Title Promoter Affiliations Abstract "Effects of habitat fragmentation on nectar composition in the butterfly pollinated orchid species Gymnadenia Conopsea." "Olivier Honnay" "Ecology, Evolution and Biodiversity Conservation" "Recent comprehensive meta-analyses have demonstrated that plant traits such as breeding system and seed bank persistence mediate the response of a species to anthropogenic habitat fragmentation. In turn, some evidence has recently become available that habitat fragmentation may also exert selective forces on the plant traits themselves. One such a trait is nectar chemical composition. Nectar plays a crucial role in the interactions between plants and their pollinators and hence in mating success and mating patterns. Because of the phenotypic variation in nectar composition, its inheritability, and the direct link between nectar production and plant reproductive success, it can be expected that nectar characteristics are subject to strong selective forces. In small and isolated populations, individuals with high nectar production (or a specific chemical nectar composition) may have a strong selective advantage because they will be more attractive to the scarce insect pollinators. On the other hand, increased nectar production may increase geitonogamous pollination and cause inbreeding depression. Our general project objective is to test the hypothesis that habitat fragmentation may alter the nectar production and the nectar composition of a plant species through selection. Our study species is the rewarding moth and butterfly pollinated orchid Gymnadenia conopsea which typically occurs in highly fragmented calcareous grasslands. Specific attention will be paid to the Amino Acid composition of the nectar, as it is expected that AA composition is highly important for butterfly-pollinated species in nitrogen poor environments. More specific, we aim at quantifying variability in nectar characteristics in G. conopsea, in relation to the degree of habitat fragmentation, fruit set, degree of selfing and insect visitation rates" "Managing plant species translocations: using genomic tools to unraveling interactions between adaptation to climate and adaptation to habitat fragmentation" "Olivier Honnay" "Ecology, Evolution and Biodiversity Conservation" "Global warming is occurring to a rate that exceeds the potential of most species to evolve phenotypes adapted to warmer climates. Assisted migration, or the deliberate northward translocation of individuals, is a widely discussed conservation strategy aiming to introduce phenotypes pre-adapted to projected climate change. However, there is a critical lack of assisted migration studies integrating the effects of habitat fragmentation, another major global change stressor that threatens the persistence and adaptive potential of species and ecosystems across their entire distributions. Theory predicts that adaptation to ongoing habitat fragmentation can conflict with climate change evolution and assisted migration efforts. We propose a unique assisted migration framework integrating the combined effects of climate change and habitat fragmentation, to deliver the first empirical test of various assisted migration scenarios on the persistence and adaptive potential of a model plant species, Primula elatior, in a fragmented landscape. We compare extensive greenhouse and field experiments with complementary genomics approaches to evaluate the effectiveness of each method in the study and monitoring of assisted migration actions. The range of implications of this research vary from understanding the integrated ecoevolutionary impacts of two major ongoing global change stressors, to accounting for the evolutionary consequences of assisted migration strategies." "Can cooperative breeding buffer the impacts of habitat fragmentation?" "Luc Lens" Biology "In cooperative breeding species some individuals forego to breed independently and help raising offspring that are not their own. Whether and how facultative cooperative breeders may adaptively respond to population fragmentation remains poorly understood. We will investigate this question in an afro-tropical bird, Phyllastrephus placidus, in three different fragmented forest archipelagos located within the Eastern Arc Mountains biodiversity hotspot." "Effects of Afrotropical rainforest fragmentation on life-history strategies in a cooperative breeding bird." "Luc Lens" Biology "We will study how territory quality, habitat fragmentation and isolation shape reproductive, dispersal, settlement, and territorial strategies in fragmented populations of a tropical, cooperative breeder. Hypotheses will be tested by non-invasive measures and samples, field experiments, behavioral observations and a population model that tests how environmental quality and cooperation drive the joint evolution of sex-specific dispersal distance and timing." "Effects of Afrotropical rainforest fragmentation on lifehistory strategies in a cooperative breeding bird." "Erik Matthysen" "Evolutionary ecology group (EVECO)" "We will study how the combination of territory quality, habitat fragmentation and isolation shape reproductive, dispersal, settlement, and territorial strategies in fragmented populations of a tropical, cooperative breeding bird species." "Plant-pollinator and plant-soil interactions in houndstongue: biotic selection mosaics in a plant species from spatially structured dune habitat?" "Dries Bonte" Biology "Habitat patches in fragmented landscapes are expected to harbor distinct pollinator and herbivore communities according to patch configuration and local environmental factors. Consequently, plant populations in fragmented landscapes are expected to experience distinct selection pressures exerted by local pollinators and herbivores. The goal of this study is to examine these selection pressures and their feedback with plant population genetic structure." "Year-round sociality under anthropogenic change in a cooperatively breeding bird" "Luc Lens" Biology "Global change challenges biodiversity worldwide, and the ability of species to respond to rapid environmental shifts is of major concern in current biology. Yet, it remains poorly understood how effects of anthropogenic change, such as large-scale habitat fragmentation and climate change, impact sociality in animals. So far, an overwhelming majority of studies focused on the breeding season, while the non-breeding season is believed to represent the most critical period in balancing costs and benefits of sociality year-round. In this project, I aim to predict how anthropogenic change shapes broad patterns of sociality based on a fine-grained understanding of the drivers underlying year-round sociality. As model system, I will study a cooperatively-breeding songbird (placid greenbul, Phyllastrephus placidus) inhabiting the fragmented cloud forest archipelago of the Eastern Arc Mountains biodiversity hotspot. Building on a unique long-term dataset, this project will combine state-of-the-art high-resolution animal tracking, statistical and predictive modelling, and a region-wide survey to address the following objectives: (i) to model large-scale habitat suitability in relation to habitat fragmentation and climatic conditions, (ii) to assess the role of spatio-temporal variation in habitat suitability in shaping sociality year-round, and (iii) to predict large-scale patterns of sociality under anthropogenic change." "Monitoring and predicting snail-borne diseases: a multidisciplinary approach" "Filip Volckaert" "Ecology, Evolution and Biodiversity Conservation" "Human activities have become the principal drivers of global change, encompassing habitat destruction and fragmentation, land use change, pollution, overexploitation, and climate change. These processes exert profound influences on terrestrial and aquatic ecosystems, with climate change, in particular, altering freshwater ecosystems through rising temperatures, increased evaporation, reduced oxygen levels, shifting precipitation patterns, and heightened occurrences of extreme events such as heatwaves and droughts. Such changes significantly impact the species inhabiting these aquatic environments, including disease vectors.Schistosomiasis, a tropical parasitic disease afflicting more than 200 million individuals worldwide, is transmitted through freshwater snails. However, the response of these snails to climate change and the influence on the transmission dynamics of the disease remain uncertain. Species can navigate climate change by adapting to changing environmental conditions or by dispersing to more suitable habitats. The extent to which each of these strategies applies to intermediate host snails of schistosomiasis remains uncertain. This PhD thesis investigates the local adaptation potential of the schistosome intermediate snail host, Bulinus truncatus, to temperature, and assesses how climate change will affect the distribution of this species.The thesis commences by conducting an extensive review of the literature on the ecology of African intermediate snail hosts of schistosomiasis. This systematic review identifies temperature and precipitation as key drivers of large-scale snail distributions, with water chemistry and waterbody characteristics determining snail distributions at a regional level. However, it also reveals a fragmented body of research spanning several decades, characterized by significant knowledge gaps and limited, often flawed, studies with small sample sizes, pseudoreplication, or insufficient replicates. As a result, the dataset is deemed unreliable for assessing the impact of climate change on these intermediate host snails.Given the pivotal role of temperature in shaping snail distributions, the thesis explores the effects of temperature on the life-history traits of B. truncatus. As the intermediate snail host with the broadest distribution, B. truncatus plays a crucial role in determining the maximum geographical extent of schistosomiasis, making it an ideal subject to explore the impact of climate change on the distribution of the disease. The findings reveal that B. truncatus demonstrates substantial local adaptation in terms of phenology, physiology, and genetic makeup. Adaptations of life-history traits are evident, with warm-origin snails characterised by reduced growth and survival rates at higher temperatures that are compensated by higher reproduction rates. In contrast, cold-origin snails exhibit higher growth rates, optimizing their performance in shorter growing seasons. Physiological adaptations include elevated sugar and haemoglobin content in cold-adapted snails, enhancing mobility at lower temperatures. Warm-adapted snails exhibit increased protein levels that might be attributed to increased levels of heat-shock proteins, protecting their proteins from denaturation under high temperatures, but they also show greater oxidative damage, which could limit their lifespan. Additionally, heightened phenoloxidase levels indicate a more robust immune response to parasites in snails from regions with higher parasite diversity. Moreover, an analysis of single nucleotide polymorphisms identifies 633 outlier markers associated with temperature or precipitation, putatively providing a genetic basis for these adaptations and underscoring the species' high potential to adapt to changing climate conditions.Subsequently, the thesis models the present and future distribution of B. truncatus by integrating both correlative and mechanistic species distribution models. While correlative models correlate species observations with environmental variables, mechanistic models incorporate explicit ecological knowledge to build process-explicit models. The combined approach predicts an up to 33 % increase in the area suitable habitat for B. truncatus by 2080-2100, predominantly in Central Africa and Southern Europe, while habitat suitability declines in the Sahel region. The current habitat suitability predictions closely align with areas of high schistosomiasis prevalence, suggesting that these models can be employed for schistosomiasis risk assessment. This implies a potential decrease in schistosomiasis risk in the Sahel, a highly endemic region, and an increase in risk in Southern Europe and Central Africa.While the results of this thesis do not directly enable local distribution forecasts, they serve to identify broader regions where schistosomiasis prevalence may change. Consequently, monitoring programs can be implemented to track potential snail or parasite invasions, and early control measures can be employed to mitigate the risk of new disease outbreaks. Furthermore, acquiring additional data on the ecology of intermediate hosts and developing microclimatic models for freshwater habitats can enhance regional-scale snail distribution models. Additionally, the high capacity for local adaptation of the snails suggests that they may adapt to other factors, such as parasitism, predation, or pesticides which could have implications for the emergence of schistosomiasis in new areas and the efficiency of snail control measures. Especially in regions where molluscicides are regularly applied or natural predators are present, high levels of local adaptation could potentially lead to molluscicide resistance or predator evasion behaviour.In conclusion, this thesis advances our understanding of the response of schistosome intermediate snail hosts to temperature and their potential for local adaptation. Additionally, it sheds light on how climate change may influence the distribution of these hosts and, consequently, the dynamics of schistosomiasis transmission." "Systematic conservation planning in the high Andes of Bolivia: application of modeling tools for integrative management of natural areas." "Evolutionary ecology group (EVECO)" "The main goal of this project is to evaluate and compare the performance and the constraints in the use of the two mostly used systematic conservation planning tools, Marxan and Zonation, in a tropical terrestrial setting. First, I will collect and process information on biodiversity, ecosystem services and socio-economy of the Tunari National Park of Bolivia. These data will then be used to model the potential suitability of the habitat under current and future predicted climatic scenarios. Finally, I will use Marxan and Zonation to generate a decisionsystem about conservation action for biodiversity and ecosystem services while taking into account anthropogenic and economical requirements, as well as habitat fragmentation and connectivity issues." "Systematic conservation planning in the high Andes of Bolivia: application of modeling tools for integrative management of natural areas." "Evolutionary ecology group (EVECO)" "The main goal of this project is to evaluate and compare the performance and the constraints in the use of the two mostly used systematic conservation planning tools, Marxan and Zonation, in a tropical terrestrial setting. First, I will collect and process information on biodiversity, ecosystem services and socio-economy of the Tunari National Park of Bolivia. These datawill then be used to model the potential suitability of the habitat under current and future predicted climatic scenarios. Finally, I will use Marxan and Zonation to generate a decisionsystem about conservation action for biodiversity and ecosystem services while taking into account anthropogenic and economical requirements, as well as habitat fragmentation andconnectivity issues."