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Title: Seasonal environmental variability drives microdiversity within a coastal Synechococcus population
Summary

Marine microbes often show a high degree of physiological or ecological diversity below the species level. This microdiversity raises questions about the processes that drive diversification and permit coexistence of diverse yet closely related marine microbes, especially given the theoretical efficiency of competitive exclusion. Here, we provide insight with an 8‐year time series of diversity withinSynechococcus, a widespread and important marine picophytoplankter. The population ofSynechococcuson the Northeast U.S. Shelf is comprised of six main types, each of which displays a distinct and consistent seasonal pattern. With compositional data analysis, we show that these patterns can be reproduced with a simple model that couples differential responses to temperature and light with the seasonal cycle of the physical environment. These observations support the hypothesis that temporal variability in environmental factors can maintain microdiversity in marine microbial populations. We also identify how seasonal diversity patterns directly determine overarchingSynechococcuspopulation abundance features.

 
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Award ID(s):
1655686
NSF-PAR ID:
10370491
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Environmental Microbiology
Volume:
23
Issue:
8
ISSN:
1462-2912
Page Range / eLocation ID:
p. 4689-4705
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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