Microbial Diversity Metric
What is Microbial Diversity?
Microbial Diversity measures the variety of microorganisms present in a sample and how evenly they are distributed. Higher diversity often indicates a healthier, more resilient microbial ecosystem.
Types of Diversity
Alpha Diversity (Within-Sample)
Measures diversity within a single sample:
- Richness: Number of different species
- Evenness: How equally abundant species are
- Common Metrics: Shannon Index, Simpson Index, Chao1
Beta Diversity (Between-Samples)
Measures differences between samples:
- How similar/different are two microbiome samples?
- Common Metrics: Bray-Curtis, UniFrac, Jaccard
Interpreting Diversity
| Diversity Level | Interpretation |
|---|---|
| High | Many species, evenly distributed; typically healthy |
| Low | Few species or one dominant; may indicate dysbiosis |
| Variable | Changes over time may indicate instability |
Clinical Significance
Low microbial diversity is associated with:
- Inflammatory bowel disease (IBD)
- Obesity and metabolic syndrome
- Antibiotic use
- Aging
- Recurrent infections
Related Terms
- Alpha Diversity: Within-sample diversity
- Microbiome: The microbial community
- Metagenomics: Method to measure diversity