Environmental fluctuations reshape an unexpected diversity-disturbance relationship in a microbial community
- Boston University, United States
- Massachusetts Institute of Technology, United States
Abstract
Environmental disturbances have long been theorized to play a significant role in shaping the diversity and composition of ecosystems. However, an inability to specify the characteristics of a disturbance experimentally has produced an inconsistent picture of diversity-disturbance relationships (DDRs). Here, using a high-throughput programmable culture system, we subjected a soil-derived bacterial community to dilution disturbance profiles with different intensities (mean dilution rates), applied either constantly or with fluctuations of different frequencies. We observed an unexpected U-shaped relationship between community diversity and disturbance intensity in the absence of fluctuations. Adding fluctuations increased community diversity and erased the U-shape. All our results are well-captured by a Monod consumer resource model, which also explains how U-shaped DDRs emerge via a novel 'niche flip' mechanism. Broadly, our combined experimental and modeling framework demonstrates how distinct features of an environmental disturbance can interact in complex ways to govern ecosystem assembly and offers strategies for reshaping the composition of microbiomes.
Data availability
All sequencing data is deposited in the Sequence Read Archive (SRA) accessible with a BioProject accession code PRJNA719465. Agar plate images are deposited on Figshare accessible at doi.org/10.6084/m9.figshare.15117558. Computer code used to run eVOLVER experiments and for theoretical modeling is available at github.com/khalillab. All other datasets required to produce the results in the current study are included as supplemental data. Source data files have been provided.
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DDR64 Petri Dish Photosfigshare, https://doi.org/10.6084/m9.figshare.15117558.v1.
Article and author information
Author details
Funding
Defense Advanced Research Projects Agency (HR001115C0091)
- Ahmad S Khalil
Defense Advanced Research Projects Agency (HR001117S0029)
- Ahmad S Khalil
Simons Foundation (542385)
- Jeff Gore
National Institute of General Medical Sciences (R01GM102311)
- Jeff Gore
National Institute of Biomedical Imaging and Bioengineering (R01EB027793)
- Ahmad S Khalil
National Institutes of Health (DP2AI131083)
- Ahmad S Khalil
National Science Foundation (MCB-1350949)
- Ahmad S Khalil
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Mancuso et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Environmental fluctuations reshape an unexpected diversity-disturbance relationship in a microbial community
eLife 10:e67175.
https://doi.org/10.7554/eLife.67175
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