Metabarcoding vs Microhistology

Metabarcoding vs Microhistology: Comparing Dietary Analysis Methods

Tyler Kartzinel

Originally posted 1/6/2026.

At First Bite: Why Do Animal Diets Matter?

Understanding what animals eat is central to ecology, evolution, and conservation. Diets shape species interaction networks, how energy flows through food webs, and what animals can do when environments change. For decades, ecologists have inspected animal scats using microscopes to identify what they have been eating. Today, DNA-based approaches offer a powerful alternative.

So how do these two methods stack up—and when should you use each?

Savanna elephant eating from the understory at Mpala Research Centre in Kenya. Photo credit: Tyler Kartzinel

Metabarcoding vs Microhistology: Two Ways to Identify an Animal’s Food

​Metabarcoding vs. microhistology—how do these two diet analysis methods compare, and what do their differences mean for ecology and conservation?

Metabarcoding

• Data type: DNA fragments in feces or gut contents
• Resolution: Often species-level, though it can depend on local biodiversity
• Strengths: High taxonomic breadth, detects rare items
• Limitations: Laboratory biases, gaps in available reference data

Microhistology

• Data type: Plant or prey fragments viewed under a microscope
• Resolution: Often genus-level or broader functional group
• Strengths: Direct observation, low lab infrastructure
• Limitations: Time-intensive, biased toward hard-to-digest tissues

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Microhistology

Microhistology is the traditional workhorse of quantitative diet analysis in ecology. Researchers examine plant fragments, hair and bone, or other indigestible remains under a microscope and identify them by comparison to reference collections.

Why it’s still used

• Requires relatively simple lab equipment
• Long history of standardized protocols
• Provides visual confirmation of consumed material

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A key limitation is that soft, highly digestible foods often disappear during digestion, meaning some diet items may be underrepresented or omitted entirely.

🔗 Botanical composition of range herbivore diets: a review

Microhistology to reconstruct herbivore diets as imagined by ChatGPT. Researchers visually identify plant fragments under a microscope.

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Metabarcoding

Dietary DNA metabarcoding uses high-throughput DNA sequencing to identify what species are present in a sample based on short genetic markers called "barcodes." Instead of visually identifying fragments, researchers match sequences to reference databases.

Why it’s transformative

• Detects a broad range of taxa simultaneously
• Captures rare or highly digested food items
• Scales efficiently to large sample sizes

A key caveat is that results can depend heavily on which genetic marker is used and the completeness of reference libraries—the absence of evidence is not evidence of absence.

🔗Who is eating what: diet assessment using next generation sequencing​

Dietary DNA metabarcoding involves collecting samples, sequencing remnant food DNA fragments, and matching data to a reference library of species.

• ​You can use our free laboratory protocols
• Feel free to download our code to help analyze results
• We contract with academic and conservation organizations to sequence dietary DNA

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Metabarcoding vs. Microhistology: What’s Really so Different?

Researchers use both methods to answer the same question--what do animals eat?—but from different angles.

• Microhistology reflects what survives digestion and can be recognized visually
• Metabarcoding reflects what left detectable traces of DNA

Microhistology often emphasizes diet structure, meaning the proportional breakdown in how much an animal eats one broad kind of food compared to another. How much grass versus browse an herbivore eats is a common application in wildlife management, for example. By contrast, metabarcoding excels at revealing fine-grained differences in diet diversity and composition. Importantly, neither method provides a perfect measure of quantity: counts of fragments and sequence reads are both useful—albeit imperfect—proxies for the amount of food an animal has consumed.

The contrast is less about old technology versus new—and more about complementary lenses on the same ecological process.

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Why This Comparison Matters

Understanding reports based on metabarcoding vs. microhistology—and choosing which method to use in a study you might be planning—can influence:

• Estimates of dietary niche breadth
• Inferences about competition and resource partitioning
• Conservation decisions for threatened species

Methodological choices can shape ecological conclusions, so understanding their strengths and weaknesses constraints is important when evaluating data.

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What You Can Do

• If you’re a researcher: Match your method to your question and budget—not the trend in technology.
• If you’re a student: Learn both approaches to understand their strengths and weaknesses.
• If you’re a conservation practitioner: Ask how diet data were generated before acting on them.

🔗 Related post: Apportionment of dietary diversity in wildlife
🔗 Related post:  Avoid this one common pitfall in analyses of dietary DNA data

Explore More Upcoming Posts In This Series

• Metabarcoding vs Stable Isotopes *Coming soon*
• Metabarcoding vs Direct Observation *Coming soon*
• Metabarcoding vs Metagenomics *Coming soon*