The aim of the study was to describe the reproductive biology of wild chimpanzees (Pan troglodytes schweinfurthi) and to relate this to aspects of their ecology and social organisation. Within this general framework the specific aims were: (a) To determine the reproductive potential of female chimpanzees and to assess the limits this places on species' reproduction; (b) To examine the adaptive significance of female reproductive physiology in terms of optimal reproductive success; (c) To examine environmental constraints on reproduction; (d) To describe copulatory behaviour and the nature of the three mating patterns shown by wild chimpanzees, and to assess the adaptive significance of the flexible mating system; (e) To relate reproductive behaviour to social organisation in an attempt to assess the role of sexual selection in the evolution of chimpanzee social behaviour and structure.

Due to high levels of exploitation, habitat loss and habitat degradation, Pan troglodytes has experienced such a significant population reduction over the past 20 to 30 years that it is now on the IUCN (International Union for the Conservation of Nature and Natural Resources) Red List of Endangered Species. The Nigerian chimpanzee, Pan troglodytes ellioti (Gray 1862), is the most endangered of the four subspecies of chimpanzee. It has the smallest distribution and smallest population size, estimated in 2011 to be between 3,500 – 9,000 individuals. P. t. ellioti was first recognized as a distinct subspecies in 1997, and in 2008 an Action Plan Study Group was set up with the goal to determine the priority sites for its conservation and the actions that should be taken to ensure its long-term survival. The Action Plan was published in 2011 and this thesis is timely as it begins to answer some of the questions deemed important in the action plan. The overall aim of this study was to explore the ecology and behaviour of a small, isolated montane population of P. t. ellioti with the aim of making a useful contribution to future recommendations for the management and conservation of this subspecies. Specifically, I estimated the density of chimpanzees in Ngel Nyaki Forest Reserve, Taraba State, Nigeria and investigated their nesting ecology, elementary technology, diet, seed dispersal and the viability of seeds dispersed by the chimpanzees. I estimated chimpanzee density by using a combination of direct (direct observation) and indirect methods using nest counts. My investigation of nesting ecology concentrated on identifying habitat variables that influenced choice of nesting site. I assessed elementary technology by locating and describing both manufactured artefacts and unmanufactured objects, and I then located evidence from the surrounding environment to establish details about their presence or absence. Chimpanzee diet was assessed using evidence from faecal samples and artefacts. In order to identify preferences and agents involved in removal of various seed species ingested and dispersed by chimpanzees I set-up a series of experiments using plots into which seed piles were added. Lastly, I compared the rate of germination of conspecific seeds which had been passed through a chimpanzee gut with those that had not been dispersed.

Thesis (doctoral)--Lund University, 1999. / Includes bibliographical references (p. 287-306). Also available on the Internet.

No description available.

Les asimetries funcionals manuals han estat àmpliament estudiades en els primats no humans i altres espècies animals durant les últimes dues dècades. Resulta especialment interessant observar si l'especialització hemisfèrica cerebral, tan característica de l'ésser humà, està o no present i en quin grau dins del regne animal. En ximpanzés, trobem pocs treballs en què s'hagin avaluat les preferències manuals en una única mostra des d'un punt de vista observacional i experimental conjuntament, i cap en ambients intermedis (naturalitzats). El nostre objectiu ha estat comparar els patrons de preferència manual en situacions espontànies i experimentals en una mateixa mostra de ximpanzés i veure quines situacions incideixen sobre la direcció, intensitat i grau d'asimetria individual versus poblacional en els individus. En la fase observacional es van estudiar 53 comportaments espontanis unimanuals i bimanuals que feien referència a contextos tròfics, manipulatius-exploratoris, autodirigits, posturals i socials, entre d'altres. En la fase experimental es van avaluar dues tasques: una unimanual (simple reaching: recollida d'ítems petits d'aliment amb prensions de precisió) i una altra bimanual (tube task: extracció bimanual d'aliment d'un tub). Durant la fase observacional es van dur a terme 2.226 sessions (2005 a 2008: 33 mesos). La fase experimental va tenir una durada total de 4 mesos (2007). La mostra estava formada per un grup de 14 ximpanzés (Pan troglodytes) allotjats al Centre de Recuperació de Primats de la Fundació Mona (Girona). En ambdues fases es va utilitzar un mostreig focal amb registre activat per transicions. Globalment, tant durant la fase observacional com experimental, la major part de la mostra va presentar preferències individuals laterals de manera significativa. Es van comparar els índexs de lateralitat per a les quatre condicions d'estudi: unimanual-espontani (UES), bimanual-espontani (BES), unimanual-experimental (UEX) i bimanual-experimental (BEX). No es van trobar diferències en la direcció de les preferències entre les quatre condicions tot i que sí en la intensitat de la lateralització. D'aquesta manera, la intensitat de la preferència manual era major en les accions bimanuals que en les unimanuals, i també en les tasques experimentals que en les espontànies. L'ús d'instruments i el tipus de prensió també van augmentar la intensitat de les preferències encara que no van tenir cap efecte sobre la direcció d'aquestes. Es va detectar una asimetria dretana poblacional en les accions bimanuals espontànies però no en les experimentals. També es va detectar una asimetria dreta a nivell poblacional en tenir en compte totes les tasques conjuntament. D'aquesta manera, ha estat la primera ocasió que s'evidencia que els ximpanzés allotjats en ambients intermedis són dretans a nivell poblacional. En conclusió, els ximpanzés presentarien un patró de lateralització homòleg al dels éssers humans, sobretot en aquelles accions que impliquen una complexitat en la seva execució (bimanualitat, instrumentalitat i precisió) i que són les més rellevants per entendre el procés d'hominització conductual d'aquest tret a Homo sapiens. / Las asimetrías funcionales manuales han sido ampliamente estudiadas en los primates no humanos y otras especies animales durante las últimas dos décadas. Resulta especialmente interesante observar si la especialización hemisférica cerebral, tan característica del ser humano, está o no presente y en qué grado dentro del reino animal. En chimpancés, encontramos pocos trabajos en los que se hayan evaluado las preferencias manuales en una única muestra desde un punto de vista observacional y experimental conjuntamente, y ninguno en ambientes intermedios (naturalizados). Nuestro objetivo ha sido comparar los patrones de preferencia manual en situaciones espontáneas y experimentales en una misma muestra de chimpancés y ver qué situaciones inciden sobre la dirección, intensidad y grado de asimetría individual versus poblacional en los individuos. En la fase observacional se estudiaron 53 comportamientos espontáneos unimanuales y bimanuales que hacían referencia a contextos tróficos, manipulativos-exploratorios, autodirigidos, posturales y sociales, entre otros. En la fase experimental evaluaron dos tareas: una unimanual (simple reaching: recogida de ítems pequeños de alimento con prensiones de precisión) y otra bimanual (tube task: extracción bimanual de alimento de un tubo). Durante la fase observacional se llevaron a cabo 2226 sesiones (2005 a 2008: 33 meses). La fase experimental tuvo una duración total de 4 meses (2007). La muestra estaba formada por un grupo de 14 chimpancés (Pan troglodytes) alojados en el Centro de Recuperación de Primates de Fundación Mona (Girona). En ambas fases se utilizó un muestreo focal con registro activado por transiciones. Globalmente, tanto durante la fase observacional como experimental, la mayor parte de la muestra presentó preferencias individuales laterales de manera significativa. Se compararon los índices de lateralidad para las cuatro condiciones de estudio: unimanual-espontáneo (UES), bimanual-espontáneo (BES), unimanual-experimental (UEX) y bimanual-experimental (BEX). No se encontraron diferencias en la dirección de las preferencias entre las cuatro condiciones aunque sí en la intensidad de la lateralización. De esta manera, la intensidad de la preferencia manual era mayor en las acciones bimanuales que en las unimanuales, y también en las tareas experimentales que en las espontáneas. El uso de instrumentos y el tipo de prensión también aumentaron la intensidad de las preferencias aunque no tuvieron ningún efecto sobre la dirección de éstas. Se detectó una asimetría diestra poblacional en las acciones bimanuales espontáneas aunque no en las experimentales. También se detectó una asimetría diestra a nivel poblacional al tener en cuenta todas las tareas conjuntamente. De esta manera, ha sido la primera ocasión que se evidencia que los chimpancés alojados en ambientes intermedios son diestros a nivel poblacional. En conclusión, los chimpancés exhibirían un patrón de lateralización homólogo al de los seres humanos, sobre todo en aquellas acciones que implican una complejidad en su ejecución (bimanualidad, instrumentalidad y precisión) y que son las más relevantes para entender el proceso de hominización conductual de este rasgo en Homo sapiens. / Manual functional asymmetries have been extensively studied in nonhuman primates and other animals for the last two decades. It is particularly interesting to see if brain hemispheric specialization, so characteristic human beings, is present or not and to what extent within the animal kingdom. In chimpanzees, there are few studies that have assessed hand preferences in a single sample from an experimental and observational standpoint, and none have been done within intermediate (naturalized) environments. Our objective was to compare the patterns of hand preference for spontaneous and experimental actions in the same sample of chimpanzees and observe what situations impact on the direction, strength and the degree of individual versus population asymmetry in individuals. In the observational phase, we studied 53 spontaneous unimanual and bimanual behaviors related to feeding contexts, manipulative-exploratory, self-directed, postural and social, among others. In the experimental phase, we evaluated two tasks: unimanual (simple reaching: collection of small items of food with precision grips) and bimanual (tube task: bimanual removal of food from a tube). During the observational phase, we conducted 2.226 sessions (from 2005 to 2008: 33 months). The experimental phase lasted a total of four months (2007). The sample was composed of a group of 14 chimpanzees (Pan troglodytes) housed at the Mona Foundation Primate Rehabilitation Center (Girona). In both phases, a focal sampling method was used. Overall, during both observational and experimental phases, the majority of the sample showed significant individual lateral preferences. We compared the handedness index for four study conditions: unimanual-spontaneous (UES), bimanual-spontaneous (BES), unimanual-experimental (UEX) and bimanual-experimental (BEX). There were no differences in the direction of preferences among the four conditions, but there were differences in the strength of lateralization. The strength of hand preference was higher in bimanual than in unimanual ones, and also in the experimental tasks than in the spontaneous ones. The use of tools and the type of grip also increased the strength of preferences, but had no effect on the direction of such preferences. We detected right-handedness at population-level for spontaneous bimanual actions, but not for the experimental ones. There was also a right asymmetry at the population level when considering all the tasks together. In this way, this was the first evidence that chimpanzees housed in an intermediate environment demonstrate right-handedness at population-level. In conclusion, chimpanzees exhibit a pattern of lateralization homologous to human beings, especially those actions that involve a complexity of execution (bimanual, tool use and precision grip) and that are most relevant for understanding the behavioral process of hominization of this trait in Homo sapiens.

Malgré la multiplicité des études démontrant le comportement fascinant des animaux dans leur milieu naturel, quelques domaines de recherches demeurent difficiles à aborder. Ainsi, l’étude de certains aspects cognitifs nécessite un certain contrôle sur l’environnement afin de dissocier les influences écologiques et sociales de l’implication cognitive ; par exemple la cognition spatiale incluant la mémoire spatiale, les mécanismes d’orientation spatiale, ainsi que leur implication dans la navigation, tel que par la planification. L’étude de la cognition spatiale des chimpanzés sauvages s’est déroulée dans le Parc national de Taï, une forêt tropicale dense où les ressources potentielles sont abondantes et réparties sur un territoire de 25 km², avec une visibilité d’environ 30 mètres. De plus, les chimpanzés vivent dans une société du type fission-fusion, impliquant de multiples relations sociales. Toutefois, l’enregistrement précis de la position et des activités des chimpanzés, ainsi qu’une carte botanique précise, nous a permis de dissocier les effets écologiques, sociaux et cognitifs afin de mieux comprendre les relations entre ces différents facteurs. Par cette étude, nous montrons que les chimpanzés ont développé un mécanisme permettant une navigation précise grâce à une carte Euclidienne contenant des informations sur la direction et la distances vers des ressources connues. Ce mécanisme est extrêmement adapté et efficace par la connaissance précise de la localisation de milliers de ressources dans leur habitat. Ces capacités permettent d’augmenter leur efficacité en sélectionnant les ressources les plus productives, en les planifiant à l’avance et, de manière plus avancée, en planifiant le parcours le plus court à travers ces différentes ressources durant la journée lorsque la pression sociale requière une meilleure précision dans le choix des ressources. Ces découvertes illustrent d’abord les capacités extraordinaires des chimpanzés, et deuxièmement que les aspects cognitifs peuvent être expliqués dans le milieu naturel des animaux. / Whereas numerous studies demonstrated fascinating behaviour of animals in their natural habitat, some important areas of research were difficult to tackle in the field. This is the case of many studies on cognitive aspects that required controlled environment to dissociate ecological and social influence from cognition. One of these important areas of research is the spatial cognition including spatial memory, spatial orientation mechanisms and the practical use of these abilities to travel efficiently, such as planning skills. This study on spatial cognition in wild chimpanzees took place in Taï National Park, a tropical dense forest where potential food resources are highly abundant in their 25 km² territory, and the visibility is approximately 30 meters. Adding to this complexity, chimpanzees live in a fission-fusion society, maintaining relationships with each other. Nevertheless, with a precise recording of chimpanzee’s location and activities and a precise botanic map of the territory, we were able to dissociate the ecological, social and cognitive effects and understand some relationships between these factors. Here, we showed that wild chimpanzees developed a precise mechanism to navigate efficiently in their large area using a Euclidean map containing accurate information about direction and distance to the known resources. This mechanism is highly adapted and efficient as the chimpanzees have a precise knowledge of the resources location in their area, remembering the location of thousand trees location. These highly developed abilities allowed them to increase their efficiency by selecting the most productive resources, planning them in advanced and on a higher level to plan the shortest path through these major resources during the day when the social pressure induce a higher precision in resource selection. These findings highlight first the outstanding spatial abilities of wild chimpanzees and second that cognition can be better explained in animals’ natural complex environment. / Trotz zahlreicher Studien, die das faszinierende Verhalten von Wildtieren in ihrer natürlichen Umwelt dokumentieren, bleiben einige Studienfelder schwer erfassbar. So ist zum Beispiel bei der Erforschung von bestimmten kognitiven Aspekten die Rücksichtnahme auf den Umweltfaktor erforderlich, damit Umwelt- und Sozialeinfluss von den kognitiven Faktoren unterschieden werden können. Zu diesen Untersuchungsfeldern gehört die Raumkognition, welche das Raumgedächtnis, die Mechanismen der Raumorientierung sowie deren effizientes Nutzen durch die Schimpansen, z.B. durch ihre Fähigkeit zum Planen, einschließt. Die vorgestellte Studie über Raumkognition bei wild lebenden Schimpansen wurde im Nationalpark von Tai durchgeführt, das heißt, in einem dichten tropischen Wald, wo potentielle Ressourcen bei einer Sichtweite von ungefähr 30 Metern auf einem 25 qm großen Areal reichlich verteilt sind. Hinzu kommt, dass Schimpansen in einer Fission-Fusion Gesellschaftsstruktur leben, die vielfache soziale Beziehungen fördern. Jedoch, mit einer genauen Registrierung der räumlichen Lage und der Aktivitäten der Schimpansen und anhand einer präzisen botanischen Karte des Gebiets, konnten wir die Umwelt-, Sozial- und kognitiven Effekte gegeneinander abgrenzen und somit die zwischen diesen unterschiedlichen Faktoren bestehenden Beziehungen erfassen. In dieser Studie zeigen wir, dass Schimpansen einen besonderen Mechanismus zur Raumorientierung auf ihrem Gebiet entwickelt haben. Dabei verfügen sie über eine euklidische Mind-Karte mit präzisen Informationen über Richtungen und Entfernungen zu den bekannten Ressourcen. Durch ein genaues Wissen über die Verteilung der Nahrungsressourcen auf ihrem Gebiet ist dieser Mechanismus hoch effizient. Dank dieser Fähigkeiten werden Schimpansen immer effizienter, indem sie die ergiebigsten Ressourcen auswählen, dabei planende Fähigkeiten einsetzen und weiterhin indem sie an einem Tag die kürzeste Strecke zu den verschiedenen Ressourcen ausmachen, wenn der soziale Druck höchste Präzision in der Wahl der Nahrungsressourcen erfordert. Diese Erkenntnisse erhellen zuallererst die außergewöhnlichen Fähigkeiten der wild lebenden Schimpansen und beweisen, dass sich kognitive Mechanismen bei wild lebenden Tieren in ihrer natürlichen Umwelt besser erklären lassen.

The purpose of this study is to examine the influence of visitors on six species of captive primates in Shou Shan Zoo. In this article, I compared the behavior and the use of enclosure of primates with or without audiences, and I studied the correlations among the visitors¡¦ behavior, the behavior of primates, and the use of enclosure of them. Data were collected from September 2006 to March 2007 (between 09:00 to 16:00 hrs). The Shou Shan Zoo¡¦s visitors were estimated as 681 (¡Ó 323.71) individuals in non-holidays and 2824 (¡Ó 810.15) individuals in holidays. The average feeding provided by visitors was 3.65 % for 6 primate species, and this was more than four times of the feeding rate in Taipei Zoo. This phenomenon will threat the welfare and health of animals. Although resting was the most frequent behavior of these six species of primates, the proportion of abnormal behavior in Chimpanzee display site where attracted highest number of audiences and the highest proportion of animal feeding performed by visitors was relatively high. The major behavior of captive Chimpanzees were rest (53.28%), abnormal (13.75%) and food-related behavior (12.93%), and the frequency of Chimpanzees used the edge zone beyond 70%. The major behavior of Borneo Orangutan was rest (64.10%), followed by food-related behavior (20.13%) and self-directed behavior (12.18%). The frequency of Borneo Orangutan in the enclosure was highest in the back zone. The major behavior of Hamadryas Baboons was rest (49.27%), followed by affiliative (21.10%) and food-related behavior (12.68%). The frequency of Hamadryas Baboon in the enclosure was 50.27% in the other and 47.35% in the back zone. The major behavior of Celebes was rest (55.12%), followed by affiliative behavior (13.10%) and active (12.91%). The frequency of Celebes in the enclosure was highest in the back zone (41.51%), followed by the enrich (31.50%) and the edge zone (23.50%). The major behavior of the Dark-handed gibbon was rest (54.40%), active (27.10%) and food-related behavior (12.17%), and the frequency of the Dark-handed gibbon in the enclosure was 54.40% in the enrich zoon, 27.00% in the edge zoon and 10.90% in the other zoon. The major behavior of the White-handed gibbon was rest (74.28%) and active (18.07%), and the frequency of it in the enclosure was 45.58% in the enrich zoon and 39.52% in the edge zoon. The frequency of the Chimpanzees¡¦ abnormal, undesirable and self-directed behavior were influenced by audiences, and the duration of abnormal and undesirable behavior were positively correlated with the visitors¡¦ active and feeding behavior, but that were negatively correlated with the visitors¡¦ behavior (ignore and look). The duration of the Borneo Orangutan¡¦s rest, active, food-related and self-directed behavior were influenced by audiences, and the duration of the Borneo Orangutan used the back and the enrich zone were significantly correlated with the visitors¡¦ behavior (active and look). The Hamadryas Baboon¡¦s rest (time) and undesirable behavior (frequency) were influenced by audiences, and the duration of rest, food-related and undesirable behavior were significantly correlated with the visitors¡¦ behavior (active, look, feeding and ignore), and the duration of the Hamadryas Baboon used the edge and the back zone were significantly correlated with the visitors¡¦ behavior (look and feeding). The frequency of the Celebes¡¦ self-directed and agonistic behavior were influenced by audiences, and the duration of active, self-directed, food-related and affiliative behavior were significantly correlated with the visitors¡¦ feeding behavior. The duration of the Dark-handed gibbons¡¦ active and food-related behavior and the frequency of the Dark-handed gibbons¡¦ agonistic behavior were influenced by audiences, and the duration of rest, active, food-related, self-directed, undesirable and agonistic behavior were significantly correlated with the visitors¡¦ behavior (active, look, feeding and ignore). The duration of Dark-handed gibbons used the edge, the back and the enrich zoon were influenced by audiences, and the duration of the Dark-handed gibbons used these three zones were significantly correlated with the visitors¡¦ behavior (active, feeding and ignore). The frequency of the White-handed gibbon¡¦s self-directed behavior was influenced by audiences, and the duration of active, food-related, undesirable and abnormal behavior were significantly correlated with the visitors¡¦ behavior (active, look, feeding and ignore). The duration of the White-handed gibbon used the other zoon was positively correlated with the visitors¡¦ behavior (active).

The goal of this study was to examine several aspects of the population genetics and population biology of the Nigeria-Cameroon chimpanzee at seven sampling locations in the south of Taraba State, Nigeria. Three of the sampling locations are within GGNP and two are situated just outside the southern boundary of GGNP. The final two sampling locations are found within Ngel Nyaki forest reserve, at each of the two forest fragments inside the reserve. Ngel Nyaki forest reserve was the focus of the study and the principal goal was to 16 determine if the community of chimpanzees at Ngel Nyaki forest reserve has become isolated from the chimpanzees at GGNP using microsatellite loci extracted from non-invasive sources of DNA. In Chapter two, the methods used to extract and amplify the DNA and the protocols used to confirm the genotypes are outlined. Chapter three examines the population structure of the chimpanzees among the regions sampled in this study, particularly addressing the question as to whether the chimpanzees at Ngel Nyaki forest reserve are isolated from the chimpanzees at GGNP. Chapter four investigates patterns of sex biased dispersal in the Nigeria-Cameroon chimpanzee. In Chapter five, population viability analysis is used to determine the fate of the chimpanzees at Ngel Nyaki forest reserve under a range of management scenarios. Chapter six summarizes the conclusions of the study and presents a conservation strategy to ensure the viability of the population of chimpanzees at Ngel Nyaki forest reserve.

Title from second page of PDF document. Includes bibliographical references (p. 145-173).

Les canaux semi-circulaires présentent un grand intérêt dans l'évolution. Des travaux récents ont montré que pour certains caractères, le génome humain est plus étroitement lié à celui du bonobo ou du chimpanzé que ces derniers entre eux. Dans ce contexte, il est important de comprendre le degré auquel les différences morphologiques et structurales entre ces trois espèces, reflètent les connaissances phylogéniques actuelles. Cette étude vise à comparer la variabilité anatomique des canaux semi-circulaires à partir de 260 examens tomodensitométriques d'homo sapiens, pan paniscus et pan troglodytes existants. Nous appliquons un modèle mathématique valide avec des examens micro tomodensitométriques et une quantification de l'erreur de mesure. Principalement, nous trouvons que les humains et les bonobos partagent plus de similarités entre eux qu'avec les chimpanzés par rapport a l'orientation tridimensionnelle de leurs canaux semi-circulaires, un résultat qui ne cadre pas avec les connaissances phylogénétiques actuelles. Une première hypothèse consiste en une évolution convergente dans laquelle les bonobos et les humains produisent indépendamment, des phénotypes semblables, peut-être en réponse aux pressions de sélection similaires éventuellement associées à des adaptations posturales. Une deuxième explication possible et plus parcimonieuse, c'est que la morphologie labyrinthique partagée entre le bonobo et l'homme représente la condition ancestrale à partir de laquelle les chimpanzés se sont déviés par la suite. La symétrie remarquable des CSC est le deuxième résultat majeur de cette étude pour ses implications dans la taphonomie. Il a le potentiel pour enquêter sur les fossiles altérés, déduire la probabilité de déformation post-mortem qui peut conduire à des difficultés dans la compréhension de la variation taxonomique, des relations phylogénétiques et de la morphologie fonctionnelle. / For some traits, the human genome is more closely related to either the bonobo or the chimpanzee genome than these are to each other. Therefore, it becomes crucial to understand whether morphological differences between humans, chimpanzees and bonobos reflect the well known phylogeny. Here we investigate intra and extra labyrinthine semicircular canals morphology using 260 computed tomography scans of homo sapiens, pan paniscus and pan troglodytes. We apply a mathematical model validated with micro-computed tomography scans and measurement error quantification. We find striking differences between, on the one hand, humans and bonobos and, on the other hand, chimpanzees concerning the 3D orientation of their semicircular canals. This finding does not fit with the phylogenetic knowledge. The first hypothesis is convergent evolution in which bonobos and humans produce independently similar phenotypes possibly in response to similar selection pressure maybe associated with postural adaptations. A second possible and more parsimonious explanation is that the bonobo-human labyrinthine shared morphology represents the ancestral condition with chimpanzees being subsequently derived. The remarkable symmetry of the SCC is the second major result of this study for its implications in taphonomy. It has the potential to investigate altered fossil, inferring the probability of post-mortem deformation which can lead to difficulties in understanding taxonomic variation, phylogenetic relationships, and functional morphology.