Pangolins can roll up almost instantaneously when threatened. Reflex is triggered by sight, smell, or touch. The overlapping scales interlock to form an impenetrable ball. This behavior deters most predators. Young pangolins learn curling early. Speed of curling is critical in survival.
It shows a combination of instinct, behavior, and anatomy for protection.
Evolution favors rapid reflexes in high-risk prey species.
A curled pangolin can withstand dog bites and lion attacks without injury.
Smithsonian National Zoo (si.edu)