{ "148235-21903427": { "datetime_modified":"20260512T113906", "datetime_start":"20260515T100000", "datetime_end":"20260515T110000", "has_end_time":1, "date_start":"2026-05-15", "date_end":"2026-05-15", "time_start":"10:00:00", "time_end":"11:00:00", "time_zone":"America\/Detroit", "event_title":"EEB Student Thesis Defense - Comparing Phyllostomid Bat Brains to Feeding Strategies", "occurrence_title":"", "combined_title":"EEB Student Thesis Defense - Comparing Phyllostomid Bat Brains to Feeding Strategies: Samantha Henry", "event_subtitle":"Samantha Henry", "event_type":"Workshop \/ Seminar", "event_type_id":"21", "description":"Summary: In mammals, large brains are associated with improved cognitive performance and complex social interactions. Some hypotheses posit that solving complex ecological problems (e.g., foraging) drive some taxa to evolve large brains. Although many studies have analyzed bat brain size relative to diet, few have analyzed bat brain shape in the same way. The bat family Phyllostomidae is an ideal taxonomic group to examine brain morphology and diet because of the wide range of diet types within the family, including carnivores, frugivores, insectivores, nectarivores, omnivores, and sanguivores. My thesis addressed two questions: (1) what is the effect of various diets on brain size in phyllostomid bats; and (2) what is the effect of various diets on the shape of the brain in phyllostomid bats? Using 3D Slicer (3D segmentation and visualization software), I generated endocranial casts (endocasts) from the skulls of 73 voucher specimens located in four natural history museums. Endocasts are often used as a proxy for brain size and shape. I used 3D Slicer to determine the endocast volume, measure the occipital condyle width (a proxy for body size), place 30 fixed landmarks on the endocast, and export Procrustes landmark coordinates to determine size and shape. The results indicated that diet was not a significant predictor of endocast volume in phylogenetic analysis of variance (ANOVA) models. However, the generalized linear mixed models showed that frugivorous and sanguivorous phyllostomids had significantly larger endocast volumes than insectivorous phyllostomids, but the magnitude of the change was not large. Regarding endocast shape, the principal component analysis (PCA) showed that the first principal component accounts for 18.9% of the variation in brain shape, which corresponds with some aspects of cerebrum and cerebellum size along the sagittal plane, and length of the olfactory bulb. The second principal component accounts for 14.3% of the variation in brain shape, which corresponds with changes in endocast height and width. The third principal component accounts for 10.6% of the variation in brain shape, which corresponds to the width of the olfactory bulb and the paraflocculus. Based on the PCA and the phylogenetic Procrustes ANOVA results, the effects of diet on endocast shape in phyllostomid bats appear minimal or absent. Instead, endocast (and likely brain) shape seems to be driven primarily by other, potentially species-specific factors that vary among species.", "occurrence_notes":null, "guid":"148235-21903427@events.umich.edu", "permalink":"http:\/\/events.umich.edu\/event\/148235", "building_id":"1005169", "building_name":"Biological Sciences Building", "campus_maps_id":"631", "room":"1010", "location_name":"Biological Sciences Building", "has_livestream":0, "cost":"", "tags":["Bsbsigns","department of ecology and evolutionary biology","Ecology & Biology","Ecology And Evolutionary Biology","eeb","Graduate School","Graduate Students","Thesis Defense","biological science"], "website":"", "sponsors":[ { "group_name":"EEB Defenses", "group_id":"3821", "website":"" } ], "image_url":"https:\/\/events.umich.edu\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "styled_images":{ "event_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_thumb\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_large":"https:\/\/events.umich.edu\/media\/cache\/event_large\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_large_2x":"https:\/\/events.umich.edu\/media\/cache\/event_large_2x\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/event_large_lightbox\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "group_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_thumb\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "group_thumb_square":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_thumb_square\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "group_large":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_large\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "group_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_large_lightbox\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_large_crop":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_large_crop\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_list":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_list\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_list_2x":"https:\/\/events.umich.edu\/media\/cache\/event_list_2x\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_grid":"https:\/\/events.umich.edu\/media\/cache\/event_grid\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_grid_2x":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_grid_2x\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_feature_large":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_feature_large\/media\/attachments\/2026\/05\/event_148235_original-1.jpg", "event_feature_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_feature_thumb\/media\/attachments\/2026\/05\/event_148235_original-1.jpg" }, "occurrence_count":1, "first_occurrence":21903427 } , "148237-21903428": { "datetime_modified":"20260512T115037", "datetime_start":"20260522T100000", "datetime_end":"20260522T110000", "has_end_time":1, "date_start":"2026-05-22", "date_end":"2026-05-22", "time_start":"10:00:00", "time_end":"11:00:00", "time_zone":"America\/Detroit", "event_title":"EEB Student Dissertation Defense - Defining the molecular mechanisms of migration in monarch butterfly", "occurrence_title":"", "combined_title":"EEB Student Dissertation Defense - Defining the molecular mechanisms of migration in monarch butterfly: Samuel Stratton", "event_subtitle":"Samuel Stratton", "event_type":"Workshop \/ Seminar", "event_type_id":"21", "description":"Summary: Each year during the fall a na\u00efve generation of monarch butterflies engages in a trans-continental migration, despite never having migrated before, which crosses over 4000km and spans 6-8 months. The fall migrant generation is in stark contrast to the preceding summer generation of butterflies who do not engage in such a feat but breed locally. Fall migration requires the coordinated expression of seasonally plastic traits such as oriented flight behavior and reproductive diapause (delayed reproduction during migration). The amalgamation of these component traits is dubbed the migratory syndrome. Yet, how these component phenotypes are integrated to form the migratory syndrome remains a largely open question. In my dissertation I studied how environmental and developmental factors interact to influence phenotypic plasticity of component migratory traits by combining field experiments with multi-omics (genomic, transcriptomic, and epigenomic) techniques. In Chapter 2 I uncover that reproductive diapause imparts a lasting transcriptional state which I hypothesize assists in the robustness of monarch butterflies during their return migration. In Chapter 3 I demonstrate that reproductive diapause and oriented flight are distinctly induced throughout the season, and each is regulated by tissue-specific transcriptional modules. Further, I also find that the unique oriented flight behavior during the seasonal transition from summer to fall is controlled by substantial cryptic genetic variation, which I hypothesize helps maintain behavioral diversity amidst seasonal unpredictability. Lastly, in Chapter 4 I present research which combines RNA- and ATAC-seq data to suggest that seasonal transcriptional plasticity is controlled by unique sets of seasonally regulated transcription factors. Overall, these works demonstrate the importance of environmental variation in defining the genetic architecture of the migratory syndrome and the regulatory mechanisms that control seasonal transcriptional plasticity. Defining these mechanisms helps us understand the evolution of migration as they define the substrates by which natural selection can operate.", "occurrence_notes":null, "guid":"148237-21903428@events.umich.edu", "permalink":"http:\/\/events.umich.edu\/event\/148237", "building_id":"1005169", "building_name":"Biological Sciences Building", "campus_maps_id":"631", "room":"1010", "location_name":"Biological Sciences Building", "has_livestream":0, "cost":"", "tags":["Graduate Students","Graduate School","eeb","Ecology And Evolutionary Biology","Ecology & Biology","Dissertation","department of ecology and evolutionary biology","Bsbsigns","biological science"], "website":"", "sponsors":[ { "group_name":"EEB Defenses", "group_id":"3821", "website":"" } ], "image_url":"https:\/\/events.umich.edu\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "styled_images":{ "event_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_thumb\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_large":"https:\/\/events.umich.edu\/media\/cache\/event_large\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_large_2x":"https:\/\/events.umich.edu\/media\/cache\/event_large_2x\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/event_large_lightbox\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "group_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_thumb\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "group_thumb_square":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_thumb_square\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "group_large":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_large\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "group_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_large_lightbox\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_large_crop":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_large_crop\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_list":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_list\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_list_2x":"https:\/\/events.umich.edu\/media\/cache\/event_list_2x\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_grid":"https:\/\/events.umich.edu\/media\/cache\/event_grid\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_grid_2x":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_grid_2x\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_feature_large":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_feature_large\/media\/attachments\/2026\/05\/event_148237_original-1.jpg", "event_feature_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_feature_thumb\/media\/attachments\/2026\/05\/event_148237_original-1.jpg" }, "occurrence_count":1, "first_occurrence":21903428 } }