Why do some animals have venomous stingers?

Venomous stingers are used by animals as a defense mechanism or to subdue prey. Many species of bees, wasps, and scorpions possess stingers that inject venom when threatened. The venom causes pain, paralysis, or even death in their prey, allowing the animal to catch or defend itself. In some cases, such as in the case of certain species of frogs and fish, venomous spines are used as protection against predators. The venom also acts as a deterrent, making the stinger-bearing animal dangerous or unpalatable to potential threats.