Armour (zoology)

Armor or armour in animals is a rigid cuticle or exoskeleton that provides exterior protection against attack by predators,[1] formed as part of the body (rather than the behavioural utilization of external objects for protection) usually through the thickening and hardening of superficial tissues, outgrowths or skin secretions.

It is often found in prey species that are too slow or clumsy to outrun predators,[2] or those that would stand their ground and fight, thus needing to shield vital organs against claw, talon or bite injuries.

Armoured structures are usually composed of hardened mineral deposits, chitin, bone, or keratin.

Most reptiles have scaly skin which protects them from predators in addition to water retention; the crocodile's scutes and the shells of the Chelonia: tortoises, turtles and terrapins.

Similarly, the hairy plate-like scales of the pangolin are employed in the same way and are constructed of the same material used in the offensive armour, the horn, of the rhinoceros.