The MuLTEE has been running since 2018, with daily transfers. The experiment is maintained by a small permanent core, a rotating group of graduate and undergraduate researchers, and collaborators on three continents.
Leads and contacts
Professor, School of Biological Sciences, Georgia Tech
Co-founder of the MuLTEE. He developed the snowflake yeast system from around 2010 as a postdoc in Michael Travisano's lab at the University of Minnesota, where daily settling selection was first used to evolve multicellularity de novo, and moved to Georgia Tech in 2014. Senior author of the 2023 Nature macroscopic-size paper and co-PI on the NSF LTREB award that funds the experiment.
Senior Research Scientist, Georgia Tech
Co-founder of the MuLTEE, and the person who runs it day to day. He proposed and designed the metabolic treatment scheme that removed the oxygen limit on cluster size, founded the original twenty populations in 2018, and kept fifteen of them going after that study ended, which is what made the MuLTEE long-term. First author of both the 2021 oxygen paper and the 2023 Nature macroscopic-size paper, and PI on NSF award 2452109, the LTREB grant behind the 2025–2035 decadal plan.
Strain requests · scientific scoping
Research Scientist, Georgia Tech
Joined the lab in 2021. She manages strain distribution and leads omics data collection, and is studying the role of Hsp90 in macroscopic adaptation through a replay evolution experiment. Co-author on the 2023 macroscopic-size, 2024 coexistence, 2024 Hsp90 and 2025 genome-duplication papers.
Strain requests · logistics and shipping
Current contributors
Research Scientist, Georgia Tech
Studies how life gets around the limit that oxygen places on multicellular size, including phototrophy and oxygen-binding globins. Senior author of the 2025 PLOS Biology paper on oxygen-binding proteins. Co-author on the 2023 macroscopic-size, 2024 Hsp90 and 2024 entanglement papers. PhD from Duke on the yeast metabolic and cell division cycles.
PhD student, QBioS
Works on the life history of nascent multicellular yeast and the evolution of cell differentiation. Co-author on the 2025 genome-duplication paper and the 2025 super-resolution imaging paper. BS-MS from IISER Pune.
PhD student, QBioS
First author of the 2025 paper on coordinated cell division, which showed that the anaerobic lines lost the ancestral first-division delay by day 200 and stayed synchronous through day 1,000. He began on evolved trade-offs in snowflake yeast during a year-long internship before the PhD. Genomic Sciences, UNAM.
PhD student, Biology, Georgia Tech
Working with Dung Lac and Ozan Bozdag on emergent gene expression patterns in S. cerevisiae under anaerobic, mixotrophic and aerobic regimes.
Lab technician, Georgia Tech
Completed his Master's in the lab and now works there as a lab technician. Tests whether evolved MuLTEE strains can revert to unicellularity by engineering a functional ACE2 allele back into them.
PhD student, Biology, Georgia Tech
Studies the entrenchment of multicellularity in the MuLTEE lines through genetic engineering and experimental evolution. BSc in Computational Biology, University College London.
PhD student, QBioS
Works on the evolution of metabolically driven flows in the anaerobic (PA) populations. BEng, Waseda University, 2026.
Visiting undergraduate, Imperial College London
Examines how population size and cluster size differ between microscopic and macroscopic populations, and what those differences mean for population genomics.
The lab is larger than this list. Named here are the members currently working on MuLTEE populations; the full roster is on the Ratcliff Lab people page.
Alumni credits
Much of the work described on this site was done by researchers who have since moved on.
Many more people worked on the lab's earlier snowflake yeast research; those papers are on the Publications page.
Collaborators
Any population from any archived timepoint can be requested, and sharing the archive is a central aim of the project. Requests go through the strain request page. For anything else, write to Ratcliff or Bozdag at the addresses above.