Acquired Characteristics
Definition
Individual characteristics that develop after manufacture through use, wear, damage, or corrosion. A new shoe has only class characteristics; a worn shoe accumulates acquired marks that may make it unique.
- Origin
- Develop after manufacture
- Causes
- Use, wear, damage, corrosion
- Contrast
- Class characteristics, present from manufacture
- Example
- Wear marks on a shoe outsole
- Evidentiary value
- Can support individualisation
Common questions
Why can a worn shoe be individualised while a brand-new shoe cannot?+
A new shoe carries only the class characteristics shared by every pair made from the same mould, but wear, damage, and embedded debris accumulate randomly during use, producing a pattern of marks unlikely to be duplicated on any other shoe.
Do acquired characteristics change over time, and does that affect comparisons?+
Yes, ongoing wear continues to alter them, so an examiner must consider how much time separates the questioned impression and the exemplar and account for characteristics that may have appeared, changed, or disappeared in between.
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