{"688832":{"#nid":"688832","#data":{"type":"event","title":"The School of Biological Sciences Spring 2026 Seminar Series presents Chris Martin","body":[{"value":"\u003Cp dir=\u0022ltr\u0022\u003E\u003Cstrong\u003EUnderstanding the mechanisms of speciation and adaptation is a fundamental question in biology that also provides an opportunity to uncover new gene functions of clinical relevance. Highly conserved genetic regulatory pathways shared across diverse vertebrate species have been shaped by adaptive evolution to produce spectacular morphological, behavioral, and ecological diversity. Here I review a decade of my lab\u2019s work investigating the rapid evolutionary transition from generalist algae-eating pupfishes to trophic specialists endemic to hypersaline lakes of San Salvador Island in the Bahamas and Laguna Chichancanab, Mexico. We show that colonizing these niches occurred in stages, beginning with selection on standing genetic variation for feeding behavior, then aided by adaptive introgression from diverse sources, and ending with selection on de novo mutations in key craniofacial genes. We discovered that only 157 single-nucleotide polymorphisms (SNPs) and 87 deletions are fixed between scale-eating and molluscivore specialists despite extensive phenotypic divergence in their craniofacial morphology, metabolism, and behavior. These few differences resulted in major transitions in ecological niches and the colonization of new fitness peaks and novel performance optima for scale-biting. Overall, our work provides a new microevolutionary framework for investigating how major ecological transitions occur in nature and illustrates how both shared and unique genetic variation contributes to diversification and provides a path through complex fitness landscapes for access to novel ecological niches.\u003C\/strong\u003E\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp dir=\u0022ltr\u0022\u003E\u003Cstrong\u003EThe origins and stages of adaptive radiation in Caribbean pupfishes: from genotype to fitness landscape\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"The origins and stages of adaptive radiation in Caribbean pupfishes: from genotype to fitness landscape"}],"uid":"36506","created_gmt":"2026-03-10 17:28:02","changed_gmt":"2026-03-10 18:02:32","author":"rbailey74","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2026-04-02T11:00:00-04:00","event_time_end":"2026-04-02T12:00:00-04:00","event_time_end_last":"2026-04-02T12:00:00-04:00","gmt_time_start":"2026-04-02 15:00:00","gmt_time_end":"2026-04-02 16:00:00","gmt_time_end_last":"2026-04-02 16:00:00","rrule":null,"timezone":"America\/New_York"},"location":"EBB 1005","extras":["free_food"],"hg_media":{"679564":{"id":"679564","type":"image","title":"chris_martin.jpg","body":null,"created":"1773163768","gmt_created":"2026-03-10 17:29:28","changed":"1773163768","gmt_changed":"2026-03-10 17:29:28","alt":"Photo of Chris Martin","file":{"fid":"263740","name":"chris_martin.jpg","image_path":"\/sites\/default\/files\/2026\/03\/10\/chris_martin.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/2026\/03\/10\/chris_martin.jpg","mime":"image\/jpeg","size":32281,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/2026\/03\/10\/chris_martin.jpg?itok=547z7Vn9"}}},"media_ids":["679564"],"groups":[{"id":"1275","name":"School of Biological Sciences"}],"categories":[],"keywords":[{"id":"172458","name":"biological sciences"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"177814","name":"Postdoc"},{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp dir=\u0022ltr\u0022\u003E\u003Ca href=\u0022mailto:rbailey74@gatech.edu\u0022\u003E\u003Cstrong\u003Erbailey74@gatech.edu\u003C\/strong\u003E\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}