Testa Fragment
Definition
A portion of the seed coat. Testa fragments from food seeds (sesame, tomato, raspberry, fig, and so on) retain species-diagnostic surface sculptures and are identifiable in gastric and intestinal contents.
- Origin
- Seed coat of a food plant
- Example sources
- Sesame, tomato, raspberry, fig
- Identification method
- Surface sculpture examined microscopically
- Context found
- Gastric and intestinal contents
Common questions
What can testa fragments tell an investigator?+
Because seed coats survive digestion far longer than soft food tissue, identifying which plant species are present helps corroborate or challenge an account of what and when a person last ate before death.
How reliable is species identification from a fragment?+
Species-diagnostic surface sculpture is often preserved even in a partial fragment, but identification depends on the examiner's reference collection and expertise, and a badly degraded fragment may only be identifiable to a plant family rather than a species.
Related terms
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