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De nombreuses études s’intéressent aux comportements décisionnels et d’apprentissage ainsiqu’aux structures qui les sous-tendent. Il a été montré que le Cortex Préfrontal (CPF) ainsiqu’un réseau de structures sous-corticales, les Ganglions de la Base (GB), étaient impliquésdans ces processus. Néanmoins, le rôle respectif de chacun n’est pas définit. Deux hypothèsessont émises. La première stipule que les deux structures fonctionnent indépendamment. LesGB seraient impliqués dans les comportements habituatifs tandis que le CPF se chargerait descomportements planifiés. La seconde hypothèse considère que les deux structures collaborent: les GB contrôleraient un processus d'apprentissage à cinétique lente dans le CPF et sedésengageraient progressivement au fur et à mesure de l’apprentissage. Ceci reviendrait d'unecertaine façon à inverser les rôles : les GB seraient nécessaires aux processus de décision tantque le CPF n'aurait pas fini son apprentissage. Celui-ci fonctionnerait ensuite sur un modeautomatique. Le principal obstacle à l’étude respectif du rôle des GB et du CPF dans cesprocessus intervient dans les paradigmes expérimentaux qui ne dissocient pas la prise dedécision per se des processus d’apprentissage. Notre premier objectif a donc été d’élaborerune tâche expérimentale qui permette de différencier les phases d’apprentissage des phases deprise de décision. Nous avons ensuite supprimé l'influence des GB sur le cortex, en inhibantleur structure de sortie, le Globus Pallidus interne (GPi) par des injections intracérébrales demuscimol chez le primate non-humain effectuant une tâche comportementale : le "two armedbandit task". Nous montrons que les animaux sont toujours capables de prendre des décisionsaprès inhibition du GPi mais qu’ils sont incapables d’apprendre la valeur de nouvelles cibles.Ces résultats confirment que, chez le primate en tous les cas, les GB et le CPF sont bienimpliqués dans un processus collaboratif : l'intégrité de l'ensemble du circuit est nécessairepour l'apprentissage alors que le cortex seul peut suffire une fois que le choix se situe dans uncontexte habituel. / Many studies are interested in decision making and learning processes and in brainareas which are engaged in. Among them, the implication Prefrontal Cortex (PFC) and a subcortical structures’ network, the Basal Ganglia (BG) has been shown. Nevertheless, theprecise role of each structure has not yet been defined. There are two main hypotheses. Thefirst one holds that GB and PFC function independently. BG would support habitualbehaviors and PFC planned behaviors. The second hypothesis proposes that both structuresare collaborating: the basal ganglia drive a low kinetic learning process in the prefrontalcortex and become less and less engaged as the task is learned. It means reversing the roles:BG would be necessary for decision making processes as soon as PFC finishes its learning.This latter would then function as an automatic mode. The main problem which avoids us todisentangle the role of each structure is the experimental paradigms used which mix uplearning and decision making. Our first aim was to design an experimental task in which therewas learning phase and decision making phase per se. Then, we blocked basal gangliainfluence on PFC by inhibiting their exit structure, the Globus Pallidus internal, withintracerebral muscimol injections in non-human primates performing a “two-armed bandittask”. Our results show that monkeys are able to do decision making after GPi inhibition butthey are unable to learn new values. These results confirm that, in non-human primates, BGand PFC are well involved as co-workers in one process: integrity of all the circuit isnecessary for learning whereas only cortex is sufficient once the choice is in habitual context.

Il est classiquement admis que les études comparatives sur la communication des animaux peuvent permettre de mieux comprendre la coévolution de la vie sociale, de la communication vocale et des capacités cognitives, notamment l’émergence de certaines propriétés du langage humain. De récentes études ont suggéré la présence de capacités combinatoires chez les primates non humains, capacités qui permettraient à ces animaux de diversifier leurs répertoires ou d’enrichir les messages transmis par leurs vocalisations en dépit de capacités articulatoires limitées. Toutefois, les fonctions des cris combinés et les informations qui en sont extraites par les receveurs restent méconnues. Cette thèse porte sur les capacités de combinaison vocale de cercopithèques forestiers sauvages : la mone de Campbell (Cercopithecus Campbelli) et le singe Diane (Cercopithecus Diana). Premièrement, à l’aide d’expériences de repasse acoustiques, j’ai étudié la nature combinatoire de cris combinés et les informations qui en sont extraites par les receveurs chez ces deux espèces. Les résultats ont confirmé chez les mâles mone de Campbell la présence d’un mécanisme de suffixation diminuant l’urgence du danger signalé par un cri d’alarme ainsi que, chez les femelles singe Diane, la présence de cris complexes combinant linéairement les messages des deux unités qui les composent, signalant respectivement l’émotion et l’identité de l’émetteur. Deuxièmement, une étude observationnelle du contexte d’émission de cris simples et combinés par des femelles mones de Campbell sauvages a révélé une utilisation flexible de la combinaison en fonction du besoin immédiat de rester discret (i.e. cris simples) ou de signaler son identité (i.e. cris combinés). Finalement, j’ai comparé les systèmes de communication des femelles de ces deux espèces pour identifier leurs points communs et leurs différences. Leurs répertoires sont basés principalement sur des structures acoustiques homologues, comme prédit par leur proximité phylogénétique. Cependant, les femelles de ces deux espèces diffèrent fortement dans leur utilisation de ces structures. Par exemple, le grand nombre de cris combinés chez les singes Diane semble permettre un accroissement considérable de leur répertoire vocal par rapport aux mones de Campbell. Etant donné l’organisation non-aléatoire de ces combinaisons vocales qui font sens pour les receveurs et de leur utilisation flexible en fonction du contexte, je propose un parallèle avec une forme simple de morphosyntaxe sémantique et discute aussi plus généralement de la possibilité de trouver des capacités similaires chez d’autres espèces animales. / It is generally accepted that comparative studies on animal communication can provide insights into the coevolution of social life, vocal communication, cognitive capacities and notably the emergence of some human language features. Recent studies suggested that non-human primates possess combinatorial abilities that may allow a diversification of vocal repertoires or a richer communication in spite of limited articulatory capacities. However, the functions of combined calls and the information that receivers can extract remain poorly understood. This thesis investigated call combination systems in two species of guenons: Campbell’s monkey (Cercopithecus Campbelli) and Diana monkey (Cercopithecus Diana). Firstly, I studied the combinatorial structure and relevance to receivers of combined calls in of both species using playback experiments. Results confirmed the presence of a suffixation mechanism reducing the emergency of danger signaled by calls of male Campbell’s monkeys. Also, they showed that combined calls of females Diana monkeys convey linearly information via their two units, which signal respectively caller’s emotional state and identity. Secondly, focusing on the context associated with the emission of simple and combined female Campbell’s monkey calls, results revealed flexible use of combination reflecting the immediate need to remain cryptic (i.e. simple calls) or to signal caller’s identity (i.e. combined calls). Finally, I compared females’ communication systems of both species to identify their similarities and differences. As predicted by their close phylogenetic relatedness, their repertoires are mostly based on homologous structures. However, the females differ strongly in their use of those structures. In particular, the great number of calls combined by Diana monkeys increases considerably their vocal repertoire compared to Campbell’s monkeys. Given that the combinations are non-random, meaningful to receivers and used flexibly with the context, I propose a parallel with a rudimentary form of semantic morphosyntax and discuss more generally the possible existence of similar capacities in other non-human animals.

Orientadora: Eleonore Zulnara Freire Setz / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T18:03:19Z (GMT). No. of bitstreams: 1 Gestich_CarlaCristina_M.pdf: 2412818 bytes, checksum: 3850c0adff0e3465f46c136d4a4903b3 (MD5) Previous issue date: 2012 / Resumo: A alteração das necessidades energéticas dos endotérmicos pela variação da temperatura ambiental devido aos custos da termorregulação pode influenciar seu comportamento. O objetivo desse estudo foi investigar a influência da temperatura nos comportamentos de sauás (Callicebus nigrifrons) na Serra do Japi, região com marcada sazonalidade e temperatura reduzida pela altitude. Para isso, relacionamos com a temperatura: o padrão de atividade, os itens alimentares e os comportamentos termorregulatórios durante o descanso (seleção de micro-hábitat, contato entre os indivíduos e postura corporal). Quanto menores as temperaturas mínimas noturnas, o que pode representar estresse térmico, os sauás iniciaram suas atividades mais tardiamente, no momento em que a temperatura ambiental já estava elevada. A distância percorrida diariamente não variou com a temperatura, mas os sauás locomoveram mais no início do dia, horário mais frio, coincidindo com o início das atividades. Entre os meses, a locomoção foi menor nos mais frios, possivelmente resultando em economia de energia. Não houve seleção por itens alimentares mais calóricos em temperaturas baixas. Entretanto, houve aumento no forrageio nos meses mais frios (não relacionado com a disponibilidade de frutos), compatível com a ideia de que os custos da termorregulação podem influenciar a ingestão de alimentos. A seleção de locais ao sol foi maior em temperaturas baixas, e tal comportamento pode estar reduzindo os custos da termorregulação com o aumento da absorção de calor da radiação solar. O contato entre os indivíduos ao longo do dia não teve relação com a temperatura e pode ter sido influenciado somente pelas interações sociais. A postura não variou em função da temperatura e aquelas que resultavam em menor perda de calor para o meio foram predominantemente adotadas. Isso, provavelmente, devido ao porte pequeno da espécie (elevada razão superfície/volume) que contribui para maior perda de calor nas baixas temperaturas registradas. Conclui-se que os sauás apresentam variação comportamental em função da temperatura ambiental quanto à escolha de micro-hábitats e padrão de locomoção e forrageio / Abstract: Variations in ambient temperature can change the energy requirements of endothermics due to costs of thermoregulation. So, ambient temperature can influence animal's behavior. The aim of this work was to investigate ambient temperature influence on wild black-fronted titi monkeys (Callicebus nigrifrons) behavior. We conducted this study in Serra do Japi, region with marked seasonality and temperature reduced due to high altitude. We analyzed the relation between temperature and the following variables: activity pattern, types of food consumed and thermoregulatory behaviors observed during resting (microhabitat selection, contact between individuals and body posture). In lower night minimum temperatures, which may represent thermal stress to titi monkey, they started their activities later in the day, after ambient temperature increase. There was no correlation between path length and ambient temperature, but titis moved more at beginning of the day (at the coldest hours), when they were starting these activities. During the coldest months, titis moved less, which could be a strategy to save energy. During this period, they did not select higher-calorie food items, but there was an increase in foraging behavior (not related to fruit availability), which is consistent with the idea that the energy costs of thermoregulation can influence food intake. The sunny resting places were selected at low temperatures. This behavior could be used to reduce thermoregulation costs, allowing the increase of heat absorption from solar radiation. The contact between individuals throughout the day was not related to the temperature and may be influenced only by social interactions. Body postures were not influenced by ambient temperature and postures that avoid heat loss were predominantly adopted. This is probably due to the small size of the species (considering the high surface/volume ratio) which contributes to greater heat loss at low temperatures. We concluded that titi monkey's behaviors vary in function of ambient temperature, such as microhabitat choice and pattern of moving and foraging / Mestrado / Ecologia / Mestre em Ecologia

Landscape genetics is an emerging field that seeks to understand how specific landscape features and microevolutionary processes such as gene flow, genetic drift, and selection interact to shape the amount and spatial distribution of genetic variation. This study explores, through agent based simulations, how the specific mating and social system of tamarin primates (genus Saguinus) influences population genetic structure and patterns of relatedness within and among groups of this primate species, which might affect the ability of landscape genetic studies to detect the effects of fragmentation on gene flow. I use a spatially-explicit agent-based population genetics simulation model (GENESYS) configured to reflect the particular social system of tamarin monkeys (i.e. small group size, limited numbers of breeders per group, frequent twin births, and short dispersal distances) to assess whether the isolation by distance model of genetic differentiation expected in an unfragmented landscape can be distinguished from the isolation by barrier model expected in a fragmented landscape. GENESYS allows a user to explore the effects of social structure and landscape features on the population genetic structure of social animals, such as primates. I simulated two different landscapes containing an otherwise equivalent population of tamarins. In the first setup I simulated a homogeneous landscape unconstrained by any barriers to gene flow, while for the second setup, a barrier to gene flow restricted dispersal from one half of the landscape to the other. I found that the particular mating system of tamarin results in the rapid genetic differentiation of its social groups and consequently its populations. Social groups in the continuous landscape indeed revealed an isolation by distance pattern, while social groups on the fragmented landscape yielded instead an isolation by barrier model, where the barrier rather than geographic distance per se influenced the spatial genetic structure of the population. The results from this study suggest that features of the tamarin social system influence population genetic structure, which could affect the ability of landscape genetic studies to detect the effects of fragmentation on gene flow. To more fully address that issue, future studies should focus on a range of different primate social systems. / text

Hominoid primate species differ remarkably in their social grouping and mating systems, notably including differing degrees of post-copulatory sexual selection. As the mating system of extinct hominins remains unknown and difficult to predict, it may be useful to examine more proximate phenotypes correlated with behavior. For example, chimpanzees and bonobos have a large ejaculate that coagulates into a rigid copulatory plug, presumably in response to high levels of sperm competition, while gorillas have a small semi-viscous ejaculate associated with low sperm competition. To understand the molecular basis responsible for differences in semen biochemistry among hominoid species, I completed two research projects. First, by cloning the upstream putative promoters of the chimpanzee, bonobo, human, and gorilla prostatic acid phosphatase (ACPP) genes into luciferase reporter vectors followed by transient transfections into a human prostate cell line, I identified the underlying nucleotide changes that reduce expression of this protein in chimpanzee semen. Second, by mapping large deletions at the kallikrein-related peptidase (KLK) locus in the gorilla and gibbon genomes, I characterized the convergent gene loss and the formation of a novel chimeric gene in these monandrous species. For both the ACPP and KLK locus changes, I determined the polarity of the changes through outgroup comparison. At ACPP, the reduced expression in chimpanzee and bonobo is derived, and likely in response to the onset of intense sperm competition in the common ancestor of these two species. If this biochemical phenotype is indeed a proxy for mating behavior, my data provides some evidence (to be compared and contrasted with other molecular, behavioral, and paleontological data) that the last common ancestor of humans and chimpanzees was not chimp-like in its high degree of polyandry. / Bayer School of Natural and Environmental Sciences; / Biological Sciences / PhD; / Dissertation;

Dental morphology and tooth shape have been used to recreate the dietary adaptations for extinct species, and thus dental variation can provide information on the relationship between fossil species and their paleoenvironments. Variation in living species with known behaviors can provide a baseline for interpreting morphology, and behavior, in the fossil record. Tooth occlusal surface outlines in hominins and non-hominin primates, and other mammals, have been used for assessments of taxonomic significance, with variability often considered as being primarily phylogenetic. Few studies have attempted to assess how diet might influence the pattern of variability in closely related species. Here the occlusal surface shape variability in anterior and postcanine maxillary dentition in primates is measured to assess whether the relationship between diet and variability is consistent. Data were collected from five non-hominin primates in a range of dietary categories, as well as two hominin species, including the derived Paranthropus robustus and a gracile australopith. Mapping a series of 50 sliding semilandmarks based on 2-D photographs using tpsDig software, occlusal surfaces were outlined. Thereafter, outline shapes were quantified using Elliptical Fourier Functional Analysis, and principle components and multivariate analyses were preformed to explore the pattern of intra and interspecific variability in occlusal outlines.These results suggest that there is not a clear relationship between dietary feeding adaptations for all categories examined and selection for larger premolars and molars, as well as smaller incisors, led to less variation in both anterior and post-canine teeth of the fossil hominin Paranthropus robustus.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

The link between cognitive challenge and captive animal well-being has received increased interest over the past decade, but so far this link in zoo animals has been overlooked. This is particularly surprising for chimpanzees (Pan troglodytes) and bottlenose dolphins (Tursiops truncatus) because these two 'large-brained' species have been the subjects of intensive cognitive research in captivity over the past six decades. In this thesis, I ask whether novel maze-like devices which aim to be cognitively challenging (abbreviated to 'devices with a cognitive component', DCCs) can be enriching for a mixed-sex group of chimpanzees and two single-sex groups of dolphins housed in zoos. I design, implement and evaluate two DCCs, and employ a new definition of cognitive enrichment that incorporates cognitive challenge and indicators of positive well-being. I demonstrate that two types of DCC for chimpanzees, one constructed from a grid of transparent cells and one from an array of opaque pipes, could be mastered using a number of problem-solving strategies (Chapter 5 and 6). DCC-use by chimpanzees increased when the DCC was less predictable (Chapter 5), but the relationship between self-directed behaviour and cognitive challenge was not straightforward (Chapter 6). In dolphins, only male subjects used an underwater DCC constructed from an array of opaque pipes, and could reflect a general sex difference in response to a novel situation (Chapter 7). In general, the chimpanzees and dolphins groups I studied showed some signs of enhanced well-being, for example increased environmental exploration and play, during exposure to DCCs. However, other behavioural responses such as increased vigilance in dolphins were difficult to interpret and did not suggest that DCCs were enriching. Both species 'worked' in the absence of food rewards and their success on the tasks (i.e. the removal of food or non-food rewards) had little effect on wellbeing indicators (Chapter 5 - 7). Finally, I demonstrate that lateralised behaviour (preference to perform behaviour using one side of the body) can be incorporated into the study of cognitive enrichment (Chapter 8).

Retrovírus endógenos (ERVs) são vírus que infectaram células germinativas e proliferaram no genoma do hospedeiro. A família K está integrada apenas no genoma de primatas do Velho Mundo. Os ERVs promovem alterações estruturais nos genomas hospedeiros, sendo fundamentais para a sua evolução. Esse trabalho teve como objetivo realizar uma investigação da distribuição e dinâmica evolutiva de ERV-K nos diferentes hospedeiros. Foram identificados 58 ERV-K em humanos, 38 em chimpanzés, 35 em orangotangos e 19 em macaco rhesus. Análises filogenéticas evidenciaram dois grupos principais, Grupo O/N, que compreende os provirus mais antigos e os mais recentes, e Grupo I, com provirus com tempo de integração intermediário. A dinâmica de espalhamento de ERV-K diferiu entre os hospedeiros. A fixação e eliminação dos ERV-K é resultado de fatores demográficos e populacionais, como gargalos de garrafa e expansões sofridas ao longo da evolução. Análises de quais provírus são ativos em pacientes com HIV e com cancer demonstrou que distintos ERVs são transativados, sugerindo alguma consequencia biológica para o hospedeiro. Além disso, a atividade dos ERVs não depende exclusivamente do tempo de integração, mas sim da integridade de regiões específicas contidas na LTR. / Endogenous retroviruses (ERVs) are remains of ancient viral infection in the germ line cells and subsequent vertical transmission. The K family are integrated only in humans and the Old World monkeys. ERVs play a fundamental role on genome evolution and foster variability. The aim of this work was to investigate their distribution and evolutionary dynamics in primate hosts. We found 55 ERV-K genomes in the human genome, 38 in chimpanzee, 35 in orangutan and 19 in Rhesus monkey. Two main groups were recovered by phylogenetic inference, Group O/N, comprising the newest and the oldest proviruses and, Group I, enclosing those with intermediate integration time. Although the primary integration took place in the ancestral lineage of all primates investigated, their evolutionary dynamic was different among them. I propose that ERV-K dynamics depends on the host demography experienced throughout their evolution. This work also investigated the putative source of proviral transcripts detected in HIV carries and cancer patients. The differential expression found under these conditions suggested a biological role of the ERV-K overexpression. Finally, the results showed that the ERV-K overexpression depends on the integrity of specific promoters in their LTR.