Chemical defense refers to the use of chemical substances by organisms to protect themselves from predators or harmful pathogens. Many plants and animals produce toxins or deterrent chemicals that can cause discomfort, illness, or even death to potential threats. For example, some species of frogs secrete toxic compounds through their skin, while certain plants release bitter-tasting chemicals to deter herbivores. In addition to natural toxins, some organisms can also employ chemical signals to warn others of danger. For instance, when bees are threatened, they release pheromones that alert nearby hive members to prepare for defense. This form of communication enhances the survival of the group by coordinating a collective response to threats.