Locally adapted gut microbiomes mediate host stress tolerance.

Area of Science:

• Ecology
• Microbiology
• Evolutionary Biology

Background:

• Host microbiome influences stress tolerance.
• Local adaptation of microbiomes is less understood.
• Investigating host-microbiome interactions in Daphnia magna.

Purpose of the Study:

• Determine if locally adapted gut microbiomes improve host stress tolerance.
• Assess the impact of sympatric vs. allopatric microbiomes on Daphnia magna.
• Examine the role of cyanobacteria exposure in host-microbiome adaptation.

Main Methods:

• Reciprocal transplant experiment with germ-free Daphnia magna.
• Inoculation with sympatric and allopatric microbiomes from different ponds.
• Exposure to toxic cyanobacteria (Microcystis aeruginosa).
• Assessed host life history traits and gut microbiome composition.

Main Results:

• Daphnia magna performed better with sympatric microbiomes.
• Pre-exposure of donors to cyanobacteria amplified the benefit.
• Effects were dependent on pond origin and host genotype.
• Host fitness benefits linked to microbiome diversity.

Conclusions:

• Daphnia magna exhibit local adaptation in stress tolerance mediated by specific microbial strains.
• Symbiotic relationships between hosts and local microbiomes are crucial for environmental resilience.
• Microbiome composition and diversity play a key role in host adaptation to environmental stressors.