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Updated: Apr 24, 2026
22:38
Chemotactic Response of Marine Micro-Organisms to Micro-Scale Nutrient Layers
Published on: May 28, 2007
12.9K
Biogeographic patterns in ocean microbes emerge in a neutral agent-based model.
Ferdi L Hellweger1, Erik van Sebille2, Neil D Fredrick3
1Department of Civil and Environmental Engineering, Northeastern University, Boston, MA 02115, USA. ferdi@coe.neu.edu.
Science (New York, N.Y.)
|September 13, 2014
Summary
Neutral evolution significantly shapes marine microbial biogeography, creating distinct ocean provinces. Microbes evolve faster than ocean currents, leading to substantial genetic divergence and emergent spatial patterns.
Area of Science:
- Ecology
- Evolutionary Biology
- Marine Microbiology
- Computational Biology
Background:
- Understanding the drivers of biogeographic patterns is crucial in ecology and evolution.
- Distinguishing between neutral processes and natural selection in shaping biodiversity is a key challenge.
Purpose of the Study:
- To quantify the role of neutral evolutionary processes in generating marine microbial biogeographic patterns.
- To investigate the interplay between microbial evolution, cell division, mutation, death, and ocean circulation.
Main Methods:
- Simulated 100,000 individual marine bacteria with 1 million-base-pair genomes in a global ocean circulation model.
- Ran simulations for up to 100,000 years.
- Analyzed simulation output using Basic Local Alignment Search Tool (BLAST) alignment and metagenomics fragment recruitment.
Main Results:
- Simulations successfully produced and maintained substantial biogeographic patterns, including distinct microbial provinces.
- Observed patterns characterized by provincial mixing, neighbor takeovers (coalescence), and subsequent reestablishment of patterns by neutral evolution.
- Demonstrated significant DNA identity differences (down to 99.5%) between provinces, suggesting rapid microbial evolution relative to dispersal.
Conclusions:
- Neutral evolutionary processes play a substantial role in establishing and maintaining marine microbial biogeographic patterns.
- Microbial evolution rates appear to exceed ocean current dispersal rates, leading to genetic divergence.
- The simulation approach provides a framework for exploring environmental selection in microbial populations.
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