Scarifying involves scratching, etching, burning / branding, or superficially cutting designs, pictures, or words into the skin as a permanent body modification. In the process of body scarification, scars are formed by cutting or branding the skin. There are currently 4 competing hypotheses behind the behavior ecology of scarification:

- a rite of passage,
- a hardening/trauma procedure, 
- a nonadaptive sexually selected character, or 
- an adaptive pathogen-driven sexually selected character.
There are also aesthetic, religious, and social reasons for scarification.