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Using Ponds and Aquatic Organisms to Understand Host-Microbe-Environment Interactions Across Geographic and Temporal
Kevin D Kohl1, Allison Suddaby1, Jose Goyco-Blas1
1Department of Biological Sciences, University of Pittsburgh, PA 15260, USA.
Integrative and Comparative Biology
|May 27, 2026
Summary
Freshwater ponds and tadpoles reveal how local environments shape gut microbes. Environmental factors and geography influence microbial communities in tadpole guts, impacting host health.
Area of Science:
- Ecology
- Microbiology
- Environmental Science
Background:
- Freshwater ecosystems are key for studying biological organization.
- Host-microbe interactions are increasingly understood, offering insights into how environment shapes local microbial communities and host fitness.
- Temperate freshwater ponds and larval amphibians (tadpoles) serve as effective models for these interactions.
Purpose of the Study:
- To investigate the influence of landscape and regional factors on local microbial communities and host-associated microbes.
- To examine how these interactions affect holobiont performance and fitness in tadpoles.
- To analyze the gut microbiomes of wood frog tadpoles (Lithobates sylvaticus) in relation to their aquatic environment.
Main Methods:
- Empirical data collection from wood frog tadpoles and their surrounding aquatic environments across multiple sites in Western Pennsylvania.
- Analysis of aquatic microbial communities and tadpole gut microbiomes.
- Statistical analysis to determine the contribution of local environmental conditions, geographic distance, and time to community composition.
Main Results:
- Aquatic microbial communities exhibited higher diversity than amphibian-associated communities.
- Local environmental conditions significantly influenced tadpole gut microbial community membership.
- Community composition varied significantly across ponds and months, with geographic distance and environmental variables (dissolved oxygen, pH) driving turnover.
- Specific microbial taxa were found to be enriched in tadpole guts beyond neutral expectations, indicating deterministic selection processes.
Conclusions:
- Local environmental conditions and geographic factors play a significant role in shaping tadpole gut microbiomes.
- Deterministic processes likely contribute to the selection and retention of specific microbes within the tadpole gut.
- Further research with expanded geographic and temporal sampling, along with controlled experiments, is needed to fully understand the mechanisms and directionality of host-microbe-environment interactions.
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