Microbial evolutionary strategies in a dynamic ocean

Details

• Journal Title:
  Proceedings of the National Academy of Sciences of the United States of America
• Personal Author:
  Walworth, Nathan G. ; Zakem, Emily J. ; Dunne, John P. ; Collins, Sinéad ; Levine, Naomi M.
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; GFDL (Geophysical Fluid Dynamics Laboratory)
• Description:
  Marine microbes form the base of ocean food webs and drive ocean biogeochemical cycling. Yet little is known about the ability of microbial populations to adapt as they are advected through changing conditions. Here, we investigated the interplay between physical and biological timescales using a model of adaptation and an eddy-resolving ocean circulation climate model. Two criteria were identified that relate the timing and nature of adaptation to the ratio of physical to biological timescales. Genetic adaptation was impeded in highly variable regimes by nongenetic modifications but was promoted in more stable environments. An evolutionary trade-off emerged where greater short-term nongenetic transgenerational effects (low-gamma strategy) enabled rapid responses to environmental fluctuations but delayed genetic adaptation, while fewer short-term transgenerational effects (high-gamma strategy) allowed faster genetic adaptation but inhibited short-term responses. Our results demonstrate that the selective pressures for organisms within a single water mass vary based on differences in generation timescales resulting in different evolutionary strategies being favored. Organisms that experience more variable environments should favor a low-gamma strategy. Furthermore, faster cell division rates should be a key factor in genetic adaptation in a changing ocean. Understanding and quantifying the relationship between evolutionary and physical timescales is critical for robust predictions of future microbial dynamics.
• Keywords:
  Adaptation Advection Environment Epigenetic Mutations Evolution Fluctuating Marine Microbes Science Technology Timescales Epigenetic Mutations Marine Microbes

  More +
• Source:
  PNAS 117 (11) 5943-5948 https://doi.org/10.1073/pnas.1919332117
• DOI:
  https://doi.org/10.1073/pnas.1919332117
• Pubmed ID:
  32123112
• Document Type:
  Journal Article
• Rights Information:
  Other
• Compliance:
  PMC
• Main Document Checksum:
  urn:sha256:ee451b4827044f0f542dad109d714ca8dc9f35b5f1d57f82fc7b7d76c93da094
• Download URL:
  https://repository.library.noaa.gov/view/noaa/29084/noaa_29084_DS1.pdf
• File Type:
  [PDF - 965.73 KB ]