It depends on where in the world they live. Most defense in first world nations is simply prevention of confrontation before it can happen, through the use of security, police and military forces. In less civilized areas and nations, this is accomplished through safety in numbers and intimidation. When confrontation cannot be prevented, it is done either with force (such as using weapons or fighting), or by negating the force of the opposing faction, with the use of simple tactics such as using defensive fortifications (walls, fences, bunkers etc) or simply fleeing.
Porcupines defend themselves with their quills.
Male honey bees (drones) can't defend themselves as they are incapable of stinging.
Dogs use their teeth and strong jaws to defend themselves.
neddles retard
to defend themselves
They use their claws, paws, and teeth.
Porcupines defend themselves with their quills.
nuclear weapons
No, crayfish use claws and force to defend themselves
They defend themselves by releasing disgusting slime when attacked.
No, crayfish use claws and force to defend themselves
Primarily crickets jump or fly away from animals that endanger them. Crickets have been known to use their relatively strong jaws to defend themselves from time to time.