Venom dripping out of a prairie rattlesnake


Venomous organisms inflict poisonous wounds by actively biting, stinging or scratching their victims and injecting toxins into them. This distinguishes them from poisonous species which usually contain or secrete toxins and need to touched or eaten to contaminate their victims. Envenomation can be a predatory tactic or a defence mechanism. It can be costly to produce and to inject toxins, so often organisms will use as little venom as possible in an attack.

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