000K utf8 1100 $c2025 1500 eng 2050 urn:nbn:de:gbv:8:3-2025-00012-2 3000 Stenvers, Vanessa Isabel 4000 Midwater invertebrates in the deep pelagic ocean$dAdaptations, interactions and impacts of stressors$hChristian-Albrechts-Universität zu Kiel [Stenvers, Vanessa Isabel] 4030 Kiel$nChristian-Albrechts-Universität zu Kiel 4209 The midwater, or deep open ocean, forms over 90% of the livable space on Earth and houses one of the largest animal communities alive. As such, midwater ecosystems form important links in oceanic food webs and play a crucial role in the regulation of our climate by keeping atmospheric carbon at depth. Yet despite their importance on a global scale, midwater ecosystems remain largely unexplored. My PhD thesis aims to investigate adaptations in midwater invertebrates, including their associations, evolution and responses to human-induced stressors. The focus was on gelatinous organisms and hyperiid amphipods, as both are highly abundant in the midwater and frequently interact. In my first chapter, I investigated the impacts of global warming and deep-sea mining induced sediment plumes on a midwater jellyfish, combining insights gained from physiology, gene expression and changes in associated microbiota. For my second chapter, I studied the interactions of hyperiid amphipods with gelatinous organisms to show how symbiotic behavior drives morphological adaptations in camouflage and eye complexity, using nearly 30 years of remotely operated vehicle observations. For my third chapter, I investigated the compound eyes in a family of closely related hyperiid amphipods (Oxycephalidae) using micro-computed tomography (micro-CT) to map their optics and model their vision. Here, I was able to show how fine-scale visual adaptations can elucidate visual ecology and provide insights into the evolutionary drivers of vision in midwater amphipods. All in all, my PhD emphasizes the importance of combining multiple methods to gain detailed insights into life in the largest, but least studied habitat on Earth. 4950 https://nbn-resolving.org/urn:nbn:de:gbv:8:3-2025-00012-2$xR$3Volltext$534 4961 https://macau.uni-kiel.de/receive/macau_mods_00005532 5051 570 5550 Deep Sea 5550 Evolution 5550 Midwater 5550 Transcriptomics 5550 Visual ecology