Most Aggressive Animals

Aggression scores are built from field encounter data, documented attack records, and species ethology. Each animal is rated 1 to 10 on baseline territorial and defensive behaviour, and not maximum aggression under provocation, which most species can exceed under extreme pressure.

A 9 or 10 means confirmed unprovoked attacks on humans under typical encounter conditions. Scores below 5 indicate species that strike only when cornered, injured, or defending young. All 48 species are scored.