Chemical communication is all about taste and smell. Plants use scent and pheromones to attract pollinators. Animals use scents and tastes for a whole variety of reasons, including scents emitted by female moths to attract a mate, alarm signals given off by bees when their hive is under threat and the territorial markers in wolf urine. Some insects, such as ants, lay down pheromone trails for their nest-mates to follow to food sources. Many animals have special scent glands for leaving these chemical messages.

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