives peuvent être transposées plus aisément à l'homme, une fois que les homologies et différences interspécifiques ont été identifiées au travers de protocoles d'IRMf menées en parallèle chez les primates humains et non- humains. La 1ère partie de cette thèse présente les approches conventionnelles d'étude des fonctions cérébrales. Nous montrons que des études invasives chez l'animal demeurent nécessaires pour comprendre les mécanismes neuronaux qui sous-tendent nos fonctions cognitives, malgré le progrès des techniques d'investigation chez l'homme. Suit une revue sur l'évolution des techniques d'IRMf singe et certaines de ses réalisations majeures comme pont dressé entre les études non-invasives menées chez l'homme et les études invasives réalisées chez l'animal, notamment en ce qui concerne notre compréhension des mécanismes neuronaux permettant la saisie manuelle d'objets sous contrôle visuel. Purement méthodologique, la fin de cette 1ère partie décrit l'animalerie et la plate-forme d'IRM à Toulouse et expose les jalons de l'implémentation de l'IRMf chez le singe macaque vigile. La 2ème partie de la thèse présente les 4 études que nous avons menées en IRMf singe. La 1ère étude modélise la réponse hémodynamique chez le singe, un outil indispensable à l'analyses de données d'IRMf, acquises dans les études suivantes. La 2ème étude traite de l'organisation visuotopique du cortex visuel dorsal des primates, et y décrit un nouvel assemblage d'aires visuotopiques chez 2 animaux, grâce à l'usage de nouvelles techniques de stimulation visuelle et d'analyse de champ récepteurs. Ces résultats apportent un point de vue neuf sur l'organisation fonctionnelle de la voie visuelle dorsale et ouvrent de nombreuses perspectives pour les comparaisons entre espèces. La 3ème étude cartographie le réseau d'aires corticales impliqué dans le traitement du flux optique chez les primates non humains et le compare à celui décrit récemment chez l'homme. Grâce à la réplication d'une étude réalisée chez l'homme, nous avons confirmé chez 3 macaques l'implication de zones précédemment identifiées par des enregistrements électrophysiologiques. Nos résultats révèlent de nouvelles zones corticales impliquées dans le traitement du flux optique, dessinant l'image d'un réseau cortical partageant de nombreuses similitudes, mais ayant également des différences frappantes, avec celui documenté dans le cerveau humain. En résumé, l'ambition de cette thèse est double : (1) fournir des recommandations pour la mise en place de techniques IRMf chez le singe, tirées de notre propre expérience et (2) exposer les résultats d'un ensemble d'études que nous avons menées avec cette approche, traitant de l'organisation visuotopique du cortex visuel dorsal et de son implication dans le traitement du mouvement visuel. En plus d'apporter une perspective nouvelle sur l'organisation fonctionnelle du cortex visuel chez les primates non humains, ces études illustrent la contribution de l'IRMf singe comme pont entre études électrophysiologiques chez les primates non humains et études d'imagerie fonctionnelle chez l'homme. / Functional magnetic resonance imaging (fMRI) allows addressing the functional organization of the human brain with minimal invasiveness and in healthy individuals. The implementation of that technique in non-human primates represents an important achievement in systems neuroscience. On the one hand, monkey fMRI contributes to the reduction and refinement of invasive approaches in non-human primates, by revealing the regions of interest in which focal electrophysiological and/or anatomical investigations should be carried out. On the other hand, the knowledge acquired with such invasive approaches can be more safely transposed to humans, once inter-species homologies and differences have been identified through the use of similar fMRI protocols in human and non-human primates. The first part of this thesis reviews the most common approaches that have been used to study brain functions, either in humans or in non-human primates. It is shown that despite progresses in the human approaches, invasive studies in monkeys remain necessary for understanding the neuronal mechanisms underlying cognitive functions. Then follows a description of the evolution of the monkey fMRI techniques and some of its achievements in bridging the gap between non-invasive human studies and invasive animal studies, notably for deciphering the neural mechanisms supporting visually-guided grasping. The end of this first part is purely methodological. It undertakes the description of the monkey facilities and the MR platform in Toulouse, and details the necessary milestones for conducting fMRI research in macaque monkeys. The second part of the thesis presents the 4 studies we have conducted with monkey fMRI. The first study is a preparatory experiment for characterizing the monkey hemodynamic response function, which is a prerequisite for proper analysis of subsequent monkey fMRI data. The second study addresses the visuotopic organization of the primate dorsal visual cortex with a novel technique of wide-field (80°) phase-encoded visual stimulation, coupled with a state of the art surface-based analysis of population receptive fields. The results obtained in 2 animals uncover a new cluster of visuotopic areas in the posterior parietal cortex of the macaque monkey, bringing a fresh view to the functional organization of this piece of cortex and opening a promising avenue for inter-species comparisons. The third study unveils the cortical network involved in optic flow processing in non-human primates and it compares this network to that recently described in humans. To that end, we replicated in macaque monkeys an experiment previously conducted in human subjects with optic flow stimuli that are either consistent or inconsistent with egomotion. Besides confirming the involvement of areas previously identified through electrophysiological recordings, our results reveal new cortical areas involved in the processing of optic flow, drawing the picture of a network sharing many similarities, but also striking differences, with that documented in the human brain. In summary, the ambition of this thesis is two-fold: (1) providing guidelines for setting-up monkey fMRI techniques, drawn from our own experience and (2) exposing a set of studies we have conducted with this approach, dealing with the visuotopic organization of the dorsal visual cortex and its involvement in the processing of visual motion. Besides bringing a fresh view to the functional organization of the dorsal visual pathway in non-human primates, these studies illustrate how monkey fMRI bridges the gap between electrophysiological studies in non-human primates and functional imaging studies in humans.

Considera-se que viver em grupo aumenta a probabilidade de transmissão de parasitos entre co-específicos, dada a maior proximidade e/ou frequência de interação entre os indivíduos. A transmissão de doenças entre diferentes espécies de hospedeiros, entre indivíduos de uma mesma espécie ou de um mesmo grupo social pode levar populações de animais selvagens ao declínio. Dada a relevância do tema, neste trabalho, buscamos contribuir para o entendimento dos fatores que afetam a ocorrência de parasitoses em primatas selvagens. Investigamos a ocorrência de parasitos intestinais em uma população selvagem de macacos-prego (Sapajus libidinosus), analisando os efeitos de três fatores distintos: proximidade geográfica entre primatas humanos e não humanos; características intrínsecas dos hospedeiros e climáticas do ambiente e, por fim, relações sociais diferenciadas. Encontramos que a sobreposição de área de vida não é suficiente para explicar a co-ocorrência de parasitos intestinais entre as diferentes espécies de hospedeiros na Fazenda Boa Vista (Piauí, Brasil). Ao considerarmos os efeitos dos hospedeiros e do ambiente sobre as parasitoses intestinais de acordo com o modo de transmissão dos parasitos, confirmamos que parasitos com diferentes ciclos de vida e modos de transmissão são afetados diferentemente por características dos hospedeiros e do ambiente: parasitos transmitidos diretamente foram afetados somente por características dos hospedeiros; parasitos transmitidos via hospedeiros intermediários foram afetados somente por características climáticas do ambiente, enquanto parasitos transmitidos via ambiente foram afetados por ambos (hospedeiros e ambiente). Por fim, ao investigarmos os efeitos das interações sociais sobre as parasitoses com base nos modos de transmissão dos parasitos, encontramos que a transmissão de parasitos, mesmo os com modo de transmissão direta, não depende exclusivamente da frequência de associação espacial entre os indivíduos. Os resultados deste trabalho contrariaram as principais premissas do efeito da socialidade sobre a transmissão de parasitos. Assim, é preciso considerar que a chance de aquisição e transmissão de parasitos em espécies sociais é complexa e está sujeita à interação de diversos fatores: individuais, ambientais e dos próprios parasitos, os quais, portanto, devem ser incorporados aos estudos de transmissão de doenças em populações de animais selvagens / Living in a group theoretically increases the probability of transmission of parasites between co-specifics, given the greater proximity and / or frequency of interaction between individuals. Transmission of diseases among different host species, among individuals of the same species or of the same social group, may lead to a decline in wild animal populations. Given the relevance of this research area, we seek to contribute in this thesis to the understanding of the factors that affect the occurrence of intestinal parasites in wild primates. We investigated the occurrence of intestinal parasites in a wild population of capuchin monkeys (Sapajus libidinosus), analyzing the effects of three distinct factors: geographical proximity between human and non-human primates; intrinsic host and environment climatic characteristics of the environment and, finally, differentiated social relationships. We found that the living area overlap is not sufficient to explain the co-occurrence of intestinal parasites between the different host species at Fazenda Boa Vista (Piaui State, Brazil). When we considered the effects of host and environmental characteristics on intestinal parasites according to the mode of transmission of the parasites, we confirmed that parasites with different life cycles and modes of transmission are differently affected differently: directly transmitted parasites were affected only by host characteristics; parasites transmitted via intermediate hosts were affected only by climatic characteristics of the environment, and parasites transmitted through the environment were affected by both host and environmental characteristics. Finally, when investigating the effects of social interactions on the occurrence of parasites according to parasite transmission modes, we found that the transmission of parasites, even those with direct transmission, do not depend exclusively on the frequency of spatial association between individuals. The results of this work contradict the main premises about the effect of sociality on the transmission of parasites. Thus, it is necessary to consider that the likelihood of acquisition and transmission of parasites in social species is complex and is subject to the interaction of several factors: individual, environmental and of the parasites themselves, which, therefore, must be considered in studies of disease transmission in wild animal populations

Orientador: Rosangela Zacarias Machado / Coorientador: Silvia Maria Fátima Di Santi / Banca: Solange Maria Gennari / Banca: Karin Werther / Resumo: Os Estados que compõem a Amazônia Legal respondem por 99% dos casos de malária humana registrados no Brasil. O Estado do Maranhão, atualmente, é responsável por 1% dos casos dessa região. Acredita-se que, na Região Amazônica ocorra a transmissão de malária de primatas para humanos, devido a relatos atuais de resultados soroepidemiológicos de humanos e primatas. O presente estudo objetivou realizar o diagnóstico morfológico, sorológico e molecular de Plasmodium spp. em primatas neotropicais na Ilha de São Luís, Estado do Maranhão, Brasil. Para tal, foram utilizadas como técnicas de diagnóstico: a microscopia de luz, a reação em cadeia pela polimerase (PCR) e a imunofluorescência indireta (RIFI). No período de junho de 2009 a abril de 2010, foram amostrados 70 primatas, sendo 50 provenientes do Centro de Triagem Animais Silvestres (CETAS), localizado no município de São Luís, e 20 de vida livre, capturados em reserva particular localizada no município de São José de Ribamar, Estado do Maranhão. Foram avaliadas pela microscopia de luz 140 lâminas (duas de cada animal), das quais cinco (7,1%) foram positivas. Pela RIFI não se detectou anticorpos anti-Plasmodium spp. Pela PCR, dos 70 animais amostrados, foi possível observar produtos amplificados para Plasmodium spp. em 13 amostras, das quais oito (61,54%) eram de animais de vida livre e cinco (38,46%) de CETAS. Pelo pequeno tamanho dos fragmentos dos produtos amplificados, foi necessário cloná-los em vetor pGEM-T Easy para sequenciamento, no entanto, não foram obtidos resultados confirmatórios / Abstract: The states that comprise the Amazon region are incriminated for 99% of registered cases of human malaria in Brazil. Currently, the state of Maranhão is responsible for 1% of cases in Amazonic region. According to recent seroepidemiological studies, the transmission of malaria from primates to humans occurs in Amazon region. Our study aimed to detect Plasmodium spp. in neotropical primate from island of São Luis, Maranhão State, Brazil, using morphological (light microscopy), molecular (Polymerase Chain Reaction [PCR]) and serological (Indirect immunofluorescence Assay [IFA]) techniques. Between June/2009 and April/2010, we sampled 70 primates, 50 from the Wildlife Screening Center (CETA), located in the city of São Luís, and 20 captured in a private reserve located in São José de Ribamar, state of Maranhão. Based on blood smear examinations, five (7.1%) monkeys were positive to Plasmodium spp. All animals showed seronegative to Plasmodium spp. by IFA. Plasmodium spp.-amplicons were detected in 13 animals; eight out of positive monkeys (61.54%) were free-ranging animals and five (38.46%) maintained in capitivity in CETAS. Regarding the small size of amplified fragments, we cloned the amplicons into pGEM-T Easy vector aiming at obtaining a higher sequencing quality; however, we did not reached satisfactory results / Mestre

Human and animal decision-making is known to violate rational expectations in a variety of contexts. Statistical structures of real-world environments may account for such seemingly irrational behavior. In a computerized experiment, 16 capuchins, 7 rhesus monkeys, and 30 humans chose between up to three options of different value. The options disappeared and became available again with different probabilities. Subjects overwhelmingly chose transitively (A>B, B>C, and A>C) in the control condition, where doing so maximized overall gain. However, most subjects also adhered to transitivity in the test condition, where it was suboptimal but led to negligible losses compared to the optimal strategy. Only a few of the capuchins were able to maximize long-term gain by violating transitivity. Adhering to rational choice principles may facilitate the formation of near-optimal decision rules when short- and long-term goals align. Such cognitive shortcuts may have evolved to preserve mental resources.

Muriquis-do-norte (Brachyteles hypoxanthus) são caracterizados pela filopatria entre os machos, a formação de grupos multi-macho/multi-fêmea e um sistema de acasalamento poligâmico, com alto grau de promiscuidade. No entanto, alterações ambientais (ecológicas ou demográficas) podem conduzir a modificações no sistema social (seja na estrutura social, organização social ou sistema de acasalamento) considerado como o típico da espécie. A formação de um grupo composto somente por machos (denominado UM), que se associa constantemente com um grupo misto, ou seja, multi-macho/multi-fêmea (denominado grupo Nadir), e a transferência de machos entre grupos distintos, são padrões comportamentais não descritos para os muriquis-do-norte da Estação Biológica de Caratinga, MG. Assim, esta pesquisa teve como objetivos: 1) analisar as interações sociais entre os machos da UM com os machos adultos do grupo Nadir, 2) comparar o comportamento dos machos UM com o comportamento dos machos adultos do grupo Nadir, e 3) analisar as relações sociais entre os machos adultos do grupo Nadir. Dezessete machos adultos foram alvo desta pesquisa, 8 indivíduos da UM e 9 do grupo Nadir. Os machos adultos do grupo Nadir foram divididos em: imigrantes (machos que se transferiram da UM para o grupo Nadir, 4 indivíduos), e residentes (machos fundaram o grupo Nadir, 5 indivíduos). Interações afiliativas, dinâmica espacial e vizinhos em diferentes categorias de distância espacial foram registrados pelo método animal focal. O método de todas as ocorrências foi empregado para o registro de cópulas e interações agonísticas. Os resultados demonstraram que apesar dos machos UM se associarem com o grupo Nadir, sendo constantemente observados na periferia ou até mesmo dentro do grupo, as interações sociais entre os machos UM e GN não se caracterizaram como relações sociais de indivíduos pertencentes ao mesmo grupo. Entretanto, as interações sociais dos machos UM com os machos GN não apresentaram um padrão homogêneo, sendo as interações com os imigrantes diferenciadas das interações com os residentes. Ao comparar o comportamento dos machos UM e GN, houve diferença significativa somente no padrão de associação espacial. A análise dos dados referente às relações sociais dos machos GN revelou uma assimetria, pois os imigrantes formaram associações mais fortes com os residentes do que entre si e foram os responsáveis pela manutenção de proximidade e interações afiliativas com os residentes. A tolerância entre os machos UM e machos GN, principalmente dos imigrantes, foi explicada pela familiaridade entre eles. Em relação às relações sociais entre os machos GN, inferi um status social diferenciado entre imigrantes e residentes, devido à maior atratividade que os residentes exerceram sobre os imigrantes. A capacidade de se adaptar a condições demográficas específicas, variando sua organização e estrutura social, evidencia a flexibilidade comportamental da espécie. / Northern muriquis (Brachyteles hypoxanthus) are characterized by male philopatry, by multi-male/multi-female groups and by a polygamous mating system, with high levels of promiscuity. Nevertheless, environmental changes (ecological or demographic) can lead to changes in the social system (in the social structure, as well as in the social organization, or in the mating system) considered as typical of the species. Behavioural patterns such as the formation of an all male group (called UM), constantly associated with a multi-male/multi-female group (called Nadir group), and the transfer of males between distinct groups, are not described yet for northern muriquis of the Estação Biológica de Caratinga, MG. Therefore, the aims of this research were: 1) to analyse the social interactions between the UM males and the adult males of the Nadir group, 2) to compare the behaviour of UM males and the behaviour of adult males of the Nadir group, and 3) to analyse the social relationships among the adult males of the Nadir group. Seventeen adult males were the subjects of this research, 8 individuals belonged to the UM and 9 belonged to the Nadir group. The adult males of Nadir group were separeted into: immigrant (males that transfer from UM to Nadir group, 4 individuals), and resident (males that founded the Nadir group, 5 individuals). Afilliative interactions, spacial dynamics and neighbours at different categories of spacial distances were registered by focal animal sampling. The all occurrences sampling was used to record episodes of copulation and agonistic interactions. The results indicated that the social interactions between UM e GN males did not characterize social relationships between members of the same group, even though the UM males associated with the Nadir group, being often observed at the border or even inside the group. The interactions between males of the two groups did not obey a unique pattern. The interactions with immigrant males were different from those with resident males. The comparison between the UM and GN male behaviour revealed significant differences only in the pattern of spatial association. The analysis of GN males social relationships revealed an asymmetry, because the immigrants had stronger associations with residents than among themselves and were the responsible for approaching and for mantaining afilliative interactions with residents. GN males, particularly immigrants, were tolerant towards UM males, probably due to the familiarity among them. Regarding the social relationships among GN males, it was possible to distinguish the social status between immigrants and residents, since resident males were highly attractive to the immigrant males. The adaptive capacity to adjust to specific demographyc conditions, trough changes in the social organization and structure, highlights the behavioural flexibility of the species.