Jack A. Gilbert

Principal Investigator

Professor Jack A. Gilbert (he/him) earned his Ph.D. from Unilever and Nottingham University, UK in 2002, and received his postdoctoral training at Queens University, Canada. From 2005-2010 he was a senior scientist at Plymouth Marine Laboratory, UK; and from 2010-2018 he was Group Leader for Microbial Ecology at Argonne National Laboratory, a Professor of Surgery, and Director of The Microbiome Center at University of Chicago. In 2019 he moved to the University of California San Diego, where he is a Professor in Pediatrics and Scripps Institution of Oceanography, Associate Vice Chancellor for Marine Science, and Director of both the Microbiome and Metagenomics Center and the Microbiome Core Facility. Dr. Gilbert uses molecular analysis to test fundamental hypotheses in microbial ecology. He cofounded the Earth Microbiome Project and American Gut Project. He has authored more than 450 peer reviewed publications and book chapters on microbial ecology. He is the founding Editor in Chief of mSystems journal. In 2014 he was recognized on Crain’s Business Chicago’s 40 Under 40 List, and in 2015 he was listed as one of the 50 most influential scientists by Business Insider, and in the Brilliant Ten by Popular Scientist. In 2016 he won the Altemeier Prize from the Surgical Infection Society, and the WH Pierce Prize from the Society for Applied Microbiology for research excellence. In 2017 he co-authored “Dirt is Good”, a popular science guide to the microbiome and children’s health. In 2018, he founded BiomeSense Inc. to produce automated microbiome sensors. In 2021 Dr Gilbert became the UCSD PI for the National Institutes of Health’s $175M Nutrition for Precision Health program. In 2023 he became President of Applied Microbiology International, and won the 2023 IFF Microbiome Science Prize. His publications can be found here.

Sarah M. Allard

Associate Project Scientist

Sarah (she/her) began her research career as an undergraduate, studying bees and pollination, and then moved on to an ORISE fellowship at the US Food and Drug Administration’s Center for Food Safety and Applied Nutrition, where she first became enamored with microbiology, conducting research focused on on-farm food safety and biological control of foodborne pathogens. Sarah received her PhD in Plant Science from the University of Maryland and remained at UMD for a postdoctoral fellowship in the Maryland Institute of Applied Environmental Health. There, she studied crop, soil, and water microbiomes in the context of food safety and environmental change. In her current role at UCSD, Sarah is exploring how microbiome research can be harnessed to support environmental restoration, safe and productive food systems, and the betterment of human health. Sarah is committed to helping students prepare a diverse skillset to enable effective interdisciplinary research and communication. She coordinates an interdisciplinary Research Experience and Mentoring program designed to build a robust mentoring environment and facilitate hands-on training for local undergraduate students interested in pursuing STEM careers. She is also the diversity coordinator for the Microbiome and Metagenomics Center at UCSD, part of NIH’s Nutrition for Precision Health program, and she is an editor at mSystems. More information can be found on her website, and her publications can be seen here.


Gertrude Ecklu-Mensah

Assistant Project Scientist

Gertrude (she/her) is always enthusiastic about biomedical research with strong translational focus and clinical applications. She has over 2 decades of combined academic and industry experience in conducting both laboratory and clinic-based studies. She holds a Ph.D. in Biochemistry with additional training in Molecular Biology and Immunology of Infectious Diseases from the University of Ghana and the University of Copenhagen. Currently, she is an Assistant Project Scientist with UC San Diego, where she conducts research at the intersection of nutrition, microbiome, metabolism, and chronic diseases, where she addresses fundamental questions on how diets working through the microbiome can be leveraged to improve gut, chronic and metabolic health with great precision. she has written and contributed to several high-impact publications and funded grant proposals. Her expertise spans project management, clinical research, scientific writing, immunology, molecular epidemiology, cell biology, bioinformatics, multi-omic analysis and data science. Her publications can be found here.



Megan S. Hill

Assistant Project Scientist

Megan (she/her, previously known as Megan Thoemmes) received her PhD in 2019 from the Applied Ecology department at North Carolina State University, under the direction of Dr Rob Dunn. Her work focuses on the microbes and arthropods found on and around mammal bodies, including those associated with humans, chimpanzees, and Key Largo woodrats. She is interested in how the built environment shapes species interactions and what factors drive differences among mammal structures, as well as how those differences affect individual health and well-being.

In the Gilbert lab, Megan primarily studies microbial selection on the International Space Station and the use of novel intervention methods to reduce antibiotic resistance and virulence in pathogens at Rady Children’s Hospital.  Previous work includes the development of the Meet Your Mites project and work on the Wild Life of Our Homes project. Her publications can be found here.

Postdoctoral Scholars

Mariah Coley

Postdoctoral Scholar

Mariah (she/her) is a biogeographer with a wide range of training and research experience spanning microbial ecology, soil sciences, environmental health, and international development in Africa. She earned her PhD in Geography in 2024 from the University of California, Davis, where as a NIH Fogarty / UC Global Health Institute GloCal Fellow her research addressed the associations between soil microbiota, human gut microbiota, and childhood diarrheal disease burden in rural households in western Kenya. Her interest in applied research in East Africa was sparked as a MSc student in International Agricultural Development, when she co-developed a protocol for participatory and community-based evaluation of horticulture irrigation systems alongside smallholder farmers in eastern Uganda.

In the Gilbert lab, Mariah is conducting research addressing how exposure to environmental microbiota, including those in soils, shapes human microbial communities and how this in turn affects health. Her publications are here.

Graduate Students

Marisol (Dottie) Dothard

PhD Student

Dottie Dothard (she/her) is a second-year PhD student in the Gilbert lab at the University of California, San Diego. Dottie completed degrees in Biology and Classical Voice from Bard College in 2017. She went on to complete a post-baccalaureate research program at the University of Pennsylvania, where she used a mix of bioinformatics and molecular biology approaches to hunt for novel viruses in the human lung. After finishing her post-baccalaureate studies in 2019, she earned a Master’s Degree in Molecular Biology, Cellular Biology, and Biochemistry from Boston University. Her thesis work focused on unique motility mechanisms of several marine microbe strains. During her Masters, Dottie was awarded the prestigious National Science Foundation Graduate Research Fellowship Program (NSF GRFP). Dottie is still fascinated by the sociological doings of microbes and aims to focus her PhD research at UCSD on increasing our understanding of the microbiomes of transgender individuals in order to better inform transgender healthcare. In her free time, Dottie is the editor of a small literary magazine through the Biomedical Sciences program at UCSD and enjoys freelance writing gigs, reading, and editing. Dottie is a passionate community advocate and is involved in several community service projects including volunteer programs oriented to increase book access for incarcerated individuals and paid community advocacy as Community Liaison for the Black Graduate Education Living and Learning Community at UCSD.


Neil Gottel

PhD Student

Neil (he/him) graduated from the University of Illinois at Urbana-Champaign with a B.S. in Integrative Biology, where he studied the nitrogen fixing microbes living within the potential biofuel crop Miscanthus giganteus. He then studied the microbiome of various poplar tree species at Oak Ridge National Laboratory, then attended graduate school at the University of Texas Austin. He returned to Chicago to work at Argonne National Laboratory, and joined the Gilbert lab as a technician. After surviving the Technician Battle Royale, he became the lab manager at its University of Chicago location. He is now at UCSD, in SIO’s marine biology graduate program. His publications can be found here.


Sho Kodera

PhD Student

Sho (he/him) graduated from UC San Diego with a B.S. in Ecology, Behavior, and Evolution. He then obtained his M.S. under Dr. Stuart Sandin at Scripps Institution of Oceanography, focusing on coral reef ecology and life history. He then worked as a staff research associate with the 100 Island Challenge project at Scripps, where he conducted extensive SCUBA field surveys in various tropical coral reef communities around the world. He now conducts research in microbial ecology; his research interests involve understanding broad-scale ecological concepts through the examination of microbial dynamics in rivers, marine mammals, humans, and coral reefs. He is interested in applying such knowledge towards developing actionable strategies that can push microbial communities toward healthier, more stable states. His publications can be found here.


Emily Kunselman

PhD Student

Emily (she/her) graduated from the University of California, San Diego with a B.S. in Marine Biology. As an undergraduate, she completed her honor’s thesis on the microbiome of the Olympia oyster in the Puget Sound. She continues to work on oysters during her PhD, studying how an oyster virus, OsHV-1, impacts the oyster microbiome and how temperature dictates viral proliferation. She has also expanded into a new mollusk, the endangered white abalone.  She studies how the microbiome of white abalone responds to a bacterial disease called Withering Syndrome. Emily is broadly interested in aquaculture, which has driven her to study the interactions between climate change, disease and the microbiome, all of which greatly impact shellfish and aquaculture operations.

Vanessa Minnis

PhD Student

Vanessa (she/her) graduated from UCSD with her B.S. in Environmental Systems/Environmental Chemistry in 2023. Vanessa is interested in ecotoxicology and the impacts on human health through the lens of microbial environments. She has conducted independent research, under the supervision of Dr. Megan Hill, on the microbiome of built environments, specifically focusing on antibiotic resistance from isolates collected on the International Space Station. Vanessa is pursuing her PhD in Marine Biology where she continues researching the impacts the environment has on human health and microbial communities.

Joshua Tran

PhD Student

Joshua (he/him) graduated from UC San Diego with a B.S. in Human Biology in 2023. As an undergraduate, Joshua’s research interest broadly involved studying the interactions between the gut microbiome and cancer development under Dr. Jack Gilbert (Scripps Institute of Oceanography/UCSD Department of Pediatrics) and Dr. Georgia Sadler (UCSD Moores Cancer Center). Now, as a PhD student in the Gilbert lab, Joshua is thrilled to learn more about the microbial interactions in and around the body and their role in health but specifically, cancer. His current research aims to understand how dietary interventions impact inflammation and microbiome structure post-colonoscopy for elevated colorectal cancer risk patients.

Kara Wiggin Photo

Kara Wiggin

PhD Student

Kara (she/her) graduated from Northeastern University in 2014 with a B.S. in Environmental Science. In 2019, she obtained her M.S. at Cal State Long Beach in Dr. Erika Holland’s Tox Lab, where she studied the detection and toxicity of microplastic pollution. She is now pursuing her PhD in Marine Biology at SIO. Kara is still pursuing questions related to microplastic pollution, but is now approaching her research from a microbiology perspective, studying the role of microplastics in pathogen transmission in the marine environment.

Ryan Chung

Masters Student

Ryan graduated from UCSD with his B.S. in Marine Biology and minor in Environmental Systems in 2023. He is currently pursuing a masters degree in Marine Biology at SIO. Ryan is broadly interested in the interplay between marine organisms and human health, with a recent focus on marine microbes and their pathogenicity in humans. As an undergraduate lab technician, he helped conduct experiments aimed at quantifying microplastic pollution and microplastics as pathogen vectors in oysters. Ryan hopes to continue in academia before transitioning to a teaching role, where he hopes to inspire students to pursue research opportunities as undergraduates.

Undergraduate Students

Davis Bone

Undergraduate Student

Davis (he/him) is a rising 3nd year undergraduate student studying Biology and Biomedical Engineering at Johnson & Wales University in Providence, RI. His broad interests in the gut microbiome and human health led him to start with the Gilbert Lab in the summer of 2022. He is currently visiting the lab for his third summer rotation, working in data analysis and assisting with experiments in the lab. After the summer, Davis will continue his undergraduate studies and hopes to be continue to be involved in microbiome and human health related research in the future.

Jacob Hizon

Undergraduate Student

Jacob (he/him) is a 1st year undergraduate student at UCSD studying microbiology. Volunteering as a lab aide at Sharp Chula Vista during his high school years exposed him to the ins and outs of a clinical laboratory setting and sparked a continuous interest in microbial studies. Jacob is particularly interested in investigating the complexities of the human gut microbiome and the microbial world around him. After graduation, Jacob intends to pursue a graduate degree in the biological sciences. He joins the team at Gilbert lab under the National Cancer Institute-funded Multidisciplinary Educational approach to Reducing Cancer Disparities Program.

Rebecca Mendoza

Undergraduate Student

Rebecca (she/her) is an undergraduate student at California State University San Marcos pursuing a B.S. in biology, with the intent to pursue a career in health care. She has been volunteering at Palomar Health for almost a year now. As a REM intern, she is researching microbial competition in the built environment in the Gilbert lab. She is a first-generation Mexican American and hopes to continue her path in STEM while proudly representing her community.

MariaJose Ruiz Gamboa

Undergraduate Student

MariaJose is a second year undergraduate student studying Biochemistry at Southwestern College. With a strong academic background and practical experience in various scientific laboratories, she has developed a passion for understanding the molecular mechanisms of life, particularly the intricate world of microbiomes. As the founder and president of the Ecoaction Club, MariaJose has developed leadership and teamwork skills, driving initiatives to promote environmental sustainability within her community. Her goal is to contribute to scientific advancements that can make a positive impact on the world, with a particular interest in the study of microbiomes and their potential to solve environmental and health-related challenges. This summer, MariaJose joins the lab through the JT-SURF program.

Audrey Schneider

Undergraduate Student

Audrey (she/her) is a second year undergraduate student at UC San Diego majoring in Marine Biology. Originally from Denver, Colorado, Audrey completed an International Baccalaureate high school diploma and then a Summer of Service doing environmental work with AmeriCorps before arriving in San Diego in 2022. In summer 2023, she served as an intern at the National Renewable Energy Laboratory in Boulder, CO, completing a literature review of sustainable wave energy technology and the potential impacts on the ocean environment. She is excited to be learning about lab work in her dream environment, Scripps Institution of Oceanography. She is interested in exploring the interconnectivity between conservation, ecology, and the microbiome. Outside of the lab, Audrey enjoys cooking, playing frisbee, scuba diving, and traveling. 

Johnny Tran

Undergraduate Student

Johnny (he/him) is a third-year student studying Environmental Systems in the Ecology, Behavior, and Evolution track with a minor in General Biology. He originally attended Orange Coast College where he received his A.S. in Natural Science and A.A. in Liberal Arts.  From here he was able to find his interest in marine sciences after researching bottlenose dolphins’ migration patterns. He has an interest in environmental toxicology and understanding how the environment interacts with the biosphere. When he’s not in the lab you can find him on the beach flying his kite!

Chris Zhang

Undergraduate Student

Chris is a 3rd year undergraduate Marine Biology major at UCSD. He enjoys studying anything and everything that relates to marine life and the oceans, and he is excited to research how microbiology relates to ocean life. Chris hopes to go to graduate school for an MS for Marine Biology. He joins the Gilbert lab as part of the National Cancer Institute-funded Creating Scientists to Address Cancer Disparities program. 



Mariana Salas Garcia

Lab Manager

Mariana is an experienced lab manager with a strong background in biochemistry, pre-medicine, and microbiology. With a B.A. in Biochemistry and Pre-Medicine from Judson University, her passion for understanding the microbial world and its impact on human health has driven her specialization in microbiome research. Mariana has a Master’s degree in project management, allowing her to effectively oversee and coordinate diverse, multidisciplinary projects within the laboratory. With her entrepreneurial mindset and problem-solving abilities, she excels in resource management, workflow optimization, and ensuring the successful execution of research initiatives. Mariana’s dedication and leadership skills foster an efficient and productive lab environment, promoting collaboration and innovation among the team members. Her publications can be found here.


Mary Buschmann

Grant Writer and Coordinator

Mary holds a BA in Biology from Concordia University, Ann Arbor, MI, and a PhD in Cell and Cancer Biology from the University of Cincinnati. She did her postdoctoral research at the University of Chicago as a Ruth L. Kirschstein National Research Service Award Fellow, studying gut epithelial barrier function. Prior to joining the Gilbert group, Mary spent almost 5 years overseeing the Chicago Pancreatic Cancer Initiative at the University of Chicago, which was a clinical research program studying ways to use patient genomic, clinical, and demographic data and personalized cell line models to improve understanding and treatment of the disease. Concurrent with this, she managed the University of Chicago’s Department of Surgery grant and clinical research portfolio. In the Gilbert lab, Mary utilizes these experiences to coordinate collaborative research programs, prepare funding applications and research articles, and manage human research regulatory affairs for the group.


Megan Cunningham


Megan (formerly Megan Preovolos) is a native San Diegan (born and raised!) and joined the Gilbert Lab January 2, 2019, before anyone else had actually arrived in San Diego.  She is a UCSD Alumni, graduating with her BS in Cognitive Science in 2007.  In the Gilbert Lab,  Megan provides administrative support in many aspects of the lab, trying to do everything she can to make the lab members’ lives just a little bit easier. Outside of work Megan loves to travel, scuba dive, and train and fundraise with Team Challenge in honor of the Crohn’s and Colitis Foundation.  

Previous Lab Members

  • Nicole Bardales (undergraduate research assistant and lab technician)
  • Rachel Diner (postdoc) – Assistant Professor of Biological Sciences, University of Memphis
  • Carolina Carpenter (graduate student) – Graduate Student, SIO (Andy Allen lab)
  • Zachary Daniel (undergraduate research assistant) – Graduate Student, SIO (Jensen lab)
  • Davis Bone (high school and undergraduate research assistant) – Undergraduate Student, Johnson & Wales University
  • Antoinette Jane (AJ) Dizon (undergraduate research assistant, REM program)- Undergraduate Student, California State University San Marcos
  • Daysi Manrique (undergraduate research assistant, SURF program)- Undergraduate Student, Pomona College
  • Nolan Sigmund (laboratory assistant)- Laboratory Technician, UCSD Psychology
  • Ella Rushton (visiting undergraduate researcher) – Undergraduate Student, University of the West of England, UK
  • Maria Gjerstad Maseng (visiting graduate student) – Graduate Student, University of Oslo and Bio-Me
  • Alexander Mahnert (visiting postdoc) – Postdoc, Medical University of Graz, Austria
  • Holly Lutz (postdoc and assistant project scientist) – Postdoctoral Affiliate, Andersen Lab, Scripps Research Institute
  • Lisa Marotz (postdoc) – Microbiome Scientist, Native Microbials, Inc
  • Farhana Ali, MD (clinical research fellow) – Pediatric Gastroenterologist, Intermountain Primary Children’s Hospital
  • Jessica Gallant-Swafford, MD (clinical research fellow) – National Jewish Health
  • Leslie Chiang, MD (clinical research fellow)
  • Kathryn Van Artsdalen (laboratory technician)
  • Natalie Grayson (graduate student) – PhD Student, Moore lab at SIO-UCSD
  • Promi Das (postdoc) – Project Manager, Center for Microbiome Innovation
  • Sophia Carryl (graduate student) – Postdoctoral Research, Harvard (Haber lab)
  • Anukriti Sharma (postdoc) – Research Scientist II, Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic
  • Ali Sjaarda – University of Chicago
  • Alyson Yee – MD Student, University of Chicago Medical School
  • Beatriz Pelnaver – Assistant Professor, University of Illinois Chicago
  • Ben Temperton – Senior Lecturer in Bioinformatics, University of Exeter, UK
  • Bonnie Laverock – Research Fellow at Auckland University of Technology
  • Cesar Cardona – Sr. Bioinformatics Cloud Engineer, Second Genome, CA
  • Chris Marshall – Assistant Professor of Applied and Environmental Microbiology, Marquette University, WI
  • Daniel Smith – Bioinformatics Programmer, Baylor College of Medicine
  • Elle Hill – Research Assistant/Technician, University of Chicago & Argonne National Library
  • Haitao Wang – Postdoctoral Research University of Greifswald, Germany
  • Iratxe Zarraonaindia –  Ikerbasque Research Associate, Department of Genetics, Physical Anthropology and Animal Physiology, Univ of the Basque Country UPV/EHU, Spain
  • Jarrad Marcell-Hampton – Postdoctoral Researcher (Bridge to Faculty Program), University of Illinois Chicago
  • Kassandra Brown – Princeton/Yale
  • Kim M. Handley – University of Aukland
  • Lauren Cralle – MD Student, University of Massachusetts Medical School
  • Leron Perez – Graduate Student, Stanford School of Medicine
  • Madeline Kim – Medical Student at the Icahn School of Medicine
  • Melissa Dsouza – Commense Health, Boston MA
  • Miles Richardson – PhD Student, Columbia University
  • Na Fei – Postdoctoral Research Chang Lab, University of Chicago
  • Naseer Sangwan – Director of Microbiome Core, Cleveland Clinic
  • Nicole Scott – Biota Inc
  • Pamela Weisenhorn – Argonne National Laboratory
  • Sean M. Gibbons – Assistant Professor, Institute for Systems Biology, University of Washington
  • Simon Lax – Postdoctoral Research Associate, MIT
  • Simon Thomas – Principle Researcher, Plymouth Marine Laboratory, UK
  • Tom Kuntz – Postdoctoral Research, Harvard (Huttenhower lab/Microbiome Analysis Core)
  • Victor S. Pylro – Argonne National Laboratory
  • Wyatt Arnold – PhD Student, Yale University