{"686350":{"#nid":"686350","#data":{"type":"event","title":"PhD Defense by Emma Bingham","body":[{"value":"\u003Cp\u003EIn partial fulfillment of the requirements for the degree of\u003C\/p\u003E\u003Cp\u003EDoctor of Philosophy in Quantitative Biosciences\u003Cbr\u003Ein the School of Physics\u003C\/p\u003E\u003Cp\u003EEmma Bingham\u003C\/p\u003E\u003Cp\u003EWill defend her dissertation\u003C\/p\u003E\u003Cp\u003EBiophysical scaffolding in the evolution of complexity\u003C\/p\u003E\u003Cp\u003EFriday November 21st, 2025\u003Cbr\u003EAt 9:00am EST\u003Cbr\u003EKrone Engineered Biosystems Building (EBB), CHOA Seminar Room 1005\u003C\/p\u003E\u003Cp\u003Ehttps:\/\/gatech.zoom.us\/j\/92410817040?pwd=cs5FG5mN4qidh9COKaka6LpIrBRM8k.1\u0026nbsp;\u003Cbr\u003EMeeting ID: 924 1081 7040\u003C\/p\u003E\u003Cp\u003EThesis Advisors:\u003Cbr\u003EPeter J. Yunker, Ph.D.\u003Cbr\u003ESchool of Physics\u003Cbr\u003EGeorgia Institute of Technology\u003C\/p\u003E\u003Cp\u003EWilliam C. Ratcliff, Ph.D.\u003Cbr\u003ESchool of Biological Sciences\u003Cbr\u003EGeorgia Institute of Technology\u003C\/p\u003E\u003Cp\u003ECommittee Members:\u003Cbr\u003ESaad Bhamla, Ph.D.\u003Cbr\u003ESchool of Chemical and Biomolecular Engineering\u003Cbr\u003EGeorgia Institute of Technology\u003C\/p\u003E\u003Cp\u003EJennifer Curtis, Ph.D.\u003Cbr\u003ESchool of Physics\u003Cbr\u003EGeorgia Institute of Technology\u003C\/p\u003E\u003Cp\u003EDaniel Weissman, Ph.D.\u003Cbr\u003EDept. of Physics\u003Cbr\u003EEmory University\u003Cbr\u003E\u0026nbsp;\u003Cbr\u003EABSTRACT: Pressure to become larger is thought to be a driver of the evolution of multicellular organisms. Large size can help an organism avoid predation, resist stress, use resources more efficiently, and more. However, though size can solve many problems, it also creates new ones, and it is not clear how nascent multicellular organisms overcome these problems, since they are simple clumps of cells that lack the group-level adaptations of established organisms.\u0026nbsp;\u003Cbr\u003EOne problem with large size involves nutrient limitation: nutrients usually cannot penetrate more than a few tens of microns at most into a group of cells, meaning that cells on the inside of a large group will be starved, and growth will be limited. However, our model organism for early multicellularity, snowflake yeast, defies these uptake limits. Over 1,000 days of selection for large size, these yeast evolved to grow exponentially to millimeter sizes, far larger than previously-demonstrated uptake limits. Snowflake yeast does not have cilia to move fluid around, nor does it have complex multicellular adaptations like a circulatory system. Instead, the organism\u0027s metabolism drives a rapid, long-range buoyant flow that enables nutrient-rich fluid to move throughout the cluster of cells.\u0026nbsp;\u003Cbr\u003EIn this thesis, I examine the phenomenon of metabolic flow and the organismal and environmental characteristics that make it possible. I argue that it is not merely unique to snowflake yeast clusters placed in perfectly still media with plentiful nutrients, but is possible across a wider range of environmental and organismal characteristics. I show that metabolically-driven flow remains effective in an environment with substantial external flows, widening the range of possible environments. I also examine the organismal characteristics that make flow possible for snowflake yeast, including permeability, toughness, and nutrient uptake rates. I suggest that emergent phenomena can circumvent the need for nascent multicellular organisms to evolve a morphologically complex body, including features like a circulatory system, in order to solve problems of large size. Instead, large size can evolve first, and the existing form and physics of the group can scaffold the subsequent evolution of development of the body plan.\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u003Cstrong\u003EBiophysical scaffolding in the evolution of complexity\u003C\/strong\u003E\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Biophysical scaffolding in the evolution of complexity"}],"uid":"27707","created_gmt":"2025-11-11 16:48:26","changed_gmt":"2025-11-11 16:49:09","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2025-11-21T09:00:00-05:00","event_time_end":"2025-11-21T11:00:00-05:00","event_time_end_last":"2025-11-21T11:00:00-05:00","gmt_time_start":"2025-11-21 14:00:00","gmt_time_end":"2025-11-21 16:00:00","gmt_time_end_last":"2025-11-21 16:00:00","rrule":null,"timezone":"America\/New_York"},"location":"Krone Engineered Biosystems Building (EBB), CHOA Seminar Room 1005","extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}