Comparative study of gut microbiota diversity and its correlation with insect host diet and mobility in migratory Lepidoptera species.

Project Abstract

This study investigates the diversity and functional potential of gut microbiota in migratory Lepidoptera and examines how microbial communities correlate with host diet and mobility across seasonal migrations. We sampled adult and larval stages of multiple migratory Lepidoptera species from three geographically distinct flyways, employing high-throughput 16S rRNA gene sequencing to profile bacterial communities and shotgun metagenomics to infer microbial functional capacity. In parallel, detailed dietary assessments were conducted through direct observation, larval host-plant identification, and gut metabolite analysis to quantify plant-derived substrates and secondary metabolites encountered during migration. Mobility metrics were derived from mark-recapture data, flight mill experiments, and wing morphometrics to quantify flight capability, endurance, and energy expenditure. Bioinformatic pipelines were used to assess alpha and beta diversity, core microbiota, and differential abundance of taxa in relation to host diet categories (polyphagous vs. oligophagous), developmental stage, and migration phase (breeding, staging, and overwintering). Functional profiling focused on pathways related to digestion (cellulolytic and plant polysaccharide-degrading enzymes), detoxification (xenobiotic metabolism and plant secondary metabolite processing), and energy harvest (short-chain fatty acid production, glycolysis, and fatty acid ?-oxidation). We tested hypotheses that (i) gut microbial diversity increases with broader host-plant diet breadth and correlates with enhanced digestive enzyme repertoires, (ii) specific microbial taxa are associated with migration-relevant traits such as improved lipid utilization and reduced oxidative stress under energy-limited conditions, and (iii) seasonal shifts in microbiota composition align with changes in diet, gut physiology, and migratory stage. Multivariate analyses, including PERMANOVA and redundancy analysis, revealed significant differences in microbiota structure among species, developmental stages, and dietary guilds, with consistent core taxa across migratory populations that likely contribute to polysaccharide degradation and detoxification. Network analysis indicated cooperative interactions between gut bacteria and host metabolic genes, suggesting a symbiotic framework that supports rapid energy mobilization and resilience to dietary toxins encountered during long-distance movements. Correlation analyses demonstrated strong associations between specific microbial clades (e.g., Firmicutes and Proteobacteria) and host lipid metabolism markers, as well as indirect links to flight performance indicators such as wing loading and metabolic rate. This work identifies key microbial signatures linked to diet breadth and migratory physiology, providing insights into how gut microbiota modulate nutritional strategy and energy efficiency in migratory Lepidoptera. The findings have implications for understanding insect adaptation to diverse plant communities and changing migratory routes in the context of environmental perturbations, with potential applications in pest management and conservation biology where microbiome manipulation could influence host fitness along migratory corridors.

Project Overview

What This Project Is About

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A plain-language overview of the topic and what the project investigates.

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The Problem It Addresses

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What problem or gap this project tackles and why it matters to the field or society.

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Objectives of the Project

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1. Identify the gut microbiota present in selected migratory Lepidoptera species.
2. Explore how diet changes relate to shifts in gut microbial communities.
3. Examine how gut microbiota diversity may relate to butterfly and moth mobility patterns.
4. Compare microbiota between species with different migratory behaviors.
5. Discuss potential implications for insect health and host ecology.

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What You Will Do Step by Step

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1. Review available literature on gut microbes in Lepidoptera and related insects.
2. Collect insect samples from field sites representing different diets and migration statuses.
3. Extract DNA from gut samples and sequence microbial DNA (basic 16S rRNA profiling).
4. Analyze data to identify microbial communities and diversity metrics.
5. Correlate microbiota data with diet information and movement observations.
6. Summarize findings and discuss ecological implications.

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Expected Outcome

Clear understanding of how diet and movement relate to gut microbiota in migratory Lepidoptera, with practical insights for conservation and pest management.