Dissertation presented for the degree of Master of Science in the University of the Witwatersrand. / WHSLYP2017

Afin de limiter l’impact négatif des ravageurs sur les plantes cultivées, des agents de lutte biologique sont souvent introduits sous abris. Or, des interactions peuvent apparaître entre eux, comme la prédation intraguilde, et modifier l’efficacité de la lutte biologique. De plus, les défenses directes des plantes hôtes peuvent perturber l’efficacité des ennemis naturels. La question se pose donc de savoir s’il est possible de limiter les interactions négatives entre ennemis naturels et l’impact de la plante hôte sur leur développement. Pour répondre à cet objectif, afin d’optimiser la lutte biologique contre l’acarien Tetranychus urticae, ravageur très problématique, nous avons considéré deux cultivars de tomates caractérisés par des densités en trichomes et des concentrations en composés secondaires contrastéesl’acarien prédateur Phytoseiulus macropilis et Macrolophus pygmaeus, punaise prédatrice souvent employée pour lutter contre les aleurodes. Au cours d’essais conduits en serre, P. macropilis a permis de réguler T. urticae sans différence entre les deux cultivars, alors qu’en microcosmes le taux d’oviposition de P. macropilis a été supérieur sur le cultivar ayant la densité en trichomes non glandulaires la plus élevée. La consommation d’œufs de P. macropilis par M. pygmaeus en microcosmes n’a pas été observée en serre. Les interactions entre arthropodes se sont également traduites par une agrégation supérieure des T. urticae en présence des deux prédateurs et de P. macropilis en présence de M. pygmaeus. Avant de proposer P. macropilis comme nouvel agent de lutte bio / To suppress pest populations to such levels that damage to thecrop is minimized, multiple biological control agents are oftenintroduced in greenhouses. However, negative interactionsamong them, such as intraguild predation, might appear thatcan decrease the effi ciency of the plant protection strategy.Furthermore, plant direct (physical or chemical) defenseshave a negative impact on the pests but might also have animpact on the natural enemies. Therefore, the question iswhether it is possible to limit the negative interactions amongbiological control agents and the infl uence of the crop on thebehavior and development of the natural enemies. To optimizebiological control of Tetranychus urticae, a very problematicpest in tomato greenhouses, the effi ciency of the predatorymite Phytoseiulus macropilis was tested on two cultivars withdifferent trichome densities and concentrations of secondarycompounds, in presence or absence of Macrolophus pygmaeus,a mirid often used to regulate whitefl y populations.During two years, under greenhouse conditions, P. macropiliswell-controlled the population of T. urticae. There was no evidenceof intraguild predation between the two predators, butin the presence of M. pygmaeus, P. macropilis tended to havea more clumped spatial distribution. However, in microcosms,M. pygmaeus fed on P. macropilis eggs. Moreover, P. macropilislaid signifi cantly more eggs on the tomato cultivar with thehighest density of non-glandular trichomes, but this resultwas only observed in microcosms. The different dynami

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).

付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20964号 / 理博第4416号 / 新制||理||1634(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 Michael Alan Huffman, 准教授 足立 幾磨, 教授 友永 雅己 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Due to an extreme asymmetry in parental investment, raising the potential for sexual conflict, orangutans provide unique insights into the role of sexual conflict in male and female reproductive strategies. Sexual selection acts on reproductive strategies, selecting for strategies that increase an individual's reproductive success. Sexual conflict results when the reproductive strategies of one sex impose costs on the other. Three forms of sexual selection have been documented in orangutans—male-male competition, female choice, and sexual coercion. This dissertation asks (1) how males employ reproductive strategies to increase their likelihood of reproductive success in the face of multi-male mating by females and (2) how females employ reproductive strategies to enact female choice and increase infant survival in the face of male-male competition and sexual coercion. I investigate these two questions using genetic paternity, long-term association data, and a year of behavioral data from orangutans (Pongo pygmaeus wurmbii) in Gunung Palung National Park, West Kalimantan, Indonesia. Brown-modified Hinde Indices, initiation and termination of associations, and following data reveal that female participation is necessary to sustain longer male-female associations and females use facultative associations to employ mate choice. Genetic paternity determination found low reproductive skew, with flanged males siring more offspring than unflanged males. Investigation of female infanticide avoidance strategies showed that females with dependent offspring under age six associate with males less often than other categories of females do, and mothers decrease the distance with their offspring during associations with males. These results highlight the importance of both female choice and male-male competition in reproductive outcomes, and illustrate how facultative associations play a key role in the reproductive strategies of both male and female orangutans. Both sexes’ strategies are studied, demonstrating the dynamic co-evolution of strategies and counterstrategies. I also consider the implications of these findings for the evolution of male bimaturism. Examining orangutan mating and reproductive behaviors deepens our understanding of how sexual conflict and sexual selection have shaped their unusual mating system and broadens our understanding of sexual conflict in reproductive strategies in a species with an extreme disparity between maternal and paternal investment. / 2025-08-31T00:00:00Z

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Adipositas ist eine polymorphe chronische Erkrankung mit epidemischer Prävalenz. Im katabolen Leptin-Melanocortin-Signalweg ist das Proopiomelanocortin Gen (POMC) ein zentrales Element, das bei Dysfunktion massive Adipositas bewirken kann. Auch eine kürzlich identifizierte intragenische Methylierungsvariante des POMC wurde mit Adipositas assoziiert und deutet somit auf eine mögliche epigenetische Modulation des Gewichtsphänotyps hin. Zur Aufklärung der Relevanz, Stabilität und Entwicklung dieser epigenetischen Modifikation wurden die Funktionalität, Ontogenese und Phylogenese der POMC DNA-Methylierung untersucht. In vitro Analysen zeigten DNA-Methylierungsabhängige Promoteraktivität beider CpG-Inseln (CGIs) des POMC. Diese hier erstmals beschriebene Transkriptionsaktivität der intragenischen CGI weist auf einen alternativen Promoter des POMC hin. Hinsichtlich der Ontogenese konnten in Mensch und Maus postnatal stabile DNA-Methylierungsmuster mit interindividueller Konservierung für beide CGIs des POMC identifiziert werden. Zusätzlich erwiesen sich Gewebeunabhängigkeit der DNA-Methylierungsmuster und ihre pränatale Ausbildung zwischen dem Blastocystenstadium und der frühen Organogenese in der Maus. Die POMC DNA-Methylierungsmuster upstream des Exon3 unterscheiden sich in Mensch und Maus. Der mögliche Einfluss von primatenspezifischen Alu-Elementen im Intron2 des POMC hierauf wurde in verschiedenen Primatenfamilien analysiert. Die Ergebnisse zeigen eine bedingte Assoziation der Alu-Elemente mit der DNA-Methylierung in der entsprechenden Region, lassen jedoch auch weitere Einflussfaktoren vermuten. Insgesamt zeigt diese Arbeit, dass die POMC DNA-Methylierung artspezifisch konserviert ist und in der frühen Embryogenese, vermutlich Alu-abhängig, ausgebildet wird. Dabei könnten stochastische Variationen der DNA-Methylierung die POMC-Aktivität beeinflussen und somit das Risiko für Adipositas erhöhen. / Obesity is a polymorphic chronic disease with epidemic prevalence. Within the catabolic leptin-melanocortin signaling pathway pre-proopiomelanocortin (POMC) is a pivotal element. Dysfunction of POMC, e.g. due to mutations, can cause severe obesity. Moreover, a recently identified intragenic methylation variant of POMC was found to be associated with obesity. Therefore, this indicates potential epigenetic modulation of the weight phenotype. To gain further insight into the relevance, stability, and origin of this epigenetic modification, the functionality, ontogenesis, and phylogenesis of the POMC DNA methylation patterns were analyzed. In vitro analyses revealed DNA methylation-dependent promoter activity of both CpG islands (CGIs) of POMC. Thereby, the intragenic CGI was identified as a potential alternative promoter of POMC, which has not been described before. Regarding the ontogenesis, postnatally stable POMC DNA methylation patterns with interindividual conservation were detected for both CGIs in humans and mice. In addition, it was observed that the POMC DNA methylation patterns are non-tissue-specific, stable upon long time administration of a high fat diet, and develop prenatally between the blastocystal stage and the early organogenesis. The POMC DNA methylation pattern upstream of exon3 differs in humans and mice. A possible influence of primate-specific Alu elements within the intron2 region of POMC was analyzed in various primate families. Results evince a partial association of the Alu elements with the DNA methylation pattern in this particular region, but also suggest an influence of additional factors. Overall, this work demonstrates that DNA methylation of the POMC locus is species-specific highly conserved, and that it is established during early embryogenesis, possibly Alu-triggered. In the course of this, stochastic variances of the POMC DNA methylation might influence the POMC activity and consequently alter the risk to develop obesity.